Merge branch 'master' into mkdir_with_intermediates

299 files changed, 7296 insertions, 8342 deletions

diff --git a/.github/PULL_REQUEST_TEMPLATE.md b/.github/PULL_REQUEST_TEMPLATE.md
index 70cc4bb85..3061f42b6 100644
--- a/.github/PULL_REQUEST_TEMPLATE.md
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@@ -1,4 +1,4 @@
-- [ ] Have you followed the guidelines in our [Contributing](https://github.com/Homebrew/brew/blob/master/.github/CONTRIBUTING.md) document?
+- [ ] Have you followed the guidelines in our [Contributing](https://github.com/Homebrew/brew/blob/master/CONTRIBUTING.md) document?
 - [ ] Have you checked to ensure there aren't other open [Pull Requests](https://github.com/Homebrew/brew/pulls) for the same change?
 - [ ] Have you added an explanation of what your changes do and why you'd like us to include them?
 - [ ] Have you written new tests for your changes? [Here's an example](https://github.com/Homebrew/homebrew/pull/49031).
diff --git a/.gitignore b/.gitignore
index 20b1a2dfd..118a02ff8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,11 +13,13 @@
 /Library/Homebrew/cask/bin
 /Library/Homebrew/cask/vendor
 /Library/Homebrew/cask/coverage
+/Library/Homebrew/cask/tmp
 /Library/Homebrew/test/.bundle
 /Library/Homebrew/test/bin
 /Library/Homebrew/test/vendor
 /Library/Homebrew/test/coverage
 /Library/Homebrew/test/fs_leak_log
+/Library/Homebrew/tmp
 /Library/LinkedKegs
 /Library/Locks
 /Library/PinnedKegs
diff --git a/Library/.rubocop.yml b/Library/.rubocop.yml
index d6dc0c429..99de0d8a2 100644
--- a/Library/.rubocop.yml
+++ b/Library/.rubocop.yml
@@ -4,6 +4,8 @@ inherit_from:
 
 AllCops:
   TargetRubyVersion: 2.0
+  Include:
+    - '**/.simplecov'
   Exclude:
     - 'Homebrew/cask/**/*'
     - 'Homebrew/vendor/**/*'
diff --git a/Library/.rubocop_rules.yml b/Library/.rubocop_rules.yml
index cde310930..543dc4018 100644
--- a/Library/.rubocop_rules.yml
+++ b/Library/.rubocop_rules.yml
@@ -1,4 +1,3 @@
-
 # ruby style guide favorite
 Style/StringLiterals:
   EnforcedStyle: double_quotes
@@ -7,17 +6,30 @@ Style/StringLiterals:
 Style/StringLiteralsInInterpolation:
   EnforcedStyle: double_quotes
 
+# only for numbers >= 1_000_000
+Style/NumericLiterals:
+  MinDigits: 7
+
+# zero-prefixed octal literals are just too widely used (and mostly understood)
+Style/NumericLiteralPrefix:
+  EnforcedOctalStyle: zero_only
+
 # percent-x is allowed for multiline
 Style/CommandLiteral:
   EnforcedStyle: mixed
 
+# depends_on foo: :bar looks rubbish
+Style/HashSyntax:
+  EnforcedStyle: ruby19
+  Exclude:
+    - 'Taps/**/*'
+
 # paths abound, easy escape
 Style/RegexpLiteral:
   EnforcedStyle: slashes
 
-# too prevalent to change this now, but might be discussed/changed later
 Style/Alias:
-  EnforcedStyle: prefer_alias_method
+  EnforcedStyle: prefer_alias
 
 # our current conditional style is established, clear and
 # requiring users to change that now would be confusing.
@@ -58,14 +70,6 @@ Lint/ParenthesesAsGroupedExpression:
 Style/EmptyLineBetweenDefs:
   AllowAdjacentOneLineDefs: true
 
-# port numbers and such tech stuff
-Style/NumericLiterals:
-  Enabled: false
-
-# zero-prefixed octal literals are just too widely used (and mostly understood)
-Style/NumericLiteralPrefix:
-  EnforcedOctalStyle: zero_only
-
 # consistency and readability when faced with string interpolation
 Style/PercentLiteralDelimiters:
   PreferredDelimiters:
@@ -93,15 +97,25 @@ Style/AlignParameters:
 
 # counterproductive in formulas, notably within the install method
 Style/GuardClause:
-  Enabled: false
+  Exclude:
+    - 'Taps/**/*'
 Style/IfUnlessModifier:
+  Exclude:
+    - 'Taps/**/*'
+
+# TODO: enforce when rubocop has fixed this
+# https://github.com/bbatsov/rubocop/issues/3516
+Style/VariableNumber:
+  Enabled: false
+
+# TODO: enforce when rubocop has shipped this
+# https://github.com/bbatsov/rubocop/pull/3513
+Style/TernaryParentheses:
   Enabled: false
 
 # dashes in filenames are typical
-# TODO: enforce when rubocop has fixed this
-# https://github.com/bbatsov/rubocop/issues/1545
 Style/FileName:
-  Enabled: false
+  Regex: !ruby/regexp /^[\w\@\-\+\.]+(\.rb)?$/
 
 # no percent word array, being friendly to non-ruby users
 # TODO: enforce when rubocop has fixed this
@@ -134,6 +148,7 @@ Style/MethodName:
 Style/PredicateName:
   Exclude:
     - 'Homebrew/compat/**/*'
+  NameWhitelist: is_32_bit?, is_64_bit?
 
 # `formula do` uses nested method definitions
 Lint/NestedMethodDefinition:
diff --git a/Library/.rubocop_todo.yml b/Library/.rubocop_todo.yml
index a898d2f79..6a38e100f 100644
--- a/Library/.rubocop_todo.yml
+++ b/Library/.rubocop_todo.yml
@@ -1,21 +1,11 @@
 # This configuration was generated by
-# `rubocop --auto-gen-config --exclude-limit 30`
-# on 2016-09-18 15:15:22 +0100 using RuboCop version 0.41.2.
+# `rubocop --auto-gen-config --exclude-limit 100`
+# on 2016-09-22 20:07:41 +0200 using RuboCop version 0.43.0.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
 # versions of RuboCop, may require this file to be generated again.
 
-# Offense count: 4
-# Cop supports --auto-correct.
-# Configuration parameters: AlignWith, SupportedStyles, AutoCorrect.
-# SupportedStyles: keyword, variable, start_of_line
-Lint/EndAlignment:
-  Exclude:
-    - 'Homebrew/download_strategy.rb'
-    - 'Homebrew/keg.rb'
-    - 'Homebrew/os/mac/cctools_mach.rb'
-
 # Offense count: 18
 Lint/HandleExceptions:
   Exclude:
@@ -52,11 +42,6 @@ Lint/NestedMethodDefinition:
     - 'Homebrew/dev-cmd/bottle.rb'
     - 'Homebrew/dev-cmd/test-bot.rb'
 
-# Offense count: 2
-Lint/NonLocalExitFromIterator:
-  Exclude:
-    - 'Homebrew/extend/pathname.rb'
-
 # Offense count: 28
 Lint/RescueException:
   Exclude:
@@ -80,12 +65,7 @@ Lint/RescueException:
 # Offense count: 1
 Lint/ShadowedException:
   Exclude:
-    - 'Homebrew/brew.rb'
-
-# Offense count: 2
-Lint/UselessAssignment:
-  Exclude:
-    - 'Homebrew/requirements.rb'
+    - 'Homebrew/utils/fork.rb'
 
 # Offense count: 18
 Metrics/BlockNesting:
@@ -94,64 +74,17 @@ Metrics/BlockNesting:
 # Offense count: 20
 # Configuration parameters: CountComments.
 Metrics/ModuleLength:
-  Max: 400
+  Max: 370
 
-# Offense count: 1
+# Offense count: 2
 # Configuration parameters: CountKeywordArgs.
 Metrics/ParameterLists:
   Max: 6
 
-# Offense count: 2
-Performance/FixedSize:
-  Exclude:
-    - 'Homebrew/dev-cmd/audit.rb'
-    - 'Homebrew/dev-cmd/bottle.rb'
-
-# Offense count: 8
-Style/AccessorMethodName:
-  Exclude:
-    - 'Homebrew/download_strategy.rb'
-    - 'Homebrew/extend/ENV/std.rb'
-    - 'Homebrew/formula.rb'
-    - 'Homebrew/formula_lock.rb'
-    - 'Homebrew/formulary.rb'
-    - 'Homebrew/migrator.rb'
-
 # Offense count: 1
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, SupportedStyles.
-# SupportedStyles: prefer_alias, prefer_alias_method
-Style/Alias:
-  Exclude:
-    - 'Homebrew/blacklist.rb'
-
-# Offense count: 26
 Style/CaseEquality:
   Exclude:
-    - 'Homebrew/cleanup.rb'
-    - 'Homebrew/cmd/search.rb'
     - 'Homebrew/compilers.rb'
-    - 'Homebrew/cxxstdlib.rb'
-    - 'Homebrew/debrew.rb'
-    - 'Homebrew/dependencies.rb'
-    - 'Homebrew/dependency_collector.rb'
-    - 'Homebrew/download_strategy.rb'
-    - 'Homebrew/formula.rb'
-    - 'Homebrew/options.rb'
-    - 'Homebrew/patch.rb'
-    - 'Homebrew/pkg_version.rb'
-    - 'Homebrew/requirement.rb'
-    - 'Homebrew/requirements.rb'
-    - 'Homebrew/software_spec.rb'
-    - 'Homebrew/version.rb'
-
-# Offense count: 1
-# Cop supports --auto-correct.
-# Configuration parameters: IndentWhenRelativeTo, SupportedStyles, IndentOneStep, IndentationWidth.
-# SupportedStyles: case, end
-Style/CaseIndentation:
-  Exclude:
-    - 'Homebrew/keg.rb'
 
 # Offense count: 11
 Style/ClassVars:
@@ -168,24 +101,6 @@ Style/ConstantName:
   Exclude:
     - 'Homebrew/os/mac.rb'
 
-# Offense count: 10
-Style/DoubleNegation:
-  Exclude:
-    - 'Homebrew/extend/ARGV.rb'
-    - 'Homebrew/formula_installer.rb'
-    - 'Homebrew/os/mac/cctools_keg.rb'
-    - 'Homebrew/os/mac/ruby_keg.rb'
-    - 'Homebrew/os/mac/xcode.rb'
-    - 'Homebrew/requirement.rb'
-    - 'Homebrew/software_spec.rb'
-
-# Offense count: 1
-# Configuration parameters: EnforcedStyle, SupportedStyles.
-# SupportedStyles: format, sprintf, percent
-Style/FormatString:
-  Exclude:
-    - 'Homebrew/formula.rb'
-
 # Offense count: 13
 # Configuration parameters: AllowedVariables.
 Style/GlobalVars:
@@ -193,22 +108,20 @@ Style/GlobalVars:
     - 'Homebrew/diagnostic.rb'
     - 'Homebrew/utils.rb'
 
-# Offense count: 2
-Style/IdenticalConditionalBranches:
+# Offense count: 51
+# Cop supports --auto-correct.
+# Configuration parameters: MaxLineLength.
+Style/IfUnlessModifier:
   Exclude:
-    - 'Homebrew/formula_lock.rb'
+    - 'Taps/**/*'
+    - 'Homebrew/dev-cmd/audit.rb'
 
-# Offense count: 5
-# Configuration parameters: EnforcedStyle, SupportedStyles.
-# SupportedStyles: snake_case, camelCase
-Style/MethodName:
-  Exclude:
-    - 'Homebrew/compat/**/*'
-    - 'Homebrew/cleanup.rb'
-    - 'Homebrew/diagnostic.rb'
-    - 'Homebrew/formula_cellar_checks.rb'
-    - 'Homebrew/formula_installer.rb'
-    - 'Homebrew/os/mac/cctools_mach.rb'
+# Offense count: 2
+# Cop supports --auto-correct.
+# Configuration parameters: SupportedStyles, IndentationWidth.
+# SupportedStyles: special_inside_parentheses, consistent, align_brackets
+Style/IndentArray:
+  EnforcedStyle: special_inside_parentheses
 
 # Offense count: 7
 # Configuration parameters: EnforcedStyle, SupportedStyles.
@@ -219,8 +132,6 @@ Style/ModuleFunction:
     - 'Homebrew/os/mac.rb'
     - 'Homebrew/os/mac/xcode.rb'
     - 'Homebrew/os/mac/xquartz.rb'
-    - 'Homebrew/utils/github.rb'
-    - 'Homebrew/utils/json.rb'
 
 # Offense count: 8
 Style/MultilineBlockChain:
@@ -241,14 +152,6 @@ Style/MutableConstant:
     - 'Homebrew/tab.rb'
     - 'Homebrew/tap.rb'
 
-# Offense count: 1
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, MinBodyLength, SupportedStyles.
-# SupportedStyles: skip_modifier_ifs, always
-Style/Next:
-  Exclude:
-    - 'Homebrew/dev-cmd/test-bot.rb'
-
 # Offense count: 9
 Style/OpMethod:
   Exclude:
@@ -257,37 +160,9 @@ Style/OpMethod:
     - 'Homebrew/install_renamed.rb'
     - 'Homebrew/options.rb'
 
-# Offense count: 4
-# Configuration parameters: NamePrefix, NamePrefixBlacklist, NameWhitelist.
-# NamePrefix: is_, has_, have_
-# NamePrefixBlacklist: is_, has_, have_
-# NameWhitelist: is_a?
-Style/PredicateName:
-  Exclude:
-    - 'Homebrew/compat/**/*'
-    - 'Homebrew/download_strategy.rb'
-    - 'Homebrew/hardware.rb'
-
-# Offense count: 7
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, SupportedStyles, AllowInnerSlashes.
-# SupportedStyles: slashes, percent_r, mixed
-Style/RegexpLiteral:
-  Exclude:
-    - 'Homebrew/diagnostic.rb'
-    - 'Homebrew/keg.rb'
-    - 'Homebrew/version.rb'
-
-# Offense count: 1
+# Offense count: 2
 # Cop supports --auto-correct.
-# Configuration parameters: AllowAsExpressionSeparator.
-Style/Semicolon:
-  Exclude:
-    - 'Homebrew/descriptions.rb'
-
-# Offense count: 1
-# Configuration parameters: Methods.
-# Methods: {"reduce"=>["a", "e"]}, {"inject"=>["a", "e"]}
-Style/SingleLineBlockParams:
-  Exclude:
-    - 'Homebrew/diagnostic.rb'
+# Configuration parameters: SupportedStyles.
+# SupportedStyles: use_perl_names, use_english_names
+Style/SpecialGlobalVars:
+  EnforcedStyle: use_perl_names
diff --git a/Library/Homebrew/test/.simplecov b/Library/Homebrew/.simplecov
index 7b057e878..bc4ed7bb1 100755
--- a/Library/Homebrew/test/.simplecov
+++ b/Library/Homebrew/.simplecov
@@ -1,8 +1,8 @@
 #!/usr/bin/env ruby
 
 SimpleCov.start do
-  coverage_dir File.expand_path("../coverage", File.realpath(__FILE__))
-  root File.expand_path("../..", File.realpath(__FILE__))
+  coverage_dir File.expand_path("../test/coverage", File.realpath(__FILE__))
+  root File.expand_path("..", File.realpath(__FILE__))
 
   # We manage the result cache ourselves and the default of 10 minutes can be
   # too low (particularly on Travis CI), causing results from some integration
@@ -16,14 +16,21 @@ SimpleCov.start do
   add_filter "/Homebrew/vendor/"
 
   if ENV["HOMEBREW_INTEGRATION_TEST"]
-    command_name ENV["HOMEBREW_INTEGRATION_TEST"]
+    command_name "#{ENV["HOMEBREW_INTEGRATION_TEST"]} (#{$$})"
     at_exit do
       exit_code = $!.nil? ? 0 : $!.status
       $stdout.reopen("/dev/null")
-      SimpleCov.result # Just save result, but don't write formatted output.
+
+      # Just save result, but don't write formatted output.
+      coverage_result = Coverage.result
+      SimpleCov.add_not_loaded_files(coverage_result)
+      simplecov_result = SimpleCov::Result.new(coverage_result)
+      SimpleCov::ResultMerger.store_result(simplecov_result)
+
       exit! exit_code
     end
   else
+    command_name "#{command_name} (#{$$})"
     # Not using this during integration tests makes the tests 4x times faster
     # without changing the coverage.
     track_files "#{SimpleCov.root}/**/*.rb"
diff --git a/Library/Homebrew/brew.rb b/Library/Homebrew/brew.rb
index eeadc70e1..1ba3fb8c2 100644
--- a/Library/Homebrew/brew.rb
+++ b/Library/Homebrew/brew.rb
@@ -14,7 +14,7 @@ $:.unshift(HOMEBREW_LIBRARY_PATH.to_s)
 require "global"
 
 if ARGV == %w[--version] || ARGV == %w[-v]
-  puts "Homebrew #{Homebrew.homebrew_version_string}"
+  puts "Homebrew #{HOMEBREW_VERSION}"
   puts "Homebrew/homebrew-core #{Homebrew.core_tap_version_string}"
   exit 0
 end
@@ -37,9 +37,9 @@ begin
   cmd = nil
 
   ARGV.dup.each_with_index do |arg, i|
-    if help_flag && cmd
-      break
-    elsif help_flag_list.include?(arg)
+    break if help_flag && cmd
+
+    if help_flag_list.include?(arg)
       # Option-style help: Both `--help <cmd>` and `<cmd> --help` are fine.
       help_flag = true
     elsif arg == "help" && !cmd
diff --git a/Library/Homebrew/brew.sh b/Library/Homebrew/brew.sh
index fc2e6993c..22ebb87ed 100644
--- a/Library/Homebrew/brew.sh
+++ b/Library/Homebrew/brew.sh
@@ -1,4 +1,8 @@
-HOMEBREW_VERSION="0.9.9"
+HOMEBREW_VERSION="$(git -C "$HOMEBREW_REPOSITORY" describe --tags --dirty 2>/dev/null)"
+if [[ -z "$HOMEBREW_VERSION" ]]
+then
+  HOMEBREW_VERSION=">1.0.0 (no git repository)"
+fi
 
 onoe() {
   if [[ -t 2 ]] # check whether stderr is a tty.
diff --git a/Library/Homebrew/build.rb b/Library/Homebrew/build.rb
index f4dde895a..d3c2833d4 100644
--- a/Library/Homebrew/build.rb
+++ b/Library/Homebrew/build.rb
@@ -31,9 +31,8 @@ class Build
   def post_superenv_hacks
     # Only allow Homebrew-approved directories into the PATH, unless
     # a formula opts-in to allowing the user's path.
-    if formula.env.userpaths? || reqs.any? { |rq| rq.env.userpaths? }
-      ENV.userpaths!
-    end
+    return unless formula.env.userpaths? || reqs.any? { |rq| rq.env.userpaths? }
+    ENV.userpaths!
   end
 
   def effective_build_options_for(dependent)
diff --git a/Library/Homebrew/build_options.rb b/Library/Homebrew/build_options.rb
index 6af3220eb..e9a06f4e0 100644
--- a/Library/Homebrew/build_options.rb
+++ b/Library/Homebrew/build_options.rb
@@ -47,7 +47,7 @@ class BuildOptions
   def bottle?
     include? "build-bottle"
   end
-  alias_method :build_bottle?, :bottle?
+  alias build_bottle? bottle?
 
   # True if a {Formula} is being built with {Formula.head} instead of {Formula.stable}.
   # <pre>args << "--some-new-stuff" if build.head?</pre>
diff --git a/Library/Homebrew/cask/.rubocop.yml b/Library/Homebrew/cask/.rubocop.yml
index 31a2a193d..96a0b0e11 100644
--- a/Library/Homebrew/cask/.rubocop.yml
+++ b/Library/Homebrew/cask/.rubocop.yml
@@ -1,10 +1,8 @@
-require: 'rubocop-cask'
-
 AllCops:
   TargetRubyVersion: 2.0
   Exclude:
+    - '**/.simplecov'
     - '**/Casks/**/*'
-    - 'developer/**/*'
     - '**/vendor/**/*'
 
 Metrics/AbcSize:
@@ -16,10 +14,10 @@ Metrics/ClassLength:
 Metrics/CyclomaticComplexity:
   Enabled: false
 
-Metrics/MethodLength:
+Metrics/LineLength:
   Enabled: false
 
-Metrics/PerceivedComplexity:
+Metrics/MethodLength:
   Enabled: false
 
 Metrics/ModuleLength:
@@ -29,6 +27,16 @@ Metrics/ModuleLength:
     - 'lib/hbc/macos.rb'
     - 'lib/hbc/utils.rb'
 
+Metrics/PerceivedComplexity:
+  Enabled: false
+
+Style/AlignHash:
+  EnforcedHashRocketStyle: table
+  EnforcedColonStyle: table
+
+Style/BarePercentLiterals:
+  EnforcedStyle: percent_q
+
 Style/BlockDelimiters:
   EnforcedStyle: semantic
   FunctionalMethods:
@@ -59,6 +67,8 @@ Style/BlockDelimiters:
     - chdir
     - context
     - create
+    - define_method
+    - define_singleton_method
     - each_with_object
     - fork
     - measure
@@ -75,15 +85,47 @@ Style/BlockDelimiters:
     - lambda
     - proc
 
-
 Style/ClassAndModuleChildren:
-  EnforcedStyle: compact
+  EnforcedStyle: nested
 
-Style/PredicateName:
-  NameWhitelist: is_32_bit?, is_64_bit?
+Style/Documentation:
+  Enabled: false
+
+Style/FileName:
+  Regex: !ruby/regexp /^((([\dA-Z]+|[\da-z]+)(_([\dA-Z]+|[\da-z]+))*|(\-\-)?([\dA-Z]+|[\da-z]+)(-([\dA-Z]+|[\da-z]+))*))(\.rb)?$/
+
+Style/HashSyntax:
+  EnforcedStyle: ruby19_no_mixed_keys
+
+Style/IndentArray:
+  EnforcedStyle: align_brackets
+
+Style/IndentHash:
+  EnforcedStyle: align_braces
+
+Style/PercentLiteralDelimiters:
+  PreferredDelimiters:
+    '%':  '{}'
+    '%i': '{}'
+    '%q': '{}'
+    '%Q': '{}'
+    '%r': '{}'
+    '%s': '()'
+    '%w': '[]'
+    '%W': '[]'
+    '%x': '()'
 
 Style/RaiseArgs:
   EnforcedStyle: exploded
 
+Style/RegexpLiteral:
+  EnforcedStyle: percent_r
+
 Style/StringLiterals:
   EnforcedStyle: double_quotes
+
+Style/StringLiteralsInInterpolation:
+  EnforcedStyle: double_quotes
+
+Style/TrailingCommaInLiteral:
+  EnforcedStyleForMultiline: comma
diff --git a/Library/Homebrew/cask/.simplecov b/Library/Homebrew/cask/.simplecov
index d1b045262..75a078be4 120000
--- a/Library/Homebrew/cask/.simplecov
+++ b/Library/Homebrew/cask/.simplecov
@@ -1 +1 @@
-../test/.simplecov
\ No newline at end of file
+../.simplecov
\ No newline at end of file
diff --git a/Library/Homebrew/cask/Gemfile b/Library/Homebrew/cask/Gemfile
index af1c8d3bc..df06bd5d4 100644
--- a/Library/Homebrew/cask/Gemfile
+++ b/Library/Homebrew/cask/Gemfile
@@ -7,15 +7,21 @@ group :debug do
   gem "pry-byebug", platforms: :mri
 end
 
-group :development do
-  gem "rubocop-cask", "~> 0.8.3"
-end
-
 group :test do
+  # This is SimpleCov v0.12.0 with two fixes merged on top, that finally resolve
+  # all issues with parallel tests, uncovered files, and tracked files. Switch
+  # back to stable as soon as v0.12.1 or v0.13.0 is released. For details, see:
+  #  - https://github.com/colszowka/simplecov/pull/513
+  #  - https://github.com/colszowka/simplecov/pull/520
+  gem "simplecov", "0.12.0",
+    git: "https://github.com/colszowka/simplecov.git",
+    branch: "master", # commit 83d8031ddde0927f87ef9327200a98583ca18d77
+    require: false
   gem "codecov", require: false
   gem "minitest", "5.4.1"
   gem "minitest-reporters"
   gem "mocha", "1.1.0", require: false
+  gem "parallel_tests"
   gem "rspec", "~> 3.0.0"
   gem "rspec-its", require: false
   gem "rspec-wait", require: false
diff --git a/Library/Homebrew/cask/Gemfile.lock b/Library/Homebrew/cask/Gemfile.lock
index c9c2b5cca..93dd59712 100644
--- a/Library/Homebrew/cask/Gemfile.lock
+++ b/Library/Homebrew/cask/Gemfile.lock
@@ -1,8 +1,17 @@
+GIT
+  remote: https://github.com/colszowka/simplecov.git
+  revision: 83d8031ddde0927f87ef9327200a98583ca18d77
+  branch: master
+  specs:
+    simplecov (0.12.0)
+      docile (~> 1.1.0)
+      json (>= 1.8, < 3)
+      simplecov-html (~> 0.10.0)
+
 GEM
   remote: https://rubygems.org/
   specs:
     ansi (1.5.0)
-    ast (2.3.0)
     builder (3.2.2)
     byebug (9.0.5)
     codecov (0.1.5)
@@ -23,9 +32,9 @@ GEM
       ruby-progressbar
     mocha (1.1.0)
       metaclass (~> 0.0.1)
-    parser (2.3.1.2)
-      ast (~> 2.2)
-    powerpack (0.1.1)
+    parallel (1.9.0)
+    parallel_tests (2.9.0)
+      parallel
     pry (0.10.4)
       coderay (~> 1.1.0)
       method_source (~> 0.8.1)
@@ -33,8 +42,6 @@ GEM
     pry-byebug (3.4.0)
       byebug (~> 9.0)
       pry (~> 0.10)
-    public_suffix (2.0.2)
-    rainbow (2.1.0)
     rake (10.4.2)
     rspec (3.0.0)
       rspec-core (~> 3.0.0)
@@ -53,23 +60,9 @@ GEM
     rspec-support (3.0.4)
     rspec-wait (0.0.9)
       rspec (>= 3, < 4)
-    rubocop (0.41.2)
-      parser (>= 2.3.1.1, < 3.0)
-      powerpack (~> 0.1)
-      rainbow (>= 1.99.1, < 3.0)
-      ruby-progressbar (~> 1.7)
-      unicode-display_width (~> 1.0, >= 1.0.1)
-    rubocop-cask (0.8.3)
-      public_suffix (~> 2.0)
-      rubocop (~> 0.41.1)
     ruby-progressbar (1.8.1)
-    simplecov (0.12.0)
-      docile (~> 1.1.0)
-      json (>= 1.8, < 3)
-      simplecov-html (~> 0.10.0)
     simplecov-html (0.10.0)
     slop (3.6.0)
-    unicode-display_width (1.1.0)
     url (0.3.2)
 
 PLATFORMS
@@ -80,13 +73,14 @@ DEPENDENCIES
   minitest (= 5.4.1)
   minitest-reporters
   mocha (= 1.1.0)
+  parallel_tests
   pry
   pry-byebug
   rake
   rspec (~> 3.0.0)
   rspec-its
   rspec-wait
-  rubocop-cask (~> 0.8.3)
+  simplecov (= 0.12.0)!
 
 BUNDLED WITH
-   1.12.5
+   1.13.1
diff --git a/Library/Homebrew/cask/Rakefile b/Library/Homebrew/cask/Rakefile
index 25deee407..ec6a4a7f6 100644
--- a/Library/Homebrew/cask/Rakefile
+++ b/Library/Homebrew/cask/Rakefile
@@ -1,29 +1,14 @@
 require "rake/testtask"
 require "rspec/core/rake_task"
-require "rubocop/rake_task"
 
 homebrew_repo = `brew --repository`.chomp
 $LOAD_PATH.unshift(File.expand_path("#{homebrew_repo}/Library/Homebrew"))
 $LOAD_PATH.unshift(File.expand_path("../lib", __FILE__))
 
 namespace :test do
-  Rake::TestTask.new(:minitest) do |t|
-    # TODO: setting the --seed here is an ugly temporary hack, to remain only
-    #       until test-suite glitches are fixed.
-    ENV["TESTOPTS"] = "--seed=14830" if ENV["TRAVIS"]
-    t.pattern = "test/**/*_test.rb"
-    t.libs << "test"
-  end
-
-  RSpec::Core::RakeTask.new(:rspec)
-
-  desc "Run tests for minitest and RSpec with coverage"
-  task :coverage do
-    ENV["HOMEBREW_TESTS_COVERAGE"] = "1"
-
-    Rake::Task[:test].invoke
-
-    if ENV["CODECOV_TOKEN"]
+  namespace :coverage do
+    desc "Upload coverage to Codecov"
+    task :upload do
       require "simplecov"
       require "codecov"
       formatter = SimpleCov::Formatter::Codecov.new
@@ -32,15 +17,6 @@ namespace :test do
   end
 end
 
-desc "Run tests for minitest and RSpec"
-task test: ["test:minitest", "test:rspec"]
-
-RuboCop::RakeTask.new(:rubocop) do |t|
-  t.options = ["--force-exclusion"]
-end
-
-task default: [:test, :rubocop]
-
 desc "Open a REPL for debugging and experimentation"
 task :console do
   require "pry"
diff --git a/Library/Homebrew/cask/cmd/brew-cask-tests.rb b/Library/Homebrew/cask/cmd/brew-cask-tests.rb
index 92ef3ddd9..7ae71020e 100755
--- a/Library/Homebrew/cask/cmd/brew-cask-tests.rb
+++ b/Library/Homebrew/cask/cmd/brew-cask-tests.rb
@@ -1,5 +1,12 @@
 require "English"
 
+def run_tests(executable, files, args = [])
+  opts = []
+  opts << "--serialize-stdout" if ENV["CI"]
+
+  system "bundle", "exec", executable, *opts, "--", *args, "--", *files
+end
+
 repo_root = Pathname(__FILE__).realpath.parent.parent
 repo_root.cd do
   ENV["HOMEBREW_NO_ANALYTICS_THIS_RUN"] = "1"
@@ -9,12 +16,26 @@ repo_root.cd do
     system "bundle", "install", "--path", "vendor/bundle"
   end
 
-  test_task = "test"
-  %w[rspec minitest coverage].each do |subtask|
-    next unless ARGV.flag?("--#{subtask}")
-    test_task = "test:#{subtask}"
+  rspec = ARGV.flag?("--rspec") || !ARGV.flag?("--minitest")
+  minitest = ARGV.flag?("--minitest") || !ARGV.flag?("--rspec")
+
+  ENV["HOMEBREW_TESTS_COVERAGE"] = "1" if ARGV.flag?("--coverage")
+
+  if rspec
+    run_tests "parallel_rspec", Dir["spec/**/*_spec.rb"], %w[
+      --format progress
+      --format ParallelTests::RSpec::RuntimeLogger
+      --out tmp/parallel_runtime_rspec.log
+    ]
+  end
+
+  if minitest
+    run_tests "parallel_test", Dir["test/**/*_test.rb"]
+  end
+
+  if ENV["CODECOV_TOKEN"]
+    system "bundle", "exec", "rake", "test:coverage:upload"
   end
 
-  system "bundle", "exec", "rake", test_task
   Homebrew.failed = !$CHILD_STATUS.success?
 end
diff --git a/Library/Homebrew/cask/lib/hbc.rb b/Library/Homebrew/cask/lib/hbc.rb
index fd61558ab..62b391638 100644
--- a/Library/Homebrew/cask/lib/hbc.rb
+++ b/Library/Homebrew/cask/lib/hbc.rb
@@ -40,22 +40,22 @@ require "utils"
 require "vendor/plist/plist"
 
 module Hbc
-  include Hbc::Locations
-  include Hbc::Scopes
-  include Hbc::Options
-  include Hbc::Utils
+  include Locations
+  include Scopes
+  include Options
+  include Utils
 
   def self.init
-    Hbc::Cache.ensure_cache_exists
-    Hbc::Cache.migrate_legacy_cache
+    Cache.ensure_cache_exists
+    Cache.migrate_legacy_cache
 
-    Hbc::Caskroom.migrate_caskroom_from_repo_to_prefix
-    Hbc::Caskroom.ensure_caskroom_exists
+    Caskroom.migrate_caskroom_from_repo_to_prefix
+    Caskroom.ensure_caskroom_exists
   end
 
   def self.load(query)
     odebug "Loading Cask definitions"
-    cask = Hbc::Source.for_query(query).load
+    cask = Source.for_query(query).load
     cask.dumpcask
     cask
   end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact.rb b/Library/Homebrew/cask/lib/hbc/artifact.rb
index 73bd582a5..ec808a614 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact.rb
@@ -1,5 +1,3 @@
-module Hbc::Artifact; end
-
 require "hbc/artifact/app"
 require "hbc/artifact/artifact" # generic 'artifact' stanza
 require "hbc/artifact/binary"
@@ -24,42 +22,44 @@ require "hbc/artifact/suite"
 require "hbc/artifact/uninstall"
 require "hbc/artifact/zap"
 
-module Hbc::Artifact
-  # NOTE: order is important here, since we want to extract nested containers
-  #       before we handle any other artifacts
-  def self.artifacts
-    [
-      Hbc::Artifact::PreflightBlock,
-      Hbc::Artifact::NestedContainer,
-      Hbc::Artifact::Installer,
-      Hbc::Artifact::App,
-      Hbc::Artifact::Suite,
-      Hbc::Artifact::Artifact, # generic 'artifact' stanza
-      Hbc::Artifact::Colorpicker,
-      Hbc::Artifact::Pkg,
-      Hbc::Artifact::Prefpane,
-      Hbc::Artifact::Qlplugin,
-      Hbc::Artifact::Font,
-      Hbc::Artifact::Service,
-      Hbc::Artifact::StageOnly,
-      Hbc::Artifact::Binary,
-      Hbc::Artifact::InputMethod,
-      Hbc::Artifact::InternetPlugin,
-      Hbc::Artifact::AudioUnitPlugin,
-      Hbc::Artifact::VstPlugin,
-      Hbc::Artifact::Vst3Plugin,
-      Hbc::Artifact::ScreenSaver,
-      Hbc::Artifact::Uninstall,
-      Hbc::Artifact::PostflightBlock,
-      Hbc::Artifact::Zap,
-    ]
-  end
+module Hbc
+  module Artifact
+    # NOTE: order is important here, since we want to extract nested containers
+    #       before we handle any other artifacts
+    def self.artifacts
+      [
+        PreflightBlock,
+        NestedContainer,
+        Installer,
+        App,
+        Suite,
+        Artifact, # generic 'artifact' stanza
+        Colorpicker,
+        Pkg,
+        Prefpane,
+        Qlplugin,
+        Font,
+        Service,
+        StageOnly,
+        Binary,
+        InputMethod,
+        InternetPlugin,
+        AudioUnitPlugin,
+        VstPlugin,
+        Vst3Plugin,
+        ScreenSaver,
+        Uninstall,
+        PostflightBlock,
+        Zap,
+      ]
+    end
 
-  def self.for_cask(cask)
-    odebug "Determining which artifacts are present in Cask #{cask}"
-    artifacts.select do |artifact|
-      odebug "Checking for artifact class #{artifact}"
-      artifact.me?(cask)
+    def self.for_cask(cask)
+      odebug "Determining which artifacts are present in Cask #{cask}"
+      artifacts.select do |artifact|
+        odebug "Checking for artifact class #{artifact}"
+        artifact.me?(cask)
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/abstract_flight_block.rb b/Library/Homebrew/cask/lib/hbc/artifact/abstract_flight_block.rb
index fcf98d7ad..30709a0b5 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/abstract_flight_block.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/abstract_flight_block.rb
@@ -1,36 +1,40 @@
 require "hbc/artifact/base"
 
-class Hbc::Artifact::AbstractFlightBlock < Hbc::Artifact::Base
-  def self.artifact_dsl_key
-    super.to_s.sub(%r{_block$}, "").to_sym
-  end
-
-  def self.uninstall_artifact_dsl_key
-    artifact_dsl_key.to_s.prepend("uninstall_").to_sym
-  end
-
-  def self.class_for_dsl_key(dsl_key)
-    Object.const_get("Hbc::DSL::#{dsl_key.to_s.split('_').collect(&:capitalize).join}")
-  end
-
-  def self.me?(cask)
-    cask.artifacts[artifact_dsl_key].any? ||
-      cask.artifacts[uninstall_artifact_dsl_key].any?
-  end
-
-  def install_phase
-    abstract_phase(self.class.artifact_dsl_key)
-  end
-
-  def uninstall_phase
-    abstract_phase(self.class.uninstall_artifact_dsl_key)
-  end
-
-  private
-
-  def abstract_phase(dsl_key)
-    @cask.artifacts[dsl_key].each do |block|
-      self.class.class_for_dsl_key(dsl_key).new(@cask).instance_eval(&block)
+module Hbc
+  module Artifact
+    class AbstractFlightBlock < Base
+      def self.artifact_dsl_key
+        super.to_s.sub(%r{_block$}, "").to_sym
+      end
+
+      def self.uninstall_artifact_dsl_key
+        artifact_dsl_key.to_s.prepend("uninstall_").to_sym
+      end
+
+      def self.class_for_dsl_key(dsl_key)
+        Object.const_get("Hbc::DSL::#{dsl_key.to_s.split("_").collect(&:capitalize).join}")
+      end
+
+      def self.me?(cask)
+        cask.artifacts[artifact_dsl_key].any? ||
+          cask.artifacts[uninstall_artifact_dsl_key].any?
+      end
+
+      def install_phase
+        abstract_phase(self.class.artifact_dsl_key)
+      end
+
+      def uninstall_phase
+        abstract_phase(self.class.uninstall_artifact_dsl_key)
+      end
+
+      private
+
+      def abstract_phase(dsl_key)
+        @cask.artifacts[dsl_key].each do |block|
+          self.class.class_for_dsl_key(dsl_key).new(@cask).instance_eval(&block)
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/app.rb b/Library/Homebrew/cask/lib/hbc/artifact/app.rb
index bbda16f74..cc6ef61a7 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/app.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/app.rb
@@ -1,4 +1,8 @@
 require "hbc/artifact/moved"
 
-class Hbc::Artifact::App < Hbc::Artifact::Moved
+module Hbc
+  module Artifact
+    class App < Moved
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/artifact.rb b/Library/Homebrew/cask/lib/hbc/artifact/artifact.rb
index e2c06eb70..cb35821cc 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/artifact.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/artifact.rb
@@ -1,20 +1,24 @@
 require "hbc/artifact/moved"
 
-class Hbc::Artifact::Artifact < Hbc::Artifact::Moved
-  def self.artifact_english_name
-    "Generic Artifact"
-  end
+module Hbc
+  module Artifact
+    class Artifact < Moved
+      def self.artifact_english_name
+        "Generic Artifact"
+      end
 
-  def self.artifact_dirmethod
-    :appdir
-  end
+      def self.artifact_dirmethod
+        :appdir
+      end
 
-  def load_specification(artifact_spec)
-    source_string, target_hash = artifact_spec
-    raise Hbc::CaskInvalidError.new(@cask.token, "no source given for artifact") if source_string.nil?
-    @source = @cask.staged_path.join(source_string)
-    raise Hbc::CaskInvalidError.new(@cask.token, "target required for generic artifact #{source_string}") unless target_hash.is_a?(Hash)
-    target_hash.assert_valid_keys(:target)
-    @target = Pathname.new(target_hash[:target])
+      def load_specification(artifact_spec)
+        source_string, target_hash = artifact_spec
+        raise CaskInvalidError.new(@cask.token, "no source given for artifact") if source_string.nil?
+        @source = @cask.staged_path.join(source_string)
+        raise CaskInvalidError.new(@cask.token, "target required for generic artifact #{source_string}") unless target_hash.is_a?(Hash)
+        target_hash.assert_valid_keys(:target)
+        @target = Pathname.new(target_hash[:target])
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/audio_unit_plugin.rb b/Library/Homebrew/cask/lib/hbc/artifact/audio_unit_plugin.rb
index 7f3999306..3bad78073 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/audio_unit_plugin.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/audio_unit_plugin.rb
@@ -1,4 +1,8 @@
 require "hbc/artifact/moved"
 
-class Hbc::Artifact::AudioUnitPlugin < Hbc::Artifact::Moved
+module Hbc
+  module Artifact
+    class AudioUnitPlugin < Moved
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/base.rb b/Library/Homebrew/cask/lib/hbc/artifact/base.rb
index 9a07cc906..141ab6881 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/base.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/base.rb
@@ -1,79 +1,83 @@
-class Hbc::Artifact::Base
-  def self.artifact_name
-    @artifact_name ||= name.sub(%r{^.*:}, "").gsub(%r{(.)([A-Z])}, '\1_\2').downcase
-  end
-
-  def self.artifact_english_name
-    @artifact_english_name ||= name.sub(%r{^.*:}, "").gsub(%r{(.)([A-Z])}, '\1 \2')
-  end
-
-  def self.artifact_english_article
-    @artifact_english_article ||= artifact_english_name =~ %r{^[aeiou]}i ? "an" : "a"
-  end
-
-  def self.artifact_dsl_key
-    @artifact_dsl_key ||= artifact_name.to_sym
-  end
-
-  def self.artifact_dirmethod
-    @artifact_dirmethod ||= "#{artifact_name}dir".to_sym
-  end
-
-  def self.me?(cask)
-    cask.artifacts[artifact_dsl_key].any?
-  end
-
-  attr_reader :force
-
-  def zap_phase
-    odebug "Nothing to do. The #{self.class.artifact_name} artifact has no zap phase."
-  end
-
-  # TODO: this sort of logic would make more sense in dsl.rb, or a
-  #       constructor called from dsl.rb, so long as that isn't slow.
-  def self.read_script_arguments(arguments, stanza, default_arguments = {}, override_arguments = {}, key = nil)
-    # TODO: when stanza names are harmonized with class names,
-    #       stanza may not be needed as an explicit argument
-    description = stanza.to_s
-    if key
-      arguments = arguments[key]
-      description.concat(" #{key.inspect}")
-    end
-
-    # backward-compatible string value
-    arguments = { executable: arguments } if arguments.is_a?(String)
-
-    # key sanity
-    permitted_keys = [:args, :input, :executable, :must_succeed, :sudo, :bsexec, :print_stdout, :print_stderr]
-    unknown_keys = arguments.keys - permitted_keys
-    unless unknown_keys.empty?
-      opoo %Q{Unknown arguments to #{description} -- #{unknown_keys.inspect} (ignored). Running "brew update; brew cleanup; brew cask cleanup" will likely fix it.}
+module Hbc
+  module Artifact
+    class Base
+      def self.artifact_name
+        @artifact_name ||= name.sub(%r{^.*:}, "").gsub(%r{(.)([A-Z])}, '\1_\2').downcase
+      end
+
+      def self.artifact_english_name
+        @artifact_english_name ||= name.sub(%r{^.*:}, "").gsub(%r{(.)([A-Z])}, '\1 \2')
+      end
+
+      def self.artifact_english_article
+        @artifact_english_article ||= artifact_english_name =~ %r{^[aeiou]}i ? "an" : "a"
+      end
+
+      def self.artifact_dsl_key
+        @artifact_dsl_key ||= artifact_name.to_sym
+      end
+
+      def self.artifact_dirmethod
+        @artifact_dirmethod ||= "#{artifact_name}dir".to_sym
+      end
+
+      def self.me?(cask)
+        cask.artifacts[artifact_dsl_key].any?
+      end
+
+      attr_reader :force
+
+      def zap_phase
+        odebug "Nothing to do. The #{self.class.artifact_name} artifact has no zap phase."
+      end
+
+      # TODO: this sort of logic would make more sense in dsl.rb, or a
+      #       constructor called from dsl.rb, so long as that isn't slow.
+      def self.read_script_arguments(arguments, stanza, default_arguments = {}, override_arguments = {}, key = nil)
+        # TODO: when stanza names are harmonized with class names,
+        #       stanza may not be needed as an explicit argument
+        description = stanza.to_s
+        if key
+          arguments = arguments[key]
+          description.concat(" #{key.inspect}")
+        end
+
+        # backward-compatible string value
+        arguments = { executable: arguments } if arguments.is_a?(String)
+
+        # key sanity
+        permitted_keys = [:args, :input, :executable, :must_succeed, :sudo, :bsexec, :print_stdout, :print_stderr]
+        unknown_keys = arguments.keys - permitted_keys
+        unless unknown_keys.empty?
+          opoo %Q{Unknown arguments to #{description} -- #{unknown_keys.inspect} (ignored). Running "brew update; brew cleanup; brew cask cleanup" will likely fix it.}
+        end
+        arguments.reject! { |k| !permitted_keys.include?(k) }
+
+        # key warnings
+        override_keys = override_arguments.keys
+        ignored_keys = arguments.keys & override_keys
+        unless ignored_keys.empty?
+          onoe "Some arguments to #{description} will be ignored -- :#{unknown_keys.inspect} (overridden)."
+        end
+
+        # extract executable
+        executable = arguments.key?(:executable) ? arguments.delete(:executable) : nil
+
+        arguments = default_arguments.merge arguments
+        arguments.merge! override_arguments
+
+        [executable, arguments]
+      end
+
+      def summary
+        {}
+      end
+
+      def initialize(cask, command: SystemCommand, force: false)
+        @cask = cask
+        @command = command
+        @force = force
+      end
     end
-    arguments.reject! { |k| !permitted_keys.include?(k) }
-
-    # key warnings
-    override_keys = override_arguments.keys
-    ignored_keys = arguments.keys & override_keys
-    unless ignored_keys.empty?
-      onoe "Some arguments to #{description} will be ignored -- :#{unknown_keys.inspect} (overridden)."
-    end
-
-    # extract executable
-    executable = arguments.key?(:executable) ? arguments.delete(:executable) : nil
-
-    arguments = default_arguments.merge arguments
-    arguments.merge! override_arguments
-
-    [executable, arguments]
-  end
-
-  def summary
-    {}
-  end
-
-  def initialize(cask, command: Hbc::SystemCommand, force: false)
-    @cask = cask
-    @command = command
-    @force = force
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/binary.rb b/Library/Homebrew/cask/lib/hbc/artifact/binary.rb
index ccaebe0c8..646e5c3ad 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/binary.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/binary.rb
@@ -1,7 +1,11 @@
 require "hbc/artifact/symlinked"
 
-class Hbc::Artifact::Binary < Hbc::Artifact::Symlinked
-  def install_phase
-    super unless Hbc.no_binaries
+module Hbc
+  module Artifact
+    class Binary < Symlinked
+      def install_phase
+        super unless Hbc.no_binaries
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/colorpicker.rb b/Library/Homebrew/cask/lib/hbc/artifact/colorpicker.rb
index 7b56d0ffc..a866e64a5 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/colorpicker.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/colorpicker.rb
@@ -1,4 +1,8 @@
 require "hbc/artifact/moved"
 
-class Hbc::Artifact::Colorpicker < Hbc::Artifact::Moved
+module Hbc
+  module Artifact
+    class Colorpicker < Moved
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/font.rb b/Library/Homebrew/cask/lib/hbc/artifact/font.rb
index 9697d9e13..5c64869b6 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/font.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/font.rb
@@ -1,4 +1,8 @@
 require "hbc/artifact/moved"
 
-class Hbc::Artifact::Font < Hbc::Artifact::Moved
+module Hbc
+  module Artifact
+    class Font < Moved
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/input_method.rb b/Library/Homebrew/cask/lib/hbc/artifact/input_method.rb
index 3c7f3d990..0eb75a6c0 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/input_method.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/input_method.rb
@@ -1,4 +1,8 @@
 require "hbc/artifact/moved"
 
-class Hbc::Artifact::InputMethod < Hbc::Artifact::Moved
+module Hbc
+  module Artifact
+    class InputMethod < Moved
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/installer.rb b/Library/Homebrew/cask/lib/hbc/artifact/installer.rb
index 2f66397e9..b64b00fe3 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/installer.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/installer.rb
@@ -1,41 +1,45 @@
 require "hbc/artifact/base"
 
-class Hbc::Artifact::Installer < Hbc::Artifact::Base
-  # TODO: for backward compatibility, removeme
-  def install
-    install_phase
-  end
+module Hbc
+  module Artifact
+    class Installer < Base
+      # TODO: for backward compatibility, removeme
+      def install
+        install_phase
+      end
 
-  # TODO: for backward compatibility, removeme
-  def uninstall
-    uninstall_phase
-  end
+      # TODO: for backward compatibility, removeme
+      def uninstall
+        uninstall_phase
+      end
 
-  def install_phase
-    @cask.artifacts[self.class.artifact_dsl_key].each do |artifact|
-      if artifact.manual
-        puts <<-EOS.undent
-          To complete the installation of Cask #{@cask}, you must also
-          run the installer at
+      def install_phase
+        @cask.artifacts[self.class.artifact_dsl_key].each do |artifact|
+          if artifact.manual
+            puts <<-EOS.undent
+              To complete the installation of Cask #{@cask}, you must also
+              run the installer at
 
-            '#{@cask.staged_path.join(artifact.manual)}'
+                '#{@cask.staged_path.join(artifact.manual)}'
 
-        EOS
-      else
-        executable, script_arguments = self.class.read_script_arguments(artifact.script,
-                                                                        self.class.artifact_dsl_key.to_s,
-                                                                        { must_succeed: true, sudo: true },
-                                                                        print_stdout: true)
-        ohai "Running #{self.class.artifact_dsl_key} script #{executable}"
-        raise Hbc::CaskInvalidError.new(@cask, "#{self.class.artifact_dsl_key} missing executable") if executable.nil?
-        executable_path = @cask.staged_path.join(executable)
-        @command.run("/bin/chmod", args: ["--", "+x", executable_path]) if File.exist?(executable_path)
-        @command.run(executable_path, script_arguments)
+            EOS
+          else
+            executable, script_arguments = self.class.read_script_arguments(artifact.script,
+                                                                            self.class.artifact_dsl_key.to_s,
+                                                                            { must_succeed: true, sudo: true },
+                                                                            print_stdout: true)
+            ohai "Running #{self.class.artifact_dsl_key} script #{executable}"
+            raise CaskInvalidError.new(@cask, "#{self.class.artifact_dsl_key} missing executable") if executable.nil?
+            executable_path = @cask.staged_path.join(executable)
+            @command.run("/bin/chmod", args: ["--", "+x", executable_path]) if File.exist?(executable_path)
+            @command.run(executable_path, script_arguments)
+          end
+        end
       end
-    end
-  end
 
-  def uninstall_phase
-    odebug "Nothing to do. The #{self.class.artifact_dsl_key} artifact has no uninstall phase."
+      def uninstall_phase
+        odebug "Nothing to do. The #{self.class.artifact_dsl_key} artifact has no uninstall phase."
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/internet_plugin.rb b/Library/Homebrew/cask/lib/hbc/artifact/internet_plugin.rb
index a44418274..ab8586d69 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/internet_plugin.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/internet_plugin.rb
@@ -1,4 +1,8 @@
 require "hbc/artifact/moved"
 
-class Hbc::Artifact::InternetPlugin < Hbc::Artifact::Moved
+module Hbc
+  module Artifact
+    class InternetPlugin < Moved
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/moved.rb b/Library/Homebrew/cask/lib/hbc/artifact/moved.rb
index 8565ab836..6095887e3 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/moved.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/moved.rb
@@ -1,88 +1,92 @@
 require "hbc/artifact/relocated"
 
-class Hbc::Artifact::Moved < Hbc::Artifact::Relocated
-  def self.english_description
-    "#{artifact_english_name}s"
-  end
+module Hbc
+  module Artifact
+    class Moved < Relocated
+      def self.english_description
+        "#{artifact_english_name}s"
+      end
 
-  def install_phase
-    each_artifact do |artifact|
-      load_specification(artifact)
-      next unless preflight_checks
-      delete if Hbc::Utils.path_occupied?(target) && force
-      move
-    end
-  end
+      def install_phase
+        each_artifact do |artifact|
+          load_specification(artifact)
+          next unless preflight_checks
+          delete if Utils.path_occupied?(target) && force
+          move
+        end
+      end
 
-  def uninstall_phase
-    each_artifact do |artifact|
-      load_specification(artifact)
-      next unless File.exist?(target)
-      delete
-    end
-  end
+      def uninstall_phase
+        each_artifact do |artifact|
+          load_specification(artifact)
+          next unless File.exist?(target)
+          delete
+        end
+      end
 
-  private
+      private
 
-  def each_artifact
-    # the sort is for predictability between Ruby versions
-    @cask.artifacts[self.class.artifact_dsl_key].sort.each do |artifact|
-      yield artifact
-    end
-  end
+      def each_artifact
+        # the sort is for predictability between Ruby versions
+        @cask.artifacts[self.class.artifact_dsl_key].sort.each do |artifact|
+          yield artifact
+        end
+      end
 
-  def move
-    ohai "Moving #{self.class.artifact_english_name} '#{source.basename}' to '#{target}'"
-    target.dirname.mkpath
-    FileUtils.move(source, target)
-    add_altname_metadata target, source.basename.to_s
-  end
+      def move
+        ohai "Moving #{self.class.artifact_english_name} '#{source.basename}' to '#{target}'"
+        target.dirname.mkpath
+        FileUtils.move(source, target)
+        add_altname_metadata target, source.basename.to_s
+      end
 
-  def preflight_checks
-    if Hbc::Utils.path_occupied?(target)
-      if force
-        ohai(warning_target_exists { |s| s << "overwriting." })
-      else
-        ohai(warning_target_exists { |s| s << "not moving." })
-        return false
+      def preflight_checks
+        if Utils.path_occupied?(target)
+          if force
+            ohai(warning_target_exists { |s| s << "overwriting." })
+          else
+            ohai(warning_target_exists { |s| s << "not moving." })
+            return false
+          end
+        end
+        unless source.exist?
+          message = "It seems the #{self.class.artifact_english_name} source is not there: '#{source}'"
+          raise CaskError, message
+        end
+        true
       end
-    end
-    unless source.exist?
-      message = "It seems the #{self.class.artifact_english_name} source is not there: '#{source}'"
-      raise Hbc::CaskError, message
-    end
-    true
-  end
 
-  def warning_target_exists
-    message_parts = [
-                      "It seems there is already #{self.class.artifact_english_article} #{self.class.artifact_english_name} at '#{target}'",
-                    ]
-    yield(message_parts) if block_given?
-    message_parts.join("; ")
-  end
+      def warning_target_exists
+        message_parts = [
+                          "It seems there is already #{self.class.artifact_english_article} #{self.class.artifact_english_name} at '#{target}'",
+                        ]
+        yield(message_parts) if block_given?
+        message_parts.join("; ")
+      end
 
-  def delete
-    ohai "Removing #{self.class.artifact_english_name}: '#{target}'"
-    if MacOS.undeletable?(target)
-      raise Hbc::CaskError, "Cannot remove undeletable #{self.class.artifact_english_name}"
-    elsif force
-      Hbc::Utils.gain_permissions_remove(target, command: @command)
-    else
-      target.rmtree
-    end
-  end
+      def delete
+        ohai "Removing #{self.class.artifact_english_name}: '#{target}'"
+        raise CaskError, "Cannot remove undeletable #{self.class.artifact_english_name}" if MacOS.undeletable?(target)
 
-  def summarize_artifact(artifact_spec)
-    load_specification artifact_spec
+        if force
+          Utils.gain_permissions_remove(target, command: @command)
+        else
+          target.rmtree
+        end
+      end
 
-    if target.exist?
-      target_abv = " (#{target.abv})"
-    else
-      warning = "Missing #{self.class.artifact_english_name}"
-      warning = "#{Tty.red}#{warning}#{Tty.reset}: "
-    end
+      def summarize_artifact(artifact_spec)
+        load_specification artifact_spec
 
-    "#{warning}#{printable_target}#{target_abv}"
+        if target.exist?
+          target_abv = " (#{target.abv})"
+        else
+          warning = "Missing #{self.class.artifact_english_name}"
+          warning = "#{Tty.red}#{warning}#{Tty.reset}: "
+        end
+
+        "#{warning}#{printable_target}#{target_abv}"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/nested_container.rb b/Library/Homebrew/cask/lib/hbc/artifact/nested_container.rb
index 68e4a552c..107640797 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/nested_container.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/nested_container.rb
@@ -1,24 +1,28 @@
 require "hbc/artifact/base"
 
-class Hbc::Artifact::NestedContainer < Hbc::Artifact::Base
-  def install_phase
-    @cask.artifacts[:nested_container].each { |container| extract(container) }
-  end
+module Hbc
+  module Artifact
+    class NestedContainer < Base
+      def install_phase
+        @cask.artifacts[:nested_container].each { |container| extract(container) }
+      end
 
-  def uninstall_phase
-    # no need to take action; is removed after extraction
-  end
+      def uninstall_phase
+        # no need to take action; is removed after extraction
+      end
 
-  def extract(container_relative_path)
-    source = @cask.staged_path.join(container_relative_path)
-    container = Hbc::Container.for_path(source, @command)
+      def extract(container_relative_path)
+        source = @cask.staged_path.join(container_relative_path)
+        container = Container.for_path(source, @command)
 
-    unless container
-      raise Hbc::CaskError, "Aw dang, could not identify nested container at '#{source}'"
-    end
+        unless container
+          raise CaskError, "Aw dang, could not identify nested container at '#{source}'"
+        end
 
-    ohai "Extracting nested container #{source.basename}"
-    container.new(@cask, source, @command).extract
-    FileUtils.remove_entry_secure(source)
+        ohai "Extracting nested container #{source.basename}"
+        container.new(@cask, source, @command).extract
+        FileUtils.remove_entry_secure(source)
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/pkg.rb b/Library/Homebrew/cask/lib/hbc/artifact/pkg.rb
index fb27308d7..e590a9082 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/pkg.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/pkg.rb
@@ -1,53 +1,57 @@
 require "hbc/artifact/base"
 
-class Hbc::Artifact::Pkg < Hbc::Artifact::Base
-  attr_reader :pkg_relative_path
+module Hbc
+  module Artifact
+    class Pkg < Base
+      attr_reader :pkg_relative_path
 
-  def self.artifact_dsl_key
-    :pkg
-  end
+      def self.artifact_dsl_key
+        :pkg
+      end
 
-  def load_pkg_description(pkg_description)
-    @pkg_relative_path = pkg_description.shift
-    @pkg_install_opts = pkg_description.shift
-    begin
-      if @pkg_install_opts.respond_to?(:keys)
-        @pkg_install_opts.assert_valid_keys(:allow_untrusted)
-      elsif @pkg_install_opts
-        raise
+      def load_pkg_description(pkg_description)
+        @pkg_relative_path = pkg_description.shift
+        @pkg_install_opts = pkg_description.shift
+        begin
+          if @pkg_install_opts.respond_to?(:keys)
+            @pkg_install_opts.assert_valid_keys(:allow_untrusted)
+          elsif @pkg_install_opts
+            raise
+          end
+          raise if pkg_description.nil?
+        rescue StandardError
+          raise CaskInvalidError.new(@cask, "Bad pkg stanza")
+        end
       end
-      raise if pkg_description.nil?
-    rescue StandardError
-      raise Hbc::CaskInvalidError.new(@cask, "Bad pkg stanza")
-    end
-  end
 
-  def pkg_install_opts(opt)
-    @pkg_install_opts[opt] if @pkg_install_opts.respond_to?(:keys)
-  end
+      def pkg_install_opts(opt)
+        @pkg_install_opts[opt] if @pkg_install_opts.respond_to?(:keys)
+      end
 
-  def install_phase
-    @cask.artifacts[:pkg].each { |pkg_description| run_installer(pkg_description) }
-  end
+      def install_phase
+        @cask.artifacts[:pkg].each { |pkg_description| run_installer(pkg_description) }
+      end
 
-  def uninstall_phase
-    # Do nothing. Must be handled explicitly by a separate :uninstall stanza.
-  end
+      def uninstall_phase
+        # Do nothing. Must be handled explicitly by a separate :uninstall stanza.
+      end
 
-  def run_installer(pkg_description)
-    load_pkg_description pkg_description
-    ohai "Running installer for #{@cask}; your password may be necessary."
-    ohai "Package installers may write to any location; options such as --appdir are ignored."
-    source = @cask.staged_path.join(pkg_relative_path)
-    unless source.exist?
-      raise Hbc::CaskError, "pkg source file not found: '#{source}'"
+      def run_installer(pkg_description)
+        load_pkg_description pkg_description
+        ohai "Running installer for #{@cask}; your password may be necessary."
+        ohai "Package installers may write to any location; options such as --appdir are ignored."
+        source = @cask.staged_path.join(pkg_relative_path)
+        unless source.exist?
+          raise CaskError, "pkg source file not found: '#{source}'"
+        end
+        args = [
+                 "-pkg",    source,
+                 "-target", "/"
+               ]
+        args << "-verboseR" if Hbc.verbose
+        args << "-allowUntrusted" if pkg_install_opts :allow_untrusted
+        @command.run!("/usr/sbin/installer", sudo: true, args: args, print_stdout: true)
+      end
     end
-    args = [
-             "-pkg",    source,
-             "-target", "/"
-           ]
-    args << "-verboseR" if Hbc.verbose
-    args << "-allowUntrusted" if pkg_install_opts :allow_untrusted
-    @command.run!("/usr/sbin/installer", sudo: true, args: args, print_stdout: true)
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/postflight_block.rb b/Library/Homebrew/cask/lib/hbc/artifact/postflight_block.rb
index 92b21a83f..bfe218f95 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/postflight_block.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/postflight_block.rb
@@ -1,4 +1,8 @@
 require "hbc/artifact/abstract_flight_block"
 
-class Hbc::Artifact::PostflightBlock < Hbc::Artifact::AbstractFlightBlock
+module Hbc
+  module Artifact
+    class PostflightBlock < AbstractFlightBlock
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/preflight_block.rb b/Library/Homebrew/cask/lib/hbc/artifact/preflight_block.rb
index 772a88016..35142df47 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/preflight_block.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/preflight_block.rb
@@ -1,4 +1,8 @@
 require "hbc/artifact/abstract_flight_block"
 
-class Hbc::Artifact::PreflightBlock < Hbc::Artifact::AbstractFlightBlock
+module Hbc
+  module Artifact
+    class PreflightBlock < AbstractFlightBlock
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/prefpane.rb b/Library/Homebrew/cask/lib/hbc/artifact/prefpane.rb
index e45cc0b19..a44f8ae3a 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/prefpane.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/prefpane.rb
@@ -1,7 +1,11 @@
 require "hbc/artifact/moved"
 
-class Hbc::Artifact::Prefpane < Hbc::Artifact::Moved
-  def self.artifact_english_name
-    "Preference Pane"
+module Hbc
+  module Artifact
+    class Prefpane < Moved
+      def self.artifact_english_name
+        "Preference Pane"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/qlplugin.rb b/Library/Homebrew/cask/lib/hbc/artifact/qlplugin.rb
index 6702aa5ef..ee41de2fe 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/qlplugin.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/qlplugin.rb
@@ -1,21 +1,25 @@
 require "hbc/artifact/moved"
 
-class Hbc::Artifact::Qlplugin < Hbc::Artifact::Moved
-  def self.artifact_english_name
-    "QuickLook Plugin"
-  end
+module Hbc
+  module Artifact
+    class Qlplugin < Moved
+      def self.artifact_english_name
+        "QuickLook Plugin"
+      end
 
-  def install_phase
-    super
-    reload_quicklook
-  end
+      def install_phase
+        super
+        reload_quicklook
+      end
 
-  def uninstall_phase
-    super
-    reload_quicklook
-  end
+      def uninstall_phase
+        super
+        reload_quicklook
+      end
 
-  def reload_quicklook
-    @command.run!("/usr/bin/qlmanage", args: ["-r"])
+      def reload_quicklook
+        @command.run!("/usr/bin/qlmanage", args: ["-r"])
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/relocated.rb b/Library/Homebrew/cask/lib/hbc/artifact/relocated.rb
index cd0054188..953045b32 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/relocated.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/relocated.rb
@@ -1,53 +1,57 @@
 require "hbc/artifact/base"
 
-class Hbc::Artifact::Relocated < Hbc::Artifact::Base
-  def summary
-    {
-      english_description: self.class.english_description,
-      contents:            @cask.artifacts[self.class.artifact_dsl_key].map(&method(:summarize_artifact)).compact,
-    }
-  end
-
-  attr_reader :source, :target
-
-  def printable_target
-    target.to_s.sub(%r{^#{ENV['HOME']}(#{File::SEPARATOR}|$)}, "~/")
-  end
-
-  ALT_NAME_ATTRIBUTE = "com.apple.metadata:kMDItemAlternateNames".freeze
-
-  # Try to make the asset searchable under the target name.  Spotlight
-  # respects this attribute for many filetypes, but ignores it for App
-  # bundles. Alfred 2.2 respects it even for App bundles.
-  def add_altname_metadata(file, altname)
-    return if altname.casecmp(file.basename).zero?
-    odebug "Adding #{ALT_NAME_ATTRIBUTE} metadata"
-    altnames = @command.run("/usr/bin/xattr",
-                            args:         ["-p", ALT_NAME_ATTRIBUTE, file.to_s],
-                            print_stderr: false).stdout.sub(%r{\A\((.*)\)\Z}, '\1')
-    odebug "Existing metadata is: '#{altnames}'"
-    altnames.concat(", ") unless altnames.empty?
-    altnames.concat(%Q{"#{altname}"})
-    altnames = "(#{altnames})"
-
-    # Some packges are shipped as u=rx (e.g. Bitcoin Core)
-    @command.run!("/bin/chmod", args: ["--", "u=rwx", file.to_s, file.realpath.to_s])
-
-    @command.run!("/usr/bin/xattr",
-                  args:         ["-w", ALT_NAME_ATTRIBUTE, altnames, file.to_s],
-                  print_stderr: false)
-  end
-
-  def load_specification(artifact_spec)
-    source_string, target_hash = artifact_spec
-    raise Hbc::CaskInvalidError if source_string.nil?
-    @source = @cask.staged_path.join(source_string)
-    if target_hash
-      raise Hbc::CaskInvalidError unless target_hash.respond_to?(:keys)
-      target_hash.assert_valid_keys(:target)
-      @target = Hbc.send(self.class.artifact_dirmethod).join(target_hash[:target])
-    else
-      @target = Hbc.send(self.class.artifact_dirmethod).join(source.basename)
+module Hbc
+  module Artifact
+    class Relocated < Base
+      def summary
+        {
+          english_description: self.class.english_description,
+          contents:            @cask.artifacts[self.class.artifact_dsl_key].map(&method(:summarize_artifact)).compact,
+        }
+      end
+
+      attr_reader :source, :target
+
+      def printable_target
+        target.to_s.sub(%r{^#{ENV['HOME']}(#{File::SEPARATOR}|$)}, "~/")
+      end
+
+      ALT_NAME_ATTRIBUTE = "com.apple.metadata:kMDItemAlternateNames".freeze
+
+      # Try to make the asset searchable under the target name.  Spotlight
+      # respects this attribute for many filetypes, but ignores it for App
+      # bundles. Alfred 2.2 respects it even for App bundles.
+      def add_altname_metadata(file, altname)
+        return if altname.casecmp(file.basename).zero?
+        odebug "Adding #{ALT_NAME_ATTRIBUTE} metadata"
+        altnames = @command.run("/usr/bin/xattr",
+                                args:         ["-p", ALT_NAME_ATTRIBUTE, file.to_s],
+                                print_stderr: false).stdout.sub(%r{\A\((.*)\)\Z}, '\1')
+        odebug "Existing metadata is: '#{altnames}'"
+        altnames.concat(", ") unless altnames.empty?
+        altnames.concat(%Q{"#{altname}"})
+        altnames = "(#{altnames})"
+
+        # Some packges are shipped as u=rx (e.g. Bitcoin Core)
+        @command.run!("/bin/chmod", args: ["--", "u=rwx", file.to_s, file.realpath.to_s])
+
+        @command.run!("/usr/bin/xattr",
+                      args:         ["-w", ALT_NAME_ATTRIBUTE, altnames, file.to_s],
+                      print_stderr: false)
+      end
+
+      def load_specification(artifact_spec)
+        source_string, target_hash = artifact_spec
+        raise CaskInvalidError if source_string.nil?
+        @source = @cask.staged_path.join(source_string)
+        if target_hash
+          raise CaskInvalidError unless target_hash.respond_to?(:keys)
+          target_hash.assert_valid_keys(:target)
+          @target = Hbc.send(self.class.artifact_dirmethod).join(target_hash[:target])
+        else
+          @target = Hbc.send(self.class.artifact_dirmethod).join(source.basename)
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/screen_saver.rb b/Library/Homebrew/cask/lib/hbc/artifact/screen_saver.rb
index bbd929152..4cdc6037c 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/screen_saver.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/screen_saver.rb
@@ -1,4 +1,8 @@
 require "hbc/artifact/moved"
 
-class Hbc::Artifact::ScreenSaver < Hbc::Artifact::Moved
+module Hbc
+  module Artifact
+    class ScreenSaver < Moved
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/service.rb b/Library/Homebrew/cask/lib/hbc/artifact/service.rb
index d5a00e4fe..1af93c533 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/service.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/service.rb
@@ -1,4 +1,8 @@
 require "hbc/artifact/moved"
 
-class Hbc::Artifact::Service < Hbc::Artifact::Moved
+module Hbc
+  module Artifact
+    class Service < Moved
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/stage_only.rb b/Library/Homebrew/cask/lib/hbc/artifact/stage_only.rb
index 7a48b19aa..594c5bef9 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/stage_only.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/stage_only.rb
@@ -1,15 +1,19 @@
 require "hbc/artifact/base"
 
-class Hbc::Artifact::StageOnly < Hbc::Artifact::Base
-  def self.artifact_dsl_key
-    :stage_only
-  end
+module Hbc
+  module Artifact
+    class StageOnly < Base
+      def self.artifact_dsl_key
+        :stage_only
+      end
 
-  def install_phase
-    # do nothing
-  end
+      def install_phase
+        # do nothing
+      end
 
-  def uninstall_phase
-    # do nothing
+      def uninstall_phase
+        # do nothing
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/suite.rb b/Library/Homebrew/cask/lib/hbc/artifact/suite.rb
index cdfb757dd..35251f70c 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/suite.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/suite.rb
@@ -1,11 +1,15 @@
 require "hbc/artifact/moved"
 
-class Hbc::Artifact::Suite < Hbc::Artifact::Moved
-  def self.artifact_english_name
-    "App Suite"
-  end
+module Hbc
+  module Artifact
+    class Suite < Moved
+      def self.artifact_english_name
+        "App Suite"
+      end
 
-  def self.artifact_dirmethod
-    :appdir
+      def self.artifact_dirmethod
+        :appdir
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/symlinked.rb b/Library/Homebrew/cask/lib/hbc/artifact/symlinked.rb
index 7432df577..3ab45cccc 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/symlinked.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/symlinked.rb
@@ -1,65 +1,69 @@
 require "hbc/artifact/relocated"
 
-class Hbc::Artifact::Symlinked < Hbc::Artifact::Relocated
-  def self.link_type_english_name
-    "Symlink"
-  end
+module Hbc
+  module Artifact
+    class Symlinked < Relocated
+      def self.link_type_english_name
+        "Symlink"
+      end
 
-  def self.english_description
-    "#{artifact_english_name} #{link_type_english_name}s"
-  end
+      def self.english_description
+        "#{artifact_english_name} #{link_type_english_name}s"
+      end
 
-  def self.islink?(path)
-    path.symlink?
-  end
+      def self.islink?(path)
+        path.symlink?
+      end
 
-  def link(artifact_spec)
-    load_specification artifact_spec
-    return unless preflight_checks(source, target)
-    ohai "#{self.class.link_type_english_name}ing #{self.class.artifact_english_name} '#{source.basename}' to '#{target}'"
-    create_filesystem_link(source, target)
-  end
+      def link(artifact_spec)
+        load_specification artifact_spec
+        return unless preflight_checks(source, target)
+        ohai "#{self.class.link_type_english_name}ing #{self.class.artifact_english_name} '#{source.basename}' to '#{target}'"
+        create_filesystem_link(source, target)
+      end
 
-  def unlink(artifact_spec)
-    load_specification artifact_spec
-    return unless self.class.islink?(target)
-    ohai "Removing #{self.class.artifact_english_name} #{self.class.link_type_english_name.downcase}: '#{target}'"
-    target.delete
-  end
+      def unlink(artifact_spec)
+        load_specification artifact_spec
+        return unless self.class.islink?(target)
+        ohai "Removing #{self.class.artifact_english_name} #{self.class.link_type_english_name.downcase}: '#{target}'"
+        target.delete
+      end
 
-  def install_phase
-    @cask.artifacts[self.class.artifact_dsl_key].each(&method(:link))
-  end
+      def install_phase
+        @cask.artifacts[self.class.artifact_dsl_key].each(&method(:link))
+      end
 
-  def uninstall_phase
-    @cask.artifacts[self.class.artifact_dsl_key].each(&method(:unlink))
-  end
+      def uninstall_phase
+        @cask.artifacts[self.class.artifact_dsl_key].each(&method(:unlink))
+      end
 
-  def preflight_checks(source, target)
-    if target.exist? && !self.class.islink?(target)
-      ohai "It seems there is already #{self.class.artifact_english_article} #{self.class.artifact_english_name} at '#{target}'; not linking."
-      return false
-    end
-    unless source.exist?
-      raise Hbc::CaskError, "It seems the #{self.class.link_type_english_name.downcase} source is not there: '#{source}'"
-    end
-    true
-  end
+      def preflight_checks(source, target)
+        if target.exist? && !self.class.islink?(target)
+          ohai "It seems there is already #{self.class.artifact_english_article} #{self.class.artifact_english_name} at '#{target}'; not linking."
+          return false
+        end
+        unless source.exist?
+          raise CaskError, "It seems the #{self.class.link_type_english_name.downcase} source is not there: '#{source}'"
+        end
+        true
+      end
 
-  def create_filesystem_link(source, target)
-    Pathname.new(target).dirname.mkpath
-    @command.run!("/bin/ln", args: ["-hfs", "--", source, target])
-    add_altname_metadata source, target.basename.to_s
-  end
+      def create_filesystem_link(source, target)
+        Pathname.new(target).dirname.mkpath
+        @command.run!("/bin/ln", args: ["-hfs", "--", source, target])
+        add_altname_metadata source, target.basename.to_s
+      end
 
-  def summarize_artifact(artifact_spec)
-    load_specification artifact_spec
+      def summarize_artifact(artifact_spec)
+        load_specification artifact_spec
 
-    return unless self.class.islink?(target)
+        return unless self.class.islink?(target)
 
-    link_description = "#{Tty.red}Broken Link#{Tty.reset}: " unless target.exist?
-    target_readlink_abv = " (#{target.readlink.abv})" if target.readlink.exist?
+        link_description = "#{Tty.red}Broken Link#{Tty.reset}: " unless target.exist?
+        target_readlink_abv = " (#{target.readlink.abv})" if target.readlink.exist?
 
-    "#{link_description}#{printable_target} -> #{target.readlink}#{target_readlink_abv}"
+        "#{link_description}#{printable_target} -> #{target.readlink}#{target_readlink_abv}"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/uninstall.rb b/Library/Homebrew/cask/lib/hbc/artifact/uninstall.rb
index 12010aeb8..8b5603064 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/uninstall.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/uninstall.rb
@@ -1,4 +1,8 @@
 require "hbc/artifact/uninstall_base"
 
-class Hbc::Artifact::Uninstall < Hbc::Artifact::UninstallBase
+module Hbc
+  module Artifact
+    class Uninstall < UninstallBase
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/uninstall_base.rb b/Library/Homebrew/cask/lib/hbc/artifact/uninstall_base.rb
index f92e09a89..63ffd18c9 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/uninstall_base.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/uninstall_base.rb
@@ -2,248 +2,252 @@ require "pathname"
 
 require "hbc/artifact/base"
 
-class Hbc::Artifact::UninstallBase < Hbc::Artifact::Base
-  # TODO: 500 is also hardcoded in cask/pkg.rb, but much of
-  #       that logic is probably in the wrong location
-
-  PATH_ARG_SLICE_SIZE = 500
-
-  ORDERED_DIRECTIVES = [
-                         :early_script,
-                         :launchctl,
-                         :quit,
-                         :signal,
-                         :login_item,
-                         :kext,
-                         :script,
-                         :pkgutil,
-                         :delete,
-                         :trash,
-                         :rmdir,
-                       ].freeze
-
-  # TODO: these methods were consolidated here from separate
-  #       sources and should be refactored for consistency
-
-  def self.expand_path_strings(path_strings)
-    path_strings.map { |path_string|
-      path_string.start_with?("~") ? Pathname.new(path_string).expand_path : Pathname.new(path_string)
-    }
-  end
+module Hbc
+  module Artifact
+    class UninstallBase < Base
+      # TODO: 500 is also hardcoded in cask/pkg.rb, but much of
+      #       that logic is probably in the wrong location
+
+      PATH_ARG_SLICE_SIZE = 500
+
+      ORDERED_DIRECTIVES = [
+                             :early_script,
+                             :launchctl,
+                             :quit,
+                             :signal,
+                             :login_item,
+                             :kext,
+                             :script,
+                             :pkgutil,
+                             :delete,
+                             :trash,
+                             :rmdir,
+                           ].freeze
+
+      # TODO: these methods were consolidated here from separate
+      #       sources and should be refactored for consistency
+
+      def self.expand_path_strings(path_strings)
+        path_strings.map { |path_string|
+          path_string.start_with?("~") ? Pathname.new(path_string).expand_path : Pathname.new(path_string)
+        }
+      end
 
-  def self.remove_relative_path_strings(action, path_strings)
-    relative = path_strings.map { |path_string|
-      path_string if %r{/\.\.(?:/|\Z)}.match(path_string) || !%r{\A/}.match(path_string)
-    }.compact
-    relative.each do |path_string|
-      opoo "Skipping #{action} for relative path #{path_string}"
-    end
-    path_strings - relative
-  end
+      def self.remove_relative_path_strings(action, path_strings)
+        relative = path_strings.map { |path_string|
+          path_string if %r{/\.\.(?:/|\Z)}.match(path_string) || !%r{\A/}.match(path_string)
+        }.compact
+        relative.each do |path_string|
+          opoo "Skipping #{action} for relative path #{path_string}"
+        end
+        path_strings - relative
+      end
 
-  def self.remove_undeletable_path_strings(action, path_strings)
-    undeletable = path_strings.map { |path_string|
-      path_string if MacOS.undeletable?(Pathname.new(path_string))
-    }.compact
-    undeletable.each do |path_string|
-      opoo "Skipping #{action} for undeletable path #{path_string}"
-    end
-    path_strings - undeletable
-  end
+      def self.remove_undeletable_path_strings(action, path_strings)
+        undeletable = path_strings.map { |path_string|
+          path_string if MacOS.undeletable?(Pathname.new(path_string))
+        }.compact
+        undeletable.each do |path_string|
+          opoo "Skipping #{action} for undeletable path #{path_string}"
+        end
+        path_strings - undeletable
+      end
 
-  def install_phase
-    odebug "Nothing to do. The uninstall artifact has no install phase."
-  end
+      def install_phase
+        odebug "Nothing to do. The uninstall artifact has no install phase."
+      end
 
-  def uninstall_phase
-    dispatch_uninstall_directives
-  end
+      def uninstall_phase
+        dispatch_uninstall_directives
+      end
 
-  def dispatch_uninstall_directives(expand_tilde = true)
-    directives_set = @cask.artifacts[stanza]
-    ohai "Running #{stanza} process for #{@cask}; your password may be necessary"
+      def dispatch_uninstall_directives(expand_tilde = true)
+        directives_set = @cask.artifacts[stanza]
+        ohai "Running #{stanza} process for #{@cask}; your password may be necessary"
 
-    directives_set.each do |directives|
-      warn_for_unknown_directives(directives)
-    end
+        directives_set.each do |directives|
+          warn_for_unknown_directives(directives)
+        end
 
-    ORDERED_DIRECTIVES.each do |directive_sym|
-      directives_set.select { |h| h.key?(directive_sym) }.each do |directives|
-        args = [directives]
-        args << expand_tilde if [:delete, :trash, :rmdir].include?(directive_sym)
-        send("uninstall_#{directive_sym}", *args)
+        ORDERED_DIRECTIVES.each do |directive_sym|
+          directives_set.select { |h| h.key?(directive_sym) }.each do |directives|
+            args = [directives]
+            args << expand_tilde if [:delete, :trash, :rmdir].include?(directive_sym)
+            send("uninstall_#{directive_sym}", *args)
+          end
+        end
       end
-    end
-  end
 
-  private
+      private
 
-  def stanza
-    self.class.artifact_dsl_key
-  end
+      def stanza
+        self.class.artifact_dsl_key
+      end
 
-  def warn_for_unknown_directives(directives)
-    unknown_keys = directives.keys - ORDERED_DIRECTIVES
-    return if unknown_keys.empty?
-    opoo %Q{Unknown arguments to #{stanza} -- #{unknown_keys.inspect}. Running "brew update; brew cleanup; brew cask cleanup" will likely fix it.}
-  end
+      def warn_for_unknown_directives(directives)
+        unknown_keys = directives.keys - ORDERED_DIRECTIVES
+        return if unknown_keys.empty?
+        opoo %Q{Unknown arguments to #{stanza} -- #{unknown_keys.inspect}. Running "brew update; brew cleanup; brew cask cleanup" will likely fix it.}
+      end
 
-  # Preserve prior functionality of script which runs first. Should rarely be needed.
-  # :early_script should not delete files, better defer that to :script.
-  # If Cask writers never need :early_script it may be removed in the future.
-  def uninstall_early_script(directives)
-    uninstall_script(directives, directive_name: :early_script)
-  end
+      # Preserve prior functionality of script which runs first. Should rarely be needed.
+      # :early_script should not delete files, better defer that to :script.
+      # If Cask writers never need :early_script it may be removed in the future.
+      def uninstall_early_script(directives)
+        uninstall_script(directives, directive_name: :early_script)
+      end
 
-  # :launchctl must come before :quit/:signal for cases where app would instantly re-launch
-  def uninstall_launchctl(directives)
-    Array(directives[:launchctl]).each do |service|
-      ohai "Removing launchctl service #{service}"
-      [false, true].each do |with_sudo|
-        plist_status = @command.run("/bin/launchctl", args: ["list", service], sudo: with_sudo, print_stderr: false).stdout
-        if plist_status =~ %r{^\{}
-          @command.run!("/bin/launchctl", args: ["remove", service], sudo: with_sudo)
-          sleep 1
+      # :launchctl must come before :quit/:signal for cases where app would instantly re-launch
+      def uninstall_launchctl(directives)
+        Array(directives[:launchctl]).each do |service|
+          ohai "Removing launchctl service #{service}"
+          [false, true].each do |with_sudo|
+            plist_status = @command.run("/bin/launchctl", args: ["list", service], sudo: with_sudo, print_stderr: false).stdout
+            if plist_status =~ %r{^\{}
+              @command.run!("/bin/launchctl", args: ["remove", service], sudo: with_sudo)
+              sleep 1
+            end
+            paths = ["/Library/LaunchAgents/#{service}.plist",
+                     "/Library/LaunchDaemons/#{service}.plist"]
+            paths.each { |elt| elt.prepend(ENV["HOME"]) } unless with_sudo
+            paths = paths.map { |elt| Pathname(elt) }.select(&:exist?)
+            paths.each do |path|
+              @command.run!("/bin/rm", args: ["-f", "--", path], sudo: with_sudo)
+            end
+            # undocumented and untested: pass a path to uninstall :launchctl
+            next unless Pathname(service).exist?
+            @command.run!("/bin/launchctl", args: ["unload", "-w", "--", service], sudo: with_sudo)
+            @command.run!("/bin/rm",        args: ["-f", "--", service], sudo: with_sudo)
+            sleep 1
+          end
         end
-        paths = ["/Library/LaunchAgents/#{service}.plist",
-                 "/Library/LaunchDaemons/#{service}.plist"]
-        paths.each { |elt| elt.prepend(ENV["HOME"]) } unless with_sudo
-        paths = paths.map { |elt| Pathname(elt) }.select(&:exist?)
-        paths.each do |path|
-          @command.run!("/bin/rm", args: ["-f", "--", path], sudo: with_sudo)
+      end
+
+      # :quit/:signal must come before :kext so the kext will not be in use by a running process
+      def uninstall_quit(directives)
+        Array(directives[:quit]).each do |id|
+          ohai "Quitting application ID #{id}"
+          num_running = count_running_processes(id)
+          next unless num_running > 0
+          @command.run!("/usr/bin/osascript", args: ["-e", %Q{tell application id "#{id}" to quit}], sudo: true)
+          sleep 3
         end
-        # undocumented and untested: pass a path to uninstall :launchctl
-        next unless Pathname(service).exist?
-        @command.run!("/bin/launchctl", args: ["unload", "-w", "--", service], sudo: with_sudo)
-        @command.run!("/bin/rm",        args: ["-f", "--", service], sudo: with_sudo)
-        sleep 1
       end
-    end
-  end
 
-  # :quit/:signal must come before :kext so the kext will not be in use by a running process
-  def uninstall_quit(directives)
-    Array(directives[:quit]).each do |id|
-      ohai "Quitting application ID #{id}"
-      num_running = count_running_processes(id)
-      next unless num_running > 0
-      @command.run!("/usr/bin/osascript", args: ["-e", %Q{tell application id "#{id}" to quit}], sudo: true)
-      sleep 3
-    end
-  end
+      # :signal should come after :quit so it can be used as a backup when :quit fails
+      def uninstall_signal(directives)
+        Array(directives[:signal]).flatten.each_slice(2) do |pair|
+          raise CaskInvalidError.new(@cask, "Each #{stanza} :signal must have 2 elements.") unless pair.length == 2
+          signal, id = pair
+          ohai "Signalling '#{signal}' to application ID '#{id}'"
+          pids = get_unix_pids(id)
+          next unless pids.any?
+          # Note that unlike :quit, signals are sent from the current user (not
+          # upgraded to the superuser).  This is a todo item for the future, but
+          # there should be some additional thought/safety checks about that, as a
+          # misapplied "kill" by root could bring down the system. The fact that we
+          # learned the pid from AppleScript is already some degree of protection,
+          # though indirect.
+          odebug "Unix ids are #{pids.inspect} for processes with bundle identifier #{id}"
+          Process.kill(signal, *pids)
+          sleep 3
+        end
+      end
 
-  # :signal should come after :quit so it can be used as a backup when :quit fails
-  def uninstall_signal(directives)
-    Array(directives[:signal]).flatten.each_slice(2) do |pair|
-      raise Hbc::CaskInvalidError.new(@cask, "Each #{stanza} :signal must have 2 elements.") unless pair.length == 2
-      signal, id = pair
-      ohai "Signalling '#{signal}' to application ID '#{id}'"
-      pids = get_unix_pids(id)
-      next unless pids.any?
-      # Note that unlike :quit, signals are sent from the current user (not
-      # upgraded to the superuser).  This is a todo item for the future, but
-      # there should be some additional thought/safety checks about that, as a
-      # misapplied "kill" by root could bring down the system. The fact that we
-      # learned the pid from AppleScript is already some degree of protection,
-      # though indirect.
-      odebug "Unix ids are #{pids.inspect} for processes with bundle identifier #{id}"
-      Process.kill(signal, *pids)
-      sleep 3
-    end
-  end
+      def count_running_processes(bundle_id)
+        @command.run!("/usr/bin/osascript",
+                      args: ["-e", %Q{tell application "System Events" to count processes whose bundle identifier is "#{bundle_id}"}],
+                      sudo: true).stdout.to_i
+      end
 
-  def count_running_processes(bundle_id)
-    @command.run!("/usr/bin/osascript",
-                  args: ["-e", %Q{tell application "System Events" to count processes whose bundle identifier is "#{bundle_id}"}],
-                  sudo: true).stdout.to_i
-  end
+      def get_unix_pids(bundle_id)
+        pid_string = @command.run!("/usr/bin/osascript",
+                                   args: ["-e", %Q{tell application "System Events" to get the unix id of every process whose bundle identifier is "#{bundle_id}"}],
+                                   sudo: true).stdout.chomp
+        return [] unless pid_string =~ %r{\A\d+(?:\s*,\s*\d+)*\Z} # sanity check
+        pid_string.split(%r{\s*,\s*}).map(&:strip).map(&:to_i)
+      end
 
-  def get_unix_pids(bundle_id)
-    pid_string = @command.run!("/usr/bin/osascript",
-                               args: ["-e", %Q{tell application "System Events" to get the unix id of every process whose bundle identifier is "#{bundle_id}"}],
-                               sudo: true).stdout.chomp
-    return [] unless pid_string =~ %r{\A\d+(?:\s*,\s*\d+)*\Z} # sanity check
-    pid_string.split(%r{\s*,\s*}).map(&:strip).map(&:to_i)
-  end
+      def uninstall_login_item(directives)
+        Array(directives[:login_item]).each do |name|
+          ohai "Removing login item #{name}"
+          @command.run!("/usr/bin/osascript",
+                        args: ["-e", %Q{tell application "System Events" to delete every login item whose name is "#{name}"}],
+                        sudo: false)
+          sleep 1
+        end
+      end
 
-  def uninstall_login_item(directives)
-    Array(directives[:login_item]).each do |name|
-      ohai "Removing login item #{name}"
-      @command.run!("/usr/bin/osascript",
-                    args: ["-e", %Q{tell application "System Events" to delete every login item whose name is "#{name}"}],
-                    sudo: false)
-      sleep 1
-    end
-  end
+      # :kext should be unloaded before attempting to delete the relevant file
+      def uninstall_kext(directives)
+        Array(directives[:kext]).each do |kext|
+          ohai "Unloading kernel extension #{kext}"
+          is_loaded = @command.run!("/usr/sbin/kextstat", args: ["-l", "-b", kext], sudo: true).stdout
+          if is_loaded.length > 1
+            @command.run!("/sbin/kextunload", args: ["-b", kext], sudo: true)
+            sleep 1
+          end
+        end
+      end
 
-  # :kext should be unloaded before attempting to delete the relevant file
-  def uninstall_kext(directives)
-    Array(directives[:kext]).each do |kext|
-      ohai "Unloading kernel extension #{kext}"
-      is_loaded = @command.run!("/usr/sbin/kextstat", args: ["-l", "-b", kext], sudo: true).stdout
-      if is_loaded.length > 1
-        @command.run!("/sbin/kextunload", args: ["-b", kext], sudo: true)
+      # :script must come before :pkgutil, :delete, or :trash so that the script file is not already deleted
+      def uninstall_script(directives, directive_name: :script)
+        executable, script_arguments = self.class.read_script_arguments(directives,
+                                                                        "uninstall",
+                                                                        { must_succeed: true, sudo: true },
+                                                                        { print_stdout: true },
+                                                                        directive_name)
+        ohai "Running uninstall script #{executable}"
+        raise CaskInvalidError.new(@cask, "#{stanza} :#{directive_name} without :executable.") if executable.nil?
+        executable_path = @cask.staged_path.join(executable)
+        @command.run("/bin/chmod", args: ["--", "+x", executable_path]) if File.exist?(executable_path)
+        @command.run(executable_path, script_arguments)
         sleep 1
       end
-    end
-  end
-
-  # :script must come before :pkgutil, :delete, or :trash so that the script file is not already deleted
-  def uninstall_script(directives, directive_name: :script)
-    executable, script_arguments = self.class.read_script_arguments(directives,
-                                                                    "uninstall",
-                                                                    { must_succeed: true, sudo: true },
-                                                                    { print_stdout: true },
-                                                                    directive_name)
-    ohai "Running uninstall script #{executable}"
-    raise Hbc::CaskInvalidError.new(@cask, "#{stanza} :#{directive_name} without :executable.") if executable.nil?
-    executable_path = @cask.staged_path.join(executable)
-    @command.run("/bin/chmod", args: ["--", "+x", executable_path]) if File.exist?(executable_path)
-    @command.run(executable_path, script_arguments)
-    sleep 1
-  end
 
-  def uninstall_pkgutil(directives)
-    ohai "Removing files from pkgutil Bill-of-Materials"
-    Array(directives[:pkgutil]).each do |regexp|
-      pkgs = Hbc::Pkg.all_matching(regexp, @command)
-      pkgs.each(&:uninstall)
-    end
-  end
+      def uninstall_pkgutil(directives)
+        ohai "Removing files from pkgutil Bill-of-Materials"
+        Array(directives[:pkgutil]).each do |regexp|
+          pkgs = Hbc::Pkg.all_matching(regexp, @command)
+          pkgs.each(&:uninstall)
+        end
+      end
 
-  def uninstall_delete(directives, expand_tilde = true)
-    Array(directives[:delete]).concat(Array(directives[:trash])).flatten.each_slice(PATH_ARG_SLICE_SIZE) do |path_slice|
-      ohai "Removing files: #{path_slice.utf8_inspect}"
-      path_slice = self.class.expand_path_strings(path_slice) if expand_tilde
-      path_slice = self.class.remove_relative_path_strings(:delete, path_slice)
-      path_slice = self.class.remove_undeletable_path_strings(:delete, path_slice)
-      @command.run!("/bin/rm", args: path_slice.unshift("-rf", "--"), sudo: true)
-    end
-  end
+      def uninstall_delete(directives, expand_tilde = true)
+        Array(directives[:delete]).concat(Array(directives[:trash])).flatten.each_slice(PATH_ARG_SLICE_SIZE) do |path_slice|
+          ohai "Removing files: #{path_slice.utf8_inspect}"
+          path_slice = self.class.expand_path_strings(path_slice) if expand_tilde
+          path_slice = self.class.remove_relative_path_strings(:delete, path_slice)
+          path_slice = self.class.remove_undeletable_path_strings(:delete, path_slice)
+          @command.run!("/bin/rm", args: path_slice.unshift("-rf", "--"), sudo: true)
+        end
+      end
 
-  # :trash functionality is stubbed as a synonym for :delete
-  # TODO: make :trash work differently, moving files to the Trash
-  def uninstall_trash(directives, expand_tilde = true)
-    uninstall_delete(directives, expand_tilde)
-  end
+      # :trash functionality is stubbed as a synonym for :delete
+      # TODO: make :trash work differently, moving files to the Trash
+      def uninstall_trash(directives, expand_tilde = true)
+        uninstall_delete(directives, expand_tilde)
+      end
 
-  def uninstall_rmdir(directives, expand_tilde = true)
-    Array(directives[:rmdir]).flatten.each do |directory|
-      directory = self.class.expand_path_strings([directory]).first if expand_tilde
-      directory = self.class.remove_relative_path_strings(:rmdir, [directory]).first
-      directory = self.class.remove_undeletable_path_strings(:rmdir, [directory]).first
-      next if directory.to_s.empty?
-      ohai "Removing directory if empty: #{directory.to_s.utf8_inspect}"
-      directory = Pathname.new(directory)
-      next unless directory.exist?
-      @command.run!("/bin/rm",
-                    args:         ["-f", "--", directory.join(".DS_Store")],
-                    sudo:         true,
-                    print_stderr: false)
-      @command.run("/bin/rmdir",
-                   args:         ["--", directory],
-                   sudo:         true,
-                   print_stderr: false)
+      def uninstall_rmdir(directives, expand_tilde = true)
+        Array(directives[:rmdir]).flatten.each do |directory|
+          directory = self.class.expand_path_strings([directory]).first if expand_tilde
+          directory = self.class.remove_relative_path_strings(:rmdir, [directory]).first
+          directory = self.class.remove_undeletable_path_strings(:rmdir, [directory]).first
+          next if directory.to_s.empty?
+          ohai "Removing directory if empty: #{directory.to_s.utf8_inspect}"
+          directory = Pathname.new(directory)
+          next unless directory.exist?
+          @command.run!("/bin/rm",
+                        args:         ["-f", "--", directory.join(".DS_Store")],
+                        sudo:         true,
+                        print_stderr: false)
+          @command.run("/bin/rmdir",
+                       args:         ["--", directory],
+                       sudo:         true,
+                       print_stderr: false)
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/vst3_plugin.rb b/Library/Homebrew/cask/lib/hbc/artifact/vst3_plugin.rb
index 243884435..056fffc2a 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/vst3_plugin.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/vst3_plugin.rb
@@ -1,4 +1,8 @@
 require "hbc/artifact/moved"
 
-class Hbc::Artifact::Vst3Plugin < Hbc::Artifact::Moved
+module Hbc
+  module Artifact
+    class Vst3Plugin < Moved
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/vst_plugin.rb b/Library/Homebrew/cask/lib/hbc/artifact/vst_plugin.rb
index 8d0546480..f38804635 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/vst_plugin.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/vst_plugin.rb
@@ -1,4 +1,8 @@
 require "hbc/artifact/moved"
 
-class Hbc::Artifact::VstPlugin < Hbc::Artifact::Moved
+module Hbc
+  module Artifact
+    class VstPlugin < Moved
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/artifact/zap.rb b/Library/Homebrew/cask/lib/hbc/artifact/zap.rb
index 8bd8da63b..503ea35c4 100644
--- a/Library/Homebrew/cask/lib/hbc/artifact/zap.rb
+++ b/Library/Homebrew/cask/lib/hbc/artifact/zap.rb
@@ -1,16 +1,20 @@
 require "hbc/artifact/uninstall_base"
 
-class Hbc::Artifact::Zap < Hbc::Artifact::UninstallBase
-  def install_phase
-    odebug "Nothing to do. The zap artifact has no install phase."
-  end
+module Hbc
+  module Artifact
+    class Zap < UninstallBase
+      def install_phase
+        odebug "Nothing to do. The zap artifact has no install phase."
+      end
 
-  def uninstall_phase
-    odebug "Nothing to do. The zap artifact has no uninstall phase."
-  end
+      def uninstall_phase
+        odebug "Nothing to do. The zap artifact has no uninstall phase."
+      end
 
-  def zap_phase
-    expand_tilde = true
-    dispatch_uninstall_directives(expand_tilde)
+      def zap_phase
+        expand_tilde = true
+        dispatch_uninstall_directives(expand_tilde)
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/audit.rb b/Library/Homebrew/cask/lib/hbc/audit.rb
index 98f09ffa4..476f2aec0 100644
--- a/Library/Homebrew/cask/lib/hbc/audit.rb
+++ b/Library/Homebrew/cask/lib/hbc/audit.rb
@@ -2,215 +2,217 @@ require "hbc/checkable"
 require "hbc/download"
 require "digest"
 
-class Hbc::Audit
-  include Hbc::Checkable
+module Hbc
+  class Audit
+    include Checkable
 
-  attr_reader :cask, :download
+    attr_reader :cask, :download
 
-  def initialize(cask, download: false, check_token_conflicts: false, command: Hbc::SystemCommand)
-    @cask = cask
-    @download = download
-    @check_token_conflicts = check_token_conflicts
-    @command = command
-  end
+    def initialize(cask, download: false, check_token_conflicts: false, command: SystemCommand)
+      @cask = cask
+      @download = download
+      @check_token_conflicts = check_token_conflicts
+      @command = command
+    end
 
-  def check_token_conflicts?
-    @check_token_conflicts
-  end
+    def check_token_conflicts?
+      @check_token_conflicts
+    end
 
-  def run!
-    check_required_stanzas
-    check_version
-    check_sha256
-    check_appcast
-    check_url
-    check_generic_artifacts
-    check_token_conflicts
-    check_download
-    self
-  rescue StandardError => e
-    odebug "#{e.message}\n#{e.backtrace.join("\n")}"
-    add_error "exception while auditing #{cask}: #{e.message}"
-    self
-  end
+    def run!
+      check_required_stanzas
+      check_version
+      check_sha256
+      check_appcast
+      check_url
+      check_generic_artifacts
+      check_token_conflicts
+      check_download
+      self
+    rescue StandardError => e
+      odebug "#{e.message}\n#{e.backtrace.join("\n")}"
+      add_error "exception while auditing #{cask}: #{e.message}"
+      self
+    end
 
-  def success?
-    !(errors? || warnings?)
-  end
+    def success?
+      !(errors? || warnings?)
+    end
 
-  def summary_header
-    "audit for #{cask}"
-  end
+    def summary_header
+      "audit for #{cask}"
+    end
 
-  private
+    private
 
-  def check_required_stanzas
-    odebug "Auditing required stanzas"
-    %i{version sha256 url homepage}.each do |sym|
-      add_error "a #{sym} stanza is required" unless cask.send(sym)
+    def check_required_stanzas
+      odebug "Auditing required stanzas"
+      %i{version sha256 url homepage}.each do |sym|
+        add_error "a #{sym} stanza is required" unless cask.send(sym)
+      end
+      add_error "a license stanza is required (:unknown is OK)" unless cask.license
+      add_error "at least one name stanza is required" if cask.name.empty?
+      # TODO: specific DSL knowledge should not be spread around in various files like this
+      # TODO: nested_container should not still be a pseudo-artifact at this point
+      installable_artifacts = cask.artifacts.reject { |k| [:uninstall, :zap, :nested_container].include?(k) }
+      add_error "at least one activatable artifact stanza is required" if installable_artifacts.empty?
     end
-    add_error "a license stanza is required (:unknown is OK)" unless cask.license
-    add_error "at least one name stanza is required" if cask.name.empty?
-    # TODO: specific DSL knowledge should not be spread around in various files like this
-    # TODO: nested_container should not still be a pseudo-artifact at this point
-    installable_artifacts = cask.artifacts.reject { |k| [:uninstall, :zap, :nested_container].include?(k) }
-    add_error "at least one activatable artifact stanza is required" if installable_artifacts.empty?
-  end
 
-  def check_version
-    return unless cask.version
-    check_no_string_version_latest
-  end
+    def check_version
+      return unless cask.version
+      check_no_string_version_latest
+    end
 
-  def check_no_string_version_latest
-    odebug "Verifying version :latest does not appear as a string ('latest')"
-    return unless cask.version.raw_version == "latest"
-    add_error "you should use version :latest instead of version 'latest'"
-  end
+    def check_no_string_version_latest
+      odebug "Verifying version :latest does not appear as a string ('latest')"
+      return unless cask.version.raw_version == "latest"
+      add_error "you should use version :latest instead of version 'latest'"
+    end
 
-  def check_sha256
-    return unless cask.sha256
-    check_sha256_no_check_if_latest
-    check_sha256_actually_256
-    check_sha256_invalid
-  end
+    def check_sha256
+      return unless cask.sha256
+      check_sha256_no_check_if_latest
+      check_sha256_actually_256
+      check_sha256_invalid
+    end
 
-  def check_sha256_no_check_if_latest
-    odebug "Verifying sha256 :no_check with version :latest"
-    return unless cask.version.latest? && cask.sha256 != :no_check
-    add_error "you should use sha256 :no_check when version is :latest"
-  end
+    def check_sha256_no_check_if_latest
+      odebug "Verifying sha256 :no_check with version :latest"
+      return unless cask.version.latest? && cask.sha256 != :no_check
+      add_error "you should use sha256 :no_check when version is :latest"
+    end
 
-  def check_sha256_actually_256(sha256: cask.sha256, stanza: "sha256")
-    odebug "Verifying #{stanza} string is a legal SHA-256 digest"
-    return unless sha256.is_a?(String)
-    return if sha256.length == 64 && sha256[%r{^[0-9a-f]+$}i]
-    add_error "#{stanza} string must be of 64 hexadecimal characters"
-  end
+    def check_sha256_actually_256(sha256: cask.sha256, stanza: "sha256")
+      odebug "Verifying #{stanza} string is a legal SHA-256 digest"
+      return unless sha256.is_a?(String)
+      return if sha256.length == 64 && sha256[%r{^[0-9a-f]+$}i]
+      add_error "#{stanza} string must be of 64 hexadecimal characters"
+    end
 
-  def check_sha256_invalid(sha256: cask.sha256, stanza: "sha256")
-    odebug "Verifying #{stanza} is not a known invalid value"
-    empty_sha256 = "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
-    return unless sha256 == empty_sha256
-    add_error "cannot use the sha256 for an empty string in #{stanza}: #{empty_sha256}"
-  end
+    def check_sha256_invalid(sha256: cask.sha256, stanza: "sha256")
+      odebug "Verifying #{stanza} is not a known invalid value"
+      empty_sha256 = "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
+      return unless sha256 == empty_sha256
+      add_error "cannot use the sha256 for an empty string in #{stanza}: #{empty_sha256}"
+    end
 
-  def check_appcast
-    return unless cask.appcast
-    odebug "Auditing appcast"
-    check_appcast_has_checkpoint
-    return unless cask.appcast.checkpoint
-    check_sha256_actually_256(sha256: cask.appcast.checkpoint, stanza: "appcast :checkpoint")
-    check_sha256_invalid(sha256: cask.appcast.checkpoint, stanza: "appcast :checkpoint")
-    return unless download
-    check_appcast_http_code
-    check_appcast_checkpoint_accuracy
-  end
+    def check_appcast
+      return unless cask.appcast
+      odebug "Auditing appcast"
+      check_appcast_has_checkpoint
+      return unless cask.appcast.checkpoint
+      check_sha256_actually_256(sha256: cask.appcast.checkpoint, stanza: "appcast :checkpoint")
+      check_sha256_invalid(sha256: cask.appcast.checkpoint, stanza: "appcast :checkpoint")
+      return unless download
+      check_appcast_http_code
+      check_appcast_checkpoint_accuracy
+    end
 
-  def check_appcast_has_checkpoint
-    odebug "Verifying appcast has :checkpoint key"
-    add_error "a checkpoint sha256 is required for appcast" unless cask.appcast.checkpoint
-  end
+    def check_appcast_has_checkpoint
+      odebug "Verifying appcast has :checkpoint key"
+      add_error "a checkpoint sha256 is required for appcast" unless cask.appcast.checkpoint
+    end
 
-  def check_appcast_http_code
-    odebug "Verifying appcast returns 200 HTTP response code"
-    result = @command.run("/usr/bin/curl", args: ["--compressed", "--location", "--user-agent", Hbc::URL::FAKE_USER_AGENT, "--output", "/dev/null", "--write-out", "%{http_code}", cask.appcast], print_stderr: false)
-    if result.success?
-      http_code = result.stdout.chomp
-      add_warning "unexpected HTTP response code retrieving appcast: #{http_code}" unless http_code == "200"
-    else
-      add_warning "error retrieving appcast: #{result.stderr}"
+    def check_appcast_http_code
+      odebug "Verifying appcast returns 200 HTTP response code"
+      result = @command.run("/usr/bin/curl", args: ["--compressed", "--location", "--user-agent", URL::FAKE_USER_AGENT, "--output", "/dev/null", "--write-out", "%{http_code}", cask.appcast], print_stderr: false)
+      if result.success?
+        http_code = result.stdout.chomp
+        add_warning "unexpected HTTP response code retrieving appcast: #{http_code}" unless http_code == "200"
+      else
+        add_warning "error retrieving appcast: #{result.stderr}"
+      end
     end
-  end
 
-  def check_appcast_checkpoint_accuracy
-    odebug "Verifying appcast checkpoint is accurate"
-    result = @command.run("/usr/bin/curl", args: ["--compressed", "--location", "--user-agent", Hbc::URL::FAKE_USER_AGENT, cask.appcast], print_stderr: false)
-    if result.success?
-      processed_appcast_text = result.stdout.gsub(%r{<pubDate>[^<]*</pubDate>}, "")
-      # This step is necessary to replicate running `sed` from the command line
-      processed_appcast_text << "\n" unless processed_appcast_text.end_with?("\n")
-      expected = cask.appcast.checkpoint
-      actual = Digest::SHA2.hexdigest(processed_appcast_text)
-      add_warning <<-EOS.undent unless expected == actual
-        appcast checkpoint mismatch
-        Expected: #{expected}
-        Actual: #{actual}
-      EOS
-    else
-      add_warning "error retrieving appcast: #{result.stderr}"
+    def check_appcast_checkpoint_accuracy
+      odebug "Verifying appcast checkpoint is accurate"
+      result = @command.run("/usr/bin/curl", args: ["--compressed", "--location", "--user-agent", URL::FAKE_USER_AGENT, cask.appcast], print_stderr: false)
+      if result.success?
+        processed_appcast_text = result.stdout.gsub(%r{<pubDate>[^<]*</pubDate>}, "")
+        # This step is necessary to replicate running `sed` from the command line
+        processed_appcast_text << "\n" unless processed_appcast_text.end_with?("\n")
+        expected = cask.appcast.checkpoint
+        actual = Digest::SHA2.hexdigest(processed_appcast_text)
+        add_warning <<-EOS.undent unless expected == actual
+          appcast checkpoint mismatch
+          Expected: #{expected}
+          Actual: #{actual}
+        EOS
+      else
+        add_warning "error retrieving appcast: #{result.stderr}"
+      end
     end
-  end
 
-  def check_url
-    return unless cask.url
-    check_download_url_format
-  end
+    def check_url
+      return unless cask.url
+      check_download_url_format
+    end
 
-  def check_download_url_format
-    odebug "Auditing URL format"
-    if bad_sourceforge_url?
-      add_warning "SourceForge URL format incorrect. See https://github.com/caskroom/homebrew-cask/blob/master/doc/cask_language_reference/stanzas/url.md#sourceforgeosdn-urls"
-    elsif bad_osdn_url?
-      add_warning "OSDN URL format incorrect. See https://github.com/caskroom/homebrew-cask/blob/master/doc/cask_language_reference/stanzas/url.md#sourceforgeosdn-urls"
+    def check_download_url_format
+      odebug "Auditing URL format"
+      if bad_sourceforge_url?
+        add_warning "SourceForge URL format incorrect. See https://github.com/caskroom/homebrew-cask/blob/master/doc/cask_language_reference/stanzas/url.md#sourceforgeosdn-urls"
+      elsif bad_osdn_url?
+        add_warning "OSDN URL format incorrect. See https://github.com/caskroom/homebrew-cask/blob/master/doc/cask_language_reference/stanzas/url.md#sourceforgeosdn-urls"
+      end
     end
-  end
 
-  def bad_url_format?(regex, valid_formats_array)
-    return false unless cask.url.to_s =~ regex
-    valid_formats_array.none? { |format| cask.url.to_s =~ format }
-  end
+    def bad_url_format?(regex, valid_formats_array)
+      return false unless cask.url.to_s =~ regex
+      valid_formats_array.none? { |format| cask.url.to_s =~ format }
+    end
 
-  def bad_sourceforge_url?
-    bad_url_format?(%r{sourceforge},
-                    [
-                      %r{\Ahttps://sourceforge\.net/projects/[^/]+/files/latest/download\Z},
-                      %r{\Ahttps://downloads\.sourceforge\.net/(?!(project|sourceforge)\/)},
-                      # special cases: cannot find canonical format URL
-                      %r{\Ahttps?://brushviewer\.sourceforge\.net/brushviewql\.zip\Z},
-                      %r{\Ahttps?://doublecommand\.sourceforge\.net/files/},
-                      %r{\Ahttps?://excalibur\.sourceforge\.net/get\.php\?id=},
-                    ])
-  end
+    def bad_sourceforge_url?
+      bad_url_format?(%r{sourceforge},
+                      [
+                        %r{\Ahttps://sourceforge\.net/projects/[^/]+/files/latest/download\Z},
+                        %r{\Ahttps://downloads\.sourceforge\.net/(?!(project|sourceforge)\/)},
+                        # special cases: cannot find canonical format URL
+                        %r{\Ahttps?://brushviewer\.sourceforge\.net/brushviewql\.zip\Z},
+                        %r{\Ahttps?://doublecommand\.sourceforge\.net/files/},
+                        %r{\Ahttps?://excalibur\.sourceforge\.net/get\.php\?id=},
+                      ])
+    end
 
-  def bad_osdn_url?
-    bad_url_format?(%r{osd}, [%r{\Ahttps?://([^/]+.)?dl\.osdn\.jp/}])
-  end
+    def bad_osdn_url?
+      bad_url_format?(%r{osd}, [%r{\Ahttps?://([^/]+.)?dl\.osdn\.jp/}])
+    end
 
-  def check_generic_artifacts
-    cask.artifacts[:artifact].each do |source, target_hash|
-      unless target_hash.is_a?(Hash) && target_hash[:target]
-        add_error "target required for generic artifact #{source}"
-        next
+    def check_generic_artifacts
+      cask.artifacts[:artifact].each do |source, target_hash|
+        unless target_hash.is_a?(Hash) && target_hash[:target]
+          add_error "target required for generic artifact #{source}"
+          next
+        end
+        add_error "target must be absolute path for generic artifact #{source}" unless Pathname.new(target_hash[:target]).absolute?
       end
-      add_error "target must be absolute path for generic artifact #{source}" unless Pathname.new(target_hash[:target]).absolute?
     end
-  end
 
-  def check_token_conflicts
-    return unless check_token_conflicts?
-    return unless core_formula_names.include?(cask.token)
-    add_warning "possible duplicate, cask token conflicts with Homebrew core formula: #{core_formula_url}"
-  end
+    def check_token_conflicts
+      return unless check_token_conflicts?
+      return unless core_formula_names.include?(cask.token)
+      add_warning "possible duplicate, cask token conflicts with Homebrew core formula: #{core_formula_url}"
+    end
 
-  def core_tap
-    @core_tap ||= CoreTap.instance
-  end
+    def core_tap
+      @core_tap ||= CoreTap.instance
+    end
 
-  def core_formula_names
-    core_tap.formula_names
-  end
+    def core_formula_names
+      core_tap.formula_names
+    end
 
-  def core_formula_url
-    "#{core_tap.default_remote}/blob/master/Formula/#{cask.token}.rb"
-  end
+    def core_formula_url
+      "#{core_tap.default_remote}/blob/master/Formula/#{cask.token}.rb"
+    end
 
-  def check_download
-    return unless download && cask.url
-    odebug "Auditing download"
-    downloaded_path = download.perform
-    Hbc::Verify.all(cask, downloaded_path)
-  rescue => e
-    add_error "download not possible: #{e.message}"
+    def check_download
+      return unless download && cask.url
+      odebug "Auditing download"
+      downloaded_path = download.perform
+      Verify.all(cask, downloaded_path)
+    rescue => e
+      add_error "download not possible: #{e.message}"
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/auditor.rb b/Library/Homebrew/cask/lib/hbc/auditor.rb
index 89947c1aa..6b0c1c476 100644
--- a/Library/Homebrew/cask/lib/hbc/auditor.rb
+++ b/Library/Homebrew/cask/lib/hbc/auditor.rb
@@ -1,10 +1,12 @@
-class Hbc::Auditor
-  def self.audit(cask, audit_download: false, check_token_conflicts: false)
-    download = audit_download && Hbc::Download.new(cask)
-    audit = Hbc::Audit.new(cask, download:              download,
-                                 check_token_conflicts: check_token_conflicts)
-    audit.run!
-    puts audit.summary
-    audit.success?
+module Hbc
+  class Auditor
+    def self.audit(cask, audit_download: false, check_token_conflicts: false)
+      download = audit_download && Download.new(cask)
+      audit = Audit.new(cask, download:              download,
+                              check_token_conflicts: check_token_conflicts)
+      audit.run!
+      puts audit.summary
+      audit.success?
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cache.rb b/Library/Homebrew/cask/lib/hbc/cache.rb
index 9fc5fe0f3..db3ec536b 100644
--- a/Library/Homebrew/cask/lib/hbc/cache.rb
+++ b/Library/Homebrew/cask/lib/hbc/cache.rb
@@ -1,21 +1,23 @@
-module Hbc::Cache
-  module_function
+module Hbc
+  module Cache
+    module_function
 
-  def ensure_cache_exists
-    return if Hbc.cache.exist?
-    odebug "Creating Cache at #{Hbc.cache}"
-    Hbc.cache.mkpath
-  end
+    def ensure_cache_exists
+      return if Hbc.cache.exist?
 
-  def migrate_legacy_cache
-    if Hbc.legacy_cache.exist?
-      ohai "Migrating cached files to #{Hbc.cache}..."
+      odebug "Creating Cache at #{Hbc.cache}"
+      Hbc.cache.mkpath
+    end
 
+    def migrate_legacy_cache
+      return unless Hbc.legacy_cache.exist?
+
+      ohai "Migrating cached files to #{Hbc.cache}..."
       Hbc.legacy_cache.children.select(&:symlink?).each do |symlink|
         file = symlink.readlink
 
         new_name = file.basename
-                       .sub(%r{\-((?:(\d|#{Hbc::DSL::Version::DIVIDER_REGEX})*\-\2*)*[^\-]+)$}x,
+                       .sub(%r{\-((?:(\d|#{DSL::Version::DIVIDER_REGEX})*\-\2*)*[^\-]+)$}x,
                             '--\1')
 
         renamed_file = Hbc.cache.join(new_name)
diff --git a/Library/Homebrew/cask/lib/hbc/cask.rb b/Library/Homebrew/cask/lib/hbc/cask.rb
index fd13a6fe7..756b05b83 100644
--- a/Library/Homebrew/cask/lib/hbc/cask.rb
+++ b/Library/Homebrew/cask/lib/hbc/cask.rb
@@ -2,92 +2,95 @@ require "forwardable"
 
 require "hbc/dsl"
 
-class Hbc::Cask
-  extend Forwardable
+module Hbc
+  class Cask
+    extend Forwardable
 
-  attr_reader :token, :sourcefile_path
-  def initialize(token, sourcefile_path: nil, dsl: nil, &block)
-    @token = token
-    @sourcefile_path = sourcefile_path
-    @dsl = dsl || Hbc::DSL.new(@token)
-    @dsl.instance_eval(&block) if block_given?
-  end
-
-  Hbc::DSL::DSL_METHODS.each do |method_name|
-    define_method(method_name) { @dsl.send(method_name) }
-  end
+    attr_reader :token, :sourcefile_path
+    def initialize(token, sourcefile_path: nil, dsl: nil, &block)
+      @token = token
+      @sourcefile_path = sourcefile_path
+      @dsl = dsl || DSL.new(@token)
+      @dsl.instance_eval(&block) if block_given?
+    end
 
-  METADATA_SUBDIR = ".metadata".freeze
+    DSL::DSL_METHODS.each do |method_name|
+      define_method(method_name) { @dsl.send(method_name) }
+    end
 
-  def metadata_master_container_path
-    @metadata_master_container_path ||= caskroom_path.join(METADATA_SUBDIR)
-  end
+    METADATA_SUBDIR = ".metadata".freeze
 
-  def metadata_versioned_container_path
-    cask_version = version ? version : :unknown
-    metadata_master_container_path.join(cask_version.to_s)
-  end
-
-  def metadata_path(timestamp = :latest, create = false)
-    return nil unless metadata_versioned_container_path.respond_to?(:join)
-    if create && timestamp == :latest
-      raise Hbc::CaskError, "Cannot create metadata path when timestamp is :latest"
+    def metadata_master_container_path
+      @metadata_master_container_path ||= caskroom_path.join(METADATA_SUBDIR)
     end
-    path = if timestamp == :latest
-             Pathname.glob(metadata_versioned_container_path.join("*")).sort.last
-           elsif timestamp == :now
-             Hbc::Utils.nowstamp_metadata_path(metadata_versioned_container_path)
-           else
-             metadata_versioned_container_path.join(timestamp)
-           end
-    if create
-      odebug "Creating metadata directory #{path}"
-      FileUtils.mkdir_p path
+
+    def metadata_versioned_container_path
+      cask_version = version ? version : :unknown
+      metadata_master_container_path.join(cask_version.to_s)
     end
-    path
-  end
 
-  def metadata_subdir(leaf, timestamp = :latest, create = false)
-    if create && timestamp == :latest
-      raise Hbc::CaskError, "Cannot create metadata subdir when timestamp is :latest"
+    def metadata_path(timestamp = :latest, create = false)
+      return nil unless metadata_versioned_container_path.respond_to?(:join)
+      if create && timestamp == :latest
+        raise CaskError, "Cannot create metadata path when timestamp is :latest"
+      end
+      path = if timestamp == :latest
+               Pathname.glob(metadata_versioned_container_path.join("*")).sort.last
+             elsif timestamp == :now
+               Utils.nowstamp_metadata_path(metadata_versioned_container_path)
+             else
+               metadata_versioned_container_path.join(timestamp)
+             end
+      if create
+        odebug "Creating metadata directory #{path}"
+        FileUtils.mkdir_p path
+      end
+      path
     end
-    unless leaf.respond_to?(:length) && !leaf.empty?
-      raise Hbc::CaskError, "Cannot create metadata subdir for empty leaf"
+
+    def metadata_subdir(leaf, timestamp = :latest, create = false)
+      if create && timestamp == :latest
+        raise CaskError, "Cannot create metadata subdir when timestamp is :latest"
+      end
+      unless leaf.respond_to?(:length) && !leaf.empty?
+        raise CaskError, "Cannot create metadata subdir for empty leaf"
+      end
+      parent = metadata_path(timestamp, create)
+      return nil unless parent.respond_to?(:join)
+      subdir = parent.join(leaf)
+      if create
+        odebug "Creating metadata subdirectory #{subdir}"
+        FileUtils.mkdir_p subdir
+      end
+      subdir
     end
-    parent = metadata_path(timestamp, create)
-    return nil unless parent.respond_to?(:join)
-    subdir = parent.join(leaf)
-    if create
-      odebug "Creating metadata subdirectory #{subdir}"
-      FileUtils.mkdir_p subdir
+
+    def timestamped_versions
+      Pathname.glob(metadata_master_container_path.join("*", "*"))
+              .map { |p| p.relative_path_from(metadata_master_container_path) }
+              .sort_by(&:basename) # sort by timestamp
+              .map(&:split)
     end
-    subdir
-  end
 
-  def timestamped_versions
-    Pathname.glob(metadata_master_container_path.join("*", "*"))
-            .map { |p| p.relative_path_from(metadata_master_container_path) }
-            .sort_by(&:basename) # sort by timestamp
-            .map(&:split)
-  end
+    def versions
+      timestamped_versions.map(&:first)
+                          .reverse
+                          .uniq
+                          .reverse
+    end
 
-  def versions
-    timestamped_versions.map(&:first)
-                        .reverse
-                        .uniq
-                        .reverse
-  end
+    def installed?
+      !versions.empty?
+    end
 
-  def installed?
-    !versions.empty?
-  end
+    def to_s
+      @token
+    end
 
-  def to_s
-    @token
-  end
+    def dumpcask
+      return unless Hbc.respond_to?(:debug)
+      return unless Hbc.debug
 
-  def dumpcask
-    if Hbc.respond_to?(:debug) && Hbc.debug
       odebug "Cask instance dumps in YAML:"
       odebug "Cask instance toplevel:", to_yaml
       [
diff --git a/Library/Homebrew/cask/lib/hbc/cask_dependencies.rb b/Library/Homebrew/cask/lib/hbc/cask_dependencies.rb
index 6cbfd05af..4b4f042d8 100644
--- a/Library/Homebrew/cask/lib/hbc/cask_dependencies.rb
+++ b/Library/Homebrew/cask/lib/hbc/cask_dependencies.rb
@@ -1,33 +1,35 @@
 require "hbc/topological_hash"
 
-class Hbc::CaskDependencies
-  attr_reader :cask, :graph, :sorted
+module Hbc
+  class CaskDependencies
+    attr_reader :cask, :graph, :sorted
 
-  def initialize(cask)
-    @cask = cask
-    @graph = graph_dependencies
-    @sorted = sort
-  end
+    def initialize(cask)
+      @cask = cask
+      @graph = graph_dependencies
+      @sorted = sort
+    end
 
-  def graph_dependencies
-    deps_in = ->(csk) { csk.depends_on ? csk.depends_on.cask || [] : [] }
-    walk = lambda { |acc, deps|
-      deps.each do |dep|
-        next if acc.key?(dep)
-        succs = deps_in.call Hbc.load(dep)
-        acc[dep] = succs
-        walk.call(acc, succs)
-      end
-      acc
-    }
+    def graph_dependencies
+      deps_in = ->(csk) { csk.depends_on ? csk.depends_on.cask || [] : [] }
+      walk = lambda { |acc, deps|
+        deps.each do |dep|
+          next if acc.key?(dep)
+          succs = deps_in.call Hbc.load(dep)
+          acc[dep] = succs
+          walk.call(acc, succs)
+        end
+        acc
+      }
 
-    graphed = walk.call({}, @cask.depends_on.cask)
-    Hbc::TopologicalHash[graphed]
-  end
+      graphed = walk.call({}, @cask.depends_on.cask)
+      TopologicalHash[graphed]
+    end
 
-  def sort
-    @graph.tsort
-  rescue TSort::Cyclic
-    raise Hbc::CaskCyclicCaskDependencyError, @cask.token
+    def sort
+      @graph.tsort
+    rescue TSort::Cyclic
+      raise CaskCyclicCaskDependencyError, @cask.token
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/caskroom.rb b/Library/Homebrew/cask/lib/hbc/caskroom.rb
index 7d02f3fa4..583cac34a 100644
--- a/Library/Homebrew/cask/lib/hbc/caskroom.rb
+++ b/Library/Homebrew/cask/lib/hbc/caskroom.rb
@@ -1,18 +1,26 @@
-module Hbc::Caskroom
-  module_function
+module Hbc
+  module Caskroom
+    module_function
+
+    def migrate_caskroom_from_repo_to_prefix
+      repo_caskroom = Hbc.homebrew_repository.join("Caskroom")
+      return if Hbc.caskroom.exist?
+      return unless repo_caskroom.directory?
 
-  def migrate_caskroom_from_repo_to_prefix
-    repo_caskroom = Hbc.homebrew_repository.join("Caskroom")
-    if !Hbc.caskroom.exist? && repo_caskroom.directory?
       ohai "Moving Caskroom from HOMEBREW_REPOSITORY to HOMEBREW_PREFIX"
-      FileUtils.mv repo_caskroom, Hbc.caskroom
+
+      if Hbc.caskroom.parent.writable?
+        FileUtils.mv repo_caskroom, Hbc.caskroom
+      else
+        opoo "#{Hbc.caskroom.parent} is not writable, sudo is needed to move the Caskroom."
+        system "/usr/bin/sudo", "--", "/bin/mv", "--", repo_caskroom.to_s, Hbc.caskroom.parent.to_s
+      end
     end
-  end
 
-  def ensure_caskroom_exists
-    unless Hbc.caskroom.exist?
-      ohai "Creating Caskroom at #{Hbc.caskroom}"
+    def ensure_caskroom_exists
+      return if Hbc.caskroom.exist?
 
+      ohai "Creating Caskroom at #{Hbc.caskroom}"
       if Hbc.caskroom.parent.writable?
         Hbc.caskroom.mkpath
       else
@@ -28,7 +36,7 @@ module Hbc::Caskroom
         # sudo in system is rude.
         system "/usr/bin/sudo", "--", "/bin/mkdir", "-p", "--", Hbc.caskroom
         unless Hbc.caskroom.parent == toplevel_dir
-          system "/usr/bin/sudo", "--", "/usr/sbin/chown", "-R", "--", "#{Hbc::Utils.current_user}:staff", Hbc.caskroom.parent.to_s
+          system "/usr/bin/sudo", "--", "/usr/sbin/chown", "-R", "--", "#{Utils.current_user}:staff", Hbc.caskroom.parent.to_s
         end
       end
     end
diff --git a/Library/Homebrew/cask/lib/hbc/caveats.rb b/Library/Homebrew/cask/lib/hbc/caveats.rb
index 04bbcf218..a85429151 100644
--- a/Library/Homebrew/cask/lib/hbc/caveats.rb
+++ b/Library/Homebrew/cask/lib/hbc/caveats.rb
@@ -1,12 +1,14 @@
-class Hbc::Caveats
-  def initialize(block)
-    @block = block
-  end
+module Hbc
+  class Caveats
+    def initialize(block)
+      @block = block
+    end
 
-  def eval_and_print(cask)
-    dsl = Hbc::DSL::Caveats.new(cask)
-    retval = dsl.instance_eval(&@block)
-    return if retval.nil?
-    puts retval.to_s.sub(%r{[\r\n \t]*\Z}, "\n\n")
+    def eval_and_print(cask)
+      dsl = DSL::Caveats.new(cask)
+      retval = dsl.instance_eval(&@block)
+      return if retval.nil?
+      puts retval.to_s.sub(%r{[\r\n \t]*\Z}, "\n\n")
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/checkable.rb b/Library/Homebrew/cask/lib/hbc/checkable.rb
index 9c12f80ca..42c47ea78 100644
--- a/Library/Homebrew/cask/lib/hbc/checkable.rb
+++ b/Library/Homebrew/cask/lib/hbc/checkable.rb
@@ -1,51 +1,53 @@
-module Hbc::Checkable
-  def errors
-    Array(@errors)
-  end
+module Hbc
+  module Checkable
+    def errors
+      Array(@errors)
+    end
 
-  def warnings
-    Array(@warnings)
-  end
+    def warnings
+      Array(@warnings)
+    end
 
-  def add_error(message)
-    @errors ||= []
-    @errors << message
-  end
+    def add_error(message)
+      @errors ||= []
+      @errors << message
+    end
 
-  def add_warning(message)
-    @warnings ||= []
-    @warnings << message
-  end
+    def add_warning(message)
+      @warnings ||= []
+      @warnings << message
+    end
 
-  def errors?
-    Array(@errors).any?
-  end
+    def errors?
+      Array(@errors).any?
+    end
 
-  def warnings?
-    Array(@warnings).any?
-  end
+    def warnings?
+      Array(@warnings).any?
+    end
 
-  def result
-    if errors?
-      "#{Tty.red}failed#{Tty.reset}"
-    elsif warnings?
-      "#{Tty.yellow}warning#{Tty.reset}"
-    else
-      "#{Tty.green}passed#{Tty.reset}"
+    def result
+      if errors?
+        "#{Tty.red}failed#{Tty.reset}"
+      elsif warnings?
+        "#{Tty.yellow}warning#{Tty.reset}"
+      else
+        "#{Tty.green}passed#{Tty.reset}"
+      end
     end
-  end
 
-  def summary
-    summary = ["#{summary_header}: #{result}"]
+    def summary
+      summary = ["#{summary_header}: #{result}"]
 
-    errors.each do |error|
-      summary << " #{Tty.red}-#{Tty.reset} #{error}"
-    end
+      errors.each do |error|
+        summary << " #{Tty.red}-#{Tty.reset} #{error}"
+      end
 
-    warnings.each do |warning|
-      summary << " #{Tty.yellow}-#{Tty.reset} #{warning}"
-    end
+      warnings.each do |warning|
+        summary << " #{Tty.yellow}-#{Tty.reset} #{warning}"
+      end
 
-    summary.join("\n")
+      summary.join("\n")
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli.rb b/Library/Homebrew/cask/lib/hbc/cli.rb
index 1378176da..3f67e131d 100644
--- a/Library/Homebrew/cask/lib/hbc/cli.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli.rb
@@ -1,5 +1,3 @@
-class Hbc::CLI; end
-
 require "optparse"
 require "shellwords"
 
@@ -28,248 +26,250 @@ require "hbc/cli/internal_dump"
 require "hbc/cli/internal_help"
 require "hbc/cli/internal_stanza"
 
-class Hbc::CLI
-  ALIASES = {
-              "ls"       => "list",
-              "homepage" => "home",
-              "-S"       => "search",    # verb starting with "-" is questionable
-              "up"       => "update",
-              "instal"   => "install",   # gem does the same
-              "rm"       => "uninstall",
-              "remove"   => "uninstall",
-              "abv"      => "info",
-              "dr"       => "doctor",
-              # aliases from Homebrew that we don't (yet) support
-              # 'ln'          => 'link',
-              # 'configure'   => 'diy',
-              # '--repo'      => '--repository',
-              # 'environment' => '--env',
-              # '-c1'         => '--config',
-            }.freeze
+module Hbc
+  class CLI
+    ALIASES = {
+                "ls"       => "list",
+                "homepage" => "home",
+                "-S"       => "search",    # verb starting with "-" is questionable
+                "up"       => "update",
+                "instal"   => "install",   # gem does the same
+                "rm"       => "uninstall",
+                "remove"   => "uninstall",
+                "abv"      => "info",
+                "dr"       => "doctor",
+                # aliases from Homebrew that we don't (yet) support
+                # 'ln'          => 'link',
+                # 'configure'   => 'diy',
+                # '--repo'      => '--repository',
+                # 'environment' => '--env',
+                # '-c1'         => '--config',
+              }.freeze
+
+    OPTIONS = {
+                "--caskroom="             => :caskroom=,
+                "--appdir="               => :appdir=,
+                "--colorpickerdir="       => :colorpickerdir=,
+                "--prefpanedir="          => :prefpanedir=,
+                "--qlplugindir="          => :qlplugindir=,
+                "--fontdir="              => :fontdir=,
+                "--servicedir="           => :servicedir=,
+                "--input_methoddir="      => :input_methoddir=,
+                "--internet_plugindir="   => :internet_plugindir=,
+                "--audio_unit_plugindir=" => :audio_unit_plugindir=,
+                "--vst_plugindir="        => :vst_plugindir=,
+                "--vst3_plugindir="       => :vst3_plugindir=,
+                "--screen_saverdir="      => :screen_saverdir=,
+              }.freeze
 
-  OPTIONS = {
-              "--caskroom="             => :caskroom=,
-              "--appdir="               => :appdir=,
-              "--colorpickerdir="       => :colorpickerdir=,
-              "--prefpanedir="          => :prefpanedir=,
-              "--qlplugindir="          => :qlplugindir=,
-              "--fontdir="              => :fontdir=,
-              "--servicedir="           => :servicedir=,
-              "--input_methoddir="      => :input_methoddir=,
-              "--internet_plugindir="   => :internet_plugindir=,
-              "--audio_unit_plugindir=" => :audio_unit_plugindir=,
-              "--vst_plugindir="        => :vst_plugindir=,
-              "--vst3_plugindir="       => :vst3_plugindir=,
-              "--screen_saverdir="      => :screen_saverdir=,
+    FLAGS = {
+              "--no-binaries" => :no_binaries=,
+              "--debug"       => :debug=,
+              "--verbose"     => :verbose=,
+              "--outdated"    => :cleanup_outdated=,
+              "--help"        => :help=,
             }.freeze
 
-  FLAGS = {
-            "--no-binaries" => :no_binaries=,
-            "--debug"       => :debug=,
-            "--verbose"     => :verbose=,
-            "--outdated"    => :cleanup_outdated=,
-            "--help"        => :help=,
-          }.freeze
+    def self.command_classes
+      @command_classes ||= self.constants
+                               .map(&method(:const_get))
+                               .select { |sym| sym.respond_to?(:run) }
+    end
 
-  def self.command_classes
-    @command_classes ||= Hbc::CLI.constants
-                                 .map(&Hbc::CLI.method(:const_get))
-                                 .select { |sym| sym.respond_to?(:run) }
-  end
+    def self.commands
+      @commands ||= command_classes.map(&:command_name)
+    end
 
-  def self.commands
-    @commands ||= command_classes.map(&:command_name)
-  end
+    def self.lookup_command(command_string)
+      @lookup ||= Hash[commands.zip(command_classes)]
+      command_string = ALIASES.fetch(command_string, command_string)
+      @lookup.fetch(command_string, command_string)
+    end
 
-  def self.lookup_command(command_string)
-    @lookup ||= Hash[commands.zip(command_classes)]
-    command_string = ALIASES.fetch(command_string, command_string)
-    @lookup.fetch(command_string, command_string)
-  end
+    # modified from Homebrew
+    def self.require?(path)
+      require path
+      true # OK if already loaded
+    rescue LoadError => e
+      # HACK: :( because we should raise on syntax errors
+      #       but not if the file doesn't exist.
+      # TODO: make robust!
+      raise unless e.to_s.include? path
+    end
 
-  # modified from Homebrew
-  def self.require?(path)
-    require path
-    true # OK if already loaded
-  rescue LoadError => e
-    # HACK: :( because we should raise on syntax errors
-    #       but not if the file doesn't exist.
-    # TODO: make robust!
-    raise unless e.to_s.include? path
-  end
+    def self.should_init?(command)
+      (command.is_a? Class) && (command < CLI::Base) && command.needs_init?
+    end
 
-  def self.should_init?(command)
-    (command.is_a? Class) && (command < Hbc::CLI::Base) && command.needs_init?
-  end
+    def self.run_command(command, *rest)
+      if command.respond_to?(:run)
+        # usual case: built-in command verb
+        command.run(*rest)
+      elsif require? Utils.which("brewcask-#{command}.rb").to_s
+        # external command as Ruby library on PATH, Homebrew-style
+      elsif command.to_s.include?("/") && require?(command.to_s)
+        # external command as Ruby library with literal path, useful
+        # for development and troubleshooting
+        sym = Pathname.new(command.to_s).basename(".rb").to_s.capitalize
+        klass = begin
+                  self.const_get(sym)
+                rescue NameError
+                  nil
+                end
 
-  def self.run_command(command, *rest)
-    if command.respond_to?(:run)
-      # usual case: built-in command verb
-      command.run(*rest)
-    elsif require? Hbc::Utils.which("brewcask-#{command}.rb").to_s
-      # external command as Ruby library on PATH, Homebrew-style
-    elsif command.to_s.include?("/") && require?(command.to_s)
-      # external command as Ruby library with literal path, useful
-      # for development and troubleshooting
-      sym = Pathname.new(command.to_s).basename(".rb").to_s.capitalize
-      klass = begin
-                Hbc::CLI.const_get(sym)
-              rescue NameError
-                nil
-              end
-      if klass.respond_to?(:run)
-        # invoke "run" on a Ruby library which follows our coding conventions
-        klass.run(*rest)
+        if klass.respond_to?(:run)
+          # invoke "run" on a Ruby library which follows our coding conventions
+          # other Ruby libraries must do everything via "require"
+          klass.run(*rest)
+        end
+      elsif Utils.which "brewcask-#{command}"
+        # arbitrary external executable on PATH, Homebrew-style
+        exec "brewcask-#{command}", *ARGV[1..-1]
+      elsif Pathname.new(command.to_s).executable? &&
+            command.to_s.include?("/") &&
+            !command.to_s.match(%r{\.rb$})
+        # arbitrary external executable with literal path, useful
+        # for development and troubleshooting
+        exec command, *ARGV[1..-1]
       else
-        # other Ruby libraries must do everything via "require"
+        # failure
+        NullCommand.new(command).run
       end
-    elsif Hbc::Utils.which "brewcask-#{command}"
-      # arbitrary external executable on PATH, Homebrew-style
-      exec "brewcask-#{command}", *ARGV[1..-1]
-    elsif Pathname.new(command.to_s).executable? &&
-          command.to_s.include?("/") &&
-          !command.to_s.match(%r{\.rb$})
-      # arbitrary external executable with literal path, useful
-      # for development and troubleshooting
-      exec command, *ARGV[1..-1]
-    else
-      # failure
-      Hbc::CLI::NullCommand.new(command).run
     end
-  end
 
-  def self.process(arguments)
-    command_string, *rest = *arguments
-    rest = process_options(rest)
-    command = Hbc.help ? "help" : lookup_command(command_string)
-    Hbc.default_tap.install unless Hbc.default_tap.installed?
-    Hbc.init if should_init?(command)
-    run_command(command, *rest)
-  rescue Hbc::CaskError, Hbc::CaskSha256MismatchError => e
-    msg = e.message
-    msg << e.backtrace.join("\n") if Hbc.debug
-    onoe msg
-    exit 1
-  rescue StandardError, ScriptError, NoMemoryError => e
-    msg = e.message
-    msg << Hbc::Utils.error_message_with_suggestions
-    msg << e.backtrace.join("\n")
-    onoe msg
-    exit 1
-  end
-
-  def self.nice_listing(cask_list)
-    cask_taps = {}
-    cask_list.each do |c|
-      user, repo, token = c.split "/"
-      repo.sub!(%r{^homebrew-}i, "")
-      cask_taps[token] ||= []
-      cask_taps[token].push "#{user}/#{repo}"
+    def self.process(arguments)
+      command_string, *rest = *arguments
+      rest = process_options(rest)
+      command = Hbc.help ? "help" : lookup_command(command_string)
+      Hbc.default_tap.install unless Hbc.default_tap.installed?
+      Hbc.init if should_init?(command)
+      run_command(command, *rest)
+    rescue CaskError, CaskSha256MismatchError => e
+      msg = e.message
+      msg << e.backtrace.join("\n") if Hbc.debug
+      onoe msg
+      exit 1
+    rescue StandardError, ScriptError, NoMemoryError => e
+      msg = e.message
+      msg << Utils.error_message_with_suggestions
+      msg << e.backtrace.join("\n")
+      onoe msg
+      exit 1
     end
-    list = []
-    cask_taps.each do |token, taps|
-      if taps.length == 1
-        list.push token
-      else
-        taps.each { |r| list.push [r, token].join "/" }
+
+    def self.nice_listing(cask_list)
+      cask_taps = {}
+      cask_list.each do |c|
+        user, repo, token = c.split "/"
+        repo.sub!(%r{^homebrew-}i, "")
+        cask_taps[token] ||= []
+        cask_taps[token].push "#{user}/#{repo}"
+      end
+      list = []
+      cask_taps.each do |token, taps|
+        if taps.length == 1
+          list.push token
+        else
+          taps.each { |r| list.push [r, token].join "/" }
+        end
       end
+      list.sort
     end
-    list.sort
-  end
 
-  def self.parser
-    # If you modify these arguments, please update USAGE.md
-    @parser ||= OptionParser.new do |opts|
-      OPTIONS.each do |option, method|
-        opts.on("#{option}" "PATH", Pathname) do |path|
-          Hbc.public_send(method, path)
+    def self.parser
+      # If you modify these arguments, please update USAGE.md
+      @parser ||= OptionParser.new do |opts|
+        OPTIONS.each do |option, method|
+          opts.on("#{option}" "PATH", Pathname) do |path|
+            Hbc.public_send(method, path)
+          end
         end
-      end
 
-      opts.on("--binarydir=PATH") do
-        opoo <<-EOS.undent
-          Option --binarydir is obsolete!
-          Homebrew-Cask now uses the same location as your Homebrew installation for executable links.
-        EOS
-      end
+        opts.on("--binarydir=PATH") do
+          opoo <<-EOS.undent
+            Option --binarydir is obsolete!
+            Homebrew-Cask now uses the same location as your Homebrew installation for executable links.
+          EOS
+        end
 
-      FLAGS.each do |flag, method|
-        opts.on(flag) do
-          Hbc.public_send(method, true)
+        FLAGS.each do |flag, method|
+          opts.on(flag) do
+            Hbc.public_send(method, true)
+          end
         end
-      end
 
-      opts.on("--version") do
-        raise OptionParser::InvalidOption # override default handling of --version
+        opts.on("--version") do
+          raise OptionParser::InvalidOption # override default handling of --version
+        end
       end
     end
-  end
 
-  def self.process_options(args)
-    all_args = Shellwords.shellsplit(ENV["HOMEBREW_CASK_OPTS"] || "") + args
-    remaining = []
-    until all_args.empty?
-      begin
-        head = all_args.shift
-        remaining.concat(parser.parse([head]))
-      rescue OptionParser::InvalidOption
-        remaining << head
-        retry
-      rescue OptionParser::MissingArgument
-        raise Hbc::CaskError, "The option '#{head}' requires an argument"
-      rescue OptionParser::AmbiguousOption
-        raise Hbc::CaskError, "There is more than one possible option that starts with '#{head}'"
+    def self.process_options(args)
+      all_args = Shellwords.shellsplit(ENV["HOMEBREW_CASK_OPTS"] || "") + args
+      remaining = []
+      until all_args.empty?
+        begin
+          head = all_args.shift
+          remaining.concat(parser.parse([head]))
+        rescue OptionParser::InvalidOption
+          remaining << head
+          retry
+        rescue OptionParser::MissingArgument
+          raise CaskError, "The option '#{head}' requires an argument"
+        rescue OptionParser::AmbiguousOption
+          raise CaskError, "There is more than one possible option that starts with '#{head}'"
+        end
       end
-    end
 
-    # for compat with Homebrew, not certain if this is desirable
-    Hbc.verbose = true if !ENV["VERBOSE"].nil? || !ENV["HOMEBREW_VERBOSE"].nil?
+      # for compat with Homebrew, not certain if this is desirable
+      Hbc.verbose = true if !ENV["VERBOSE"].nil? || !ENV["HOMEBREW_VERBOSE"].nil?
 
-    remaining
-  end
-
-  class NullCommand
-    def initialize(attempted_verb)
-      @attempted_verb = attempted_verb
+      remaining
     end
 
-    def run(*args)
-      if args.include?("--version") || @attempted_verb == "--version"
-        puts Hbc.full_version
-      else
-        purpose
-        usage
-        unless @attempted_verb.to_s.strip.empty? || @attempted_verb == "help"
-          raise Hbc::CaskError, "Unknown command: #{@attempted_verb}"
+    class NullCommand
+      def initialize(attempted_verb)
+        @attempted_verb = attempted_verb
+      end
+
+      def run(*args)
+        if args.include?("--version") || @attempted_verb == "--version"
+          puts Hbc.full_version
+        else
+          purpose
+          usage
+          unless @attempted_verb.to_s.strip.empty? || @attempted_verb == "help"
+            raise CaskError, "Unknown command: #{@attempted_verb}"
+          end
         end
       end
-    end
 
-    def purpose
-      puts <<-EOS.undent
-        brew-cask provides a friendly homebrew-style CLI workflow for the
-        administration of macOS applications distributed as binaries.
+      def purpose
+        puts <<-EOS.undent
+          brew-cask provides a friendly homebrew-style CLI workflow for the
+          administration of macOS applications distributed as binaries.
 
-      EOS
-    end
+        EOS
+      end
 
-    def usage
-      max_command_len = Hbc::CLI.commands.map(&:length).max
+      def usage
+        max_command_len = CLI.commands.map(&:length).max
 
-      puts "Commands:\n\n"
-      Hbc::CLI.command_classes.each do |klass|
-        next unless klass.visible
-        puts "    #{klass.command_name.ljust(max_command_len)}  #{_help_for(klass)}"
+        puts "Commands:\n\n"
+        CLI.command_classes.each do |klass|
+          next unless klass.visible
+          puts "    #{klass.command_name.ljust(max_command_len)}  #{_help_for(klass)}"
+        end
+        puts %Q{\nSee also "man brew-cask"}
       end
-      puts %Q{\nSee also "man brew-cask"}
-    end
 
-    def help
-      ""
-    end
+      def help
+        ""
+      end
 
-    def _help_for(klass)
-      klass.respond_to?(:help) ? klass.help : nil
+      def _help_for(klass)
+        klass.respond_to?(:help) ? klass.help : nil
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/audit.rb b/Library/Homebrew/cask/lib/hbc/cli/audit.rb
index 289547b44..a06f71c60 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/audit.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/audit.rb
@@ -1,52 +1,56 @@
-class Hbc::CLI::Audit < Hbc::CLI::Base
-  def self.help
-    "verifies installability of Casks"
-  end
-
-  def self.run(*args)
-    failed_casks = new(args, Hbc::Auditor).run
-    return if failed_casks.empty?
-    raise Hbc::CaskError, "audit failed for casks: #{failed_casks.join(' ')}"
-  end
-
-  def initialize(args, auditor)
-    @args = args
-    @auditor = auditor
-  end
-
-  def run
-    casks_to_audit.each_with_object([]) do |cask, failed|
-      failed << cask unless audit(cask)
+module Hbc
+  class CLI
+    class Audit < Base
+      def self.help
+        "verifies installability of Casks"
+      end
+
+      def self.run(*args)
+        failed_casks = new(args, Auditor).run
+        return if failed_casks.empty?
+        raise CaskError, "audit failed for casks: #{failed_casks.join(" ")}"
+      end
+
+      def initialize(args, auditor)
+        @args = args
+        @auditor = auditor
+      end
+
+      def run
+        casks_to_audit.each_with_object([]) do |cask, failed|
+          failed << cask unless audit(cask)
+        end
+      end
+
+      def audit(cask)
+        odebug "Auditing Cask #{cask}"
+        @auditor.audit(cask, audit_download:        audit_download?,
+                             check_token_conflicts: check_token_conflicts?)
+      end
+
+      def audit_download?
+        @args.include?("--download")
+      end
+
+      def check_token_conflicts?
+        @args.include?("--token-conflicts")
+      end
+
+      def casks_to_audit
+        if cask_tokens.empty?
+          Hbc.all
+        else
+          cask_tokens.map { |token| Hbc.load(token) }
+        end
+      end
+
+      def cask_tokens
+        @cask_tokens ||= self.class.cask_tokens_from(@args)
+      end
+
+      def self.needs_init?
+        true
+      end
     end
   end
-
-  def audit(cask)
-    odebug "Auditing Cask #{cask}"
-    @auditor.audit(cask, audit_download:        audit_download?,
-                         check_token_conflicts: check_token_conflicts?)
-  end
-
-  def audit_download?
-    @args.include?("--download")
-  end
-
-  def check_token_conflicts?
-    @args.include?("--token-conflicts")
-  end
-
-  def casks_to_audit
-    if cask_tokens.empty?
-      Hbc.all
-    else
-      cask_tokens.map { |token| Hbc.load(token) }
-    end
-  end
-
-  def cask_tokens
-    @cask_tokens ||= self.class.cask_tokens_from(@args)
-  end
-
-  def self.needs_init?
-    true
-  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/base.rb b/Library/Homebrew/cask/lib/hbc/cli/base.rb
index af03969af..6c706d537 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/base.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/base.rb
@@ -1,21 +1,25 @@
-class Hbc::CLI::Base
-  def self.command_name
-    @command_name ||= name.sub(%r{^.*:}, "").gsub(%r{(.)([A-Z])}, '\1_\2').downcase
-  end
+module Hbc
+  class CLI
+    class Base
+      def self.command_name
+        @command_name ||= name.sub(%r{^.*:}, "").gsub(%r{(.)([A-Z])}, '\1_\2').downcase
+      end
 
-  def self.visible
-    true
-  end
+      def self.visible
+        true
+      end
 
-  def self.cask_tokens_from(args)
-    args.reject { |a| a.empty? || a.chars.first == "-" }
-  end
+      def self.cask_tokens_from(args)
+        args.reject { |a| a.empty? || a.chars.first == "-" }
+      end
 
-  def self.help
-    "No help available for the #{command_name} command"
-  end
+      def self.help
+        "No help available for the #{command_name} command"
+      end
 
-  def self.needs_init?
-    false
+      def self.needs_init?
+        false
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/cat.rb b/Library/Homebrew/cask/lib/hbc/cli/cat.rb
index d6d545c3b..75f6c1e91 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/cat.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/cat.rb
@@ -1,15 +1,19 @@
-class Hbc::CLI::Cat < Hbc::CLI::Base
-  def self.run(*args)
-    cask_tokens = cask_tokens_from(args)
-    raise Hbc::CaskUnspecifiedError if cask_tokens.empty?
-    # only respects the first argument
-    cask_token = cask_tokens.first.sub(%r{\.rb$}i, "")
-    cask_path = Hbc.path(cask_token)
-    raise Hbc::CaskUnavailableError, cask_token.to_s unless cask_path.exist?
-    puts File.open(cask_path, &:read)
-  end
+module Hbc
+  class CLI
+    class Cat < Base
+      def self.run(*args)
+        cask_tokens = cask_tokens_from(args)
+        raise CaskUnspecifiedError if cask_tokens.empty?
+        # only respects the first argument
+        cask_token = cask_tokens.first.sub(%r{\.rb$}i, "")
+        cask_path = Hbc.path(cask_token)
+        raise CaskUnavailableError, cask_token.to_s unless cask_path.exist?
+        puts File.open(cask_path, &:read)
+      end
 
-  def self.help
-    "dump raw source of the given Cask to the standard output"
+      def self.help
+        "dump raw source of the given Cask to the standard output"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/cleanup.rb b/Library/Homebrew/cask/lib/hbc/cli/cleanup.rb
index 4115d26fc..0296dc96d 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/cleanup.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/cleanup.rb
@@ -1,108 +1,112 @@
-class Hbc::CLI::Cleanup < Hbc::CLI::Base
-  OUTDATED_DAYS = 10
-  OUTDATED_TIMESTAMP = Time.now - (60 * 60 * 24 * OUTDATED_DAYS)
-
-  def self.help
-    "cleans up cached downloads and tracker symlinks"
-  end
-
-  def self.needs_init?
-    true
-  end
+module Hbc
+  class CLI
+    class Cleanup < Base
+      OUTDATED_DAYS = 10
+      OUTDATED_TIMESTAMP = Time.now - (60 * 60 * 24 * OUTDATED_DAYS)
+
+      def self.help
+        "cleans up cached downloads and tracker symlinks"
+      end
 
-  def self.run(*args)
-    if args.empty?
-      default.cleanup!
-    else
-      default.cleanup(args)
-    end
-  end
+      def self.needs_init?
+        true
+      end
 
-  def self.default
-    @default ||= new(Hbc.cache, Hbc.cleanup_outdated)
-  end
+      def self.run(*args)
+        if args.empty?
+          default.cleanup!
+        else
+          default.cleanup(args)
+        end
+      end
 
-  attr_reader :cache_location, :outdated_only
-  def initialize(cache_location, outdated_only)
-    @cache_location = Pathname.new(cache_location)
-    @outdated_only = outdated_only
-  end
+      def self.default
+        @default ||= new(Hbc.cache, Hbc.cleanup_outdated)
+      end
 
-  def cleanup!
-    remove_cache_files
-  end
+      attr_reader :cache_location, :outdated_only
+      def initialize(cache_location, outdated_only)
+        @cache_location = Pathname.new(cache_location)
+        @outdated_only = outdated_only
+      end
 
-  def cleanup(tokens)
-    remove_cache_files(*tokens)
-  end
+      def cleanup!
+        remove_cache_files
+      end
 
-  def cache_files
-    return [] unless cache_location.exist?
-    cache_location.children
-                  .map(&method(:Pathname))
-                  .reject(&method(:outdated?))
-  end
+      def cleanup(tokens)
+        remove_cache_files(*tokens)
+      end
 
-  def outdated?(file)
-    outdated_only && file && file.stat.mtime > OUTDATED_TIMESTAMP
-  end
+      def cache_files
+        return [] unless cache_location.exist?
+        cache_location.children
+                      .map(&method(:Pathname))
+                      .reject(&method(:outdated?))
+      end
 
-  def incomplete?(file)
-    file.extname == ".incomplete"
-  end
+      def outdated?(file)
+        outdated_only && file && file.stat.mtime > OUTDATED_TIMESTAMP
+      end
 
-  def cache_incompletes
-    cache_files.select(&method(:incomplete?))
-  end
+      def incomplete?(file)
+        file.extname == ".incomplete"
+      end
 
-  def cache_completes
-    cache_files.reject(&method(:incomplete?))
-  end
+      def cache_incompletes
+        cache_files.select(&method(:incomplete?))
+      end
 
-  def disk_cleanup_size
-    Hbc::Utils.size_in_bytes(cache_files)
-  end
+      def cache_completes
+        cache_files.reject(&method(:incomplete?))
+      end
 
-  def remove_cache_files(*tokens)
-    message = "Removing cached downloads"
-    message.concat " for #{tokens.join(', ')}" unless tokens.empty?
-    message.concat " older than #{OUTDATED_DAYS} days old" if outdated_only
-    ohai message
+      def disk_cleanup_size
+        Utils.size_in_bytes(cache_files)
+      end
 
-    deletable_cache_files = if tokens.empty?
-                              cache_files
-                            else
-                              start_withs = tokens.map { |token| "#{token}--" }
+      def remove_cache_files(*tokens)
+        message = "Removing cached downloads"
+        message.concat " for #{tokens.join(", ")}" unless tokens.empty?
+        message.concat " older than #{OUTDATED_DAYS} days old" if outdated_only
+        ohai message
 
-                              cache_files.select { |path|
-                                path.basename.to_s.start_with?(*start_withs)
-                              }
-                            end
+        deletable_cache_files = if tokens.empty?
+                                  cache_files
+                                else
+                                  start_withs = tokens.map { |token| "#{token}--" }
 
-    delete_paths(deletable_cache_files)
-  end
+                                  cache_files.select { |path|
+                                    path.basename.to_s.start_with?(*start_withs)
+                                  }
+                                end
 
-  def delete_paths(paths)
-    cleanup_size = 0
-    processed_files = 0
-    paths.each do |item|
-      next unless item.exist?
-      processed_files += 1
-      if Hbc::Utils.file_locked?(item)
-        puts "skipping: #{item} is locked"
-        next
+        delete_paths(deletable_cache_files)
       end
-      puts item
-      item_size = File.size?(item)
-      cleanup_size += item_size unless item_size.nil?
-      item.unlink
-    end
 
-    if processed_files.zero?
-      puts "Nothing to do"
-    else
-      disk_space = disk_usage_readable(cleanup_size)
-      ohai "This operation has freed approximately #{disk_space} of disk space."
+      def delete_paths(paths)
+        cleanup_size = 0
+        processed_files = 0
+        paths.each do |item|
+          next unless item.exist?
+          processed_files += 1
+          if Utils.file_locked?(item)
+            puts "skipping: #{item} is locked"
+            next
+          end
+          puts item
+          item_size = File.size?(item)
+          cleanup_size += item_size unless item_size.nil?
+          item.unlink
+        end
+
+        if processed_files.zero?
+          puts "Nothing to do"
+        else
+          disk_space = disk_usage_readable(cleanup_size)
+          ohai "This operation has freed approximately #{disk_space} of disk space."
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/create.rb b/Library/Homebrew/cask/lib/hbc/cli/create.rb
index 3c1ac76ed..14860942f 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/create.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/create.rb
@@ -1,37 +1,41 @@
-class Hbc::CLI::Create < Hbc::CLI::Base
-  def self.run(*args)
-    cask_tokens = cask_tokens_from(args)
-    raise Hbc::CaskUnspecifiedError if cask_tokens.empty?
-    cask_token = cask_tokens.first.sub(%r{\.rb$}i, "")
-    cask_path = Hbc.path(cask_token)
-    odebug "Creating Cask #{cask_token}"
+module Hbc
+  class CLI
+    class Create < Base
+      def self.run(*args)
+        cask_tokens = cask_tokens_from(args)
+        raise CaskUnspecifiedError if cask_tokens.empty?
+        cask_token = cask_tokens.first.sub(%r{\.rb$}i, "")
+        cask_path = Hbc.path(cask_token)
+        odebug "Creating Cask #{cask_token}"
 
-    raise Hbc::CaskAlreadyCreatedError, cask_token if cask_path.exist?
+        raise CaskAlreadyCreatedError, cask_token if cask_path.exist?
 
-    File.open(cask_path, "w") do |f|
-      f.write template(cask_token)
-    end
+        File.open(cask_path, "w") do |f|
+          f.write template(cask_token)
+        end
 
-    exec_editor cask_path
-  end
+        exec_editor cask_path
+      end
 
-  def self.template(cask_token)
-    <<-EOS.undent
-      cask '#{cask_token}' do
-        version ''
-        sha256 ''
+      def self.template(cask_token)
+        <<-EOS.undent
+          cask '#{cask_token}' do
+            version ''
+            sha256 ''
 
-        url 'https://'
-        name ''
-        homepage ''
-        license :unknown # TODO: change license and remove this comment; ':unknown' is a machine-generated placeholder
+            url 'https://'
+            name ''
+            homepage ''
+            license :unknown # TODO: change license and remove this comment; ':unknown' is a machine-generated placeholder
 
-        app ''
+            app ''
+          end
+        EOS
       end
-    EOS
-  end
 
-  def self.help
-    "creates the given Cask and opens it in an editor"
+      def self.help
+        "creates the given Cask and opens it in an editor"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/doctor.rb b/Library/Homebrew/cask/lib/hbc/cli/doctor.rb
index 2632bcaef..34f000b29 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/doctor.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/doctor.rb
@@ -1,205 +1,209 @@
-class Hbc::CLI::Doctor < Hbc::CLI::Base
-  def self.run
-    ohai "macOS Release:", render_with_none_as_error(MacOS.full_version)
-    ohai "Hardware Architecture:", render_with_none_as_error("#{Hardware::CPU.type}-#{Hardware::CPU.bits}")
-    ohai "Ruby Version:", render_with_none_as_error("#{RUBY_VERSION}-p#{RUBY_PATCHLEVEL}")
-    ohai "Ruby Path:", render_with_none_as_error(RbConfig.ruby)
-    # TODO: consider removing most Homebrew constants from doctor output
-    ohai "Homebrew Version:", render_with_none_as_error(homebrew_version)
-    ohai "Homebrew Executable Path:", render_with_none_as_error(Hbc.homebrew_executable)
-    ohai "Homebrew Cellar Path:", render_with_none_as_error(homebrew_cellar)
-    ohai "Homebrew Repository Path:", render_with_none_as_error(homebrew_repository)
-    ohai "Homebrew Origin:", render_with_none_as_error(homebrew_origin)
-    ohai "Homebrew-Cask Version:", render_with_none_as_error(Hbc.full_version)
-    ohai "Homebrew-Cask Install Location:", render_install_location
-    ohai "Homebrew-Cask Staging Location:", render_staging_location(Hbc.caskroom)
-    ohai "Homebrew-Cask Cached Downloads:", render_cached_downloads
-    ohai "Homebrew-Cask Default Tap Path:", render_tap_paths(Hbc.default_tap.path)
-    ohai "Homebrew-Cask Alternate Cask Taps:", render_tap_paths(alt_taps)
-    ohai "Homebrew-Cask Default Tap Cask Count:", render_with_none_as_error(default_cask_count)
-    ohai "Contents of $LOAD_PATH:", render_load_path($LOAD_PATH)
-    ohai "Contents of $RUBYLIB Environment Variable:", render_env_var("RUBYLIB")
-    ohai "Contents of $RUBYOPT Environment Variable:", render_env_var("RUBYOPT")
-    ohai "Contents of $RUBYPATH Environment Variable:", render_env_var("RUBYPATH")
-    ohai "Contents of $RBENV_VERSION Environment Variable:", render_env_var("RBENV_VERSION")
-    ohai "Contents of $CHRUBY_VERSION Environment Variable:", render_env_var("CHRUBY_VERSION")
-    ohai "Contents of $GEM_HOME Environment Variable:", render_env_var("GEM_HOME")
-    ohai "Contents of $GEM_PATH Environment Variable:", render_env_var("GEM_PATH")
-    ohai "Contents of $BUNDLE_PATH Environment Variable:", render_env_var("BUNDLE_PATH")
-    ohai "Contents of $PATH Environment Variable:", render_env_var("PATH")
-    ohai "Contents of $SHELL Environment Variable:", render_env_var("SHELL")
-    ohai "Contents of Locale Environment Variables:", render_with_none(locale_variables)
-    ohai "Running As Privileged User:", render_with_none_as_error(privileged_uid)
-  end
+module Hbc
+  class CLI
+    class Doctor < Base
+      def self.run
+        ohai "macOS Release:", render_with_none_as_error(MacOS.full_version)
+        ohai "Hardware Architecture:", render_with_none_as_error("#{Hardware::CPU.type}-#{Hardware::CPU.bits}")
+        ohai "Ruby Version:", render_with_none_as_error("#{RUBY_VERSION}-p#{RUBY_PATCHLEVEL}")
+        ohai "Ruby Path:", render_with_none_as_error(RbConfig.ruby)
+        # TODO: consider removing most Homebrew constants from doctor output
+        ohai "Homebrew Version:", render_with_none_as_error(homebrew_version)
+        ohai "Homebrew Executable Path:", render_with_none_as_error(Hbc.homebrew_executable)
+        ohai "Homebrew Cellar Path:", render_with_none_as_error(homebrew_cellar)
+        ohai "Homebrew Repository Path:", render_with_none_as_error(homebrew_repository)
+        ohai "Homebrew Origin:", render_with_none_as_error(homebrew_origin)
+        ohai "Homebrew-Cask Version:", render_with_none_as_error(Hbc.full_version)
+        ohai "Homebrew-Cask Install Location:", render_install_location
+        ohai "Homebrew-Cask Staging Location:", render_staging_location(Hbc.caskroom)
+        ohai "Homebrew-Cask Cached Downloads:", render_cached_downloads
+        ohai "Homebrew-Cask Default Tap Path:", render_tap_paths(Hbc.default_tap.path)
+        ohai "Homebrew-Cask Alternate Cask Taps:", render_tap_paths(alt_taps)
+        ohai "Homebrew-Cask Default Tap Cask Count:", render_with_none_as_error(default_cask_count)
+        ohai "Contents of $LOAD_PATH:", render_load_path($LOAD_PATH)
+        ohai "Contents of $RUBYLIB Environment Variable:", render_env_var("RUBYLIB")
+        ohai "Contents of $RUBYOPT Environment Variable:", render_env_var("RUBYOPT")
+        ohai "Contents of $RUBYPATH Environment Variable:", render_env_var("RUBYPATH")
+        ohai "Contents of $RBENV_VERSION Environment Variable:", render_env_var("RBENV_VERSION")
+        ohai "Contents of $CHRUBY_VERSION Environment Variable:", render_env_var("CHRUBY_VERSION")
+        ohai "Contents of $GEM_HOME Environment Variable:", render_env_var("GEM_HOME")
+        ohai "Contents of $GEM_PATH Environment Variable:", render_env_var("GEM_PATH")
+        ohai "Contents of $BUNDLE_PATH Environment Variable:", render_env_var("BUNDLE_PATH")
+        ohai "Contents of $PATH Environment Variable:", render_env_var("PATH")
+        ohai "Contents of $SHELL Environment Variable:", render_env_var("SHELL")
+        ohai "Contents of Locale Environment Variables:", render_with_none(locale_variables)
+        ohai "Running As Privileged User:", render_with_none_as_error(privileged_uid)
+      end
 
-  def self.alt_taps
-    Tap.select { |t| t.cask_dir && t != Hbc.default_tap }
-       .map(&:path)
-  end
+      def self.alt_taps
+        Tap.select { |t| t.cask_dir && t != Hbc.default_tap }
+           .map(&:path)
+      end
 
-  def self.default_cask_count
-    Hbc.default_tap.cask_files.count
-  rescue StandardError
-    "0 #{error_string "Error reading #{Hbc.default_tap.path}"}"
-  end
+      def self.default_cask_count
+        Hbc.default_tap.cask_files.count
+      rescue StandardError
+        "0 #{error_string "Error reading #{Hbc.default_tap.path}"}"
+      end
 
-  def self.homebrew_origin
-    homebrew_origin = notfound_string
-    begin
-      Dir.chdir(homebrew_repository) do
-        homebrew_origin = Hbc::SystemCommand.run("/usr/bin/git",
-                                                 args:         %w[config --get remote.origin.url],
-                                                 print_stderr: false).stdout.strip
-      end
-      if homebrew_origin !~ %r{\S}
-        homebrew_origin = "#{none_string} #{error_string}"
-      elsif homebrew_origin !~ %r{(mxcl|Homebrew)/(home)?brew(\.git)?\Z}
-        homebrew_origin.concat " #{error_string 'warning: nonstandard origin'}"
-      end
-    rescue StandardError
-      homebrew_origin = error_string "Not Found - Error running git"
-    end
-    homebrew_origin
-  end
+      def self.homebrew_origin
+        homebrew_origin = notfound_string
+        begin
+          Dir.chdir(homebrew_repository) do
+            homebrew_origin = SystemCommand.run("/usr/bin/git",
+                                                     args:         %w[config --get remote.origin.url],
+                                                     print_stderr: false).stdout.strip
+          end
+          if homebrew_origin !~ %r{\S}
+            homebrew_origin = "#{none_string} #{error_string}"
+          elsif homebrew_origin !~ %r{(mxcl|Homebrew)/(home)?brew(\.git)?\Z}
+            homebrew_origin.concat " #{error_string "warning: nonstandard origin"}"
+          end
+        rescue StandardError
+          homebrew_origin = error_string "Not Found - Error running git"
+        end
+        homebrew_origin
+      end
 
-  def self.homebrew_repository
-    homebrew_constants("repository")
-  end
+      def self.homebrew_repository
+        homebrew_constants("repository")
+      end
 
-  def self.homebrew_cellar
-    homebrew_constants("cellar")
-  end
+      def self.homebrew_cellar
+        homebrew_constants("cellar")
+      end
 
-  def self.homebrew_version
-    homebrew_constants("version")
-  end
+      def self.homebrew_version
+        homebrew_constants("version")
+      end
 
-  def self.homebrew_taps
-    @homebrew_taps ||= if homebrew_repository.respond_to?(:join)
-                         homebrew_repository.join("Library", "Taps")
-                       end
-  end
+      def self.homebrew_taps
+        @homebrew_taps ||= if homebrew_repository.respond_to?(:join)
+                             homebrew_repository.join("Library", "Taps")
+                           end
+      end
 
-  def self.homebrew_constants(name)
-    @homebrew_constants ||= {}
-    return @homebrew_constants[name] if @homebrew_constants.key?(name)
-    @homebrew_constants[name] = notfound_string
-    begin
-      @homebrew_constants[name] = Hbc::SystemCommand.run!(Hbc.homebrew_executable,
-                                                          args:         ["--#{name}"],
-                                                          print_stderr: false)
-                                                    .stdout
-                                                    .strip
-      if @homebrew_constants[name] !~ %r{\S}
-        @homebrew_constants[name] = "#{none_string} #{error_string}"
-      end
-      path = Pathname.new(@homebrew_constants[name])
-      @homebrew_constants[name] = path if path.exist?
-    rescue StandardError
-      @homebrew_constants[name] = error_string "Not Found - Error running brew"
-    end
-    @homebrew_constants[name]
-  end
+      def self.homebrew_constants(name)
+        @homebrew_constants ||= {}
+        return @homebrew_constants[name] if @homebrew_constants.key?(name)
+        @homebrew_constants[name] = notfound_string
+        begin
+          @homebrew_constants[name] = SystemCommand.run!(Hbc.homebrew_executable,
+                                                              args:         ["--#{name}"],
+                                                              print_stderr: false)
+                                                        .stdout
+                                                        .strip
+          if @homebrew_constants[name] !~ %r{\S}
+            @homebrew_constants[name] = "#{none_string} #{error_string}"
+          end
+          path = Pathname.new(@homebrew_constants[name])
+          @homebrew_constants[name] = path if path.exist?
+        rescue StandardError
+          @homebrew_constants[name] = error_string "Not Found - Error running brew"
+        end
+        @homebrew_constants[name]
+      end
 
-  def self.locale_variables
-    ENV.keys.grep(%r{^(?:LC_\S+|LANG|LANGUAGE)\Z}).collect { |v| %Q{#{v}="#{ENV[v]}"} }.sort.join("\n")
-  end
+      def self.locale_variables
+        ENV.keys.grep(%r{^(?:LC_\S+|LANG|LANGUAGE)\Z}).collect { |v| %Q{#{v}="#{ENV[v]}"} }.sort.join("\n")
+      end
 
-  def self.privileged_uid
-    Process.euid == 0 ? "Yes #{error_string 'warning: not recommended'}" : "No"
-  rescue StandardError
-    notfound_string
-  end
+      def self.privileged_uid
+        Process.euid.zero? ? "Yes #{error_string "warning: not recommended"}" : "No"
+      rescue StandardError
+        notfound_string
+      end
 
-  def self.none_string
-    "<NONE>"
-  end
+      def self.none_string
+        "<NONE>"
+      end
 
-  def self.legacy_tap_pattern
-    %r{phinze}
-  end
+      def self.legacy_tap_pattern
+        %r{phinze}
+      end
 
-  def self.notfound_string
-    "#{Tty.red}Not Found - Unknown Error#{Tty.reset}"
-  end
+      def self.notfound_string
+        "#{Tty.red}Not Found - Unknown Error#{Tty.reset}"
+      end
 
-  def self.error_string(string = "Error")
-    "#{Tty.red}(#{string})#{Tty.reset}"
-  end
+      def self.error_string(string = "Error")
+        "#{Tty.red}(#{string})#{Tty.reset}"
+      end
 
-  def self.render_with_none(string)
-    return string if !string.nil? && string.respond_to?(:to_s) && !string.to_s.empty?
-    none_string
-  end
+      def self.render_with_none(string)
+        return string if !string.nil? && string.respond_to?(:to_s) && !string.to_s.empty?
+        none_string
+      end
 
-  def self.render_with_none_as_error(string)
-    return string if !string.nil? && string.respond_to?(:to_s) && !string.to_s.empty?
-    "#{none_string} #{error_string}"
-  end
+      def self.render_with_none_as_error(string)
+        return string if !string.nil? && string.respond_to?(:to_s) && !string.to_s.empty?
+        "#{none_string} #{error_string}"
+      end
 
-  def self.render_tap_paths(paths)
-    paths = [paths] unless paths.respond_to?(:each)
-    paths.collect do |dir|
-      if dir.nil? || dir.to_s.empty?
-        none_string
-      elsif dir.to_s.match(legacy_tap_pattern)
-        dir.to_s.concat(" #{error_string 'Warning: legacy tap path'}")
-      else
-        dir.to_s
+      def self.render_tap_paths(paths)
+        paths = [paths] unless paths.respond_to?(:each)
+        paths.collect do |dir|
+          if dir.nil? || dir.to_s.empty?
+            none_string
+          elsif dir.to_s.match(legacy_tap_pattern)
+            dir.to_s.concat(" #{error_string "Warning: legacy tap path"}")
+          else
+            dir.to_s
+          end
+        end
       end
-    end
-  end
 
-  def self.render_env_var(var)
-    if ENV.key?(var)
-      %Q{#{var}="#{ENV[var]}"}
-    else
-      none_string
-    end
-  end
+      def self.render_env_var(var)
+        if ENV.key?(var)
+          %Q{#{var}="#{ENV[var]}"}
+        else
+          none_string
+        end
+      end
 
-  # This could be done by calling into Homebrew, but the situation
-  # where "doctor" is needed is precisely the situation where such
-  # things are less dependable.
-  def self.render_install_location
-    locations = Dir.glob(Pathname.new(homebrew_cellar).join("brew-cask", "*")).reverse
-    if locations.empty?
-      none_string
-    else
-      locations.collect do |l|
-        "#{l} #{error_string 'error: legacy install. Run "brew uninstall --force brew-cask".'}"
+      # This could be done by calling into Homebrew, but the situation
+      # where "doctor" is needed is precisely the situation where such
+      # things are less dependable.
+      def self.render_install_location
+        locations = Dir.glob(Pathname.new(homebrew_cellar).join("brew-cask", "*")).reverse
+        if locations.empty?
+          none_string
+        else
+          locations.collect do |l|
+            "#{l} #{error_string 'error: legacy install. Run "brew uninstall --force brew-cask".'}"
+          end
+        end
       end
-    end
-  end
 
-  def self.render_staging_location(path)
-    path = Pathname.new(path)
-    if !path.exist?
-      "#{path} #{error_string 'error: path does not exist'}}"
-    elsif !path.writable?
-      "#{path} #{error_string 'error: not writable by current user'}"
-    else
-      path
-    end
-  end
+      def self.render_staging_location(path)
+        path = Pathname.new(path)
+        if !path.exist?
+          "#{path} #{error_string "error: path does not exist"}}"
+        elsif !path.writable?
+          "#{path} #{error_string "error: not writable by current user"}"
+        else
+          path
+        end
+      end
 
-  def self.render_load_path(paths)
-    return "#{none_string} #{error_string}" if [*paths].empty?
-    paths
-  end
+      def self.render_load_path(paths)
+        return "#{none_string} #{error_string}" if [*paths].empty?
+        paths
+      end
 
-  def self.render_cached_downloads
-    cleanup = Hbc::CLI::Cleanup.default
-    files = cleanup.cache_files
-    count = files.count
-    size = cleanup.disk_cleanup_size
-    size_msg = "#{number_readable(count)} files, #{disk_usage_readable(size)}"
-    warn_msg = error_string('warning: run "brew cask cleanup"')
-    size_msg << " #{warn_msg}" if count > 0
-    [Hbc.cache, size_msg]
-  end
+      def self.render_cached_downloads
+        cleanup = CLI::Cleanup.default
+        files = cleanup.cache_files
+        count = files.count
+        size = cleanup.disk_cleanup_size
+        size_msg = "#{number_readable(count)} files, #{disk_usage_readable(size)}"
+        warn_msg = error_string('warning: run "brew cask cleanup"')
+        size_msg << " #{warn_msg}" if count > 0
+        [Hbc.cache, size_msg]
+      end
 
-  def self.help
-    "checks for configuration issues"
+      def self.help
+        "checks for configuration issues"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/edit.rb b/Library/Homebrew/cask/lib/hbc/cli/edit.rb
index b2d4a9156..3090cf196 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/edit.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/edit.rb
@@ -1,18 +1,22 @@
-class Hbc::CLI::Edit < Hbc::CLI::Base
-  def self.run(*args)
-    cask_tokens = cask_tokens_from(args)
-    raise Hbc::CaskUnspecifiedError if cask_tokens.empty?
-    # only respects the first argument
-    cask_token = cask_tokens.first.sub(%r{\.rb$}i, "")
-    cask_path = Hbc.path(cask_token)
-    odebug "Opening editor for Cask #{cask_token}"
-    unless cask_path.exist?
-      raise Hbc::CaskUnavailableError, %Q{#{cask_token}, run "brew cask create #{cask_token}" to create a new Cask}
-    end
-    exec_editor cask_path
-  end
+module Hbc
+  class CLI
+    class Edit < Base
+      def self.run(*args)
+        cask_tokens = cask_tokens_from(args)
+        raise CaskUnspecifiedError if cask_tokens.empty?
+        # only respects the first argument
+        cask_token = cask_tokens.first.sub(%r{\.rb$}i, "")
+        cask_path = Hbc.path(cask_token)
+        odebug "Opening editor for Cask #{cask_token}"
+        unless cask_path.exist?
+          raise CaskUnavailableError, %Q{#{cask_token}, run "brew cask create #{cask_token}" to create a new Cask}
+        end
+        exec_editor cask_path
+      end
 
-  def self.help
-    "edits the given Cask"
+      def self.help
+        "edits the given Cask"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/fetch.rb b/Library/Homebrew/cask/lib/hbc/cli/fetch.rb
index 647f2af2c..9b3d5099c 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/fetch.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/fetch.rb
@@ -1,19 +1,23 @@
-class Hbc::CLI::Fetch < Hbc::CLI::Base
-  def self.run(*args)
-    cask_tokens = cask_tokens_from(args)
-    raise Hbc::CaskUnspecifiedError if cask_tokens.empty?
-    force = args.include? "--force"
+module Hbc
+  class CLI
+    class Fetch < Base
+      def self.run(*args)
+        cask_tokens = cask_tokens_from(args)
+        raise CaskUnspecifiedError if cask_tokens.empty?
+        force = args.include? "--force"
 
-    cask_tokens.each do |cask_token|
-      ohai "Downloading external files for Cask #{cask_token}"
-      cask = Hbc.load(cask_token)
-      downloaded_path = Hbc::Download.new(cask, force: force).perform
-      Hbc::Verify.all(cask, downloaded_path)
-      ohai "Success! Downloaded to -> #{downloaded_path}"
-    end
-  end
+        cask_tokens.each do |cask_token|
+          ohai "Downloading external files for Cask #{cask_token}"
+          cask = Hbc.load(cask_token)
+          downloaded_path = Download.new(cask, force: force).perform
+          Verify.all(cask, downloaded_path)
+          ohai "Success! Downloaded to -> #{downloaded_path}"
+        end
+      end
 
-  def self.help
-    "downloads remote application files to local cache"
+      def self.help
+        "downloads remote application files to local cache"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/home.rb b/Library/Homebrew/cask/lib/hbc/cli/home.rb
index 9c8c0a0e4..b35b08279 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/home.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/home.rb
@@ -1,18 +1,22 @@
-class Hbc::CLI::Home < Hbc::CLI::Base
-  def self.run(*cask_tokens)
-    if cask_tokens.empty?
-      odebug "Opening project homepage"
-      system "/usr/bin/open", "--", "http://caskroom.io/"
-    else
-      cask_tokens.each do |cask_token|
-        odebug "Opening homepage for Cask #{cask_token}"
-        cask = Hbc.load(cask_token)
-        system "/usr/bin/open", "--", cask.homepage
+module Hbc
+  class CLI
+    class Home < Base
+      def self.run(*cask_tokens)
+        if cask_tokens.empty?
+          odebug "Opening project homepage"
+          system "/usr/bin/open", "--", "http://caskroom.io/"
+        else
+          cask_tokens.each do |cask_token|
+            odebug "Opening homepage for Cask #{cask_token}"
+            cask = Hbc.load(cask_token)
+            system "/usr/bin/open", "--", cask.homepage
+          end
+        end
       end
-    end
-  end
 
-  def self.help
-    "opens the homepage of the given Cask"
+      def self.help
+        "opens the homepage of the given Cask"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/info.rb b/Library/Homebrew/cask/lib/hbc/cli/info.rb
index 76f2d1366..7fbdff3eb 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/info.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/info.rb
@@ -1,65 +1,69 @@
-class Hbc::CLI::Info < Hbc::CLI::Base
-  def self.run(*args)
-    cask_tokens = cask_tokens_from(args)
-    raise Hbc::CaskUnspecifiedError if cask_tokens.empty?
-    cask_tokens.each do |cask_token|
-      odebug "Getting info for Cask #{cask_token}"
-      cask = Hbc.load(cask_token)
+module Hbc
+  class CLI
+    class Info < Base
+      def self.run(*args)
+        cask_tokens = cask_tokens_from(args)
+        raise CaskUnspecifiedError if cask_tokens.empty?
+        cask_tokens.each do |cask_token|
+          odebug "Getting info for Cask #{cask_token}"
+          cask = Hbc.load(cask_token)
 
-      info(cask)
-    end
-  end
+          info(cask)
+        end
+      end
 
-  def self.help
-    "displays information about the given Cask"
-  end
+      def self.help
+        "displays information about the given Cask"
+      end
 
-  def self.info(cask)
-    puts "#{cask.token}: #{cask.version}"
-    puts formatted_url(cask.homepage) if cask.homepage
-    installation_info(cask)
-    puts "From: #{formatted_url(github_info(cask))}" if github_info(cask)
-    name_info(cask)
-    artifact_info(cask)
-    Hbc::Installer.print_caveats(cask)
-  end
+      def self.info(cask)
+        puts "#{cask.token}: #{cask.version}"
+        puts formatted_url(cask.homepage) if cask.homepage
+        installation_info(cask)
+        puts "From: #{formatted_url(github_info(cask))}" if github_info(cask)
+        name_info(cask)
+        artifact_info(cask)
+        Installer.print_caveats(cask)
+      end
 
-  def self.formatted_url(url)
-    "#{Tty.em}#{url}#{Tty.reset}"
-  end
+      def self.formatted_url(url)
+        "#{Tty.em}#{url}#{Tty.reset}"
+      end
 
-  def self.installation_info(cask)
-    if cask.installed?
-      cask.versions.each do |version|
-        versioned_staged_path = cask.caskroom_path.join(version)
+      def self.installation_info(cask)
+        if cask.installed?
+          cask.versions.each do |version|
+            versioned_staged_path = cask.caskroom_path.join(version)
 
-        puts versioned_staged_path.to_s
-          .concat(" (")
-          .concat(versioned_staged_path.exist? ? versioned_staged_path.abv : "#{Tty.red}does not exist#{Tty.reset}")
-          .concat(")")
+            puts versioned_staged_path.to_s
+              .concat(" (")
+              .concat(versioned_staged_path.exist? ? versioned_staged_path.abv : "#{Tty.red}does not exist#{Tty.reset}")
+              .concat(")")
+          end
+        else
+          puts "Not installed"
+        end
       end
-    else
-      puts "Not installed"
-    end
-  end
 
-  def self.name_info(cask)
-    ohai cask.name.size > 1 ? "Names" : "Name"
-    puts cask.name.empty? ? "#{Tty.red}None#{Tty.reset}" : cask.name
-  end
+      def self.name_info(cask)
+        ohai cask.name.size > 1 ? "Names" : "Name"
+        puts cask.name.empty? ? "#{Tty.red}None#{Tty.reset}" : cask.name
+      end
 
-  def self.github_info(cask)
-    user, repo, token = Hbc::QualifiedToken.parse(Hbc.all_tokens.detect { |t| t.split("/").last == cask.token })
-    "#{Tap.fetch(user, repo).default_remote}/blob/master/Casks/#{token}.rb"
-  end
+      def self.github_info(cask)
+        user, repo, token = QualifiedToken.parse(Hbc.all_tokens.detect { |t| t.split("/").last == cask.token })
+        "#{Tap.fetch(user, repo).default_remote}/blob/master/Casks/#{token}.rb"
+      end
 
-  def self.artifact_info(cask)
-    ohai "Artifacts"
-    Hbc::DSL::ORDINARY_ARTIFACT_TYPES.each do |type|
-      next if cask.artifacts[type].empty?
-      cask.artifacts[type].each do |artifact|
-        activatable_item = type == :stage_only ? "<none>" : artifact.first
-        puts "#{activatable_item} (#{type})"
+      def self.artifact_info(cask)
+        ohai "Artifacts"
+        DSL::ORDINARY_ARTIFACT_TYPES.each do |type|
+          next if cask.artifacts[type].empty?
+          cask.artifacts[type].each do |artifact|
+            activatable_item = type == :stage_only ? "<none>" : artifact.first
+            puts "#{activatable_item} (#{type})"
+          end
+        end
       end
     end
   end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/install.rb b/Library/Homebrew/cask/lib/hbc/cli/install.rb
index 43eab9f3d..d7575344d 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/install.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/install.rb
@@ -1,60 +1,63 @@
+module Hbc
+  class CLI
+    class Install < Base
+      def self.run(*args)
+        cask_tokens = cask_tokens_from(args)
+        raise CaskUnspecifiedError if cask_tokens.empty?
+        force = args.include? "--force"
+        skip_cask_deps = args.include? "--skip-cask-deps"
+        require_sha = args.include? "--require-sha"
+        retval = install_casks cask_tokens, force, skip_cask_deps, require_sha
+        # retval is ternary: true/false/nil
 
-class Hbc::CLI::Install < Hbc::CLI::Base
-  def self.run(*args)
-    cask_tokens = cask_tokens_from(args)
-    raise Hbc::CaskUnspecifiedError if cask_tokens.empty?
-    force = args.include? "--force"
-    skip_cask_deps = args.include? "--skip-cask-deps"
-    require_sha = args.include? "--require-sha"
-    retval = install_casks cask_tokens, force, skip_cask_deps, require_sha
-    # retval is ternary: true/false/nil
-
-    raise Hbc::CaskError, "nothing to install" if retval.nil?
-    raise Hbc::CaskError, "install incomplete" unless retval
-  end
+        raise CaskError, "nothing to install" if retval.nil?
+        raise CaskError, "install incomplete" unless retval
+      end
 
-  def self.install_casks(cask_tokens, force, skip_cask_deps, require_sha)
-    count = 0
-    cask_tokens.each do |cask_token|
-      begin
-        cask = Hbc.load(cask_token)
-        Hbc::Installer.new(cask,
-                           force:          force,
-                           skip_cask_deps: skip_cask_deps,
-                           require_sha:    require_sha).install
-        count += 1
-      rescue Hbc::CaskAlreadyInstalledError => e
-        opoo e.message
-        count += 1
-      rescue Hbc::CaskAutoUpdatesError => e
-        opoo e.message
-        count += 1
-      rescue Hbc::CaskUnavailableError => e
-        warn_unavailable_with_suggestion cask_token, e
-      rescue Hbc::CaskNoShasumError => e
-        opoo e.message
-        count += 1
+      def self.install_casks(cask_tokens, force, skip_cask_deps, require_sha)
+        count = 0
+        cask_tokens.each do |cask_token|
+          begin
+            cask = Hbc.load(cask_token)
+            Installer.new(cask,
+                               force:          force,
+                               skip_cask_deps: skip_cask_deps,
+                               require_sha:    require_sha).install
+            count += 1
+          rescue CaskAlreadyInstalledError => e
+            opoo e.message
+            count += 1
+          rescue CaskAutoUpdatesError => e
+            opoo e.message
+            count += 1
+          rescue CaskUnavailableError => e
+            warn_unavailable_with_suggestion cask_token, e
+          rescue CaskNoShasumError => e
+            opoo e.message
+            count += 1
+          end
+        end
+        count.zero? ? nil : count == cask_tokens.length
       end
-    end
-    count == 0 ? nil : count == cask_tokens.length
-  end
 
-  def self.warn_unavailable_with_suggestion(cask_token, e)
-    exact_match, partial_matches = Hbc::CLI::Search.search(cask_token)
-    errmsg = e.message
-    if exact_match
-      errmsg.concat(". Did you mean:\n#{exact_match}")
-    elsif !partial_matches.empty?
-      errmsg.concat(". Did you mean one of:\n#{puts_columns(partial_matches.take(20))}\n")
-    end
-    onoe errmsg
-  end
+      def self.warn_unavailable_with_suggestion(cask_token, e)
+        exact_match, partial_matches = Search.search(cask_token)
+        errmsg = e.message
+        if exact_match
+          errmsg.concat(". Did you mean:\n#{exact_match}")
+        elsif !partial_matches.empty?
+          errmsg.concat(". Did you mean one of:\n#{puts_columns(partial_matches.take(20))}\n")
+        end
+        onoe errmsg
+      end
 
-  def self.help
-    "installs the given Cask"
-  end
+      def self.help
+        "installs the given Cask"
+      end
 
-  def self.needs_init?
-    true
+      def self.needs_init?
+        true
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/internal_audit_modified_casks.rb b/Library/Homebrew/cask/lib/hbc/cli/internal_audit_modified_casks.rb
index f05dbe803..47258a7b2 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/internal_audit_modified_casks.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/internal_audit_modified_casks.rb
@@ -1,135 +1,139 @@
-class Hbc::CLI::InternalAuditModifiedCasks < Hbc::CLI::InternalUseBase
-  RELEVANT_STANZAS = %i{version sha256 url appcast}.freeze
+module Hbc
+  class CLI
+    class InternalAuditModifiedCasks < InternalUseBase
+      RELEVANT_STANZAS = %i{version sha256 url appcast}.freeze
+
+      class << self
+        def needs_init?
+          true
+        end
+
+        def run(*args)
+          commit_range = commit_range(args)
+          cleanup = args.any? { |a| a =~ %r{^-+c(leanup)?$}i }
+          new(commit_range, cleanup: cleanup).run
+        end
+
+        def commit_range(args)
+          posargs = args.reject { |a| a.empty? || a.chars.first == "-" }
+          odie usage unless posargs.size == 1
+          posargs.first
+        end
+
+        def posargs(args)
+          args.reject { |a| a.empty? || a.chars.first == "-" }
+        end
+
+        def usage
+          <<-EOS.undent
+            Usage: brew cask _audit_modified_casks [options...] <commit range>
+
+            Given a range of Git commits, find any Casks that were modified and run `brew
+            cask audit' on them. If the `url', `version', or `sha256' stanzas were modified,
+            run with the `--download' flag to verify the hash.
+
+            Options:
+              -c, --cleanup
+                Remove all cached downloads. Use with care.
+          EOS
+        end
+      end
 
-  class << self
-    def needs_init?
-      true
-    end
+      def initialize(commit_range, cleanup: false)
+        @commit_range = commit_range
+        @cleanup = cleanup
+      end
 
-    def run(*args)
-      commit_range = commit_range(args)
-      cleanup = args.any? { |a| a =~ %r{^-+c(leanup)?$}i }
-      new(commit_range, cleanup: cleanup).run
-    end
+      attr_reader :commit_range
 
-    def commit_range(args)
-      posargs = args.reject { |a| a.empty? || a.chars.first == "-" }
-      odie usage unless posargs.size == 1
-      posargs.first
-    end
+      def cleanup?
+        @cleanup
+      end
 
-    def posargs(args)
-      args.reject { |a| a.empty? || a.chars.first == "-" }
-    end
+      def run
+        at_exit do
+          cleanup
+        end
+
+        Dir.chdir git_root do
+          modified_cask_files.zip(modified_casks).each do |cask_file, cask|
+            audit(cask, cask_file)
+          end
+        end
+        report_failures
+      end
 
-    def usage
-      <<-EOS.undent
-        Usage: brew cask _audit_modified_casks [options...] <commit range>
+      def git_root
+        @git_root ||= git("rev-parse", "--show-toplevel")
+      end
 
-        Given a range of Git commits, find any Casks that were modified and run `brew
-        cask audit' on them. If the `url', `version', or `sha256' stanzas were modified,
-        run with the `--download' flag to verify the hash.
+      def modified_cask_files
+        @modified_cask_files ||= git_filter_cask_files("AM")
+      end
 
-        Options:
-          -c, --cleanup
-            Remove all cached downloads. Use with care.
-      EOS
-    end
-  end
+      def added_cask_files
+        @added_cask_files ||= git_filter_cask_files("A")
+      end
 
-  def initialize(commit_range, cleanup: false)
-    @commit_range = commit_range
-    @cleanup = cleanup
-  end
+      def git_filter_cask_files(filter)
+        git("diff", "--name-only", "--diff-filter=#{filter}", commit_range,
+            "--", Pathname.new(git_root).join("Casks", "*.rb").to_s).split("\n")
+      end
 
-  attr_reader :commit_range
+      def modified_casks
+        return @modified_casks if defined? @modified_casks
+        @modified_casks = modified_cask_files.map { |f| Hbc.load(f) }
+        if @modified_casks.any?
+          num_modified = @modified_casks.size
+          ohai "#{num_modified} modified #{pluralize("cask", num_modified)}: " \
+            "#{@modified_casks.join(" ")}"
+        end
+        @modified_casks
+      end
 
-  def cleanup?
-    @cleanup
-  end
+      def audit(cask, cask_file)
+        audit_download = audit_download?(cask, cask_file)
+        check_token_conflicts = added_cask_files.include?(cask_file)
+        success = Auditor.audit(cask, audit_download:        audit_download,
+                                      check_token_conflicts: check_token_conflicts)
+        failed_casks << cask unless success
+      end
 
-  def run
-    at_exit do
-      cleanup
-    end
+      def failed_casks
+        @failed_casks ||= []
+      end
 
-    Dir.chdir git_root do
-      modified_cask_files.zip(modified_casks).each do |cask_file, cask|
-        audit(cask, cask_file)
+      def audit_download?(cask, cask_file)
+        cask.sha256 != :no_check && relevant_stanza_modified?(cask_file)
       end
-    end
-    report_failures
-  end
 
-  def git_root
-    @git_root ||= git(*%w[rev-parse --show-toplevel])
-  end
+      def relevant_stanza_modified?(cask_file)
+        out = git("diff", commit_range, "--", cask_file)
+        out =~ %r{^\+\s*(#{RELEVANT_STANZAS.join('|')})}
+      end
 
-  def modified_cask_files
-    @modified_cask_files ||= git_filter_cask_files("AM")
-  end
+      def git(*args)
+        odebug ["git", *args].join(" ")
+        out, err, status = Open3.capture3("git", *args)
+        return out.chomp if status.success?
+        odie err.chomp
+      end
 
-  def added_cask_files
-    @added_cask_files ||= git_filter_cask_files("A")
-  end
+      def report_failures
+        return if failed_casks.empty?
+        num_failed = failed_casks.size
+        cask_pluralized = pluralize("cask", num_failed)
+        odie "audit failed for #{num_failed} #{cask_pluralized}: " \
+          "#{failed_casks.join(" ")}"
+      end
 
-  def git_filter_cask_files(filter)
-    git("diff", "--name-only", "--diff-filter=#{filter}", commit_range,
-        "--", Pathname.new(git_root).join("Casks", "*.rb").to_s).split("\n")
-  end
+      def pluralize(str, num)
+        num == 1 ?  str : "#{str}s"
+      end
 
-  def modified_casks
-    return @modified_casks if defined? @modified_casks
-    @modified_casks = modified_cask_files.map { |f| Hbc.load(f) }
-    if @modified_casks.any?
-      num_modified = @modified_casks.size
-      ohai "#{num_modified} modified #{pluralize('cask', num_modified)}: " \
-        "#{@modified_casks.join(' ')}"
+      def cleanup
+        Cleanup.run if cleanup?
+      end
     end
-    @modified_casks
-  end
-
-  def audit(cask, cask_file)
-    audit_download = audit_download?(cask, cask_file)
-    check_token_conflicts = added_cask_files.include?(cask_file)
-    success = Hbc::Auditor.audit(cask, audit_download:        audit_download,
-                                       check_token_conflicts: check_token_conflicts)
-    failed_casks << cask unless success
-  end
-
-  def failed_casks
-    @failed_casks ||= []
-  end
-
-  def audit_download?(cask, cask_file)
-    cask.sha256 != :no_check && relevant_stanza_modified?(cask_file)
-  end
-
-  def relevant_stanza_modified?(cask_file)
-    out = git("diff", commit_range, "--", cask_file)
-    out =~ %r{^\+\s*(#{RELEVANT_STANZAS.join('|')})}
-  end
-
-  def git(*args)
-    odebug ["git", *args].join(" ")
-    out, err, status = Open3.capture3("git", *args)
-    return out.chomp if status.success?
-    odie err.chomp
-  end
-
-  def report_failures
-    return if failed_casks.empty?
-    num_failed = failed_casks.size
-    cask_pluralized = pluralize("cask", num_failed)
-    odie "audit failed for #{num_failed} #{cask_pluralized}: " \
-      "#{failed_casks.join(' ')}"
-  end
-
-  def pluralize(str, num)
-    num == 1 ?  str : "#{str}s"
-  end
-
-  def cleanup
-    Hbc::CLI::Cleanup.run if cleanup?
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/internal_checkurl.rb b/Library/Homebrew/cask/lib/hbc/cli/internal_checkurl.rb
index d53f420e2..77cf250b1 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/internal_checkurl.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/internal_checkurl.rb
@@ -1,15 +1,19 @@
-class Hbc::CLI::InternalCheckurl < Hbc::CLI::InternalUseBase
-  def self.run(*args)
-    casks_to_check = args.empty? ? Hbc.all : args.map { |arg| Hbc.load(arg) }
-    casks_to_check.each do |cask|
-      odebug "Checking URL for Cask #{cask}"
-      checker = Hbc::UrlChecker.new(cask)
-      checker.run
-      puts checker.summary
-    end
-  end
+module Hbc
+  class CLI
+    class InternalCheckurl < InternalUseBase
+      def self.run(*args)
+        casks_to_check = args.empty? ? Hbc.all : args.map { |arg| Hbc.load(arg) }
+        casks_to_check.each do |cask|
+          odebug "Checking URL for Cask #{cask}"
+          checker = UrlChecker.new(cask)
+          checker.run
+          puts checker.summary
+        end
+      end
 
-  def self.help
-    "checks for bad Cask URLs"
+      def self.help
+        "checks for bad Cask URLs"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/internal_dump.rb b/Library/Homebrew/cask/lib/hbc/cli/internal_dump.rb
index d1cfe8d63..af1494e5f 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/internal_dump.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/internal_dump.rb
@@ -1,30 +1,34 @@
-class Hbc::CLI::InternalDump < Hbc::CLI::InternalUseBase
-  def self.run(*arguments)
-    cask_tokens = cask_tokens_from(arguments)
-    raise Hbc::CaskUnspecifiedError if cask_tokens.empty?
-    retval = dump_casks(*cask_tokens)
-    # retval is ternary: true/false/nil
+module Hbc
+  class CLI
+    class InternalDump < InternalUseBase
+      def self.run(*arguments)
+        cask_tokens = cask_tokens_from(arguments)
+        raise CaskUnspecifiedError if cask_tokens.empty?
+        retval = dump_casks(*cask_tokens)
+        # retval is ternary: true/false/nil
 
-    raise Hbc::CaskError, "nothing to dump" if retval.nil?
-    raise Hbc::CaskError, "dump incomplete" unless retval
-  end
+        raise CaskError, "nothing to dump" if retval.nil?
+        raise CaskError, "dump incomplete" unless retval
+      end
 
-  def self.dump_casks(*cask_tokens)
-    Hbc.debug = true # Yuck. At the moment this is the only way to make dumps visible
-    count = 0
-    cask_tokens.each do |cask_token|
-      begin
-        cask = Hbc.load(cask_token)
-        count += 1
-        cask.dumpcask
-      rescue StandardError => e
-        opoo "#{cask_token} was not found or would not load: #{e}"
+      def self.dump_casks(*cask_tokens)
+        Hbc.debug = true # Yuck. At the moment this is the only way to make dumps visible
+        count = 0
+        cask_tokens.each do |cask_token|
+          begin
+            cask = Hbc.load(cask_token)
+            count += 1
+            cask.dumpcask
+          rescue StandardError => e
+            opoo "#{cask_token} was not found or would not load: #{e}"
+          end
+        end
+        count.zero? ? nil : count == cask_tokens.length
       end
-    end
-    count == 0 ? nil : count == cask_tokens.length
-  end
 
-  def self.help
-    "Dump the given Cask in YAML format"
+      def self.help
+        "Dump the given Cask in YAML format"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/internal_help.rb b/Library/Homebrew/cask/lib/hbc/cli/internal_help.rb
index 81d7ee673..6c646cfd7 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/internal_help.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/internal_help.rb
@@ -1,19 +1,23 @@
-class Hbc::CLI::InternalHelp < Hbc::CLI::InternalUseBase
-  def self.run(*_ignored)
-    max_command_len = Hbc::CLI.commands.map(&:length).max
-    puts "Unstable Internal-use Commands:\n\n"
-    Hbc::CLI.command_classes.each do |klass|
-      next if klass.visible
-      puts "    #{klass.command_name.ljust(max_command_len)}  #{help_for(klass)}"
-    end
-    puts "\n"
-  end
+module Hbc
+  class CLI
+    class InternalHelp < InternalUseBase
+      def self.run(*_ignored)
+        max_command_len = CLI.commands.map(&:length).max
+        puts "Unstable Internal-use Commands:\n\n"
+        CLI.command_classes.each do |klass|
+          next if klass.visible
+          puts "    #{klass.command_name.ljust(max_command_len)}  #{help_for(klass)}"
+        end
+        puts "\n"
+      end
 
-  def self.help_for(klass)
-    klass.respond_to?(:help) ? klass.help : nil
-  end
+      def self.help_for(klass)
+        klass.respond_to?(:help) ? klass.help : nil
+      end
 
-  def self.help
-    "Print help strings for unstable internal-use commands"
+      def self.help
+        "Print help strings for unstable internal-use commands"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/internal_stanza.rb b/Library/Homebrew/cask/lib/hbc/cli/internal_stanza.rb
index 651a9ae37..0265e34b7 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/internal_stanza.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/internal_stanza.rb
@@ -1,127 +1,131 @@
-class Hbc::CLI::InternalStanza < Hbc::CLI::InternalUseBase
-  # Syntax
-  #
-  #     brew cask _stanza <stanza_name> [ --table | --yaml | --inspect | --quiet ] [ <cask_token> ... ]
-  #
-  # If no tokens are given, then data for all Casks is returned.
-  #
-  # The pseudo-stanza "artifacts" is available.
-  #
-  # On failure, a blank line is returned on the standard output.
-  #
-  # Examples
-  #
-  #     brew cask _stanza appcast   --table
-  #     brew cask _stanza app       --table alfred google-chrome adium voicemac logisim vagrant
-  #     brew cask _stanza url       --table alfred google-chrome adium voicemac logisim vagrant
-  #     brew cask _stanza version   --table alfred google-chrome adium voicemac logisim vagrant
-  #     brew cask _stanza artifacts --table --inspect alfred google-chrome adium voicemac logisim vagrant
-  #     brew cask _stanza artifacts --table --yaml    alfred google-chrome adium voicemac logisim vagrant
-  #
+module Hbc
+  class CLI
+    class InternalStanza < InternalUseBase
+      # Syntax
+      #
+      #     brew cask _stanza <stanza_name> [ --table | --yaml | --inspect | --quiet ] [ <cask_token> ... ]
+      #
+      # If no tokens are given, then data for all Casks is returned.
+      #
+      # The pseudo-stanza "artifacts" is available.
+      #
+      # On failure, a blank line is returned on the standard output.
+      #
+      # Examples
+      #
+      #     brew cask _stanza appcast   --table
+      #     brew cask _stanza app       --table alfred google-chrome adium voicemac logisim vagrant
+      #     brew cask _stanza url       --table alfred google-chrome adium voicemac logisim vagrant
+      #     brew cask _stanza version   --table alfred google-chrome adium voicemac logisim vagrant
+      #     brew cask _stanza artifacts --table --inspect alfred google-chrome adium voicemac logisim vagrant
+      #     brew cask _stanza artifacts --table --yaml    alfred google-chrome adium voicemac logisim vagrant
+      #
 
-  # TODO: this should be retrievable from Hbc::DSL
-  ARTIFACTS = Set.new [
-                        :app,
-                        :suite,
-                        :artifact,
-                        :prefpane,
-                        :qlplugin,
-                        :font,
-                        :service,
-                        :colorpicker,
-                        :binary,
-                        :input_method,
-                        :internet_plugin,
-                        :audio_unit_plugin,
-                        :vst_plugin,
-                        :vst3_plugin,
-                        :screen_saver,
-                        :pkg,
-                        :installer,
-                        :stage_only,
-                        :nested_container,
-                        :uninstall,
-                        :postflight,
-                        :uninstall_postflight,
-                        :preflight,
-                        :uninstall_postflight,
-                      ]
+      # TODO: this should be retrievable from Hbc::DSL
+      ARTIFACTS = Set.new [
+                            :app,
+                            :suite,
+                            :artifact,
+                            :prefpane,
+                            :qlplugin,
+                            :font,
+                            :service,
+                            :colorpicker,
+                            :binary,
+                            :input_method,
+                            :internet_plugin,
+                            :audio_unit_plugin,
+                            :vst_plugin,
+                            :vst3_plugin,
+                            :screen_saver,
+                            :pkg,
+                            :installer,
+                            :stage_only,
+                            :nested_container,
+                            :uninstall,
+                            :postflight,
+                            :uninstall_postflight,
+                            :preflight,
+                            :uninstall_postflight,
+                          ]
 
-  def self.run(*arguments)
-    table = arguments.include? "--table"
-    quiet = arguments.include? "--quiet"
-    format = :to_yaml if arguments.include? "--yaml"
-    format = :inspect if arguments.include? "--inspect"
-    cask_tokens = arguments.reject { |arg| arg.chars.first == "-" }
-    stanza = cask_tokens.shift.to_sym
-    cask_tokens = Hbc.all_tokens if cask_tokens.empty?
+      def self.run(*arguments)
+        table = arguments.include? "--table"
+        quiet = arguments.include? "--quiet"
+        format = :to_yaml if arguments.include? "--yaml"
+        format = :inspect if arguments.include? "--inspect"
+        cask_tokens = arguments.reject { |arg| arg.chars.first == "-" }
+        stanza = cask_tokens.shift.to_sym
+        cask_tokens = Hbc.all_tokens if cask_tokens.empty?
 
-    retval = print_stanzas(stanza, format, table, quiet, *cask_tokens)
+        retval = print_stanzas(stanza, format, table, quiet, *cask_tokens)
 
-    # retval is ternary: true/false/nil
-    if retval.nil?
-      exit 1 if quiet
-      raise Hbc::CaskError, "nothing to print"
-    elsif !retval
-      exit 1 if quiet
-      raise Hbc::CaskError, "print incomplete"
-    end
-  end
+        # retval is ternary: true/false/nil
+        if retval.nil?
+          exit 1 if quiet
+          raise CaskError, "nothing to print"
+        elsif !retval
+          exit 1 if quiet
+          raise CaskError, "print incomplete"
+        end
+      end
 
-  def self.print_stanzas(stanza, format = nil, table = nil, quiet = nil, *cask_tokens)
-    count = 0
-    if ARTIFACTS.include?(stanza)
-      artifact_name = stanza
-      stanza = :artifacts
-    end
+      def self.print_stanzas(stanza, format = nil, table = nil, quiet = nil, *cask_tokens)
+        count = 0
+        if ARTIFACTS.include?(stanza)
+          artifact_name = stanza
+          stanza = :artifacts
+        end
 
-    cask_tokens.each do |cask_token|
-      print "#{cask_token}\t" if table
+        cask_tokens.each do |cask_token|
+          print "#{cask_token}\t" if table
 
-      begin
-        cask = Hbc.load(cask_token)
-      rescue StandardError
-        opoo "Cask '#{cask_token}' was not found" unless quiet
-        puts ""
-        next
-      end
+          begin
+            cask = Hbc.load(cask_token)
+          rescue StandardError
+            opoo "Cask '#{cask_token}' was not found" unless quiet
+            puts ""
+            next
+          end
 
-      unless cask.respond_to?(stanza)
-        opoo "no such stanza '#{stanza}' on Cask '#{cask_token}'" unless quiet
-        puts ""
-        next
-      end
+          unless cask.respond_to?(stanza)
+            opoo "no such stanza '#{stanza}' on Cask '#{cask_token}'" unless quiet
+            puts ""
+            next
+          end
 
-      begin
-        value = cask.send(stanza)
-      rescue StandardError
-        opoo "failure calling '#{stanza}' on Cask '#{cask_token}'" unless quiet
-        puts ""
-        next
-      end
+          begin
+            value = cask.send(stanza)
+          rescue StandardError
+            opoo "failure calling '#{stanza}' on Cask '#{cask_token}'" unless quiet
+            puts ""
+            next
+          end
 
-      if artifact_name && !value.key?(artifact_name)
-        opoo "no such stanza '#{artifact_name}' on Cask '#{cask_token}'" unless quiet
-        puts ""
-        next
-      end
+          if artifact_name && !value.key?(artifact_name)
+            opoo "no such stanza '#{artifact_name}' on Cask '#{cask_token}'" unless quiet
+            puts ""
+            next
+          end
+
+          value = value.fetch(artifact_name).to_a.flatten if artifact_name
 
-      value = value.fetch(artifact_name).to_a.flatten if artifact_name
+          if format
+            puts value.send(format)
+          elsif artifact_name || value.is_a?(Symbol)
+            puts value.inspect
+          else
+            puts value.to_s
+          end
 
-      if format
-        puts value.send(format)
-      elsif artifact_name || value.is_a?(Symbol)
-        puts value.inspect
-      else
-        puts value.to_s
+          count += 1
+        end
+        count.zero? ? nil : count == cask_tokens.length
       end
 
-      count += 1
+      def self.help
+        "Extract and render a specific stanza for the given Casks"
+      end
     end
-    count == 0 ? nil : count == cask_tokens.length
-  end
-
-  def self.help
-    "Extract and render a specific stanza for the given Casks"
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/internal_use_base.rb b/Library/Homebrew/cask/lib/hbc/cli/internal_use_base.rb
index 6a4359ea1..96b6eeaa8 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/internal_use_base.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/internal_use_base.rb
@@ -1,9 +1,13 @@
-class Hbc::CLI::InternalUseBase < Hbc::CLI::Base
-  def self.command_name
-    super.sub(%r{^internal_}i, "_")
-  end
+module Hbc
+  class CLI
+    class InternalUseBase < Base
+      def self.command_name
+        super.sub(%r{^internal_}i, "_")
+      end
 
-  def self.visible
-    false
+      def self.visible
+        false
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/list.rb b/Library/Homebrew/cask/lib/hbc/cli/list.rb
index 88907a797..3a993f8e6 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/list.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/list.rb
@@ -1,86 +1,90 @@
-class Hbc::CLI::List < Hbc::CLI::Base
-  def self.run(*arguments)
-    @options = {}
-    @options[:one] = true if arguments.delete("-1")
-    @options[:versions] = true if arguments.delete("--versions")
+module Hbc
+  class CLI
+    class List < Base
+      def self.run(*arguments)
+        @options = {}
+        @options[:one] = true if arguments.delete("-1")
+        @options[:versions] = true if arguments.delete("--versions")
 
-    if arguments.delete("-l")
-      @options[:one] = true
-      opoo "Option -l is obsolete! Implying option -1."
-    end
+        if arguments.delete("-l")
+          @options[:one] = true
+          opoo "Option -l is obsolete! Implying option -1."
+        end
 
-    retval = arguments.any? ? list(*arguments) : list_installed
-    # retval is ternary: true/false/nil
-    if retval.nil? && !arguments.any?
-      opoo "nothing to list" # special case: avoid exit code
-    elsif retval.nil?
-      raise Hbc::CaskError, "nothing to list"
-    elsif !retval
-      raise Hbc::CaskError, "listing incomplete"
-    end
-  end
+        retval = arguments.any? ? list(*arguments) : list_installed
+        # retval is ternary: true/false/nil
+        if retval.nil? && !arguments.any?
+          opoo "nothing to list" # special case: avoid exit code
+        elsif retval.nil?
+          raise CaskError, "nothing to list"
+        elsif !retval
+          raise CaskError, "listing incomplete"
+        end
+      end
 
-  def self.list(*cask_tokens)
-    count = 0
+      def self.list(*cask_tokens)
+        count = 0
 
-    cask_tokens.each do |cask_token|
-      odebug "Listing files for Cask #{cask_token}"
-      begin
-        cask = Hbc.load(cask_token)
+        cask_tokens.each do |cask_token|
+          odebug "Listing files for Cask #{cask_token}"
+          begin
+            cask = Hbc.load(cask_token)
 
-        if cask.installed?
-          if @options[:one]
-            puts cask.token
-          elsif @options[:versions]
-            puts format_versioned(cask)
-          else
-            installed_caskfile = cask.metadata_master_container_path.join(*cask.timestamped_versions.last, "Casks", "#{cask_token}.rb")
-            cask = Hbc.load(installed_caskfile)
-            list_artifacts(cask)
-          end
+            if cask.installed?
+              if @options[:one]
+                puts cask.token
+              elsif @options[:versions]
+                puts format_versioned(cask)
+              else
+                installed_caskfile = cask.metadata_master_container_path.join(*cask.timestamped_versions.last, "Casks", "#{cask_token}.rb")
+                cask = Hbc.load(installed_caskfile)
+                list_artifacts(cask)
+              end
 
-          count += 1
-        else
-          opoo "#{cask} is not installed"
+              count += 1
+            else
+              opoo "#{cask} is not installed"
+            end
+          rescue CaskUnavailableError => e
+            onoe e
+          end
         end
-      rescue Hbc::CaskUnavailableError => e
-        onoe e
-      end
-    end
 
-    count == 0 ? nil : count == cask_tokens.length
-  end
+        count.zero? ? nil : count == cask_tokens.length
+      end
 
-  def self.list_artifacts(cask)
-    Hbc::Artifact.for_cask(cask).each do |artifact|
-      summary = artifact.new(cask).summary
-      ohai summary[:english_description], summary[:contents] unless summary.empty?
-    end
-  end
+      def self.list_artifacts(cask)
+        Artifact.for_cask(cask).each do |artifact|
+          summary = artifact.new(cask).summary
+          ohai summary[:english_description], summary[:contents] unless summary.empty?
+        end
+      end
 
-  def self.list_installed
-    installed_casks = Hbc.installed
+      def self.list_installed
+        installed_casks = Hbc.installed
 
-    if @options[:one]
-      puts installed_casks.map(&:to_s)
-    elsif @options[:versions]
-      puts installed_casks.map(&method(:format_versioned))
-    else
-      puts_columns installed_casks.map(&:to_s)
-    end
+        if @options[:one]
+          puts installed_casks.map(&:to_s)
+        elsif @options[:versions]
+          puts installed_casks.map(&method(:format_versioned))
+        else
+          puts_columns installed_casks.map(&:to_s)
+        end
 
-    installed_casks.empty? ? nil : true
-  end
+        installed_casks.empty? ? nil : true
+      end
 
-  def self.format_versioned(cask)
-    cask.to_s.concat(cask.versions.map(&:to_s).join(" ").prepend(" "))
-  end
+      def self.format_versioned(cask)
+        cask.to_s.concat(cask.versions.map(&:to_s).join(" ").prepend(" "))
+      end
 
-  def self.help
-    "with no args, lists installed Casks; given installed Casks, lists staged files"
-  end
+      def self.help
+        "with no args, lists installed Casks; given installed Casks, lists staged files"
+      end
 
-  def self.needs_init?
-    true
+      def self.needs_init?
+        true
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/search.rb b/Library/Homebrew/cask/lib/hbc/cli/search.rb
index 5c57ba43d..b671ea862 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/search.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/search.rb
@@ -1,55 +1,59 @@
-class Hbc::CLI::Search < Hbc::CLI::Base
-  def self.run(*arguments)
-    render_results(*search(*arguments))
-  end
+module Hbc
+  class CLI
+    class Search < Base
+      def self.run(*arguments)
+        render_results(*search(*arguments))
+      end
 
-  def self.extract_regexp(string)
-    if string =~ %r{^/(.*)/$}
-      Regexp.last_match[1]
-    else
-      false
-    end
-  end
+      def self.extract_regexp(string)
+        if string =~ %r{^/(.*)/$}
+          Regexp.last_match[1]
+        else
+          false
+        end
+      end
 
-  def self.search(*arguments)
-    exact_match = nil
-    partial_matches = []
-    search_term = arguments.join(" ")
-    search_regexp = extract_regexp arguments.first
-    all_tokens = Hbc::CLI.nice_listing(Hbc.all_tokens)
-    if search_regexp
-      search_term = arguments.first
-      partial_matches = all_tokens.grep(%r{#{search_regexp}}i)
-    else
-      simplified_tokens = all_tokens.map { |t| t.sub(%r{^.*\/}, "").gsub(%r{[^a-z0-9]+}i, "") }
-      simplified_search_term = search_term.sub(%r{\.rb$}i, "").gsub(%r{[^a-z0-9]+}i, "")
-      exact_match = simplified_tokens.grep(%r{^#{simplified_search_term}$}i) { |t| all_tokens[simplified_tokens.index(t)] }.first
-      partial_matches = simplified_tokens.grep(%r{#{simplified_search_term}}i) { |t| all_tokens[simplified_tokens.index(t)] }
-      partial_matches.delete(exact_match)
-    end
-    [exact_match, partial_matches, search_term]
-  end
+      def self.search(*arguments)
+        exact_match = nil
+        partial_matches = []
+        search_term = arguments.join(" ")
+        search_regexp = extract_regexp arguments.first
+        all_tokens = CLI.nice_listing(Hbc.all_tokens)
+        if search_regexp
+          search_term = arguments.first
+          partial_matches = all_tokens.grep(%r{#{search_regexp}}i)
+        else
+          simplified_tokens = all_tokens.map { |t| t.sub(%r{^.*\/}, "").gsub(%r{[^a-z0-9]+}i, "") }
+          simplified_search_term = search_term.sub(%r{\.rb$}i, "").gsub(%r{[^a-z0-9]+}i, "")
+          exact_match = simplified_tokens.grep(%r{^#{simplified_search_term}$}i) { |t| all_tokens[simplified_tokens.index(t)] }.first
+          partial_matches = simplified_tokens.grep(%r{#{simplified_search_term}}i) { |t| all_tokens[simplified_tokens.index(t)] }
+          partial_matches.delete(exact_match)
+        end
+        [exact_match, partial_matches, search_term]
+      end
 
-  def self.render_results(exact_match, partial_matches, search_term)
-    if !exact_match && partial_matches.empty?
-      puts "No Cask found for \"#{search_term}\"."
-      return
-    end
-    if exact_match
-      ohai "Exact match"
-      puts exact_match
-    end
-    unless partial_matches.empty?
-      if extract_regexp search_term
-        ohai "Regexp matches"
-      else
-        ohai "Partial matches"
+      def self.render_results(exact_match, partial_matches, search_term)
+        if !exact_match && partial_matches.empty?
+          puts "No Cask found for \"#{search_term}\"."
+          return
+        end
+        if exact_match
+          ohai "Exact match"
+          puts exact_match
+        end
+        unless partial_matches.empty?
+          if extract_regexp search_term
+            ohai "Regexp matches"
+          else
+            ohai "Partial matches"
+          end
+          puts_columns partial_matches
+        end
       end
-      puts_columns partial_matches
-    end
-  end
 
-  def self.help
-    "searches all known Casks"
+      def self.help
+        "searches all known Casks"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/style.rb b/Library/Homebrew/cask/lib/hbc/cli/style.rb
index 8793d2afd..638e25685 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/style.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/style.rb
@@ -1,69 +1,73 @@
 require "English"
 
-class Hbc::CLI::Style < Hbc::CLI::Base
-  def self.help
-    "checks Cask style using RuboCop"
-  end
+module Hbc
+  class CLI
+    class Style < Base
+      def self.help
+        "checks Cask style using RuboCop"
+      end
 
-  def self.run(*args)
-    retval = new(args).run
-    raise Hbc::CaskError, "style check failed" unless retval
-  end
+      def self.run(*args)
+        retval = new(args).run
+        raise CaskError, "style check failed" unless retval
+      end
 
-  attr_reader :args
-  def initialize(args)
-    @args = args
-  end
+      attr_reader :args
+      def initialize(args)
+        @args = args
+      end
 
-  def run
-    install_rubocop
-    system "rubocop", *rubocop_args, "--", *cask_paths
-    $CHILD_STATUS.success?
-  end
+      def run
+        install_rubocop
+        system "rubocop", *rubocop_args, "--", *cask_paths
+        $CHILD_STATUS.success?
+      end
 
-  RUBOCOP_CASK_VERSION = "~> 0.8.3".freeze
+      RUBOCOP_CASK_VERSION = "~> 0.8.3".freeze
 
-  def install_rubocop
-    Hbc::Utils.capture_stderr do
-      begin
-        Homebrew.install_gem_setup_path! "rubocop-cask", RUBOCOP_CASK_VERSION, "rubocop"
-      rescue SystemExit
-        raise Hbc::CaskError, $stderr.string.chomp.sub("#{Tty.red}Error#{Tty.reset}: ", "")
+      def install_rubocop
+        Utils.capture_stderr do
+          begin
+            Homebrew.install_gem_setup_path! "rubocop-cask", RUBOCOP_CASK_VERSION, "rubocop"
+          rescue SystemExit
+            raise CaskError, $stderr.string.chomp.sub("#{Tty.red}Error#{Tty.reset}: ", "")
+          end
+        end
       end
-    end
-  end
 
-  def cask_paths
-    @cask_paths ||= if cask_tokens.empty?
-                      Hbc.all_tapped_cask_dirs
-                    elsif cask_tokens.any? { |file| File.exist?(file) }
-                      cask_tokens
-                    else
-                      cask_tokens.map { |token| Hbc.path(token) }
-                    end
-  end
+      def cask_paths
+        @cask_paths ||= if cask_tokens.empty?
+                          Hbc.all_tapped_cask_dirs
+                        elsif cask_tokens.any? { |file| File.exist?(file) }
+                          cask_tokens
+                        else
+                          cask_tokens.map { |token| Hbc.path(token) }
+                        end
+      end
 
-  def cask_tokens
-    @cask_tokens ||= self.class.cask_tokens_from(args)
-  end
+      def cask_tokens
+        @cask_tokens ||= self.class.cask_tokens_from(args)
+      end
 
-  def rubocop_args
-    fix? ? autocorrect_args : default_args
-  end
+      def rubocop_args
+        fix? ? autocorrect_args : default_args
+      end
 
-  def default_args
-    ["--format", "simple", "--force-exclusion", "--config", rubocop_config]
-  end
+      def default_args
+        ["--format", "simple", "--force-exclusion", "--config", rubocop_config]
+      end
 
-  def autocorrect_args
-    default_args + ["--auto-correct"]
-  end
+      def autocorrect_args
+        default_args + ["--auto-correct"]
+      end
 
-  def rubocop_config
-    Hbc.default_tap.cask_dir.join(".rubocop.yml")
-  end
+      def rubocop_config
+        Hbc.default_tap.cask_dir.join(".rubocop.yml")
+      end
 
-  def fix?
-    args.any? { |arg| arg =~ %r{--(fix|(auto-?)?correct)} }
+      def fix?
+        args.any? { |arg| arg =~ %r{--(fix|(auto-?)?correct)} }
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/uninstall.rb b/Library/Homebrew/cask/lib/hbc/cli/uninstall.rb
index ae15414b7..2bebb97b0 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/uninstall.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/uninstall.rb
@@ -1,40 +1,44 @@
-class Hbc::CLI::Uninstall < Hbc::CLI::Base
-  def self.run(*args)
-    cask_tokens = cask_tokens_from(args)
-    raise Hbc::CaskUnspecifiedError if cask_tokens.empty?
-    force = args.include? "--force"
+module Hbc
+  class CLI
+    class Uninstall < Base
+      def self.run(*args)
+        cask_tokens = cask_tokens_from(args)
+        raise CaskUnspecifiedError if cask_tokens.empty?
+        force = args.include? "--force"
 
-    cask_tokens.each do |cask_token|
-      odebug "Uninstalling Cask #{cask_token}"
-      cask = Hbc.load(cask_token)
+        cask_tokens.each do |cask_token|
+          odebug "Uninstalling Cask #{cask_token}"
+          cask = Hbc.load(cask_token)
 
-      raise Hbc::CaskNotInstalledError, cask unless cask.installed? || force
+          raise CaskNotInstalledError, cask unless cask.installed? || force
 
-      latest_installed_version = cask.timestamped_versions.last
+          latest_installed_version = cask.timestamped_versions.last
 
-      unless latest_installed_version.nil?
-        latest_installed_cask_file = cask.metadata_master_container_path
-                                         .join(latest_installed_version.join(File::Separator),
-                                               "Casks", "#{cask_token}.rb")
+          unless latest_installed_version.nil?
+            latest_installed_cask_file = cask.metadata_master_container_path
+                                             .join(latest_installed_version.join(File::Separator),
+                                                   "Casks", "#{cask_token}.rb")
 
-        # use the same cask file that was used for installation, if possible
-        cask = Hbc.load(latest_installed_cask_file) if latest_installed_cask_file.exist?
-      end
+            # use the same cask file that was used for installation, if possible
+            cask = Hbc.load(latest_installed_cask_file) if latest_installed_cask_file.exist?
+          end
 
-      Hbc::Installer.new(cask, force: force).uninstall
+          Installer.new(cask, force: force).uninstall
 
-      next if (versions = cask.versions).empty?
+          next if (versions = cask.versions).empty?
 
-      single = versions.count == 1
+          single = versions.count == 1
 
-      puts <<-EOS.undent
-        #{cask_token} #{versions.join(', ')} #{single ? 'is' : 'are'} still installed.
-        Remove #{single ? 'it' : 'them all'} with `brew cask uninstall --force #{cask_token}`.
-      EOS
-    end
-  end
+          puts <<-EOS.undent
+            #{cask_token} #{versions.join(", ")} #{single ? "is" : "are"} still installed.
+            Remove #{single ? "it" : "them all"} with `brew cask uninstall --force #{cask_token}`.
+          EOS
+        end
+      end
 
-  def self.help
-    "uninstalls the given Cask"
+      def self.help
+        "uninstalls the given Cask"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/update.rb b/Library/Homebrew/cask/lib/hbc/cli/update.rb
index ceb947544..1d6ed2af5 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/update.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/update.rb
@@ -1,16 +1,20 @@
-class Hbc::CLI::Update < Hbc::CLI::Base
-  def self.run(*_ignored)
-    result = Hbc::SystemCommand.run(Hbc.homebrew_executable,
-                                    args: %w[update])
-    # TODO: separating stderr/stdout is undesirable here.
-    #       Hbc::SystemCommand should have an option for plain
-    #       unbuffered output.
-    print result.stdout
-    $stderr.print result.stderr
-    exit result.exit_status
-  end
+module Hbc
+  class CLI
+    class Update < Base
+      def self.run(*_ignored)
+        result = SystemCommand.run(Hbc.homebrew_executable,
+                                   args: %w[update])
+        # TODO: separating stderr/stdout is undesirable here.
+        #       Hbc::SystemCommand should have an option for plain
+        #       unbuffered output.
+        print result.stdout
+        $stderr.print result.stderr
+        exit result.exit_status
+      end
 
-  def self.help
-    "a synonym for 'brew update'"
+      def self.help
+        "a synonym for 'brew update'"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/cli/zap.rb b/Library/Homebrew/cask/lib/hbc/cli/zap.rb
index 081378330..2f9723858 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/zap.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/zap.rb
@@ -1,15 +1,19 @@
-class Hbc::CLI::Zap < Hbc::CLI::Base
-  def self.run(*args)
-    cask_tokens = cask_tokens_from(args)
-    raise Hbc::CaskUnspecifiedError if cask_tokens.empty?
-    cask_tokens.each do |cask_token|
-      odebug "Zapping Cask #{cask_token}"
-      cask = Hbc.load(cask_token)
-      Hbc::Installer.new(cask).zap
-    end
-  end
+module Hbc
+  class CLI
+    class Zap < Base
+      def self.run(*args)
+        cask_tokens = cask_tokens_from(args)
+        raise CaskUnspecifiedError if cask_tokens.empty?
+        cask_tokens.each do |cask_token|
+          odebug "Zapping Cask #{cask_token}"
+          cask = Hbc.load(cask_token)
+          Installer.new(cask).zap
+        end
+      end
 
-  def self.help
-    "zaps all files associated with the given Cask"
+      def self.help
+        "zaps all files associated with the given Cask"
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container.rb b/Library/Homebrew/cask/lib/hbc/container.rb
index e2b21a3ef..01dd10337 100644
--- a/Library/Homebrew/cask/lib/hbc/container.rb
+++ b/Library/Homebrew/cask/lib/hbc/container.rb
@@ -1,5 +1,3 @@
-class Hbc::Container; end
-
 require "hbc/container/base"
 require "hbc/container/air"
 require "hbc/container/bzip2"
@@ -22,47 +20,49 @@ require "hbc/container/xip"
 require "hbc/container/xz"
 require "hbc/container/zip"
 
-class Hbc::Container
-  def self.autodetect_containers
-    [
-      Hbc::Container::Pkg,
-      Hbc::Container::Ttf,
-      Hbc::Container::Otf,
-      Hbc::Container::Air,
-      Hbc::Container::Cab,
-      Hbc::Container::Dmg,
-      Hbc::Container::SevenZip,
-      Hbc::Container::Sit,
-      Hbc::Container::Rar,
-      Hbc::Container::Zip,
-      Hbc::Container::Xip,   # needs to be before xar as this is a cpio inside a gzip inside a xar
-      Hbc::Container::Xar,   # need to be before tar as tar can also list xar
-      Hbc::Container::Tar,   # or compressed tar (bzip2/gzip/lzma/xz)
-      Hbc::Container::Bzip2, # pure bzip2
-      Hbc::Container::Gzip,  # pure gzip
-      Hbc::Container::Lzma,  # pure lzma
-      Hbc::Container::Xz,    # pure xz
-    ]
-    # for explicit use only (never autodetected):
-    # Hbc::Container::Naked
-    # Hbc::Container::GenericUnar
-  end
+module Hbc
+  class Container
+    def self.autodetect_containers
+      [
+        Pkg,
+        Ttf,
+        Otf,
+        Air,
+        Cab,
+        Dmg,
+        SevenZip,
+        Sit,
+        Rar,
+        Zip,
+        Xip,   # needs to be before xar as this is a cpio inside a gzip inside a xar
+        Xar,   # need to be before tar as tar can also list xar
+        Tar,   # or compressed tar (bzip2/gzip/lzma/xz)
+        Bzip2, # pure bzip2
+        Gzip,  # pure gzip
+        Lzma,  # pure lzma
+        Xz,    # pure xz
+      ]
+      # for explicit use only (never autodetected):
+      # Hbc::Container::Naked
+      # Hbc::Container::GenericUnar
+    end
 
-  def self.for_path(path, command)
-    odebug "Determining which containers to use based on filetype"
-    criteria = Hbc::Container::Criteria.new(path, command)
-    autodetect_containers.find do |c|
-      odebug "Checking container class #{c}"
-      c.me?(criteria)
+    def self.for_path(path, command)
+      odebug "Determining which containers to use based on filetype"
+      criteria = Criteria.new(path, command)
+      autodetect_containers.find do |c|
+        odebug "Checking container class #{c}"
+        c.me?(criteria)
+      end
     end
-  end
 
-  def self.from_type(type)
-    odebug "Determining which containers to use based on 'container :type'"
-    begin
-      Hbc::Container.const_get(type.to_s.split("_").map(&:capitalize).join)
-    rescue NameError
-      false
+    def self.from_type(type)
+      odebug "Determining which containers to use based on 'container :type'"
+      begin
+        self.const_get(type.to_s.split("_").map(&:capitalize).join)
+      rescue NameError
+        false
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/air.rb b/Library/Homebrew/cask/lib/hbc/container/air.rb
index fc618db83..4b083e538 100644
--- a/Library/Homebrew/cask/lib/hbc/container/air.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/air.rb
@@ -1,33 +1,37 @@
 require "hbc/container/base"
 
-class Hbc::Container::Air < Hbc::Container::Base
-  INSTALLER_PATHNAME =
-    Pathname("/Applications/Utilities/Adobe AIR Application Installer.app" \
-             "/Contents/MacOS/Adobe AIR Application Installer")
-
-  def self.me?(criteria)
-    %w[.air].include?(criteria.path.extname)
-  end
-
-  def self.installer_cmd
-    return @installer_cmd ||= INSTALLER_PATHNAME if installer_exist?
-    raise Hbc::CaskError, <<-EOS.undent
-      Adobe AIR runtime not present, try installing it via
-
-          brew cask install adobe-air
-
-    EOS
-  end
-
-  def self.installer_exist?
-    INSTALLER_PATHNAME.exist?
-  end
-
-  def extract
-    install = @command.run(self.class.installer_cmd,
-                           args: ["-silent", "-location", @cask.staged_path, Pathname.new(@path).realpath])
-
-    return unless install.exit_status == 9
-    raise Hbc::CaskError, "Adobe AIR application #{@cask} already exists on the system, and cannot be reinstalled."
+module Hbc
+  class Container
+    class Air < Base
+      INSTALLER_PATHNAME =
+        Pathname("/Applications/Utilities/Adobe AIR Application Installer.app" \
+                 "/Contents/MacOS/Adobe AIR Application Installer")
+
+      def self.me?(criteria)
+        %w[.air].include?(criteria.path.extname)
+      end
+
+      def self.installer_cmd
+        return @installer_cmd ||= INSTALLER_PATHNAME if installer_exist?
+        raise CaskError, <<-EOS.undent
+          Adobe AIR runtime not present, try installing it via
+
+              brew cask install adobe-air
+
+        EOS
+      end
+
+      def self.installer_exist?
+        INSTALLER_PATHNAME.exist?
+      end
+
+      def extract
+        install = @command.run(self.class.installer_cmd,
+                               args: ["-silent", "-location", @cask.staged_path, Pathname.new(@path).realpath])
+
+        return unless install.exit_status == 9
+        raise CaskError, "Adobe AIR application #{@cask} already exists on the system, and cannot be reinstalled."
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/base.rb b/Library/Homebrew/cask/lib/hbc/container/base.rb
index 42331df31..1f1c9ad9b 100644
--- a/Library/Homebrew/cask/lib/hbc/container/base.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/base.rb
@@ -1,37 +1,41 @@
-class Hbc::Container::Base
-  def initialize(cask, path, command, nested: false)
-    @cask = cask
-    @path = path
-    @command = command
-    @nested = nested
-  end
+module Hbc
+  class Container
+    class Base
+      def initialize(cask, path, command, nested: false)
+        @cask = cask
+        @path = path
+        @command = command
+        @nested = nested
+      end
 
-  def extract_nested_inside(dir)
-    children = Pathname.new(dir).children
+      def extract_nested_inside(dir)
+        children = Pathname.new(dir).children
 
-    nested_container = children[0]
+        nested_container = children[0]
 
-    unless children.count == 1 &&
-           !nested_container.directory? &&
-           @cask.artifacts[:nested_container].empty? &&
-           extract_nested_container(nested_container)
+        unless children.count == 1 &&
+               !nested_container.directory? &&
+               @cask.artifacts[:nested_container].empty? &&
+               extract_nested_container(nested_container)
 
-      children.each do |src|
-        dest = @cask.staged_path.join(src.basename)
-        FileUtils.rm_r(dest) if dest.exist?
-        FileUtils.mv(src, dest)
+          children.each do |src|
+            dest = @cask.staged_path.join(src.basename)
+            FileUtils.rm_r(dest) if dest.exist?
+            FileUtils.mv(src, dest)
+          end
+        end
       end
-    end
-  end
 
-  def extract_nested_container(source)
-    container = Hbc::Container.for_path(source, @command)
+      def extract_nested_container(source)
+        container = Container.for_path(source, @command)
 
-    return false unless container
+        return false unless container
 
-    ohai "Extracting nested container #{source.basename}"
-    container.new(@cask, source, @command, nested: true).extract
+        ohai "Extracting nested container #{source.basename}"
+        container.new(@cask, source, @command, nested: true).extract
 
-    true
+        true
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/bzip2.rb b/Library/Homebrew/cask/lib/hbc/container/bzip2.rb
index 617c68b32..81808071f 100644
--- a/Library/Homebrew/cask/lib/hbc/container/bzip2.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/bzip2.rb
@@ -2,17 +2,21 @@ require "tmpdir"
 
 require "hbc/container/base"
 
-class Hbc::Container::Bzip2 < Hbc::Container::Base
-  def self.me?(criteria)
-    criteria.magic_number(%r{^BZh}n)
-  end
+module Hbc
+  class Container
+    class Bzip2 < Base
+      def self.me?(criteria)
+        criteria.magic_number(%r{^BZh}n)
+      end
 
-  def extract
-    Dir.mktmpdir do |unpack_dir|
-      @command.run!("/usr/bin/ditto",   args: ["--", @path, unpack_dir])
-      @command.run!("/usr/bin/bunzip2", args: ["--quiet", "--", Pathname.new(unpack_dir).join(@path.basename)])
+      def extract
+        Dir.mktmpdir do |unpack_dir|
+          @command.run!("/usr/bin/ditto",   args: ["--", @path, unpack_dir])
+          @command.run!("/usr/bin/bunzip2", args: ["--quiet", "--", Pathname.new(unpack_dir).join(@path.basename)])
 
-      extract_nested_inside(unpack_dir)
+          extract_nested_inside(unpack_dir)
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/cab.rb b/Library/Homebrew/cask/lib/hbc/container/cab.rb
index 28000a5a3..d32b1b205 100644
--- a/Library/Homebrew/cask/lib/hbc/container/cab.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/cab.rb
@@ -2,25 +2,29 @@ require "tmpdir"
 
 require "hbc/container/base"
 
-class Hbc::Container::Cab < Hbc::Container::Base
-  def self.me?(criteria)
-    cabextract = Hbc.homebrew_prefix.join("bin", "cabextract")
+module Hbc
+  class Container
+    class Cab < Base
+      def self.me?(criteria)
+        cabextract = Hbc.homebrew_prefix.join("bin", "cabextract")
 
-    criteria.magic_number(%r{^MSCF}n) &&
-      cabextract.exist? &&
-      criteria.command.run(cabextract, args: ["-t", "--", criteria.path.to_s]).stderr.empty?
-  end
+        criteria.magic_number(%r{^MSCF}n) &&
+          cabextract.exist? &&
+          criteria.command.run(cabextract, args: ["-t", "--", criteria.path.to_s]).stderr.empty?
+      end
 
-  def extract
-    cabextract = Hbc.homebrew_prefix.join("bin", "cabextract")
+      def extract
+        cabextract = Hbc.homebrew_prefix.join("bin", "cabextract")
 
-    unless cabextract.exist?
-      raise Hbc::CaskError, "Expected to find cabextract executable. Cask '#{@cask}' must add: depends_on formula: 'cabextract'"
-    end
+        unless cabextract.exist?
+          raise CaskError, "Expected to find cabextract executable. Cask '#{@cask}' must add: depends_on formula: 'cabextract'"
+        end
 
-    Dir.mktmpdir do |unpack_dir|
-      @command.run!(cabextract, args: ["-d", unpack_dir, "--", @path])
-      @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
+        Dir.mktmpdir do |unpack_dir|
+          @command.run!(cabextract, args: ["-d", unpack_dir, "--", @path])
+          @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/criteria.rb b/Library/Homebrew/cask/lib/hbc/container/criteria.rb
index 2ebb9d6fa..207c5f3cd 100644
--- a/Library/Homebrew/cask/lib/hbc/container/criteria.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/criteria.rb
@@ -1,18 +1,22 @@
-class Hbc::Container::Criteria
-  attr_reader :path, :command
+module Hbc
+  class Container
+    class Criteria
+      attr_reader :path, :command
 
-  def initialize(path, command)
-    @path = path
-    @command = command
-  end
+      def initialize(path, command)
+        @path = path
+        @command = command
+      end
 
-  def extension(regex)
-    path.extname.sub(%r{^\.}, "") =~ Regexp.new(regex.source, regex.options | Regexp::IGNORECASE)
-  end
+      def extension(regex)
+        path.extname.sub(%r{^\.}, "") =~ Regexp.new(regex.source, regex.options | Regexp::IGNORECASE)
+      end
 
-  def magic_number(regex)
-    # 262: length of the longest regex (currently: Hbc::Container::Tar)
-    @magic_number ||= File.open(@path, "rb") { |f| f.read(262) }
-    @magic_number =~ regex
+      def magic_number(regex)
+        # 262: length of the longest regex (currently: Hbc::Container::Tar)
+        @magic_number ||= File.open(@path, "rb") { |f| f.read(262) }
+        @magic_number =~ regex
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/dmg.rb b/Library/Homebrew/cask/lib/hbc/container/dmg.rb
index 7e4b9340d..d53c077cb 100644
--- a/Library/Homebrew/cask/lib/hbc/container/dmg.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/dmg.rb
@@ -3,123 +3,127 @@ require "tempfile"
 
 require "hbc/container/base"
 
-class Hbc::Container::Dmg < Hbc::Container::Base
-  def self.me?(criteria)
-    !criteria.command.run("/usr/bin/hdiutil",
-                          # realpath is a failsafe against unusual filenames
-                          args:         ["imageinfo", Pathname.new(criteria.path).realpath],
-                          print_stderr: false).stdout.empty?
-  end
+module Hbc
+  class Container
+    class Dmg < Base
+      def self.me?(criteria)
+        !criteria.command.run("/usr/bin/hdiutil",
+                              # realpath is a failsafe against unusual filenames
+                              args:         ["imageinfo", Pathname.new(criteria.path).realpath],
+                              print_stderr: false).stdout.empty?
+      end
 
-  attr_reader :mounts
-  def initialize(*args)
-    super(*args)
-    @mounts = []
-  end
+      attr_reader :mounts
+      def initialize(*args)
+        super(*args)
+        @mounts = []
+      end
 
-  def extract
-    mount!
-    assert_mounts_found
-    extract_mounts
-  ensure
-    eject!
-  end
+      def extract
+        mount!
+        assert_mounts_found
+        extract_mounts
+      ensure
+        eject!
+      end
 
-  def mount!
-    plist = @command.run!("/usr/bin/hdiutil",
-                          # realpath is a failsafe against unusual filenames
-                          args:  %w[mount -plist -nobrowse -readonly -noidme -mountrandom /tmp] + [Pathname.new(@path).realpath],
-                          input: %w[y])
-                    .plist
-    @mounts = mounts_from_plist(plist)
-  end
+      def mount!
+        plist = @command.run!("/usr/bin/hdiutil",
+                              # realpath is a failsafe against unusual filenames
+                              args:  %w[mount -plist -nobrowse -readonly -noidme -mountrandom /tmp] + [Pathname.new(@path).realpath],
+                              input: %w[y])
+                        .plist
+        @mounts = mounts_from_plist(plist)
+      end
 
-  def eject!
-    @mounts.each do |mount|
-      # realpath is a failsafe against unusual filenames
-      mountpath = Pathname.new(mount).realpath
-      next unless mountpath.exist?
-
-      begin
-        tries ||= 2
-        @command.run("/usr/sbin/diskutil",
-                     args:         ["eject", mountpath],
-                     print_stderr: false)
-
-        raise Hbc::CaskError, "Failed to eject #{mountpath}" if mountpath.exist?
-      rescue Hbc::CaskError => e
-        raise e if (tries -= 1).zero?
-        sleep 1
-        retry
+      def eject!
+        @mounts.each do |mount|
+          # realpath is a failsafe against unusual filenames
+          mountpath = Pathname.new(mount).realpath
+          next unless mountpath.exist?
+
+          begin
+            tries ||= 2
+            @command.run("/usr/sbin/diskutil",
+                         args:         ["eject", mountpath],
+                         print_stderr: false)
+
+            raise CaskError, "Failed to eject #{mountpath}" if mountpath.exist?
+          rescue CaskError => e
+            raise e if (tries -= 1).zero?
+            sleep 1
+            retry
+          end
+        end
       end
-    end
-  end
 
-  private
+      private
 
-  def extract_mounts
-    @mounts.each(&method(:extract_mount))
-  end
+      def extract_mounts
+        @mounts.each(&method(:extract_mount))
+      end
 
-  def extract_mount(mount)
-    Tempfile.open(["", ".bom"]) do |bomfile|
-      bomfile.close
+      def extract_mount(mount)
+        Tempfile.open(["", ".bom"]) do |bomfile|
+          bomfile.close
 
-      Tempfile.open(["", ".list"]) do |filelist|
-        filelist.write(bom_filelist_from_path(mount))
-        filelist.close
+          Tempfile.open(["", ".list"]) do |filelist|
+            filelist.write(bom_filelist_from_path(mount))
+            filelist.close
 
-        @command.run!("/usr/bin/mkbom", args: ["-s", "-i", filelist.path, "--", bomfile.path])
-        @command.run!("/usr/bin/ditto", args: ["--bom", bomfile.path, "--", mount, @cask.staged_path])
+            @command.run!("/usr/bin/mkbom", args: ["-s", "-i", filelist.path, "--", bomfile.path])
+            @command.run!("/usr/bin/ditto", args: ["--bom", bomfile.path, "--", mount, @cask.staged_path])
+          end
+        end
       end
-    end
-  end
 
-  def bom_filelist_from_path(mount)
-    Dir.chdir(mount) {
-      Dir.glob("**/*", File::FNM_DOTMATCH).map { |path|
-        next if skip_path?(Pathname(path))
-        path == "." ? path : path.prepend("./")
-      }.compact.join("\n").concat("\n")
-    }
-  end
+      def bom_filelist_from_path(mount)
+        Dir.chdir(mount) {
+          Dir.glob("**/*", File::FNM_DOTMATCH).map { |path|
+            next if skip_path?(Pathname(path))
+            path == "." ? path : path.prepend("./")
+          }.compact.join("\n").concat("\n")
+        }
+      end
 
-  def skip_path?(path)
-    dmg_metadata?(path) || system_dir_symlink?(path)
-  end
+      def skip_path?(path)
+        dmg_metadata?(path) || system_dir_symlink?(path)
+      end
 
-  # unnecessary DMG metadata
-  DMG_METADATA_FILES = %w[
-                         .background
-                         .com.apple.timemachine.donotpresent
-                         .DocumentRevisions-V100
-                         .DS_Store
-                         .fseventsd
-                         .MobileBackups
-                         .Spotlight-V100
-                         .TemporaryItems
-                         .Trashes
-                         .VolumeIcon.icns
-                       ].to_set.freeze
-
-  def dmg_metadata?(path)
-    relative_root = path.sub(%r{/.*}, "")
-    DMG_METADATA_FILES.include?(relative_root.basename.to_s)
-  end
+      # unnecessary DMG metadata
+      DMG_METADATA_FILES = %w[
+                             .background
+                             .com.apple.timemachine.donotpresent
+                             .DocumentRevisions-V100
+                             .DS_Store
+                             .fseventsd
+                             .MobileBackups
+                             .Spotlight-V100
+                             .TemporaryItems
+                             .Trashes
+                             .VolumeIcon.icns
+                           ].to_set.freeze
+
+      def dmg_metadata?(path)
+        relative_root = path.sub(%r{/.*}, "")
+        DMG_METADATA_FILES.include?(relative_root.basename.to_s)
+      end
 
-  def system_dir_symlink?(path)
-    # symlinks to system directories (commonly to /Applications)
-    path.symlink? && MacOS.system_dir?(path.readlink)
-  end
+      def system_dir_symlink?(path)
+        # symlinks to system directories (commonly to /Applications)
+        path.symlink? && MacOS.system_dir?(path.readlink)
+      end
 
-  def mounts_from_plist(plist)
-    return [] unless plist.respond_to?(:fetch)
-    plist.fetch("system-entities", []).map { |entity|
-      entity["mount-point"]
-    }.compact
-  end
+      def mounts_from_plist(plist)
+        return [] unless plist.respond_to?(:fetch)
+        plist.fetch("system-entities", []).map { |entity|
+          entity["mount-point"]
+        }.compact
+      end
 
-  def assert_mounts_found
-    raise Hbc::CaskError, "No mounts found in '#{@path}'; perhaps it is a bad DMG?" if @mounts.empty?
+      def assert_mounts_found
+        raise CaskError, "No mounts found in '#{@path}'; perhaps it is a bad DMG?" if @mounts.empty?
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/generic_unar.rb b/Library/Homebrew/cask/lib/hbc/container/generic_unar.rb
index 1dcc0997a..32bbc8d15 100644
--- a/Library/Homebrew/cask/lib/hbc/container/generic_unar.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/generic_unar.rb
@@ -2,25 +2,29 @@ require "tmpdir"
 
 require "hbc/container/base"
 
-class Hbc::Container::GenericUnar < Hbc::Container::Base
-  def self.me?(criteria)
-    lsar = Hbc.homebrew_prefix.join("bin", "lsar")
-    lsar.exist? &&
-      criteria.command.run(lsar,
-                           args:         ["-l", "-t", "--", criteria.path],
-                           print_stderr: false).stdout.chomp.end_with?("passed, 0 failed.")
-  end
+module Hbc
+  class Container
+    class GenericUnar < Base
+      def self.me?(criteria)
+        lsar = Hbc.homebrew_prefix.join("bin", "lsar")
+        lsar.exist? &&
+          criteria.command.run(lsar,
+                               args:         ["-l", "-t", "--", criteria.path],
+                               print_stderr: false).stdout.chomp.end_with?("passed, 0 failed.")
+      end
 
-  def extract
-    unar = Hbc.homebrew_prefix.join("bin", "unar")
+      def extract
+        unar = Hbc.homebrew_prefix.join("bin", "unar")
 
-    unless unar.exist?
-      raise Hbc::CaskError, "Expected to find unar executable. Cask #{@cask} must add: depends_on formula: 'unar'"
-    end
+        unless unar.exist?
+          raise CaskError, "Expected to find unar executable. Cask #{@cask} must add: depends_on formula: 'unar'"
+        end
 
-    Dir.mktmpdir do |unpack_dir|
-      @command.run!(unar, args: ["-force-overwrite", "-quiet", "-no-directory", "-output-directory", unpack_dir, "--", @path])
-      @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
+        Dir.mktmpdir do |unpack_dir|
+          @command.run!(unar, args: ["-force-overwrite", "-quiet", "-no-directory", "-output-directory", unpack_dir, "--", @path])
+          @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/gzip.rb b/Library/Homebrew/cask/lib/hbc/container/gzip.rb
index 161578162..7e4722a7f 100644
--- a/Library/Homebrew/cask/lib/hbc/container/gzip.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/gzip.rb
@@ -2,17 +2,21 @@ require "tmpdir"
 
 require "hbc/container/base"
 
-class Hbc::Container::Gzip < Hbc::Container::Base
-  def self.me?(criteria)
-    criteria.magic_number(%r{^\037\213}n)
-  end
+module Hbc
+  class Container
+    class Gzip < Base
+      def self.me?(criteria)
+        criteria.magic_number(%r{^\037\213}n)
+      end
 
-  def extract
-    Dir.mktmpdir do |unpack_dir|
-      @command.run!("/usr/bin/ditto",  args: ["--", @path, unpack_dir])
-      @command.run!("/usr/bin/gunzip", args: ["--quiet", "--name", "--", Pathname.new(unpack_dir).join(@path.basename)])
+      def extract
+        Dir.mktmpdir do |unpack_dir|
+          @command.run!("/usr/bin/ditto",  args: ["--", @path, unpack_dir])
+          @command.run!("/usr/bin/gunzip", args: ["--quiet", "--name", "--", Pathname.new(unpack_dir).join(@path.basename)])
 
-      extract_nested_inside(unpack_dir)
+          extract_nested_inside(unpack_dir)
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/lzma.rb b/Library/Homebrew/cask/lib/hbc/container/lzma.rb
index e538b3779..a91132b55 100644
--- a/Library/Homebrew/cask/lib/hbc/container/lzma.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/lzma.rb
@@ -2,22 +2,26 @@ require "tmpdir"
 
 require "hbc/container/base"
 
-class Hbc::Container::Lzma < Hbc::Container::Base
-  def self.me?(criteria)
-    criteria.magic_number(%r{^\]\000\000\200\000}n)
-  end
+module Hbc
+  class Container
+    class Lzma < Base
+      def self.me?(criteria)
+        criteria.magic_number(%r{^\]\000\000\200\000}n)
+      end
 
-  def extract
-    unlzma = Hbc.homebrew_prefix.join("bin", "unlzma")
+      def extract
+        unlzma = Hbc.homebrew_prefix.join("bin", "unlzma")
 
-    unless unlzma.exist?
-      raise Hbc::CaskError, "Expected to find unlzma executable. Cask '#{@cask}' must add: depends_on formula: 'lzma'"
-    end
+        unless unlzma.exist?
+          raise CaskError, "Expected to find unlzma executable. Cask '#{@cask}' must add: depends_on formula: 'lzma'"
+        end
 
-    Dir.mktmpdir do |unpack_dir|
-      @command.run!("/usr/bin/ditto", args: ["--", @path, unpack_dir])
-      @command.run!(unlzma, args: ["-q", "--", Pathname(unpack_dir).join(@path.basename)])
-      @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
+        Dir.mktmpdir do |unpack_dir|
+          @command.run!("/usr/bin/ditto", args: ["--", @path, unpack_dir])
+          @command.run!(unlzma, args: ["-q", "--", Pathname(unpack_dir).join(@path.basename)])
+          @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/naked.rb b/Library/Homebrew/cask/lib/hbc/container/naked.rb
index 596f50789..375d62f7a 100644
--- a/Library/Homebrew/cask/lib/hbc/container/naked.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/naked.rb
@@ -1,19 +1,23 @@
 require "hbc/container/base"
 
-class Hbc::Container::Naked < Hbc::Container::Base
-  # Either inherit from this class and override with self.me?(criteria),
-  # or use this class directly as "container type: :naked",
-  # in which case self.me? is not called.
-  def self.me?(*)
-    false
-  end
+module Hbc
+  class Container
+    class Naked < Base
+      # Either inherit from this class and override with self.me?(criteria),
+      # or use this class directly as "container type: :naked",
+      # in which case self.me? is not called.
+      def self.me?(*)
+        false
+      end
 
-  def extract
-    @command.run!("/usr/bin/ditto", args: ["--", @path, @cask.staged_path.join(target_file)])
-  end
+      def extract
+        @command.run!("/usr/bin/ditto", args: ["--", @path, @cask.staged_path.join(target_file)])
+      end
 
-  def target_file
-    return @path.basename if @nested
-    URI.decode(File.basename(@cask.url.path))
+      def target_file
+        return @path.basename if @nested
+        URI.decode(File.basename(@cask.url.path))
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/otf.rb b/Library/Homebrew/cask/lib/hbc/container/otf.rb
index f9a25e1ed..66222ad8d 100644
--- a/Library/Homebrew/cask/lib/hbc/container/otf.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/otf.rb
@@ -1,7 +1,11 @@
 require "hbc/container/naked"
 
-class Hbc::Container::Otf < Hbc::Container::Naked
-  def self.me?(criteria)
-    criteria.magic_number(%r{^OTTO}n)
+module Hbc
+  class Container
+    class Otf < Naked
+      def self.me?(criteria)
+        criteria.magic_number(%r{^OTTO}n)
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/pkg.rb b/Library/Homebrew/cask/lib/hbc/container/pkg.rb
index 5d2282d0f..dfd62a863 100644
--- a/Library/Homebrew/cask/lib/hbc/container/pkg.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/pkg.rb
@@ -1,9 +1,13 @@
 require "hbc/container/naked"
 
-class Hbc::Container::Pkg < Hbc::Container::Naked
-  def self.me?(criteria)
-    criteria.extension(%r{m?pkg$}) &&
-      (criteria.path.directory? ||
-       criteria.magic_number(%r{^xar!}n))
+module Hbc
+  class Container
+    class Pkg < Naked
+      def self.me?(criteria)
+        criteria.extension(%r{m?pkg$}) &&
+          (criteria.path.directory? ||
+           criteria.magic_number(%r{^xar!}n))
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/rar.rb b/Library/Homebrew/cask/lib/hbc/container/rar.rb
index 9c144006f..bcf225623 100644
--- a/Library/Homebrew/cask/lib/hbc/container/rar.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/rar.rb
@@ -1,8 +1,12 @@
 require "hbc/container/generic_unar"
 
-class Hbc::Container::Rar < Hbc::Container::GenericUnar
-  def self.me?(criteria)
-    criteria.magic_number(%r{^Rar!}n) &&
-      super
+module Hbc
+  class Container
+    class Rar < GenericUnar
+      def self.me?(criteria)
+        criteria.magic_number(%r{^Rar!}n) &&
+          super
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/seven_zip.rb b/Library/Homebrew/cask/lib/hbc/container/seven_zip.rb
index f0d183064..7a144d532 100644
--- a/Library/Homebrew/cask/lib/hbc/container/seven_zip.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/seven_zip.rb
@@ -1,9 +1,13 @@
 require "hbc/container/generic_unar"
 
-class Hbc::Container::SevenZip < Hbc::Container::GenericUnar
-  def self.me?(criteria)
-    # TODO: cover self-extracting archives
-    criteria.magic_number(%r{^7z}n) &&
-      super
+module Hbc
+  class Container
+    class SevenZip < GenericUnar
+      def self.me?(criteria)
+        # TODO: cover self-extracting archives
+        criteria.magic_number(%r{^7z}n) &&
+          super
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/sit.rb b/Library/Homebrew/cask/lib/hbc/container/sit.rb
index 155b93f3f..2d8849399 100644
--- a/Library/Homebrew/cask/lib/hbc/container/sit.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/sit.rb
@@ -1,8 +1,12 @@
 require "hbc/container/generic_unar"
 
-class Hbc::Container::Sit < Hbc::Container::GenericUnar
-  def self.me?(criteria)
-    criteria.magic_number(%r{^StuffIt}n) &&
-      super
+module Hbc
+  class Container
+    class Sit < GenericUnar
+      def self.me?(criteria)
+        criteria.magic_number(%r{^StuffIt}n) &&
+          super
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/tar.rb b/Library/Homebrew/cask/lib/hbc/container/tar.rb
index 8bc7c5f64..df77e454d 100644
--- a/Library/Homebrew/cask/lib/hbc/container/tar.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/tar.rb
@@ -2,17 +2,21 @@ require "tmpdir"
 
 require "hbc/container/base"
 
-class Hbc::Container::Tar < Hbc::Container::Base
-  def self.me?(criteria)
-    criteria.magic_number(%r{^.{257}ustar}n) ||
-      # or compressed tar (bzip2/gzip/lzma/xz)
-      IO.popen(["/usr/bin/tar", "-t", "-f", criteria.path.to_s], err: "/dev/null") { |io| !io.read(1).nil? }
-  end
+module Hbc
+  class Container
+    class Tar < Base
+      def self.me?(criteria)
+        criteria.magic_number(%r{^.{257}ustar}n) ||
+          # or compressed tar (bzip2/gzip/lzma/xz)
+          IO.popen(["/usr/bin/tar", "-t", "-f", criteria.path.to_s], err: "/dev/null") { |io| !io.read(1).nil? }
+      end
 
-  def extract
-    Dir.mktmpdir do |unpack_dir|
-      @command.run!("/usr/bin/tar", args: ["-x", "-f", @path, "-C", unpack_dir])
-      @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
+      def extract
+        Dir.mktmpdir do |unpack_dir|
+          @command.run!("/usr/bin/tar", args: ["-x", "-f", @path, "-C", unpack_dir])
+          @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/ttf.rb b/Library/Homebrew/cask/lib/hbc/container/ttf.rb
index 8d787f360..62ca29b22 100644
--- a/Library/Homebrew/cask/lib/hbc/container/ttf.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/ttf.rb
@@ -1,10 +1,14 @@
 require "hbc/container/naked"
 
-class Hbc::Container::Ttf < Hbc::Container::Naked
-  def self.me?(criteria)
-    # TrueType Font
-    criteria.magic_number(%r{^\000\001\000\000\000}n) ||
-      # Truetype Font Collection
-      criteria.magic_number(%r{^ttcf}n)
+module Hbc
+  class Container
+    class Ttf < Naked
+      def self.me?(criteria)
+        # TrueType Font
+        criteria.magic_number(%r{^\000\001\000\000\000}n) ||
+          # Truetype Font Collection
+          criteria.magic_number(%r{^ttcf}n)
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/xar.rb b/Library/Homebrew/cask/lib/hbc/container/xar.rb
index 5afc78bc5..228ab2343 100644
--- a/Library/Homebrew/cask/lib/hbc/container/xar.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/xar.rb
@@ -2,15 +2,19 @@ require "tmpdir"
 
 require "hbc/container/base"
 
-class Hbc::Container::Xar < Hbc::Container::Base
-  def self.me?(criteria)
-    criteria.magic_number(%r{^xar!}n)
-  end
+module Hbc
+  class Container
+    class Xar < Base
+      def self.me?(criteria)
+        criteria.magic_number(%r{^xar!}n)
+      end
 
-  def extract
-    Dir.mktmpdir do |unpack_dir|
-      @command.run!("/usr/bin/xar", args: ["-x", "-f", @path, "-C", unpack_dir])
-      @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
+      def extract
+        Dir.mktmpdir do |unpack_dir|
+          @command.run!("/usr/bin/xar", args: ["-x", "-f", @path, "-C", unpack_dir])
+          @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/xip.rb b/Library/Homebrew/cask/lib/hbc/container/xip.rb
index 579f28fe0..2d0f17e2e 100644
--- a/Library/Homebrew/cask/lib/hbc/container/xip.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/xip.rb
@@ -1,24 +1,28 @@
 require "tmpdir"
 
-class Hbc::Container::Xip < Hbc::Container::Base
-  def self.me?(criteria)
-    criteria.magic_number(%r{^xar!}n) &&
-      IO.popen(["/usr/bin/xar", "-t", "-f", criteria.path.to_s], err: "/dev/null") { |io| io.read =~ %r{\AContent\nMetadata\n\Z} }
-  end
-
-  def extract
-    Dir.mktmpdir do |unpack_dir|
-      begin
-        ohai "Verifying signature for #{@path.basename}"
-        @command.run!("/usr/sbin/pkgutil", args: ["--check-signature", @path])
-      rescue
-        raise "Signature check failed."
+module Hbc
+  class Container
+    class Xip < Base
+      def self.me?(criteria)
+        criteria.magic_number(%r{^xar!}n) &&
+          IO.popen(["/usr/bin/xar", "-t", "-f", criteria.path.to_s], err: "/dev/null") { |io| io.read =~ %r{\AContent\nMetadata\n\Z} }
       end
 
-      @command.run!("/usr/bin/xar", args: ["-x", "-f", @path, "Content", "-C", unpack_dir])
+      def extract
+        Dir.mktmpdir do |unpack_dir|
+          begin
+            ohai "Verifying signature for #{@path.basename}"
+            @command.run!("/usr/sbin/pkgutil", args: ["--check-signature", @path])
+          rescue
+            raise "Signature check failed."
+          end
+
+          @command.run!("/usr/bin/xar", args: ["-x", "-f", @path, "Content", "-C", unpack_dir])
 
-      Dir.chdir(@cask.staged_path) do
-        @command.run!("/usr/bin/cpio", args: ["--quiet", "-i", "-I", Pathname(unpack_dir).join("Content")])
+          Dir.chdir(@cask.staged_path) do
+            @command.run!("/usr/bin/cpio", args: ["--quiet", "-i", "-I", Pathname(unpack_dir).join("Content")])
+          end
+        end
       end
     end
   end
diff --git a/Library/Homebrew/cask/lib/hbc/container/xz.rb b/Library/Homebrew/cask/lib/hbc/container/xz.rb
index 228532943..831bef5aa 100644
--- a/Library/Homebrew/cask/lib/hbc/container/xz.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/xz.rb
@@ -2,22 +2,26 @@ require "tmpdir"
 
 require "hbc/container/base"
 
-class Hbc::Container::Xz < Hbc::Container::Base
-  def self.me?(criteria)
-    criteria.magic_number(%r{^\xFD7zXZ\x00}n)
-  end
+module Hbc
+  class Container
+    class Xz < Base
+      def self.me?(criteria)
+        criteria.magic_number(%r{^\xFD7zXZ\x00}n)
+      end
 
-  def extract
-    unxz = Hbc.homebrew_prefix.join("bin", "unxz")
+      def extract
+        unxz = Hbc.homebrew_prefix.join("bin", "unxz")
 
-    unless unxz.exist?
-      raise Hbc::CaskError, "Expected to find unxz executable. Cask '#{@cask}' must add: depends_on formula: 'xz'"
-    end
+        unless unxz.exist?
+          raise CaskError, "Expected to find unxz executable. Cask '#{@cask}' must add: depends_on formula: 'xz'"
+        end
 
-    Dir.mktmpdir do |unpack_dir|
-      @command.run!("/usr/bin/ditto", args: ["--", @path, unpack_dir])
-      @command.run!(unxz, args: ["-q", "--", Pathname(unpack_dir).join(@path.basename)])
-      @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
+        Dir.mktmpdir do |unpack_dir|
+          @command.run!("/usr/bin/ditto", args: ["--", @path, unpack_dir])
+          @command.run!(unxz, args: ["-q", "--", Pathname(unpack_dir).join(@path.basename)])
+          @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/zip.rb b/Library/Homebrew/cask/lib/hbc/container/zip.rb
index c6702fbb5..86e2d1bd6 100644
--- a/Library/Homebrew/cask/lib/hbc/container/zip.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/zip.rb
@@ -1,15 +1,19 @@
 require "hbc/container/base"
 
-class Hbc::Container::Zip < Hbc::Container::Base
-  def self.me?(criteria)
-    criteria.magic_number(%r{^PK(\003\004|\005\006)}n)
-  end
+module Hbc
+  class Container
+    class Zip < Base
+      def self.me?(criteria)
+        criteria.magic_number(%r{^PK(\003\004|\005\006)}n)
+      end
 
-  def extract
-    Dir.mktmpdir do |unpack_dir|
-      @command.run!("/usr/bin/ditto", args: ["-x", "-k", "--", @path, unpack_dir])
+      def extract
+        Dir.mktmpdir do |unpack_dir|
+          @command.run!("/usr/bin/ditto", args: ["-x", "-k", "--", @path, unpack_dir])
 
-      extract_nested_inside(unpack_dir)
+          extract_nested_inside(unpack_dir)
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/download.rb b/Library/Homebrew/cask/lib/hbc/download.rb
index 18dd7fe44..4166fc74d 100644
--- a/Library/Homebrew/cask/lib/hbc/download.rb
+++ b/Library/Homebrew/cask/lib/hbc/download.rb
@@ -1,43 +1,45 @@
 require "fileutils"
 require "hbc/verify"
 
-class Hbc::Download
-  attr_reader :cask
-
-  def initialize(cask, force: false)
-    @cask = cask
-    @force = force
-  end
-
-  def perform
-    clear_cache
-    fetch
-    downloaded_path
-  end
-
-  private
-
-  attr_reader :force
-  attr_accessor :downloaded_path
-
-  def downloader
-    @downloader ||= case cask.url.using
-                    when :svn
-                      Hbc::SubversionDownloadStrategy.new(cask)
-                    when :post
-                      Hbc::CurlPostDownloadStrategy.new(cask)
-                    else
-                      Hbc::CurlDownloadStrategy.new(cask)
-                    end
-  end
-
-  def clear_cache
-    downloader.clear_cache if force || cask.version.latest?
-  end
-
-  def fetch
-    self.downloaded_path = downloader.fetch
-  rescue StandardError => e
-    raise Hbc::CaskError, "Download failed on Cask '#{cask}' with message: #{e}"
+module Hbc
+  class Download
+    attr_reader :cask
+
+    def initialize(cask, force: false)
+      @cask = cask
+      @force = force
+    end
+
+    def perform
+      clear_cache
+      fetch
+      downloaded_path
+    end
+
+    private
+
+    attr_reader :force
+    attr_accessor :downloaded_path
+
+    def downloader
+      @downloader ||= case cask.url.using
+                      when :svn
+                        SubversionDownloadStrategy.new(cask)
+                      when :post
+                        CurlPostDownloadStrategy.new(cask)
+                      else
+                        CurlDownloadStrategy.new(cask)
+                      end
+    end
+
+    def clear_cache
+      downloader.clear_cache if force || cask.version.latest?
+    end
+
+    def fetch
+      self.downloaded_path = downloader.fetch
+    rescue StandardError => e
+      raise CaskError, "Download failed on Cask '#{cask}' with message: #{e}"
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/download_strategy.rb b/Library/Homebrew/cask/lib/hbc/download_strategy.rb
index 88ffb5050..400b9ffc8 100644
--- a/Library/Homebrew/cask/lib/hbc/download_strategy.rb
+++ b/Library/Homebrew/cask/lib/hbc/download_strategy.rb
@@ -6,327 +6,329 @@ require "cgi"
 # * Our overridden fetch methods are expected to return
 #   a value: the successfully downloaded file.
 
-class Hbc::AbstractDownloadStrategy
-  attr_reader :cask, :name, :url, :uri_object, :version
-
-  def initialize(cask, command = Hbc::SystemCommand)
-    @cask       = cask
-    @command    = command
-    # TODO: this excess of attributes is a function of integrating
-    #       with Homebrew's classes. Later we should be able to remove
-    #       these in favor of @cask
-    @name       = cask.token
-    @url        = cask.url.to_s
-    @uri_object = cask.url
-    @version    = cask.version
-  end
+module Hbc
+  class AbstractDownloadStrategy
+    attr_reader :cask, :name, :url, :uri_object, :version
+
+    def initialize(cask, command = SystemCommand)
+      @cask       = cask
+      @command    = command
+      # TODO: this excess of attributes is a function of integrating
+      #       with Homebrew's classes. Later we should be able to remove
+      #       these in favor of @cask
+      @name       = cask.token
+      @url        = cask.url.to_s
+      @uri_object = cask.url
+      @version    = cask.version
+    end
 
-  # All download strategies are expected to implement these methods
-  def fetch; end
+    # All download strategies are expected to implement these methods
+    def fetch; end
 
-  def cached_location; end
+    def cached_location; end
 
-  def clear_cache; end
-end
+    def clear_cache; end
+  end
 
-class Hbc::HbVCSDownloadStrategy < Hbc::AbstractDownloadStrategy
-  REF_TYPES = [:branch, :revision, :revisions, :tag].freeze
+  class HbVCSDownloadStrategy < AbstractDownloadStrategy
+    REF_TYPES = [:branch, :revision, :revisions, :tag].freeze
 
-  def initialize(cask, command = Hbc::SystemCommand)
-    super
-    @ref_type, @ref = extract_ref
-    @clone = Hbc.cache.join(cache_filename)
-  end
+    def initialize(cask, command = SystemCommand)
+      super
+      @ref_type, @ref = extract_ref
+      @clone = Hbc.cache.join(cache_filename)
+    end
 
-  def extract_ref
-    key = REF_TYPES.find { |type|
-      uri_object.respond_to?(type) && uri_object.send(type)
-    }
-    [key, key ? uri_object.send(key) : nil]
-  end
+    def extract_ref
+      key = REF_TYPES.find { |type|
+        uri_object.respond_to?(type) && uri_object.send(type)
+      }
+      [key, key ? uri_object.send(key) : nil]
+    end
 
-  def cache_filename
-    "#{name}--#{cache_tag}"
-  end
+    def cache_filename
+      "#{name}--#{cache_tag}"
+    end
 
-  def cache_tag
-    "__UNKNOWN__"
-  end
+    def cache_tag
+      "__UNKNOWN__"
+    end
 
-  def cached_location
-    @clone
-  end
+    def cached_location
+      @clone
+    end
 
-  def clear_cache
-    cached_location.rmtree if cached_location.exist?
+    def clear_cache
+      cached_location.rmtree if cached_location.exist?
+    end
   end
-end
 
-class Hbc::CurlDownloadStrategy < Hbc::AbstractDownloadStrategy
-  # TODO: should be part of url object
-  def mirrors
-    @mirrors ||= []
-  end
+  class CurlDownloadStrategy < AbstractDownloadStrategy
+    # TODO: should be part of url object
+    def mirrors
+      @mirrors ||= []
+    end
 
-  def tarball_path
-    @tarball_path ||= Hbc.cache.join("#{name}--#{version}#{ext}")
-  end
+    def tarball_path
+      @tarball_path ||= Hbc.cache.join("#{name}--#{version}#{ext}")
+    end
 
-  def temporary_path
-    @temporary_path ||= tarball_path.sub(%r{$}, ".incomplete")
-  end
+    def temporary_path
+      @temporary_path ||= tarball_path.sub(%r{$}, ".incomplete")
+    end
 
-  def cached_location
-    tarball_path
-  end
+    def cached_location
+      tarball_path
+    end
 
-  def clear_cache
-    [cached_location, temporary_path].each do |f|
-      next unless f.exist?
-      raise CurlDownloadStrategyError, "#{f} is in use by another process" if Hbc::Utils.file_locked?(f)
-      f.unlink
+    def clear_cache
+      [cached_location, temporary_path].each do |f|
+        next unless f.exist?
+        raise CurlDownloadStrategyError, "#{f} is in use by another process" if Utils.file_locked?(f)
+        f.unlink
+      end
     end
-  end
 
-  def downloaded_size
-    temporary_path.size? || 0
-  end
+    def downloaded_size
+      temporary_path.size? || 0
+    end
 
-  def _fetch
-    odebug "Calling curl with args #{cask_curl_args.utf8_inspect}"
-    curl(*cask_curl_args)
-  end
+    def _fetch
+      odebug "Calling curl with args #{cask_curl_args.utf8_inspect}"
+      curl(*cask_curl_args)
+    end
 
-  def fetch
-    ohai "Downloading #{@url}"
-    if tarball_path.exist?
-      puts "Already downloaded: #{tarball_path}"
-    else
-      had_incomplete_download = temporary_path.exist?
-      begin
-        File.open(temporary_path, "w+") do |f|
-          f.flock(File::LOCK_EX)
-          _fetch
-          f.flock(File::LOCK_UN)
-        end
-      rescue ErrorDuringExecution
-        # 33 == range not supported
-        # try wiping the incomplete download and retrying once
-        if $CHILD_STATUS.exitstatus == 33 && had_incomplete_download
-          ohai "Trying a full download"
-          temporary_path.unlink
-          had_incomplete_download = false
-          retry
+    def fetch
+      ohai "Downloading #{@url}"
+      if tarball_path.exist?
+        puts "Already downloaded: #{tarball_path}"
+      else
+        had_incomplete_download = temporary_path.exist?
+        begin
+          File.open(temporary_path, "w+") do |f|
+            f.flock(File::LOCK_EX)
+            _fetch
+            f.flock(File::LOCK_UN)
+          end
+        rescue ErrorDuringExecution
+          # 33 == range not supported
+          # try wiping the incomplete download and retrying once
+          if $CHILD_STATUS.exitstatus == 33 && had_incomplete_download
+            ohai "Trying a full download"
+            temporary_path.unlink
+            had_incomplete_download = false
+            retry
+          end
+
+          msg = @url
+          msg.concat("\nThe incomplete download is cached at #{temporary_path}") if temporary_path.exist?
+          raise CurlDownloadStrategyError, msg
         end
-
-        msg = @url
-        msg.concat("\nThe incomplete download is cached at #{temporary_path}") if temporary_path.exist?
-        raise CurlDownloadStrategyError, msg
+        ignore_interrupts { temporary_path.rename(tarball_path) }
       end
-      ignore_interrupts { temporary_path.rename(tarball_path) }
-    end
-    tarball_path
-  rescue CurlDownloadStrategyError
-    raise if mirrors.empty?
-    puts "Trying a mirror..."
-    @url = mirrors.shift
-    retry
-  end
+      tarball_path
+    rescue CurlDownloadStrategyError
+      raise if mirrors.empty?
+      puts "Trying a mirror..."
+      @url = mirrors.shift
+      retry
+    end
 
-  private
+    private
 
-  def cask_curl_args
-    default_curl_args.tap do |args|
-      args.concat(user_agent_args)
-      args.concat(cookies_args)
-      args.concat(referer_args)
+    def cask_curl_args
+      default_curl_args.tap do |args|
+        args.concat(user_agent_args)
+        args.concat(cookies_args)
+        args.concat(referer_args)
+      end
     end
-  end
-
-  def default_curl_args
-    [url, "-C", downloaded_size, "-o", temporary_path]
-  end
 
-  def user_agent_args
-    if uri_object.user_agent
-      ["-A", uri_object.user_agent]
-    else
-      []
+    def default_curl_args
+      [url, "-C", downloaded_size, "-o", temporary_path]
     end
-  end
 
-  def cookies_args
-    if uri_object.cookies
-      [
-        "-b",
-        # sort_by is for predictability between Ruby versions
-        uri_object
-          .cookies
-          .sort_by(&:to_s)
-          .map { |key, value| "#{CGI.escape(key.to_s)}=#{CGI.escape(value.to_s)}" }
-          .join(";"),
-      ]
-    else
-      []
+    def user_agent_args
+      if uri_object.user_agent
+        ["-A", uri_object.user_agent]
+      else
+        []
+      end
     end
-  end
 
-  def referer_args
-    if uri_object.referer
-      ["-e", uri_object.referer]
-    else
-      []
+    def cookies_args
+      if uri_object.cookies
+        [
+          "-b",
+          # sort_by is for predictability between Ruby versions
+          uri_object
+            .cookies
+            .sort_by(&:to_s)
+            .map { |key, value| "#{CGI.escape(key.to_s)}=#{CGI.escape(value.to_s)}" }
+            .join(";"),
+        ]
+      else
+        []
+      end
     end
-  end
 
-  def ext
-    Pathname.new(@url).extname
-  end
-end
+    def referer_args
+      if uri_object.referer
+        ["-e", uri_object.referer]
+      else
+        []
+      end
+    end
 
-class Hbc::CurlPostDownloadStrategy < Hbc::CurlDownloadStrategy
-  def cask_curl_args
-    super
-    default_curl_args.concat(post_args)
+    def ext
+      Pathname.new(@url).extname
+    end
   end
 
-  def post_args
-    if uri_object.data
-      # sort_by is for predictability between Ruby versions
-      uri_object
-        .data
-        .sort_by(&:to_s)
-        .map { |key, value| ["-d", "#{CGI.escape(key.to_s)}=#{CGI.escape(value.to_s)}"] }
-        .flatten
-    else
-      ["-X", "POST"]
+  class CurlPostDownloadStrategy < CurlDownloadStrategy
+    def cask_curl_args
+      super
+      default_curl_args.concat(post_args)
     end
-  end
-end
 
-class Hbc::SubversionDownloadStrategy < Hbc::HbVCSDownloadStrategy
-  def cache_tag
-    # TODO: pass versions as symbols, support :head here
-    version == "head" ? "svn-HEAD" : "svn"
+    def post_args
+      if uri_object.data
+        # sort_by is for predictability between Ruby versions
+        uri_object
+          .data
+          .sort_by(&:to_s)
+          .map { |key, value| ["-d", "#{CGI.escape(key.to_s)}=#{CGI.escape(value.to_s)}"] }
+          .flatten
+      else
+        ["-X", "POST"]
+      end
+    end
   end
 
-  def repo_valid?
-    @clone.join(".svn").directory?
-  end
+  class SubversionDownloadStrategy < HbVCSDownloadStrategy
+    def cache_tag
+      # TODO: pass versions as symbols, support :head here
+      version == "head" ? "svn-HEAD" : "svn"
+    end
 
-  def repo_url
-    `svn info '#{@clone}' 2>/dev/null`.strip[%r{^URL: (.+)$}, 1]
-  end
+    def repo_valid?
+      @clone.join(".svn").directory?
+    end
 
-  # super does not provide checks for already-existing downloads
-  def fetch
-    if tarball_path.exist?
-      puts "Already downloaded: #{tarball_path}"
-    else
-      @url = @url.sub(%r{^svn\+}, "") if @url =~ %r{^svn\+http://}
-      ohai "Checking out #{@url}"
+    def repo_url
+      `svn info '#{@clone}' 2>/dev/null`.strip[%r{^URL: (.+)$}, 1]
+    end
 
-      clear_cache unless @url.chomp("/") == repo_url || quiet_system("svn", "switch", @url, @clone)
+    # super does not provide checks for already-existing downloads
+    def fetch
+      if tarball_path.exist?
+        puts "Already downloaded: #{tarball_path}"
+      else
+        @url = @url.sub(%r{^svn\+}, "") if @url =~ %r{^svn\+http://}
+        ohai "Checking out #{@url}"
 
-      if @clone.exist? && !repo_valid?
-        puts "Removing invalid SVN repo from cache"
-        clear_cache
-      end
+        clear_cache unless @url.chomp("/") == repo_url || quiet_system("svn", "switch", @url, @clone)
 
-      case @ref_type
-      when :revision
-        fetch_repo @clone, @url, @ref
-      when :revisions
-        # nil is OK for main_revision, as fetch_repo will then get latest
-        main_revision = @ref[:trunk]
-        fetch_repo @clone, @url, main_revision, true
+        if @clone.exist? && !repo_valid?
+          puts "Removing invalid SVN repo from cache"
+          clear_cache
+        end
 
-        fetch_externals do |external_name, external_url|
-          fetch_repo @clone + external_name, external_url, @ref[external_name], true
+        case @ref_type
+        when :revision
+          fetch_repo @clone, @url, @ref
+        when :revisions
+          # nil is OK for main_revision, as fetch_repo will then get latest
+          main_revision = @ref[:trunk]
+          fetch_repo @clone, @url, main_revision, true
+
+          fetch_externals do |external_name, external_url|
+            fetch_repo @clone + external_name, external_url, @ref[external_name], true
+          end
+        else
+          fetch_repo @clone, @url
         end
-      else
-        fetch_repo @clone, @url
+        compress
       end
-      compress
+      tarball_path
     end
-    tarball_path
-  end
 
-  # This primary reason for redefining this method is the trust_cert
-  # option, controllable from the Cask definition. We also force
-  # consistent timestamps.  The rest of this method is similar to
-  # Homebrew's, but translated to local idiom.
-  def fetch_repo(target, url, revision = uri_object.revision, ignore_externals = false)
-    # Use "svn up" when the repository already exists locally.
-    # This saves on bandwidth and will have a similar effect to verifying the
-    # cache as it will make any changes to get the right revision.
-    svncommand = target.directory? ? "up" : "checkout"
-    args = [svncommand]
-
-    # SVN shipped with XCode 3.1.4 can't force a checkout.
-    args << "--force" unless MacOS.version == :leopard
-
-    # make timestamps consistent for checksumming
-    args.concat(%w[--config-option config:miscellany:use-commit-times=yes])
-
-    if uri_object.trust_cert
-      args << "--trust-server-cert"
-      args << "--non-interactive"
-    end
-
-    args << url unless target.directory?
-    args << target
-    args << "-r" << revision if revision
-    args << "--ignore-externals" if ignore_externals
-    @command.run!("/usr/bin/svn",
-                  args:         args,
-                  print_stderr: false)
-  end
+    # This primary reason for redefining this method is the trust_cert
+    # option, controllable from the Cask definition. We also force
+    # consistent timestamps.  The rest of this method is similar to
+    # Homebrew's, but translated to local idiom.
+    def fetch_repo(target, url, revision = uri_object.revision, ignore_externals = false)
+      # Use "svn up" when the repository already exists locally.
+      # This saves on bandwidth and will have a similar effect to verifying the
+      # cache as it will make any changes to get the right revision.
+      svncommand = target.directory? ? "up" : "checkout"
+      args = [svncommand]
+
+      # SVN shipped with XCode 3.1.4 can't force a checkout.
+      args << "--force" unless MacOS.version == :leopard
+
+      # make timestamps consistent for checksumming
+      args.concat(%w[--config-option config:miscellany:use-commit-times=yes])
+
+      if uri_object.trust_cert
+        args << "--trust-server-cert"
+        args << "--non-interactive"
+      end
 
-  def tarball_path
-    @tarball_path ||= cached_location.dirname.join(cached_location.basename.to_s + "-#{@cask.version}.tar")
-  end
+      args << url unless target.directory?
+      args << target
+      args << "-r" << revision if revision
+      args << "--ignore-externals" if ignore_externals
+      @command.run!("/usr/bin/svn",
+                    args:         args,
+                    print_stderr: false)
+    end
 
-  def shell_quote(str)
-    # Oh god escaping shell args.
-    # See http://notetoself.vrensk.com/2008/08/escaping-single-quotes-in-ruby-harder-than-expected/
-    str.gsub(%r{\\|'}) { |c| "\\#{c}" }
-  end
+    def tarball_path
+      @tarball_path ||= cached_location.dirname.join(cached_location.basename.to_s + "-#{@cask.version}.tar")
+    end
 
-  def fetch_externals
-    `svn propget svn:externals '#{shell_quote(@url)}'`.chomp.each_line do |line|
-      name, url = line.split(%r{\s+})
-      yield name, url
+    def shell_quote(str)
+      # Oh god escaping shell args.
+      # See http://notetoself.vrensk.com/2008/08/escaping-single-quotes-in-ruby-harder-than-expected/
+      str.gsub(%r{\\|'}) { |c| "\\#{c}" }
     end
-  end
 
-  private
-
-  # TODO/UPDATE: the tar approach explained below is fragile
-  # against challenges such as case-sensitive filesystems,
-  # and must be re-implemented.
-  #
-  # Seems nutty: we "download" the contents into a tape archive.
-  # Why?
-  # * A single file is tractable to the rest of the Cask toolchain,
-  # * An alternative would be to create a Directory container type.
-  #   However, some type of file-serialization trick would still be
-  #   needed in order to enable calculating a single checksum over
-  #   a directory.  So, in that alternative implementation, the
-  #   special cases would propagate outside this class, including
-  #   the use of tar or equivalent.
-  # * SubversionDownloadStrategy.cached_location is not versioned
-  # * tarball_path provides a needed return value for our overridden
-  #   fetch method.
-  # * We can also take this private opportunity to strip files from
-  #   the download which are protocol-specific.
-
-  def compress
-    Dir.chdir(cached_location) do
-      @command.run!("/usr/bin/tar",
-                    args:         ['-s/^\.//', "--exclude", ".svn", "-cf", Pathname.new(tarball_path), "--", "."],
-                    print_stderr: false)
+    def fetch_externals
+      `svn propget svn:externals '#{shell_quote(@url)}'`.chomp.each_line do |line|
+        name, url = line.split(%r{\s+})
+        yield name, url
+      end
+    end
+
+    private
+
+    # TODO/UPDATE: the tar approach explained below is fragile
+    # against challenges such as case-sensitive filesystems,
+    # and must be re-implemented.
+    #
+    # Seems nutty: we "download" the contents into a tape archive.
+    # Why?
+    # * A single file is tractable to the rest of the Cask toolchain,
+    # * An alternative would be to create a Directory container type.
+    #   However, some type of file-serialization trick would still be
+    #   needed in order to enable calculating a single checksum over
+    #   a directory.  So, in that alternative implementation, the
+    #   special cases would propagate outside this class, including
+    #   the use of tar or equivalent.
+    # * SubversionDownloadStrategy.cached_location is not versioned
+    # * tarball_path provides a needed return value for our overridden
+    #   fetch method.
+    # * We can also take this private opportunity to strip files from
+    #   the download which are protocol-specific.
+
+    def compress
+      Dir.chdir(cached_location) do
+        @command.run!("/usr/bin/tar",
+                      args:         ['-s/^\.//', "--exclude", ".svn", "-cf", Pathname.new(tarball_path), "--", "."],
+                      print_stderr: false)
+      end
+      clear_cache
     end
-    clear_cache
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl.rb b/Library/Homebrew/cask/lib/hbc/dsl.rb
index f39012542..83c0bf1fb 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl.rb
@@ -1,7 +1,5 @@
 require "set"
 
-class Hbc::DSL; end
-
 require "hbc/dsl/appcast"
 require "hbc/dsl/base"
 require "hbc/dsl/caveats"
@@ -18,266 +16,276 @@ require "hbc/dsl/uninstall_postflight"
 require "hbc/dsl/uninstall_preflight"
 require "hbc/dsl/version"
 
-class Hbc::DSL
-  ORDINARY_ARTIFACT_TYPES = [
-                              :app,
-                              :artifact,
-                              :audio_unit_plugin,
-                              :binary,
-                              :colorpicker,
-                              :font,
-                              :input_method,
-                              :internet_plugin,
-                              :pkg,
-                              :prefpane,
-                              :qlplugin,
-                              :screen_saver,
-                              :service,
-                              :stage_only,
-                              :suite,
-                              :vst_plugin,
-                              :vst3_plugin,
-                            ].freeze
-
-  ACTIVATABLE_ARTIFACT_TYPES = ([:installer, *ORDINARY_ARTIFACT_TYPES] - [:stage_only]).freeze
-
-  SPECIAL_ARTIFACT_TYPES = [
-                             :uninstall,
-                             :zap,
+module Hbc
+  class DSL
+    ORDINARY_ARTIFACT_TYPES = [
+                                :app,
+                                :artifact,
+                                :audio_unit_plugin,
+                                :binary,
+                                :colorpicker,
+                                :font,
+                                :input_method,
+                                :internet_plugin,
+                                :pkg,
+                                :prefpane,
+                                :qlplugin,
+                                :screen_saver,
+                                :service,
+                                :stage_only,
+                                :suite,
+                                :vst_plugin,
+                                :vst3_plugin,
+                              ].freeze
+
+    ACTIVATABLE_ARTIFACT_TYPES = ([:installer, *ORDINARY_ARTIFACT_TYPES] - [:stage_only]).freeze
+
+    SPECIAL_ARTIFACT_TYPES = [
+                               :uninstall,
+                               :zap,
+                             ].freeze
+
+    ARTIFACT_BLOCK_TYPES = [
+                             :preflight,
+                             :postflight,
+                             :uninstall_preflight,
+                             :uninstall_postflight,
                            ].freeze
 
-  ARTIFACT_BLOCK_TYPES = [
-                           :preflight,
-                           :postflight,
-                           :uninstall_preflight,
-                           :uninstall_postflight,
-                         ].freeze
-
-  DSL_METHODS = Set.new [
-                          :accessibility_access,
-                          :appcast,
-                          :artifacts,
-                          :auto_updates,
-                          :caskroom_path,
-                          :caveats,
-                          :conflicts_with,
-                          :container,
-                          :depends_on,
-                          :gpg,
-                          :homepage,
-                          :license,
-                          :name,
-                          :sha256,
-                          :staged_path,
-                          :url,
-                          :version,
-                          :appdir,
-                          *ORDINARY_ARTIFACT_TYPES,
-                          *ACTIVATABLE_ARTIFACT_TYPES,
-                          *SPECIAL_ARTIFACT_TYPES,
-                          *ARTIFACT_BLOCK_TYPES,
-                        ].freeze
-
-  attr_reader :token
-  def initialize(token)
-    @token = token
-  end
-
-  def name(*args)
-    @name ||= []
-    return @name if args.empty?
-    @name.concat(args.flatten)
-  end
+    DSL_METHODS = Set.new [
+                            :accessibility_access,
+                            :appcast,
+                            :artifacts,
+                            :auto_updates,
+                            :caskroom_path,
+                            :caveats,
+                            :conflicts_with,
+                            :container,
+                            :depends_on,
+                            :gpg,
+                            :homepage,
+                            :license,
+                            :name,
+                            :sha256,
+                            :staged_path,
+                            :url,
+                            :version,
+                            :appdir,
+                            *ORDINARY_ARTIFACT_TYPES,
+                            *ACTIVATABLE_ARTIFACT_TYPES,
+                            *SPECIAL_ARTIFACT_TYPES,
+                            *ARTIFACT_BLOCK_TYPES,
+                          ].freeze
+
+    attr_reader :token
+    def initialize(token)
+      @token = token
+    end
 
-  def assert_only_one_stanza_allowed(stanza, arg_given)
-    return unless instance_variable_defined?("@#{stanza}") && arg_given
-    raise Hbc::CaskInvalidError.new(token, "'#{stanza}' stanza may only appear once")
-  end
+    def name(*args)
+      @name ||= []
+      return @name if args.empty?
+      @name.concat(args.flatten)
+    end
 
-  def homepage(homepage = nil)
-    assert_only_one_stanza_allowed :homepage, !homepage.nil?
-    @homepage ||= homepage
-  end
+    def assert_only_one_stanza_allowed(stanza, arg_given)
+      return unless instance_variable_defined?("@#{stanza}") && arg_given
+      raise CaskInvalidError.new(token, "'#{stanza}' stanza may only appear once")
+    end
 
-  def url(*args, &block)
-    url_given = !args.empty? || block_given?
-    return @url unless url_given
-    assert_only_one_stanza_allowed :url, url_given
-    @url ||= begin
-      Hbc::URL.from(*args, &block)
-    rescue StandardError => e
-      raise Hbc::CaskInvalidError.new(token, "'url' stanza failed with: #{e}")
+    def homepage(homepage = nil)
+      assert_only_one_stanza_allowed :homepage, !homepage.nil?
+      @homepage ||= homepage
     end
-  end
 
-  def appcast(*args)
-    return @appcast if args.empty?
-    assert_only_one_stanza_allowed :appcast, !args.empty?
-    @appcast ||= begin
-      Hbc::DSL::Appcast.new(*args) unless args.empty?
-    rescue StandardError => e
-      raise Hbc::CaskInvalidError.new(token, e)
+    def url(*args, &block)
+      url_given = !args.empty? || block_given?
+      return @url unless url_given
+      assert_only_one_stanza_allowed :url, url_given
+      @url ||= begin
+        URL.from(*args, &block)
+      rescue StandardError => e
+        raise CaskInvalidError.new(token, "'url' stanza failed with: #{e}")
+      end
     end
-  end
 
-  def gpg(*args)
-    return @gpg if args.empty?
-    assert_only_one_stanza_allowed :gpg, !args.empty?
-    @gpg ||= begin
-      Hbc::DSL::Gpg.new(*args) unless args.empty?
-    rescue StandardError => e
-      raise Hbc::CaskInvalidError.new(token, e)
+    def appcast(*args)
+      return @appcast if args.empty?
+      assert_only_one_stanza_allowed :appcast, !args.empty?
+      @appcast ||= begin
+        DSL::Appcast.new(*args) unless args.empty?
+      rescue StandardError => e
+        raise CaskInvalidError.new(token, e)
+      end
     end
-  end
 
-  def container(*args)
-    return @container if args.empty?
-    # TODO: remove this constraint, and instead merge multiple container stanzas
-    assert_only_one_stanza_allowed :container, !args.empty?
-    @container ||= begin
-      Hbc::DSL::Container.new(*args) unless args.empty?
-    rescue StandardError => e
-      raise Hbc::CaskInvalidError.new(token, e)
+    def gpg(*args)
+      return @gpg if args.empty?
+      assert_only_one_stanza_allowed :gpg, !args.empty?
+      @gpg ||= begin
+        DSL::Gpg.new(*args) unless args.empty?
+      rescue StandardError => e
+        raise CaskInvalidError.new(token, e)
+      end
     end
-    # TODO: remove this backward-compatibility section after removing nested_container
-    if @container && @container.nested
-      artifacts[:nested_container] << @container.nested
+
+    def container(*args)
+      return @container if args.empty?
+      # TODO: remove this constraint, and instead merge multiple container stanzas
+      assert_only_one_stanza_allowed :container, !args.empty?
+      @container ||= begin
+        DSL::Container.new(*args) unless args.empty?
+      rescue StandardError => e
+        raise CaskInvalidError.new(token, e)
+      end
+      # TODO: remove this backward-compatibility section after removing nested_container
+      if @container && @container.nested
+        artifacts[:nested_container] << @container.nested
+      end
+      @container
     end
-    @container
-  end
 
-  SYMBOLIC_VERSIONS = Set.new [
-                                :latest,
-                              ]
+    SYMBOLIC_VERSIONS = Set.new [
+                                  :latest,
+                                ]
 
-  def version(arg = nil)
-    return @version if arg.nil?
-    assert_only_one_stanza_allowed :version, !arg.nil?
-    raise Hbc::CaskInvalidError.new(token, "invalid 'version' value: '#{arg.inspect}'") if !arg.is_a?(String) && !SYMBOLIC_VERSIONS.include?(arg)
-    @version ||= Hbc::DSL::Version.new(arg)
-  end
+    def version(arg = nil)
+      return @version if arg.nil?
+      assert_only_one_stanza_allowed :version, !arg.nil?
+      raise CaskInvalidError.new(token, "invalid 'version' value: '#{arg.inspect}'") if !arg.is_a?(String) && !SYMBOLIC_VERSIONS.include?(arg)
+      @version ||= DSL::Version.new(arg)
+    end
 
-  SYMBOLIC_SHA256S = Set.new [
-                               :no_check,
-                             ]
+    SYMBOLIC_SHA256S = Set.new [
+                                 :no_check,
+                               ]
 
-  def sha256(arg = nil)
-    return @sha256 if arg.nil?
-    assert_only_one_stanza_allowed :sha256, !arg.nil?
-    raise Hbc::CaskInvalidError.new(token, "invalid 'sha256' value: '#{arg.inspect}'") if !arg.is_a?(String) && !SYMBOLIC_SHA256S.include?(arg)
-    @sha256 ||= arg
-  end
+    def sha256(arg = nil)
+      return @sha256 if arg.nil?
+      assert_only_one_stanza_allowed :sha256, !arg.nil?
+      raise CaskInvalidError.new(token, "invalid 'sha256' value: '#{arg.inspect}'") if !arg.is_a?(String) && !SYMBOLIC_SHA256S.include?(arg)
+      @sha256 ||= arg
+    end
 
-  def license(arg = nil)
-    return @license if arg.nil?
-    assert_only_one_stanza_allowed :license, !arg.nil?
-    @license ||= begin
-      Hbc::DSL::License.new(arg) unless arg.nil?
-    rescue StandardError => e
-      raise Hbc::CaskInvalidError.new(token, e)
+    def license(arg = nil)
+      return @license if arg.nil?
+      assert_only_one_stanza_allowed :license, !arg.nil?
+      @license ||= begin
+        DSL::License.new(arg) unless arg.nil?
+      rescue StandardError => e
+        raise CaskInvalidError.new(token, e)
+      end
     end
-  end
 
-  # depends_on uses a load method so that multiple stanzas can be merged
-  def depends_on(*args)
-    return @depends_on if args.empty?
-    @depends_on ||= Hbc::DSL::DependsOn.new
-    begin
-      @depends_on.load(*args) unless args.empty?
-    rescue RuntimeError => e
-      raise Hbc::CaskInvalidError.new(token, e)
+    # depends_on uses a load method so that multiple stanzas can be merged
+    def depends_on(*args)
+      return @depends_on if args.empty?
+      @depends_on ||= DSL::DependsOn.new
+      begin
+        @depends_on.load(*args) unless args.empty?
+      rescue RuntimeError => e
+        raise CaskInvalidError.new(token, e)
+      end
+      @depends_on
     end
-    @depends_on
-  end
 
-  def conflicts_with(*args)
-    return @conflicts_with if args.empty?
-    # TODO: remove this constraint, and instead merge multiple conflicts_with stanzas
-    assert_only_one_stanza_allowed :conflicts_with, !args.empty?
-    @conflicts_with ||= begin
-      Hbc::DSL::ConflictsWith.new(*args) unless args.empty?
-    rescue StandardError => e
-      raise Hbc::CaskInvalidError.new(token, e)
+    def conflicts_with(*args)
+      return @conflicts_with if args.empty?
+      # TODO: remove this constraint, and instead merge multiple conflicts_with stanzas
+      assert_only_one_stanza_allowed :conflicts_with, !args.empty?
+      @conflicts_with ||= begin
+        DSL::ConflictsWith.new(*args) unless args.empty?
+      rescue StandardError => e
+        raise CaskInvalidError.new(token, e)
+      end
     end
-  end
 
-  def artifacts
-    @artifacts ||= Hash.new { |hash, key| hash[key] = Set.new }
-  end
+    def artifacts
+      @artifacts ||= Hash.new { |hash, key| hash[key] = Set.new }
+    end
 
-  def caskroom_path
-    @caskroom_path ||= Hbc.caskroom.join(token)
-  end
+    def caskroom_path
+      @caskroom_path ||= Hbc.caskroom.join(token)
+    end
 
-  def staged_path
-    return @staged_path if @staged_path
-    cask_version = version || :unknown
-    @staged_path = caskroom_path.join(cask_version.to_s)
-  end
+    def staged_path
+      return @staged_path if @staged_path
+      cask_version = version || :unknown
+      @staged_path = caskroom_path.join(cask_version.to_s)
+    end
 
-  def caveats(*string, &block)
-    @caveats ||= []
-    if block_given?
-      @caveats << Hbc::Caveats.new(block)
-    elsif string.any?
-      @caveats << string.map { |s| s.to_s.sub(%r{[\r\n \t]*\Z}, "\n\n") }
+    def caveats(*string, &block)
+      @caveats ||= []
+      if block_given?
+        @caveats << Hbc::Caveats.new(block)
+      elsif string.any?
+        @caveats << string.map { |s| s.to_s.sub(%r{[\r\n \t]*\Z}, "\n\n") }
+      end
+      @caveats
     end
-    @caveats
-  end
 
-  def accessibility_access(accessibility_access = nil)
-    assert_only_one_stanza_allowed :accessibility_access, !accessibility_access.nil?
-    @accessibility_access ||= accessibility_access
-  end
+    def accessibility_access(accessibility_access = nil)
+      assert_only_one_stanza_allowed :accessibility_access, !accessibility_access.nil?
+      @accessibility_access ||= accessibility_access
+    end
 
-  def auto_updates(auto_updates = nil)
-    assert_only_one_stanza_allowed :auto_updates, !auto_updates.nil?
-    @auto_updates ||= auto_updates
-  end
+    def auto_updates(auto_updates = nil)
+      assert_only_one_stanza_allowed :auto_updates, !auto_updates.nil?
+      @auto_updates ||= auto_updates
+    end
 
-  ORDINARY_ARTIFACT_TYPES.each do |type|
-    define_method(type) do |*args|
-      if type == :stage_only && args != [true]
-        raise Hbc::CaskInvalidError.new(token, "'stage_only' takes a single argument: true")
-      end
-      artifacts[type] << args
-      if artifacts.key?(:stage_only) && artifacts.keys.count > 1 &&
-         !(artifacts.keys & ACTIVATABLE_ARTIFACT_TYPES).empty?
-        raise Hbc::CaskInvalidError.new(token, "'stage_only' must be the only activatable artifact")
+    ORDINARY_ARTIFACT_TYPES.each do |type|
+      define_method(type) do |*args|
+        if type == :stage_only && args != [true]
+          raise CaskInvalidError.new(token, "'stage_only' takes a single argument: true")
+        end
+        artifacts[type] << args
+        if artifacts.key?(:stage_only) && artifacts.keys.count > 1 &&
+           !(artifacts.keys & ACTIVATABLE_ARTIFACT_TYPES).empty?
+          raise CaskInvalidError.new(token, "'stage_only' must be the only activatable artifact")
+        end
       end
     end
-  end
 
-  def installer(*args)
-    return artifacts[:installer] if args.empty?
-    artifacts[:installer] << Hbc::DSL::Installer.new(*args)
-    raise "'stage_only' must be the only activatable artifact" if artifacts.key?(:stage_only)
-  rescue StandardError => e
-    raise Hbc::CaskInvalidError.new(token, e)
-  end
+    def installer(*args)
+      return artifacts[:installer] if args.empty?
+      artifacts[:installer] << DSL::Installer.new(*args)
+      raise "'stage_only' must be the only activatable artifact" if artifacts.key?(:stage_only)
+    rescue StandardError => e
+      raise CaskInvalidError.new(token, e)
+    end
 
-  SPECIAL_ARTIFACT_TYPES.each do |type|
-    define_method(type) do |*args|
-      artifacts[type].merge(args)
+    SPECIAL_ARTIFACT_TYPES.each do |type|
+      define_method(type) do |*args|
+        artifacts[type].merge(args)
+      end
     end
-  end
 
-  ARTIFACT_BLOCK_TYPES.each do |type|
-    define_method(type) do |&block|
-      artifacts[type] << block
+    ARTIFACT_BLOCK_TYPES.each do |type|
+      define_method(type) do |&block|
+        artifacts[type] << block
+      end
     end
-  end
 
-  def method_missing(method, *)
-    Hbc::Utils.method_missing_message(method, token)
-    nil
-  end
+    def method_missing(method, *)
+      if method
+        Utils.method_missing_message(method, token)
+        nil
+      else
+        super
+      end
+    end
 
-  def appdir
-    self.class.appdir
-  end
+    def respond_to_missing?(*)
+      true
+    end
+
+    def appdir
+      self.class.appdir
+    end
 
-  def self.appdir
-    Hbc.appdir.sub(%r{\/$}, "")
+    def self.appdir
+      Hbc.appdir.sub(%r{\/$}, "")
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/appcast.rb b/Library/Homebrew/cask/lib/hbc/dsl/appcast.rb
index b02616cfe..2f1245d3d 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/appcast.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/appcast.rb
@@ -1,17 +1,21 @@
-class Hbc::DSL::Appcast
-  attr_reader :parameters, :checkpoint
+module Hbc
+  class DSL
+    class Appcast
+      attr_reader :parameters, :checkpoint
 
-  def initialize(uri, parameters = {})
-    @parameters     = parameters
-    @uri            = Hbc::UnderscoreSupportingURI.parse(uri)
-    @checkpoint     = @parameters[:checkpoint]
-  end
+      def initialize(uri, parameters = {})
+        @parameters     = parameters
+        @uri            = UnderscoreSupportingURI.parse(uri)
+        @checkpoint     = @parameters[:checkpoint]
+      end
 
-  def to_yaml
-    [@uri, @parameters].to_yaml
-  end
+      def to_yaml
+        [@uri, @parameters].to_yaml
+      end
 
-  def to_s
-    @uri.to_s
+      def to_s
+        @uri.to_s
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/base.rb b/Library/Homebrew/cask/lib/hbc/dsl/base.rb
index 4bf62014e..ccf93dae9 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/base.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/base.rb
@@ -1,21 +1,33 @@
-class Hbc::DSL::Base
-  extend Forwardable
+module Hbc
+  class DSL
+    class Base
+      extend Forwardable
 
-  def initialize(cask, command = Hbc::SystemCommand)
-    @cask = cask
-    @command = command
-  end
+      def initialize(cask, command = SystemCommand)
+        @cask = cask
+        @command = command
+      end
 
-  def_delegators :@cask, :token, :version, :caskroom_path, :staged_path, :appdir
+      def_delegators :@cask, :token, :version, :caskroom_path, :staged_path, :appdir
 
-  def system_command(executable, options = {})
-    @command.run!(executable, options)
-  end
+      def system_command(executable, options = {})
+        @command.run!(executable, options)
+      end
+
+      def method_missing(method, *)
+        if method
+          underscored_class = self.class.name.gsub(%r{([[:lower:]])([[:upper:]][[:lower:]])}, '\1_\2').downcase
+          section = underscored_class.downcase.split("::").last
+          Utils.method_missing_message(method, @cask.to_s, section)
+          nil
+        else
+          super
+        end
+      end
 
-  def method_missing(method, *)
-    underscored_class = self.class.name.gsub(%r{([[:lower:]])([[:upper:]][[:lower:]])}, '\1_\2').downcase
-    section = underscored_class.downcase.split("::").last
-    Hbc::Utils.method_missing_message(method, @cask.to_s, section)
-    nil
+      def respond_to_missing?(*)
+        true
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/caveats.rb b/Library/Homebrew/cask/lib/hbc/dsl/caveats.rb
index d872f49cb..5efd7d562 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/caveats.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/caveats.rb
@@ -5,108 +5,112 @@
 # ( The return value of the last method in the block is also sent
 #   to the output by the caller, but that feature is only for the
 #   convenience of Cask authors. )
-class Hbc::DSL::Caveats < Hbc::DSL::Base
-  def path_environment_variable(path)
-    puts <<-EOS.undent
-    To use #{@cask}, you may need to add the #{path} directory
-    to your PATH environment variable, eg (for bash shell):
+module Hbc
+  class DSL
+    class Caveats < Base
+      def path_environment_variable(path)
+        puts <<-EOS.undent
+        To use #{@cask}, you may need to add the #{path} directory
+        to your PATH environment variable, eg (for bash shell):
 
-      export PATH=#{path}:"$PATH"
+          export PATH=#{path}:"$PATH"
 
-    EOS
-  end
+        EOS
+      end
 
-  def zsh_path_helper(path)
-    puts <<-EOS.undent
-    To use #{@cask}, zsh users may need to add the following line to their
-    ~/.zprofile.  (Among other effects, #{path} will be added to the
-    PATH environment variable):
+      def zsh_path_helper(path)
+        puts <<-EOS.undent
+        To use #{@cask}, zsh users may need to add the following line to their
+        ~/.zprofile.  (Among other effects, #{path} will be added to the
+        PATH environment variable):
 
-      eval `/usr/libexec/path_helper -s`
+          eval `/usr/libexec/path_helper -s`
 
-    EOS
-  end
+        EOS
+      end
 
-  def files_in_usr_local
-    localpath = "/usr/local"
-    return unless Hbc.homebrew_prefix.to_s.downcase.start_with?(localpath)
-    puts <<-EOS.undent
-      Cask #{@cask} installs files under "#{localpath}". The presence of such
-      files can cause warnings when running "brew doctor", which is considered
-      to be a bug in Homebrew-Cask.
+      def files_in_usr_local
+        localpath = "/usr/local"
+        return unless Hbc.homebrew_prefix.to_s.downcase.start_with?(localpath)
+        puts <<-EOS.undent
+          Cask #{@cask} installs files under "#{localpath}". The presence of such
+          files can cause warnings when running "brew doctor", which is considered
+          to be a bug in Homebrew-Cask.
 
-    EOS
-  end
+        EOS
+      end
 
-  def depends_on_java(java_version = "any")
-    if java_version == "any"
-      puts <<-EOS.undent
-      #{@cask} requires Java. You can install the latest version with
+      def depends_on_java(java_version = "any")
+        if java_version == "any"
+          puts <<-EOS.undent
+          #{@cask} requires Java. You can install the latest version with
 
-        brew cask install java
+            brew cask install java
 
-      EOS
-    elsif java_version.include?("8") || java_version.include?("+")
-      puts <<-EOS.undent
-      #{@cask} requires Java #{java_version}. You can install the latest version with
+          EOS
+        elsif java_version.include?("8") || java_version.include?("+")
+          puts <<-EOS.undent
+          #{@cask} requires Java #{java_version}. You can install the latest version with
 
-        brew cask install java
+            brew cask install java
 
-      EOS
-    else
-      puts <<-EOS.undent
-      #{@cask} requires Java #{java_version}. You can install it with
+          EOS
+        else
+          puts <<-EOS.undent
+          #{@cask} requires Java #{java_version}. You can install it with
 
-        brew cask install caskroom/versions/java#{java_version}
+            brew cask install caskroom/versions/java#{java_version}
 
-      EOS
-    end
-  end
+          EOS
+        end
+      end
 
-  def logout
-    puts <<-EOS.undent
-    You must log out and log back in for the installation of #{@cask}
-    to take effect.
+      def logout
+        puts <<-EOS.undent
+        You must log out and log back in for the installation of #{@cask}
+        to take effect.
 
-    EOS
-  end
+        EOS
+      end
 
-  def reboot
-    puts <<-EOS.undent
-    You must reboot for the installation of #{@cask} to take effect.
+      def reboot
+        puts <<-EOS.undent
+        You must reboot for the installation of #{@cask} to take effect.
 
-    EOS
-  end
+        EOS
+      end
 
-  def discontinued
-    puts <<-EOS.undent
-    #{@cask} has been officially discontinued upstream.
-    It may stop working correctly (or at all) in recent versions of macOS.
+      def discontinued
+        puts <<-EOS.undent
+        #{@cask} has been officially discontinued upstream.
+        It may stop working correctly (or at all) in recent versions of macOS.
 
-    EOS
-  end
+        EOS
+      end
 
-  def free_license(web_page)
-    puts <<-EOS.undent
-    The vendor offers a free license for #{@cask} at
-      #{web_page}
+      def free_license(web_page)
+        puts <<-EOS.undent
+        The vendor offers a free license for #{@cask} at
+          #{web_page}
 
-    EOS
-  end
+        EOS
+      end
 
-  def malware(radar_number)
-    puts <<-EOS.undent
-    #{@cask} has been reported to bundle malware. Like with any app, use at your own risk.
+      def malware(radar_number)
+        puts <<-EOS.undent
+        #{@cask} has been reported to bundle malware. Like with any app, use at your own risk.
 
-    A report has been made to Apple about this app. Their certificate will hopefully be revoked.
-    See the public report at
-      https://openradar.appspot.com/#{radar_number}
+        A report has been made to Apple about this app. Their certificate will hopefully be revoked.
+        See the public report at
+          https://openradar.appspot.com/#{radar_number}
 
-    If this report is accurate, please duplicate it at
-      https://bugreport.apple.com/
-    If this report is a mistake, please let us know by opening an issue at
-      https://github.com/caskroom/homebrew-cask/issues/new
+        If this report is accurate, please duplicate it at
+          https://bugreport.apple.com/
+        If this report is a mistake, please let us know by opening an issue at
+          https://github.com/caskroom/homebrew-cask/issues/new
 
-    EOS
+        EOS
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/conflicts_with.rb b/Library/Homebrew/cask/lib/hbc/dsl/conflicts_with.rb
index b2de2cd45..e121e5373 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/conflicts_with.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/conflicts_with.rb
@@ -1,30 +1,34 @@
-class Hbc::DSL::ConflictsWith
-  VALID_KEYS = Set.new [
-                         :formula,
-                         :cask,
-                         :macos,
-                         :arch,
-                         :x11,
-                         :java,
-                       ]
+module Hbc
+  class DSL
+    class ConflictsWith
+      VALID_KEYS = Set.new [
+                             :formula,
+                             :cask,
+                             :macos,
+                             :arch,
+                             :x11,
+                             :java,
+                           ]
 
-  attr_accessor(*VALID_KEYS)
-  attr_accessor :pairs
+      attr_accessor(*VALID_KEYS)
+      attr_accessor :pairs
 
-  def initialize(pairs = {})
-    @pairs = pairs
-    pairs.each do |key, value|
-      raise "invalid conflicts_with key: '#{key.inspect}'" unless VALID_KEYS.include?(key)
-      writer_method = "#{key}=".to_sym
-      send(writer_method, value)
-    end
-  end
+      def initialize(pairs = {})
+        @pairs = pairs
+        pairs.each do |key, value|
+          raise "invalid conflicts_with key: '#{key.inspect}'" unless VALID_KEYS.include?(key)
+          writer_method = "#{key}=".to_sym
+          send(writer_method, value)
+        end
+      end
 
-  def to_yaml
-    @pairs.to_yaml
-  end
+      def to_yaml
+        @pairs.to_yaml
+      end
 
-  def to_s
-    @pairs.inspect
+      def to_s
+        @pairs.inspect
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/container.rb b/Library/Homebrew/cask/lib/hbc/dsl/container.rb
index 39f156668..56db31d97 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/container.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/container.rb
@@ -1,26 +1,30 @@
-class Hbc::DSL::Container
-  VALID_KEYS = Set.new [
-                         :type,
-                         :nested,
-                       ]
+module Hbc
+  class DSL
+    class Container
+      VALID_KEYS = Set.new [
+                             :type,
+                             :nested,
+                           ]
 
-  attr_accessor(*VALID_KEYS)
-  attr_accessor :pairs
+      attr_accessor(*VALID_KEYS)
+      attr_accessor :pairs
 
-  def initialize(pairs = {})
-    @pairs = pairs
-    pairs.each do |key, value|
-      raise "invalid container key: '#{key.inspect}'" unless VALID_KEYS.include?(key)
-      writer_method = "#{key}=".to_sym
-      send(writer_method, value)
-    end
-  end
+      def initialize(pairs = {})
+        @pairs = pairs
+        pairs.each do |key, value|
+          raise "invalid container key: '#{key.inspect}'" unless VALID_KEYS.include?(key)
+          writer_method = "#{key}=".to_sym
+          send(writer_method, value)
+        end
+      end
 
-  def to_yaml
-    @pairs.to_yaml
-  end
+      def to_yaml
+        @pairs.to_yaml
+      end
 
-  def to_s
-    @pairs.inspect
+      def to_s
+        @pairs.inspect
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/depends_on.rb b/Library/Homebrew/cask/lib/hbc/dsl/depends_on.rb
index a7dba3643..0e80938b7 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/depends_on.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/depends_on.rb
@@ -1,124 +1,128 @@
 require "rubygems"
 
-class Hbc::DSL::DependsOn
-  VALID_KEYS = Set.new [
-                         :formula,
-                         :cask,
-                         :macos,
-                         :arch,
-                         :x11,
-                         :java,
-                       ].freeze
+module Hbc
+  class DSL
+    class DependsOn
+      VALID_KEYS = Set.new [
+                             :formula,
+                             :cask,
+                             :macos,
+                             :arch,
+                             :x11,
+                             :java,
+                           ].freeze
 
-  VALID_ARCHES = {
-                   intel:    { type: :intel, bits: [32, 64] },
-                   ppc:      { type: :ppc,   bits: [32, 64] },
-                   # specific
-                   i386:     { type: :intel, bits: 32 },
-                   x86_64:   { type: :intel, bits: 64 },
-                   ppc_7400: { type: :ppc,   bits: 32 },
-                   ppc_64:   { type: :ppc,   bits: 64 },
-                 }.freeze
+      VALID_ARCHES = {
+                       intel:    { type: :intel, bits: [32, 64] },
+                       ppc:      { type: :ppc,   bits: [32, 64] },
+                       # specific
+                       i386:     { type: :intel, bits: 32 },
+                       x86_64:   { type: :intel, bits: 64 },
+                       ppc_7400: { type: :ppc,   bits: 32 },
+                       ppc_64:   { type: :ppc,   bits: 64 },
+                     }.freeze
 
-  # Intentionally undocumented: catch variant spellings.
-  ARCH_SYNONYMS = {
-                    x86_32:   :i386,
-                    x8632:    :i386,
-                    x8664:    :x86_64,
-                    intel_32: :i386,
-                    intel32:  :i386,
-                    intel_64: :x86_64,
-                    intel64:  :x86_64,
-                    amd_64:   :x86_64,
-                    amd64:    :x86_64,
-                    ppc7400:  :ppc_7400,
-                    ppc_32:   :ppc_7400,
-                    ppc32:    :ppc_7400,
-                    ppc64:    :ppc_64,
-                  }.freeze
+      # Intentionally undocumented: catch variant spellings.
+      ARCH_SYNONYMS = {
+                        x86_32:   :i386,
+                        x8632:    :i386,
+                        x8664:    :x86_64,
+                        intel_32: :i386,
+                        intel32:  :i386,
+                        intel_64: :x86_64,
+                        intel64:  :x86_64,
+                        amd_64:   :x86_64,
+                        amd64:    :x86_64,
+                        ppc7400:  :ppc_7400,
+                        ppc_32:   :ppc_7400,
+                        ppc32:    :ppc_7400,
+                        ppc64:    :ppc_64,
+                      }.freeze
 
-  attr_accessor :java
-  attr_accessor :pairs
-  attr_reader :arch, :cask, :formula, :macos, :x11
+      attr_accessor :java
+      attr_accessor :pairs
+      attr_reader :arch, :cask, :formula, :macos, :x11
 
-  def initialize
-    @pairs ||= {}
-  end
+      def initialize
+        @pairs ||= {}
+      end
 
-  def load(pairs = {})
-    pairs.each do |key, value|
-      raise "invalid depends_on key: '#{key.inspect}'" unless VALID_KEYS.include?(key)
-      writer_method = "#{key}=".to_sym
-      @pairs[key] = send(writer_method, value)
-    end
-  end
+      def load(pairs = {})
+        pairs.each do |key, value|
+          raise "invalid depends_on key: '#{key.inspect}'" unless VALID_KEYS.include?(key)
+          writer_method = "#{key}=".to_sym
+          @pairs[key] = send(writer_method, value)
+        end
+      end
 
-  def self.coerce_os_release(arg)
-    @macos_symbols ||= MacOS::Version::SYMBOLS
-    @inverted_macos_symbols ||= @macos_symbols.invert
+      def self.coerce_os_release(arg)
+        @macos_symbols ||= MacOS::Version::SYMBOLS
+        @inverted_macos_symbols ||= @macos_symbols.invert
 
-    begin
-      if arg.is_a?(Symbol)
-        Gem::Version.new(@macos_symbols.fetch(arg))
-      elsif arg =~ %r{^\s*:?([a-z]\S+)\s*$}i
-        Gem::Version.new(@macos_symbols.fetch(Regexp.last_match[1].downcase.to_sym))
-      elsif @inverted_macos_symbols.key?(arg)
-        Gem::Version.new(arg)
-      else
-        raise
+        begin
+          if arg.is_a?(Symbol)
+            Gem::Version.new(@macos_symbols.fetch(arg))
+          elsif arg =~ %r{^\s*:?([a-z]\S+)\s*$}i
+            Gem::Version.new(@macos_symbols.fetch(Regexp.last_match[1].downcase.to_sym))
+          elsif @inverted_macos_symbols.key?(arg)
+            Gem::Version.new(arg)
+          else
+            raise
+          end
+        rescue StandardError
+          raise "invalid 'depends_on macos' value: #{arg.inspect}"
+        end
       end
-    rescue StandardError
-      raise "invalid 'depends_on macos' value: #{arg.inspect}"
-    end
-  end
 
-  def formula=(*arg)
-    @formula ||= []
-    @formula.concat(Array(*arg))
-  end
+      def formula=(*arg)
+        @formula ||= []
+        @formula.concat(Array(*arg))
+      end
 
-  def cask=(*arg)
-    @cask ||= []
-    @cask.concat(Array(*arg))
-  end
+      def cask=(*arg)
+        @cask ||= []
+        @cask.concat(Array(*arg))
+      end
 
-  def macos=(*arg)
-    @macos ||= []
-    macos = if arg.count == 1 && arg.first =~ %r{^\s*(<|>|[=<>]=)\s*(\S+)\s*$}
-              raise "'depends_on macos' comparison expressions cannot be combined" unless @macos.empty?
-              operator = Regexp.last_match[1].to_sym
-              release = self.class.coerce_os_release(Regexp.last_match[2])
-              [[operator, release]]
-            else
-              raise "'depends_on macos' comparison expressions cannot be combined" if @macos.first.is_a?(Symbol)
-              Array(*arg).map { |elt|
-                self.class.coerce_os_release(elt)
-              }.sort
-            end
-    @macos.concat(macos)
-  end
+      def macos=(*arg)
+        @macos ||= []
+        macos = if arg.count == 1 && arg.first =~ %r{^\s*(<|>|[=<>]=)\s*(\S+)\s*$}
+                  raise "'depends_on macos' comparison expressions cannot be combined" unless @macos.empty?
+                  operator = Regexp.last_match[1].to_sym
+                  release = self.class.coerce_os_release(Regexp.last_match[2])
+                  [[operator, release]]
+                else
+                  raise "'depends_on macos' comparison expressions cannot be combined" if @macos.first.is_a?(Symbol)
+                  Array(*arg).map { |elt|
+                    self.class.coerce_os_release(elt)
+                  }.sort
+                end
+        @macos.concat(macos)
+      end
 
-  def arch=(*arg)
-    @arch ||= []
-    arches = Array(*arg).map { |elt|
-      elt = elt.to_s.downcase.sub(%r{^:}, "").tr("-", "_").to_sym
-      ARCH_SYNONYMS.key?(elt) ? ARCH_SYNONYMS[elt] : elt
-    }
-    invalid_arches = arches - VALID_ARCHES.keys
-    raise "invalid 'depends_on arch' values: #{invalid_arches.inspect}" unless invalid_arches.empty?
-    @arch.concat(arches.map { |arch| VALID_ARCHES[arch] })
-  end
+      def arch=(*arg)
+        @arch ||= []
+        arches = Array(*arg).map { |elt|
+          elt = elt.to_s.downcase.sub(%r{^:}, "").tr("-", "_").to_sym
+          ARCH_SYNONYMS.key?(elt) ? ARCH_SYNONYMS[elt] : elt
+        }
+        invalid_arches = arches - VALID_ARCHES.keys
+        raise "invalid 'depends_on arch' values: #{invalid_arches.inspect}" unless invalid_arches.empty?
+        @arch.concat(arches.map { |arch| VALID_ARCHES[arch] })
+      end
 
-  def x11=(arg)
-    raise "invalid 'depends_on x11' value: #{arg.inspect}" unless [true, false].include?(arg)
-    @x11 = arg
-  end
+      def x11=(arg)
+        raise "invalid 'depends_on x11' value: #{arg.inspect}" unless [true, false].include?(arg)
+        @x11 = arg
+      end
 
-  def to_yaml
-    @pairs.to_yaml
-  end
+      def to_yaml
+        @pairs.to_yaml
+      end
 
-  def to_s
-    @pairs.inspect
+      def to_s
+        @pairs.inspect
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/gpg.rb b/Library/Homebrew/cask/lib/hbc/dsl/gpg.rb
index 9496a8c05..572ede227 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/gpg.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/gpg.rb
@@ -1,43 +1,47 @@
-class Hbc::DSL::Gpg
-  KEY_PARAMETERS = Set.new [
-                             :key_id,
-                             :key_url,
-                           ]
+module Hbc
+  class DSL
+    class Gpg
+      KEY_PARAMETERS = Set.new [
+                                 :key_id,
+                                 :key_url,
+                               ]
 
-  VALID_PARAMETERS = Set.new []
-  VALID_PARAMETERS.merge KEY_PARAMETERS
+      VALID_PARAMETERS = Set.new []
+      VALID_PARAMETERS.merge KEY_PARAMETERS
 
-  attr_accessor(*VALID_PARAMETERS)
-  attr_accessor :signature
+      attr_accessor(*VALID_PARAMETERS)
+      attr_accessor :signature
 
-  def initialize(signature, parameters = {})
-    @parameters = parameters
-    @signature = Hbc::UnderscoreSupportingURI.parse(signature)
-    parameters.each do |hkey, hvalue|
-      raise "invalid 'gpg' parameter: '#{hkey.inspect}'" unless VALID_PARAMETERS.include?(hkey)
-      writer_method = "#{hkey}=".to_sym
-      hvalue = Hbc::UnderscoreSupportingURI.parse(hvalue) if hkey == :key_url
-      valid_id?(hvalue) if hkey == :key_id
-      send(writer_method, hvalue)
-    end
-    return if KEY_PARAMETERS.intersection(parameters.keys).length == 1
-    raise "'gpg' stanza must include exactly one of: '#{KEY_PARAMETERS.to_a}'"
-  end
+      def initialize(signature, parameters = {})
+        @parameters = parameters
+        @signature = UnderscoreSupportingURI.parse(signature)
+        parameters.each do |hkey, hvalue|
+          raise "invalid 'gpg' parameter: '#{hkey.inspect}'" unless VALID_PARAMETERS.include?(hkey)
+          writer_method = "#{hkey}=".to_sym
+          hvalue = UnderscoreSupportingURI.parse(hvalue) if hkey == :key_url
+          valid_id?(hvalue) if hkey == :key_id
+          send(writer_method, hvalue)
+        end
+        return if KEY_PARAMETERS.intersection(parameters.keys).length == 1
+        raise "'gpg' stanza must include exactly one of: '#{KEY_PARAMETERS.to_a}'"
+      end
 
-  def valid_id?(id)
-    legal_lengths = Set.new [8, 16, 40]
-    is_valid = id.is_a?(String) && legal_lengths.include?(id.length) && id[%r{^[0-9a-f]+$}i]
-    raise "invalid ':key_id' value: '#{id.inspect}'" unless is_valid
+      def valid_id?(id)
+        legal_lengths = Set.new [8, 16, 40]
+        is_valid = id.is_a?(String) && legal_lengths.include?(id.length) && id[%r{^[0-9a-f]+$}i]
+        raise "invalid ':key_id' value: '#{id.inspect}'" unless is_valid
 
-    is_valid
-  end
+        is_valid
+      end
 
-  def to_yaml
-    # bug, :key_url value is not represented as an instance of Hbc::UnderscoreSupportingURI
-    [@signature, @parameters].to_yaml
-  end
+      def to_yaml
+        # bug, :key_url value is not represented as an instance of Hbc::UnderscoreSupportingURI
+        [@signature, @parameters].to_yaml
+      end
 
-  def to_s
-    @signature.to_s
+      def to_s
+        @signature.to_s
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/installer.rb b/Library/Homebrew/cask/lib/hbc/dsl/installer.rb
index 74b4b3a91..92561c703 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/installer.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/installer.rb
@@ -1,28 +1,32 @@
-class Hbc::DSL::Installer
-  VALID_KEYS = Set.new [
-                         :manual,
-                         :script,
-                       ]
+module Hbc
+  class DSL
+    class Installer
+      VALID_KEYS = Set.new [
+                             :manual,
+                             :script,
+                           ]
 
-  attr_accessor(*VALID_KEYS)
+      attr_accessor(*VALID_KEYS)
 
-  def initialize(*parameters)
-    raise Hbc::CaskInvalidError.new(token, "'installer' stanza requires an argument") if parameters.empty?
-    parameters = {}.merge(*parameters)
-    if parameters.key?(:script) && !parameters[:script].respond_to?(:key?)
-      if parameters.key?(:executable)
-        raise Hbc::CaskInvalidError.new(token, "'installer' stanza gave arguments for both :script and :executable")
+      def initialize(*parameters)
+        raise CaskInvalidError.new(token, "'installer' stanza requires an argument") if parameters.empty?
+        parameters = {}.merge(*parameters)
+        if parameters.key?(:script) && !parameters[:script].respond_to?(:key?)
+          if parameters.key?(:executable)
+            raise CaskInvalidError.new(token, "'installer' stanza gave arguments for both :script and :executable")
+          end
+          parameters[:executable] = parameters[:script]
+          parameters.delete(:script)
+          parameters = { script: parameters }
+        end
+        unless parameters.keys.length == 1
+          raise "invalid 'installer' stanza: only one of #{VALID_KEYS.inspect} is permitted"
+        end
+        key = parameters.keys.first
+        raise "invalid 'installer' stanza key: '#{key.inspect}'" unless VALID_KEYS.include?(key)
+        writer_method = "#{key}=".to_sym
+        send(writer_method, parameters[key])
       end
-      parameters[:executable] = parameters[:script]
-      parameters.delete(:script)
-      parameters = { script: parameters }
     end
-    unless parameters.keys.length == 1
-      raise "invalid 'installer' stanza: only one of #{VALID_KEYS.inspect} is permitted"
-    end
-    key = parameters.keys.first
-    raise "invalid 'installer' stanza key: '#{key.inspect}'" unless VALID_KEYS.include?(key)
-    writer_method = "#{key}=".to_sym
-    send(writer_method, parameters[key])
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/license.rb b/Library/Homebrew/cask/lib/hbc/dsl/license.rb
index 5f607c268..affbc08f5 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/license.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/license.rb
@@ -1,66 +1,70 @@
-class Hbc::DSL::License
-  # a generic category can always be given as a license, so
-  # category names should be given as both key and value
-  VALID_LICENSES = {
-                     # license         category
-                     unknown:       :unknown,
+module Hbc
+  class DSL
+    class License
+      # a generic category can always be given as a license, so
+      # category names should be given as both key and value
+      VALID_LICENSES = {
+                         # license         category
+                         unknown:       :unknown,
 
-                     other:         :other,
+                         other:         :other,
 
-                     closed:        :closed,
-                     commercial:    :closed,
-                     gratis:        :closed,
-                     freemium:      :closed,
+                         closed:        :closed,
+                         commercial:    :closed,
+                         gratis:        :closed,
+                         freemium:      :closed,
 
-                     oss:           :oss,
-                     affero:        :oss,
-                     apache:        :oss,
-                     arphic:        :oss,
-                     artistic:      :oss,
-                     bsd:           :oss,
-                     cc:            :oss,
-                     eclipse:       :oss,
-                     gpl:           :oss,
-                     isc:           :oss,
-                     lppl:          :oss,
-                     ncsa:          :oss,
-                     mit:           :oss,
-                     mpl:           :oss,
-                     ofl:           :oss,
-                     public_domain: :oss,
-                     ubuntu_font:   :oss,
-                     x11:           :oss,
-                   }.freeze
+                         oss:           :oss,
+                         affero:        :oss,
+                         apache:        :oss,
+                         arphic:        :oss,
+                         artistic:      :oss,
+                         bsd:           :oss,
+                         cc:            :oss,
+                         eclipse:       :oss,
+                         gpl:           :oss,
+                         isc:           :oss,
+                         lppl:          :oss,
+                         ncsa:          :oss,
+                         mit:           :oss,
+                         mpl:           :oss,
+                         ofl:           :oss,
+                         public_domain: :oss,
+                         ubuntu_font:   :oss,
+                         x11:           :oss,
+                       }.freeze
 
-  DEFAULT_LICENSE = :unknown
-  DEFAULT_CATEGORY = VALID_LICENSES[DEFAULT_LICENSE]
+      DEFAULT_LICENSE = :unknown
+      DEFAULT_CATEGORY = VALID_LICENSES[DEFAULT_LICENSE]
 
-  attr_reader :value
+      attr_reader :value
 
-  def self.check_constants
-    categories = Set.new(VALID_LICENSES.values)
-    categories.each do |cat|
-      next if VALID_LICENSES.key?(cat)
-      raise "license category is not a value: '#{@cat.inspect}'"
-    end
-  end
+      def self.check_constants
+        categories = Set.new(VALID_LICENSES.values)
+        categories.each do |cat|
+          next if VALID_LICENSES.key?(cat)
+          raise "license category is not a value: '#{@cat.inspect}'"
+        end
+      end
 
-  def self.category(license)
-    VALID_LICENSES.fetch(license, DEFAULT_CATEGORY)
-  end
+      def self.category(license)
+        VALID_LICENSES.fetch(license, DEFAULT_CATEGORY)
+      end
 
-  def initialize(arg)
-    @value = arg
-    @value = DEFAULT_LICENSE if @value.nil?
-    return if VALID_LICENSES.key?(@value)
-    raise "invalid license value: '#{@value.inspect}'"
-  end
+      def initialize(arg)
+        @value = arg
+        @value = DEFAULT_LICENSE if @value.nil?
+        return if VALID_LICENSES.key?(@value)
+        raise "invalid license value: '#{@value.inspect}'"
+      end
 
-  def category
-    self.class.category(@value)
-  end
+      def category
+        self.class.category(@value)
+      end
 
-  def to_s
-    @value.inspect
+      def to_s
+        @value.inspect
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/postflight.rb b/Library/Homebrew/cask/lib/hbc/dsl/postflight.rb
index 321c7e81a..1026f6de6 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/postflight.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/postflight.rb
@@ -1,9 +1,13 @@
 require "hbc/staged"
 
-class Hbc::DSL::Postflight < Hbc::DSL::Base
-  include Hbc::Staged
+module Hbc
+  class DSL
+    class Postflight < Base
+      include Staged
 
-  def suppress_move_to_applications(options = {})
-    # TODO: Remove from all casks because it is no longer needed
+      def suppress_move_to_applications(options = {})
+        # TODO: Remove from all casks because it is no longer needed
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/preflight.rb b/Library/Homebrew/cask/lib/hbc/dsl/preflight.rb
index a0d53c69c..55a778706 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/preflight.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/preflight.rb
@@ -1,3 +1,7 @@
-class Hbc::DSL::Preflight < Hbc::DSL::Base
-  include Hbc::Staged
+module Hbc
+  class DSL
+    class Preflight < Base
+      include Staged
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/stanza_proxy.rb b/Library/Homebrew/cask/lib/hbc/dsl/stanza_proxy.rb
index 02c76fb27..b1a850c5a 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/stanza_proxy.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/stanza_proxy.rb
@@ -1,37 +1,49 @@
-class Hbc::DSL::StanzaProxy
-  attr_reader :type
+module Hbc
+  class DSL
+    class StanzaProxy
+      attr_reader :type
 
-  def self.once(type)
-    resolved = nil
-    new(type) { resolved ||= yield }
-  end
+      def self.once(type)
+        resolved = nil
+        new(type) { resolved ||= yield }
+      end
 
-  def initialize(type, &resolver)
-    @type = type
-    @resolver = resolver
-  end
+      def initialize(type, &resolver)
+        @type = type
+        @resolver = resolver
+      end
 
-  def proxy?
-    true
-  end
+      def proxy?
+        true
+      end
 
-  def to_s
-    @resolver.call.to_s
-  end
+      def to_s
+        @resolver.call.to_s
+      end
 
-  # Serialization for dumpcask
-  def encode_with(coder)
-    coder["type"] = type
-    coder["resolved"] = @resolver.call
-  end
+      # Serialization for dumpcask
+      def encode_with(coder)
+        coder["type"] = type
+        coder["resolved"] = @resolver.call
+      end
 
-  def respond_to?(symbol, include_private = false)
-    return true if %i{encode_with proxy? to_s type}.include?(symbol)
-    return false if symbol == :to_ary
-    @resolver.call.respond_to?(symbol, include_private)
-  end
+      def method_missing(method, *args)
+        if method != :to_ary
+          @resolver.call.send(method, *args)
+        else
+          super
+        end
+      end
+
+      def respond_to?(method, include_private = false)
+        return true if %i{encode_with proxy? to_s type}.include?(method)
+        return false if method == :to_ary
+        @resolver.call.respond_to?(method, include_private)
+      end
 
-  def method_missing(symbol, *args)
-    @resolver.call.send(symbol, *args)
+      def respond_to_missing?(*)
+        true
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/uninstall_postflight.rb b/Library/Homebrew/cask/lib/hbc/dsl/uninstall_postflight.rb
index bd8777ca7..f481cc357 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/uninstall_postflight.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/uninstall_postflight.rb
@@ -1,2 +1,6 @@
-class Hbc::DSL::UninstallPostflight < Hbc::DSL::Base
+module Hbc
+  class DSL
+    class UninstallPostflight < Base
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/uninstall_preflight.rb b/Library/Homebrew/cask/lib/hbc/dsl/uninstall_preflight.rb
index 994151c25..36cdec12f 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/uninstall_preflight.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/uninstall_preflight.rb
@@ -1,5 +1,9 @@
 require "hbc/staged"
 
-class Hbc::DSL::UninstallPreflight < Hbc::DSL::Base
-  include Hbc::Staged
+module Hbc
+  class DSL
+    class UninstallPreflight < Base
+      include Staged
+    end
+  end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/dsl/version.rb b/Library/Homebrew/cask/lib/hbc/dsl/version.rb
index e01e67ea2..d4697460a 100644
--- a/Library/Homebrew/cask/lib/hbc/dsl/version.rb
+++ b/Library/Homebrew/cask/lib/hbc/dsl/version.rb
@@ -1,111 +1,115 @@
-class Hbc::DSL::Version < ::String
-  DIVIDERS = {
-               "." => :dots,
-               "-" => :hyphens,
-               "_" => :underscores,
-               "/" => :slashes,
-             }.freeze
-
-  DIVIDER_REGEX = %r{(#{DIVIDERS.keys.map { |v| Regexp.quote(v) }.join('|')})}
-
-  MAJOR_MINOR_PATCH_REGEX = %r{^(\d+)(?:\.(\d+)(?:\.(\d+))?)?}
-
-  class << self
-    private
-
-    def define_divider_methods(divider)
-      define_divider_deletion_method(divider)
-      define_divider_conversion_methods(divider)
-    end
+module Hbc
+  class DSL
+    class Version < ::String
+      DIVIDERS = {
+                   "." => :dots,
+                   "-" => :hyphens,
+                   "_" => :underscores,
+                   "/" => :slashes,
+                 }.freeze
+
+      DIVIDER_REGEX = %r{(#{DIVIDERS.keys.map { |v| Regexp.quote(v) }.join('|')})}
+
+      MAJOR_MINOR_PATCH_REGEX = %r{^(\d+)(?:\.(\d+)(?:\.(\d+))?)?}
+
+      class << self
+        private
+
+        def define_divider_methods(divider)
+          define_divider_deletion_method(divider)
+          define_divider_conversion_methods(divider)
+        end
+
+        def define_divider_deletion_method(divider)
+          method_name = deletion_method_name(divider)
+          define_method(method_name) do
+            version { delete(divider) }
+          end
+        end
+
+        def deletion_method_name(divider)
+          "no_#{DIVIDERS[divider]}"
+        end
+
+        def define_divider_conversion_methods(left_divider)
+          (DIVIDERS.keys - [left_divider]).each do |right_divider|
+            define_divider_conversion_method(left_divider, right_divider)
+          end
+        end
+
+        def define_divider_conversion_method(left_divider, right_divider)
+          method_name = conversion_method_name(left_divider, right_divider)
+          define_method(method_name) do
+            version { gsub(left_divider, right_divider) }
+          end
+        end
+
+        def conversion_method_name(left_divider, right_divider)
+          "#{DIVIDERS[left_divider]}_to_#{DIVIDERS[right_divider]}"
+        end
+      end
 
-    def define_divider_deletion_method(divider)
-      method_name = deletion_method_name(divider)
-      define_method(method_name) do
-        version { delete(divider) }
+      DIVIDERS.keys.each do |divider|
+        define_divider_methods(divider)
       end
-    end
 
-    def deletion_method_name(divider)
-      "no_#{DIVIDERS[divider]}"
-    end
+      attr_reader :raw_version
 
-    def define_divider_conversion_methods(left_divider)
-      (DIVIDERS.keys - [left_divider]).each do |right_divider|
-        define_divider_conversion_method(left_divider, right_divider)
+      def initialize(raw_version)
+        @raw_version = raw_version
+        super(raw_version.to_s)
       end
-    end
 
-    def define_divider_conversion_method(left_divider, right_divider)
-      method_name = conversion_method_name(left_divider, right_divider)
-      define_method(method_name) do
-        version { gsub(left_divider, right_divider) }
+      def latest?
+        to_s == "latest"
       end
-    end
 
-    def conversion_method_name(left_divider, right_divider)
-      "#{DIVIDERS[left_divider]}_to_#{DIVIDERS[right_divider]}"
-    end
-  end
-
-  DIVIDERS.keys.each do |divider|
-    define_divider_methods(divider)
-  end
-
-  attr_reader :raw_version
-
-  def initialize(raw_version)
-    @raw_version = raw_version
-    super(raw_version.to_s)
-  end
-
-  def latest?
-    to_s == "latest"
-  end
-
-  def major
-    version { slice(MAJOR_MINOR_PATCH_REGEX, 1) }
-  end
+      def major
+        version { slice(MAJOR_MINOR_PATCH_REGEX, 1) }
+      end
 
-  def minor
-    version { slice(MAJOR_MINOR_PATCH_REGEX, 2) }
-  end
+      def minor
+        version { slice(MAJOR_MINOR_PATCH_REGEX, 2) }
+      end
 
-  def patch
-    version { slice(MAJOR_MINOR_PATCH_REGEX, 3) }
-  end
+      def patch
+        version { slice(MAJOR_MINOR_PATCH_REGEX, 3) }
+      end
 
-  def major_minor
-    version { [major, minor].reject(&:empty?).join(".") }
-  end
+      def major_minor
+        version { [major, minor].reject(&:empty?).join(".") }
+      end
 
-  def major_minor_patch
-    version { [major, minor, patch].reject(&:empty?).join(".") }
-  end
+      def major_minor_patch
+        version { [major, minor, patch].reject(&:empty?).join(".") }
+      end
 
-  def before_comma
-    version { split(",", 2)[0] }
-  end
+      def before_comma
+        version { split(",", 2)[0] }
+      end
 
-  def after_comma
-    version { split(",", 2)[1] }
-  end
+      def after_comma
+        version { split(",", 2)[1] }
+      end
 
-  def before_colon
-    version { split(":", 2)[0] }
-  end
+      def before_colon
+        version { split(":", 2)[0] }
+      end
 
-  def after_colon
-    version { split(":", 2)[1] }
-  end
+      def after_colon
+        version { split(":", 2)[1] }
+      end
 
-  def no_dividers
-    version { gsub(DIVIDER_REGEX, "") }
-  end
+      def no_dividers
+        version { gsub(DIVIDER_REGEX, "") }
+      end
 
-  private
+      private
 
-  def version
-    return self if empty? || latest?
-    self.class.new(yield)
+      def version
+        return self if empty? || latest?
+        self.class.new(yield)
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/exceptions.rb b/Library/Homebrew/cask/lib/hbc/exceptions.rb
index 8813aaedf..f77106d92 100644
--- a/Library/Homebrew/cask/lib/hbc/exceptions.rb
+++ b/Library/Homebrew/cask/lib/hbc/exceptions.rb
@@ -1,146 +1,148 @@
-class Hbc::CaskError < RuntimeError; end
+module Hbc
+  class CaskError < RuntimeError; end
 
-class Hbc::AbstractCaskErrorWithToken < Hbc::CaskError
-  attr_reader :token
+  class AbstractCaskErrorWithToken < CaskError
+    attr_reader :token
 
-  def initialize(token)
-    @token = token
+    def initialize(token)
+      @token = token
+    end
   end
-end
 
-class Hbc::CaskNotInstalledError < Hbc::AbstractCaskErrorWithToken
-  def to_s
-    "#{token} is not installed"
+  class CaskNotInstalledError < AbstractCaskErrorWithToken
+    def to_s
+      "#{token} is not installed"
+    end
   end
-end
 
-class Hbc::CaskUnavailableError < Hbc::AbstractCaskErrorWithToken
-  def to_s
-    "No available Cask for #{token}"
+  class CaskUnavailableError < AbstractCaskErrorWithToken
+    def to_s
+      "No available Cask for #{token}"
+    end
   end
-end
 
-class Hbc::CaskAlreadyCreatedError < Hbc::AbstractCaskErrorWithToken
-  def to_s
-    %Q{A Cask for #{token} already exists. Run "brew cask cat #{token}" to see it.}
+  class CaskAlreadyCreatedError < AbstractCaskErrorWithToken
+    def to_s
+      %Q{A Cask for #{token} already exists. Run "brew cask cat #{token}" to see it.}
+    end
   end
-end
 
-class Hbc::CaskAlreadyInstalledError < Hbc::AbstractCaskErrorWithToken
-  def to_s
-    %Q{A Cask for #{token} is already installed. Add the "--force" option to force re-install.}
+  class CaskAlreadyInstalledError < AbstractCaskErrorWithToken
+    def to_s
+      %Q{A Cask for #{token} is already installed. Add the "--force" option to force re-install.}
+    end
   end
-end
 
-class Hbc::CaskAutoUpdatesError < Hbc::AbstractCaskErrorWithToken
-  def to_s
-    %Q{A Cask for #{token} is already installed and using auto-updates. Add the "--force" option to force re-install.}
+  class CaskAutoUpdatesError < AbstractCaskErrorWithToken
+    def to_s
+      %Q{A Cask for #{token} is already installed and using auto-updates. Add the "--force" option to force re-install.}
+    end
   end
-end
 
-class Hbc::CaskCommandFailedError < Hbc::CaskError
-  def initialize(cmd, stdout, stderr, status)
-    @cmd = cmd
-    @stdout = stdout
-    @stderr = stderr
-    @status = status
-  end
+  class CaskCommandFailedError < CaskError
+    def initialize(cmd, stdout, stderr, status)
+      @cmd = cmd
+      @stdout = stdout
+      @stderr = stderr
+      @status = status
+    end
 
-  def to_s
-    <<-EOS
-Command failed to execute!
+    def to_s
+      <<-EOS
+  Command failed to execute!
 
-==> Failed command:
-#{@cmd}
+  ==> Failed command:
+  #{@cmd}
 
-==> Standard Output of failed command:
-#{@stdout}
+  ==> Standard Output of failed command:
+  #{@stdout}
 
-==> Standard Error of failed command:
-#{@stderr}
+  ==> Standard Error of failed command:
+  #{@stderr}
 
-==> Exit status of failed command:
-#{@status.inspect}
-    EOS
+  ==> Exit status of failed command:
+  #{@status.inspect}
+      EOS
+    end
   end
-end
 
-class Hbc::CaskX11DependencyError < Hbc::AbstractCaskErrorWithToken
-  def to_s
-    <<-EOS.undent
-      #{token} requires XQuartz/X11, which can be installed via homebrew-cask by
+  class CaskX11DependencyError < AbstractCaskErrorWithToken
+    def to_s
+      <<-EOS.undent
+        #{token} requires XQuartz/X11, which can be installed via homebrew-cask by
 
-        brew cask install xquartz
+          brew cask install xquartz
 
-      or manually, by downloading the package from
+        or manually, by downloading the package from
 
-        https://www.xquartz.org/
-    EOS
+          https://www.xquartz.org/
+      EOS
+    end
   end
-end
 
-class Hbc::CaskCyclicCaskDependencyError < Hbc::AbstractCaskErrorWithToken
-  def to_s
-    "Cask '#{token}' includes cyclic dependencies on other Casks and could not be installed."
+  class CaskCyclicCaskDependencyError < AbstractCaskErrorWithToken
+    def to_s
+      "Cask '#{token}' includes cyclic dependencies on other Casks and could not be installed."
+    end
   end
-end
 
-class Hbc::CaskUnspecifiedError < Hbc::CaskError
-  def to_s
-    "This command requires a Cask token"
+  class CaskUnspecifiedError < CaskError
+    def to_s
+      "This command requires a Cask token"
+    end
   end
-end
 
-class Hbc::CaskInvalidError < Hbc::AbstractCaskErrorWithToken
-  attr_reader :submsg
-  def initialize(token, *submsg)
-    super(token)
-    @submsg = submsg.join(" ")
-  end
+  class CaskInvalidError < AbstractCaskErrorWithToken
+    attr_reader :submsg
+    def initialize(token, *submsg)
+      super(token)
+      @submsg = submsg.join(" ")
+    end
 
-  def to_s
-    "Cask '#{token}' definition is invalid" + (!submsg.empty? ? ": #{submsg}" : "")
+    def to_s
+      "Cask '#{token}' definition is invalid" + (!submsg.empty? ? ": #{submsg}" : "")
+    end
   end
-end
 
-class Hbc::CaskTokenDoesNotMatchError < Hbc::CaskInvalidError
-  def initialize(token, header_token)
-    super(token, "Bad header line: '#{header_token}' does not match file name")
+  class CaskTokenDoesNotMatchError < CaskInvalidError
+    def initialize(token, header_token)
+      super(token, "Bad header line: '#{header_token}' does not match file name")
+    end
   end
-end
 
-class Hbc::CaskSha256MissingError < ArgumentError
-end
-
-class Hbc::CaskSha256MismatchError < RuntimeError
-  attr_reader :path, :expected, :actual
-  def initialize(path, expected, actual)
-    @path = path
-    @expected = expected
-    @actual = actual
+  class CaskSha256MissingError < ArgumentError
   end
 
-  def to_s
-    <<-EOS.undent
-      sha256 mismatch
-      Expected: #{expected}
-      Actual: #{actual}
-      File: #{path}
-      To retry an incomplete download, remove the file above.
-    EOS
-  end
-end
+  class CaskSha256MismatchError < RuntimeError
+    attr_reader :path, :expected, :actual
+    def initialize(path, expected, actual)
+      @path = path
+      @expected = expected
+      @actual = actual
+    end
 
-class Hbc::CaskNoShasumError < Hbc::CaskError
-  attr_reader :token
-  def initialize(token)
-    @token = token
+    def to_s
+      <<-EOS.undent
+        sha256 mismatch
+        Expected: #{expected}
+        Actual: #{actual}
+        File: #{path}
+        To retry an incomplete download, remove the file above.
+      EOS
+    end
   end
 
-  def to_s
-    <<-EOS.undent
-      Cask '#{token}' does not have a sha256 checksum defined and was not installed.
-      This means you have the "--require-sha" option set, perhaps in your HOMEBREW_CASK_OPTS.
-    EOS
+  class CaskNoShasumError < CaskError
+    attr_reader :token
+    def initialize(token)
+      @token = token
+    end
+
+    def to_s
+      <<-EOS.undent
+        Cask '#{token}' does not have a sha256 checksum defined and was not installed.
+        This means you have the "--require-sha" option set, perhaps in your HOMEBREW_CASK_OPTS.
+      EOS
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/extend/hash.rb b/Library/Homebrew/cask/lib/hbc/extend/hash.rb
index dc28cfb29..3a06ba3af 100644
--- a/Library/Homebrew/cask/lib/hbc/extend/hash.rb
+++ b/Library/Homebrew/cask/lib/hbc/extend/hash.rb
@@ -2,6 +2,6 @@ class Hash
   def assert_valid_keys(*valid_keys)
     unknown_keys = keys - valid_keys
     return if unknown_keys.empty?
-    raise Hbc::CaskError, %Q{Unknown keys: #{unknown_keys.inspect}. Running "#{UPDATE_CMD}" will likely fix it.}
+    raise CaskError, %Q{Unknown keys: #{unknown_keys.inspect}. Running "#{UPDATE_CMD}" will likely fix it.}
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/fetcher.rb b/Library/Homebrew/cask/lib/hbc/fetcher.rb
index 44a898ce0..6f58ca023 100644
--- a/Library/Homebrew/cask/lib/hbc/fetcher.rb
+++ b/Library/Homebrew/cask/lib/hbc/fetcher.rb
@@ -1,22 +1,24 @@
 require "open3"
 
-class Hbc::Fetcher
-  TIMEOUT = 10
+module Hbc
+  class Fetcher
+    TIMEOUT = 10
 
-  def self.head(url)
-    if url.to_s =~ %r{googlecode}
-      googlecode_fake_head(url)
-    else
-      Hbc::SystemCommand.run("/usr/bin/curl",
-                             args: ["--max-time", TIMEOUT, "--silent", "--location", "--head", url]).stdout
+    def self.head(url)
+      if url.to_s =~ %r{googlecode}
+        googlecode_fake_head(url)
+      else
+        SystemCommand.run("/usr/bin/curl",
+                          args: ["--max-time", TIMEOUT, "--silent", "--location", "--head", url]).stdout
+      end
     end
-  end
 
-  # google code does not properly respond to HTTP HEAD requests, like a jerk
-  # this fakes a HEAD by doing a GET, taking the first 20 lines, then running away
-  def self.googlecode_fake_head(url)
-    command = "curl --max-time #{TIMEOUT} --verbose --location '#{url}' | head -n 20 > /dev/null"
-    stderr = Open3.capture3(command)[1]
-    stderr.split("\n").grep(%r{^< }).map { |line| line.sub(%r{^< }, "") }.join("\n")
+    # google code does not properly respond to HTTP HEAD requests, like a jerk
+    # this fakes a HEAD by doing a GET, taking the first 20 lines, then running away
+    def self.googlecode_fake_head(url)
+      command = "curl --max-time #{TIMEOUT} --verbose --location '#{url}' | head -n 20 > /dev/null"
+      stderr = Open3.capture3(command)[1]
+      stderr.split("\n").grep(%r{^< }).map { |line| line.sub(%r{^< }, "") }.join("\n")
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/installer.rb b/Library/Homebrew/cask/lib/hbc/installer.rb
index 72a9b3077..f0cc0d1a9 100644
--- a/Library/Homebrew/cask/lib/hbc/installer.rb
+++ b/Library/Homebrew/cask/lib/hbc/installer.rb
@@ -4,142 +4,144 @@ require "hbc/cask_dependencies"
 require "hbc/staged"
 require "hbc/verify"
 
-class Hbc::Installer
-  # TODO: it is unwise for Hbc::Staged to be a module, when we are
-  #       dealing with both staged and unstaged Casks here.  This should
-  #       either be a class which is only sometimes instantiated, or there
-  #       should be explicit checks on whether staged state is valid in
-  #       every method.
-  include Hbc::Staged
-  include Hbc::Verify
-
-  attr_reader :force, :skip_cask_deps
-
-  PERSISTENT_METADATA_SUBDIRS = ["gpg"].freeze
-
-  def initialize(cask, command: Hbc::SystemCommand, force: false, skip_cask_deps: false, require_sha: false)
-    @cask = cask
-    @command = command
-    @force = force
-    @skip_cask_deps = skip_cask_deps
-    @require_sha = require_sha
-  end
+module Hbc
+  class Installer
+    # TODO: it is unwise for Hbc::Staged to be a module, when we are
+    #       dealing with both staged and unstaged Casks here. This should
+    #       either be a class which is only sometimes instantiated, or there
+    #       should be explicit checks on whether staged state is valid in
+    #       every method.
+    include Staged
+    include Verify
+
+    attr_reader :force, :skip_cask_deps
+
+    PERSISTENT_METADATA_SUBDIRS = ["gpg"].freeze
+
+    def initialize(cask, command: SystemCommand, force: false, skip_cask_deps: false, require_sha: false)
+      @cask = cask
+      @command = command
+      @force = force
+      @skip_cask_deps = skip_cask_deps
+      @require_sha = require_sha
+    end
 
-  def self.print_caveats(cask)
-    odebug "Printing caveats"
-    unless cask.caveats.empty?
-      output = capture_output do
-        cask.caveats.each do |caveat|
-          if caveat.respond_to?(:eval_and_print)
-            caveat.eval_and_print(cask)
-          else
-            puts caveat
+    def self.print_caveats(cask)
+      odebug "Printing caveats"
+      unless cask.caveats.empty?
+        output = capture_output do
+          cask.caveats.each do |caveat|
+            if caveat.respond_to?(:eval_and_print)
+              caveat.eval_and_print(cask)
+            else
+              puts caveat
+            end
           end
         end
-      end
 
-      unless output.empty?
-        ohai "Caveats"
-        puts output
+        unless output.empty?
+          ohai "Caveats"
+          puts output
+        end
       end
     end
-  end
-
-  def self.capture_output(&block)
-    old_stdout = $stdout
-    $stdout = Buffer.new($stdout.tty?)
-    block.call
-    output = $stdout.string
-    $stdout = old_stdout
-    output
-  end
 
-  def install
-    odebug "Hbc::Installer.install"
-
-    if @cask.installed? && @cask.auto_updates && !force
-      raise Hbc::CaskAutoUpdatesError, @cask
+    def self.capture_output(&block)
+      old_stdout = $stdout
+      $stdout = Buffer.new($stdout.tty?)
+      block.call
+      output = $stdout.string
+      $stdout = old_stdout
+      output
     end
 
-    raise Hbc::CaskAlreadyInstalledError, @cask if @cask.installed? && !force
+    def install
+      odebug "Hbc::Installer.install"
+
+      if @cask.installed? && @cask.auto_updates && !force
+        raise CaskAutoUpdatesError, @cask
+      end
 
-    print_caveats
+      raise CaskAlreadyInstalledError, @cask if @cask.installed? && !force
+
+      print_caveats
+
+      begin
+        satisfy_dependencies
+        verify_has_sha if @require_sha && !@force
+        download
+        verify
+        extract_primary_container
+        install_artifacts
+        save_caskfile
+        enable_accessibility_access
+      rescue StandardError => e
+        purge_versioned_files
+        raise e
+      end
 
-    begin
-      satisfy_dependencies
-      verify_has_sha if @require_sha && !@force
-      download
-      verify
-      extract_primary_container
-      install_artifacts
-      save_caskfile
-      enable_accessibility_access
-    rescue StandardError => e
-      purge_versioned_files
-      raise e
+      puts summary
     end
 
-    puts summary
-  end
-
-  def summary
-    s = if MacOS.version >= :lion && !ENV["HOMEBREW_NO_EMOJI"]
-          (ENV["HOMEBREW_INSTALL_BADGE"] || "\xf0\x9f\x8d\xba") + "  "
-        else
-          "#{Tty.blue}==>#{Tty.reset} #{Tty.white}Success!#{Tty.reset} "
-        end
-    s << "#{@cask} was successfully installed!"
-  end
+    def summary
+      s = if MacOS.version >= :lion && !ENV["HOMEBREW_NO_EMOJI"]
+            (ENV["HOMEBREW_INSTALL_BADGE"] || "\xf0\x9f\x8d\xba") + "  "
+          else
+            "#{Tty.blue}==>#{Tty.reset} #{Tty.white}Success!#{Tty.reset} "
+          end
+      s << "#{@cask} was successfully installed!"
+    end
 
-  def download
-    odebug "Downloading"
-    download = Hbc::Download.new(@cask, force: false)
-    @downloaded_path = download.perform
-    odebug "Downloaded to -> #{@downloaded_path}"
-    @downloaded_path
-  end
+    def download
+      odebug "Downloading"
+      download = Download.new(@cask, force: false)
+      @downloaded_path = download.perform
+      odebug "Downloaded to -> #{@downloaded_path}"
+      @downloaded_path
+    end
 
-  def verify_has_sha
-    odebug "Checking cask has checksum"
-    return unless @cask.sha256 == :no_check
-    raise Hbc::CaskNoShasumError, @cask
-  end
+    def verify_has_sha
+      odebug "Checking cask has checksum"
+      return unless @cask.sha256 == :no_check
+      raise CaskNoShasumError, @cask
+    end
 
-  def verify
-    Hbc::Verify.all(@cask, @downloaded_path)
-  end
+    def verify
+      Verify.all(@cask, @downloaded_path)
+    end
 
-  def extract_primary_container
-    odebug "Extracting primary container"
-    FileUtils.mkdir_p @cask.staged_path
-    container = if @cask.container && @cask.container.type
-                  Hbc::Container.from_type(@cask.container.type)
-                else
-                  Hbc::Container.for_path(@downloaded_path, @command)
-                end
-    unless container
-      raise Hbc::CaskError, "Uh oh, could not figure out how to unpack '#{@downloaded_path}'"
+    def extract_primary_container
+      odebug "Extracting primary container"
+      FileUtils.mkdir_p @cask.staged_path
+      container = if @cask.container && @cask.container.type
+                    Container.from_type(@cask.container.type)
+                  else
+                    Container.for_path(@downloaded_path, @command)
+                  end
+      unless container
+        raise CaskError, "Uh oh, could not figure out how to unpack '#{@downloaded_path}'"
+      end
+      odebug "Using container class #{container} for #{@downloaded_path}"
+      container.new(@cask, @downloaded_path, @command).extract
     end
-    odebug "Using container class #{container} for #{@downloaded_path}"
-    container.new(@cask, @downloaded_path, @command).extract
-  end
 
-  def install_artifacts
-    odebug "Installing artifacts"
-    artifacts = Hbc::Artifact.for_cask(@cask)
-    odebug "#{artifacts.length} artifact/s defined", artifacts
-    artifacts.each do |artifact|
-      odebug "Installing artifact of class #{artifact}"
-      options = { command: @command, force: force }
-      artifact.new(@cask, options).install_phase
+    def install_artifacts
+      odebug "Installing artifacts"
+      artifacts = Artifact.for_cask(@cask)
+      odebug "#{artifacts.length} artifact/s defined", artifacts
+      artifacts.each do |artifact|
+        odebug "Installing artifact of class #{artifact}"
+        options = { command: @command, force: force }
+        artifact.new(@cask, options).install_phase
+      end
     end
-  end
 
-  # TODO: move dependencies to a separate class
-  #       dependencies should also apply for "brew cask stage"
-  #       override dependencies with --force or perhaps --force-deps
-  def satisfy_dependencies
-    if @cask.depends_on
+    # TODO: move dependencies to a separate class
+    #       dependencies should also apply for "brew cask stage"
+    #       override dependencies with --force or perhaps --force-deps
+    def satisfy_dependencies
+      return unless @cask.depends_on
+
       ohai "Satisfying dependencies"
       macos_dependencies
       arch_dependencies
@@ -148,195 +150,200 @@ class Hbc::Installer
       cask_dependencies unless skip_cask_deps
       puts "complete"
     end
-  end
 
-  def macos_dependencies
-    return unless @cask.depends_on.macos
-    if @cask.depends_on.macos.first.is_a?(Array)
-      operator, release = @cask.depends_on.macos.first
-      unless MacOS.version.send(operator, release)
-        raise Hbc::CaskError, "Cask #{@cask} depends on macOS release #{operator} #{release}, but you are running release #{MacOS.version}."
-      end
-    elsif @cask.depends_on.macos.length > 1
-      unless @cask.depends_on.macos.include?(Gem::Version.new(MacOS.version.to_s))
-        raise Hbc::CaskError, "Cask #{@cask} depends on macOS release being one of [#{@cask.depends_on.macos.map(&:to_s).join(', ')}], but you are running release #{MacOS.version}."
-      end
-    else
-      unless MacOS.version == @cask.depends_on.macos.first
-        raise Hbc::CaskError, "Cask #{@cask} depends on macOS release #{@cask.depends_on.macos.first}, but you are running release #{MacOS.version}."
+    def macos_dependencies
+      return unless @cask.depends_on.macos
+      if @cask.depends_on.macos.first.is_a?(Array)
+        operator, release = @cask.depends_on.macos.first
+        unless MacOS.version.send(operator, release)
+          raise CaskError, "Cask #{@cask} depends on macOS release #{operator} #{release}, but you are running release #{MacOS.version}."
+        end
+      elsif @cask.depends_on.macos.length > 1
+        unless @cask.depends_on.macos.include?(Gem::Version.new(MacOS.version.to_s))
+          raise CaskError, "Cask #{@cask} depends on macOS release being one of [#{@cask.depends_on.macos.map(&:to_s).join(", ")}], but you are running release #{MacOS.version}."
+        end
+      else
+        unless MacOS.version == @cask.depends_on.macos.first
+          raise CaskError, "Cask #{@cask} depends on macOS release #{@cask.depends_on.macos.first}, but you are running release #{MacOS.version}."
+        end
       end
     end
-  end
 
-  def arch_dependencies
-    return if @cask.depends_on.arch.nil?
-    @current_arch ||= { type: Hardware::CPU.type, bits: Hardware::CPU.bits }
-    return if @cask.depends_on.arch.any? { |arch|
-      arch[:type] == @current_arch[:type] &&
-      Array(arch[:bits]).include?(@current_arch[:bits])
-    }
-    raise Hbc::CaskError, "Cask #{@cask} depends on hardware architecture being one of [#{@cask.depends_on.arch.map(&:to_s).join(', ')}], but you are running #{@current_arch}"
-  end
+    def arch_dependencies
+      return if @cask.depends_on.arch.nil?
+      @current_arch ||= { type: Hardware::CPU.type, bits: Hardware::CPU.bits }
+      return if @cask.depends_on.arch.any? { |arch|
+        arch[:type] == @current_arch[:type] &&
+        Array(arch[:bits]).include?(@current_arch[:bits])
+      }
+      raise CaskError, "Cask #{@cask} depends on hardware architecture being one of [#{@cask.depends_on.arch.map(&:to_s).join(", ")}], but you are running #{@current_arch}"
+    end
 
-  def x11_dependencies
-    return unless @cask.depends_on.x11
-    raise Hbc::CaskX11DependencyError, @cask.token if Hbc.x11_libpng.select(&:exist?).empty?
-  end
+    def x11_dependencies
+      return unless @cask.depends_on.x11
+      raise CaskX11DependencyError, @cask.token if Hbc.x11_libpng.select(&:exist?).empty?
+    end
 
-  def formula_dependencies
-    return unless @cask.depends_on.formula && !@cask.depends_on.formula.empty?
-    ohai "Installing Formula dependencies from Homebrew"
-    @cask.depends_on.formula.each do |dep_name|
-      print "#{dep_name} ... "
-      installed = @command.run(Hbc.homebrew_executable,
-                               args:         ["list", "--versions", dep_name],
-                               print_stderr: false).stdout.include?(dep_name)
-      if installed
-        puts "already installed"
-      else
-        @command.run!(Hbc.homebrew_executable,
-                      args: ["install", dep_name])
-        puts "done"
+    def formula_dependencies
+      return unless @cask.depends_on.formula && !@cask.depends_on.formula.empty?
+      ohai "Installing Formula dependencies from Homebrew"
+      @cask.depends_on.formula.each do |dep_name|
+        print "#{dep_name} ... "
+        installed = @command.run(Hbc.homebrew_executable,
+                                 args:         ["list", "--versions", dep_name],
+                                 print_stderr: false).stdout.include?(dep_name)
+        if installed
+          puts "already installed"
+        else
+          @command.run!(Hbc.homebrew_executable,
+                        args: ["install", dep_name])
+          puts "done"
+        end
       end
     end
-  end
 
-  def cask_dependencies
-    return unless @cask.depends_on.cask && !@cask.depends_on.cask.empty?
-    ohai "Installing Cask dependencies: #{@cask.depends_on.cask.join(', ')}"
-    deps = Hbc::CaskDependencies.new(@cask)
-    deps.sorted.each do |dep_token|
-      puts "#{dep_token} ..."
-      dep = Hbc.load(dep_token)
-      if dep.installed?
-        puts "already installed"
-      else
-        Hbc::Installer.new(dep, force: false, skip_cask_deps: true).install
-        puts "done"
+    def cask_dependencies
+      return unless @cask.depends_on.cask && !@cask.depends_on.cask.empty?
+      ohai "Installing Cask dependencies: #{@cask.depends_on.cask.join(", ")}"
+      deps = CaskDependencies.new(@cask)
+      deps.sorted.each do |dep_token|
+        puts "#{dep_token} ..."
+        dep = Hbc.load(dep_token)
+        if dep.installed?
+          puts "already installed"
+        else
+          Installer.new(dep, force: false, skip_cask_deps: true).install
+          puts "done"
+        end
       end
     end
-  end
 
-  def print_caveats
-    self.class.print_caveats(@cask)
-  end
+    def print_caveats
+      self.class.print_caveats(@cask)
+    end
 
-  # TODO: logically could be in a separate class
-  def enable_accessibility_access
-    return unless @cask.accessibility_access
-    ohai "Enabling accessibility access"
-    if MacOS.version <= :mountain_lion
-      @command.run!("/usr/bin/touch",
-                    args: [Hbc.pre_mavericks_accessibility_dotfile],
-                    sudo: true)
-    elsif MacOS.version <= :yosemite
-      @command.run!("/usr/bin/sqlite3",
-                    args: [
-                            Hbc.tcc_db,
-                            "INSERT OR REPLACE INTO access VALUES('kTCCServiceAccessibility','#{bundle_identifier}',0,1,1,NULL);",
-                          ],
-                    sudo: true)
-    else
-      @command.run!("/usr/bin/sqlite3",
-                    args: [
-                            Hbc.tcc_db,
-                            "INSERT OR REPLACE INTO access VALUES('kTCCServiceAccessibility','#{bundle_identifier}',0,1,1,NULL,NULL);",
-                          ],
-                    sudo: true)
+    # TODO: logically could be in a separate class
+    def enable_accessibility_access
+      return unless @cask.accessibility_access
+      ohai "Enabling accessibility access"
+      if MacOS.version <= :mountain_lion
+        @command.run!("/usr/bin/touch",
+                      args: [Hbc.pre_mavericks_accessibility_dotfile],
+                      sudo: true)
+      elsif MacOS.version <= :yosemite
+        @command.run!("/usr/bin/sqlite3",
+                      args: [
+                              Hbc.tcc_db,
+                              "INSERT OR REPLACE INTO access VALUES('kTCCServiceAccessibility','#{bundle_identifier}',0,1,1,NULL);",
+                            ],
+                      sudo: true)
+      elsif MacOS.version <= :el_capitan
+        @command.run!("/usr/bin/sqlite3",
+                      args: [
+                              Hbc.tcc_db,
+                              "INSERT OR REPLACE INTO access VALUES('kTCCServiceAccessibility','#{bundle_identifier}',0,1,1,NULL,NULL);",
+                            ],
+                      sudo: true)
+      else
+        opoo <<-EOS.undent
+          Accessibility access cannot be enabled automatically on this version of macOS.
+          See System Preferences to enable it manually.
+        EOS
+      end
     end
-  end
 
-  def disable_accessibility_access
-    return unless @cask.accessibility_access
-    if MacOS.version >= :mavericks
-      ohai "Disabling accessibility access"
-      @command.run!("/usr/bin/sqlite3",
-                    args: [
-                            Hbc.tcc_db,
-                            "DELETE FROM access WHERE client='#{bundle_identifier}';",
-                          ],
-                    sudo: true)
-    else
-      opoo <<-EOS.undent
-        Accessibility access was enabled for #{@cask}, but it is not safe to disable
-        automatically on this version of macOS.  See System Preferences.
-      EOS
+    def disable_accessibility_access
+      return unless @cask.accessibility_access
+      if MacOS.version >= :mavericks && MacOS.version <= :el_capitan
+        ohai "Disabling accessibility access"
+        @command.run!("/usr/bin/sqlite3",
+                      args: [
+                              Hbc.tcc_db,
+                              "DELETE FROM access WHERE client='#{bundle_identifier}';",
+                            ],
+                      sudo: true)
+      else
+        opoo <<-EOS.undent
+          Accessibility access cannot be disabled automatically on this version of macOS.
+          See System Preferences to disable it manually.
+        EOS
+      end
     end
-  end
 
-  def save_caskfile
-    timestamp = :now
-    create    = true
-    savedir   = @cask.metadata_subdir("Casks", timestamp, create)
-    if Dir.entries(savedir).size > 2
-      # should not happen
-      raise Hbc::CaskAlreadyInstalledError, @cask unless force
-      savedir.rmtree
-      FileUtils.mkdir_p savedir
+    def save_caskfile
+      timestamp = :now
+      create    = true
+      savedir   = @cask.metadata_subdir("Casks", timestamp, create)
+      if Dir.entries(savedir).size > 2
+        # should not happen
+        raise CaskAlreadyInstalledError, @cask unless force
+        savedir.rmtree
+        FileUtils.mkdir_p savedir
+      end
+      FileUtils.copy(@cask.sourcefile_path, savedir) if @cask.sourcefile_path
     end
-    FileUtils.copy(@cask.sourcefile_path, savedir) if @cask.sourcefile_path
-  end
 
-  def uninstall
-    odebug "Hbc::Installer.uninstall"
-    disable_accessibility_access
-    uninstall_artifacts
-    purge_versioned_files
-    purge_caskroom_path if force
-  end
+    def uninstall
+      odebug "Hbc::Installer.uninstall"
+      disable_accessibility_access
+      uninstall_artifacts
+      purge_versioned_files
+      purge_caskroom_path if force
+    end
 
-  def uninstall_artifacts
-    odebug "Un-installing artifacts"
-    artifacts = Hbc::Artifact.for_cask(@cask)
-    odebug "#{artifacts.length} artifact/s defined", artifacts
-    artifacts.each do |artifact|
-      odebug "Un-installing artifact of class #{artifact}"
-      options = { command: @command, force: force }
-      artifact.new(@cask, options).uninstall_phase
+    def uninstall_artifacts
+      odebug "Un-installing artifacts"
+      artifacts = Artifact.for_cask(@cask)
+      odebug "#{artifacts.length} artifact/s defined", artifacts
+      artifacts.each do |artifact|
+        odebug "Un-installing artifact of class #{artifact}"
+        options = { command: @command, force: force }
+        artifact.new(@cask, options).uninstall_phase
+      end
     end
-  end
 
-  def zap
-    ohai %Q{Implied "brew cask uninstall #{@cask}"}
-    uninstall_artifacts
-    if Hbc::Artifact::Zap.me?(@cask)
-      ohai "Dispatching zap stanza"
-      Hbc::Artifact::Zap.new(@cask, command: @command).zap_phase
-    else
-      opoo "No zap stanza present for Cask '#{@cask}'"
+    def zap
+      ohai %Q{Implied "brew cask uninstall #{@cask}"}
+      uninstall_artifacts
+      if Artifact::Zap.me?(@cask)
+        ohai "Dispatching zap stanza"
+        Artifact::Zap.new(@cask, command: @command).zap_phase
+      else
+        opoo "No zap stanza present for Cask '#{@cask}'"
+      end
+      ohai "Removing all staged versions of Cask '#{@cask}'"
+      purge_caskroom_path
     end
-    ohai "Removing all staged versions of Cask '#{@cask}'"
-    purge_caskroom_path
-  end
 
-  def gain_permissions_remove(path)
-    Hbc::Utils.gain_permissions_remove(path, command: @command)
-  end
+    def gain_permissions_remove(path)
+      Utils.gain_permissions_remove(path, command: @command)
+    end
 
-  def purge_versioned_files
-    odebug "Purging files for version #{@cask.version} of Cask #{@cask}"
+    def purge_versioned_files
+      odebug "Purging files for version #{@cask.version} of Cask #{@cask}"
 
-    # versioned staged distribution
-    gain_permissions_remove(@cask.staged_path) if !@cask.staged_path.nil? && @cask.staged_path.exist?
+      # versioned staged distribution
+      gain_permissions_remove(@cask.staged_path) if !@cask.staged_path.nil? && @cask.staged_path.exist?
 
-    # Homebrew-Cask metadata
-    if @cask.metadata_versioned_container_path.respond_to?(:children) &&
-       @cask.metadata_versioned_container_path.exist?
-      @cask.metadata_versioned_container_path.children.each do |subdir|
-        unless PERSISTENT_METADATA_SUBDIRS.include?(subdir.basename)
-          gain_permissions_remove(subdir)
+      # Homebrew-Cask metadata
+      if @cask.metadata_versioned_container_path.respond_to?(:children) &&
+         @cask.metadata_versioned_container_path.exist?
+        @cask.metadata_versioned_container_path.children.each do |subdir|
+          unless PERSISTENT_METADATA_SUBDIRS.include?(subdir.basename)
+            gain_permissions_remove(subdir)
+          end
         end
       end
-    end
-    @cask.metadata_versioned_container_path.rmdir_if_possible
-    @cask.metadata_master_container_path.rmdir_if_possible
+      @cask.metadata_versioned_container_path.rmdir_if_possible
+      @cask.metadata_master_container_path.rmdir_if_possible
 
-    # toplevel staged distribution
-    @cask.caskroom_path.rmdir_if_possible
-  end
+      # toplevel staged distribution
+      @cask.caskroom_path.rmdir_if_possible
+    end
 
-  def purge_caskroom_path
-    odebug "Purging all staged versions of Cask #{@cask}"
-    gain_permissions_remove(@cask.caskroom_path)
+    def purge_caskroom_path
+      odebug "Purging all staged versions of Cask #{@cask}"
+      gain_permissions_remove(@cask.caskroom_path)
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/locations.rb b/Library/Homebrew/cask/lib/hbc/locations.rb
index 5e18ba8fe..32c95413c 100644
--- a/Library/Homebrew/cask/lib/hbc/locations.rb
+++ b/Library/Homebrew/cask/lib/hbc/locations.rb
@@ -1,196 +1,198 @@
-module Hbc::Locations
-  def self.included(base)
-    base.extend(ClassMethods)
-  end
-
-  module ClassMethods
-    def legacy_caskroom
-      @legacy_caskroom ||= Pathname.new("/opt/homebrew-cask/Caskroom")
+module Hbc
+  module Locations
+    def self.included(base)
+      base.extend(ClassMethods)
     end
 
-    def default_caskroom
-      @default_caskroom ||= homebrew_prefix.join("Caskroom")
-    end
+    module ClassMethods
+      def legacy_caskroom
+        @legacy_caskroom ||= Pathname.new("/opt/homebrew-cask/Caskroom")
+      end
 
-    def caskroom
-      @caskroom ||= begin
-        if Hbc::Utils.path_occupied?(legacy_caskroom)
-          opoo <<-EOS.undent
-            The default Caskroom location has moved to #{default_caskroom}.
+      def default_caskroom
+        @default_caskroom ||= homebrew_prefix.join("Caskroom")
+      end
 
-            Please migrate your Casks to the new location and delete #{legacy_caskroom},
-            or if you would like to keep your Caskroom at #{legacy_caskroom}, add the
-            following to your HOMEBREW_CASK_OPTS:
+      def caskroom
+        @caskroom ||= begin
+          if Utils.path_occupied?(legacy_caskroom)
+            opoo <<-EOS.undent
+              The default Caskroom location has moved to #{default_caskroom}.
 
-              --caskroom=#{legacy_caskroom}
+              Please migrate your Casks to the new location and delete #{legacy_caskroom},
+              or if you would like to keep your Caskroom at #{legacy_caskroom}, add the
+              following to your HOMEBREW_CASK_OPTS:
 
-            For more details on each of those options, see https://github.com/caskroom/homebrew-cask/issues/21913.
-          EOS
-          legacy_caskroom
-        else
-          default_caskroom
+                --caskroom=#{legacy_caskroom}
+
+              For more details on each of those options, see https://github.com/caskroom/homebrew-cask/issues/21913.
+            EOS
+            legacy_caskroom
+          else
+            default_caskroom
+          end
         end
       end
-    end
 
-    def caskroom=(caskroom)
-      @caskroom = caskroom
-    end
+      def caskroom=(caskroom)
+        @caskroom = caskroom
+      end
 
-    def legacy_cache
-      @legacy_cache ||= homebrew_cache.join("Casks")
-    end
+      def legacy_cache
+        @legacy_cache ||= homebrew_cache.join("Casks")
+      end
 
-    def cache
-      @cache ||= homebrew_cache.join("Cask")
-    end
+      def cache
+        @cache ||= homebrew_cache.join("Cask")
+      end
 
-    attr_writer :appdir
+      attr_writer :appdir
 
-    def appdir
-      @appdir ||= Pathname.new("/Applications").expand_path
-    end
+      def appdir
+        @appdir ||= Pathname.new("/Applications").expand_path
+      end
 
-    attr_writer :prefpanedir
+      attr_writer :prefpanedir
 
-    def prefpanedir
-      @prefpanedir ||= Pathname.new("~/Library/PreferencePanes").expand_path
-    end
+      def prefpanedir
+        @prefpanedir ||= Pathname.new("~/Library/PreferencePanes").expand_path
+      end
 
-    attr_writer :qlplugindir
+      attr_writer :qlplugindir
 
-    def qlplugindir
-      @qlplugindir ||= Pathname.new("~/Library/QuickLook").expand_path
-    end
+      def qlplugindir
+        @qlplugindir ||= Pathname.new("~/Library/QuickLook").expand_path
+      end
 
-    attr_writer :fontdir
+      attr_writer :fontdir
 
-    def fontdir
-      @fontdir ||= Pathname.new("~/Library/Fonts").expand_path
-    end
+      def fontdir
+        @fontdir ||= Pathname.new("~/Library/Fonts").expand_path
+      end
 
-    attr_writer :colorpickerdir
+      attr_writer :colorpickerdir
 
-    def colorpickerdir
-      @colorpickerdir ||= Pathname.new("~/Library/ColorPickers").expand_path
-    end
+      def colorpickerdir
+        @colorpickerdir ||= Pathname.new("~/Library/ColorPickers").expand_path
+      end
 
-    attr_writer :servicedir
+      attr_writer :servicedir
 
-    def servicedir
-      @servicedir ||= Pathname.new("~/Library/Services").expand_path
-    end
+      def servicedir
+        @servicedir ||= Pathname.new("~/Library/Services").expand_path
+      end
 
-    attr_writer :binarydir
+      attr_writer :binarydir
 
-    def binarydir
-      @binarydir ||= homebrew_prefix.join("bin")
-    end
+      def binarydir
+        @binarydir ||= homebrew_prefix.join("bin")
+      end
 
-    attr_writer :input_methoddir
+      attr_writer :input_methoddir
 
-    def input_methoddir
-      @input_methoddir ||= Pathname.new("~/Library/Input Methods").expand_path
-    end
+      def input_methoddir
+        @input_methoddir ||= Pathname.new("~/Library/Input Methods").expand_path
+      end
 
-    attr_writer :internet_plugindir
+      attr_writer :internet_plugindir
 
-    def internet_plugindir
-      @internet_plugindir ||= Pathname.new("~/Library/Internet Plug-Ins").expand_path
-    end
+      def internet_plugindir
+        @internet_plugindir ||= Pathname.new("~/Library/Internet Plug-Ins").expand_path
+      end
 
-    attr_writer :audio_unit_plugindir
+      attr_writer :audio_unit_plugindir
 
-    def audio_unit_plugindir
-      @audio_unit_plugindir ||= Pathname.new("~/Library/Audio/Plug-Ins/Components").expand_path
-    end
+      def audio_unit_plugindir
+        @audio_unit_plugindir ||= Pathname.new("~/Library/Audio/Plug-Ins/Components").expand_path
+      end
 
-    attr_writer :vst_plugindir
+      attr_writer :vst_plugindir
 
-    def vst_plugindir
-      @vst_plugindir ||= Pathname.new("~/Library/Audio/Plug-Ins/VST").expand_path
-    end
+      def vst_plugindir
+        @vst_plugindir ||= Pathname.new("~/Library/Audio/Plug-Ins/VST").expand_path
+      end
 
-    attr_writer :vst3_plugindir
+      attr_writer :vst3_plugindir
 
-    def vst3_plugindir
-      @vst3_plugindir ||= Pathname.new("~/Library/Audio/Plug-Ins/VST3").expand_path
-    end
+      def vst3_plugindir
+        @vst3_plugindir ||= Pathname.new("~/Library/Audio/Plug-Ins/VST3").expand_path
+      end
 
-    attr_writer :screen_saverdir
+      attr_writer :screen_saverdir
 
-    def screen_saverdir
-      @screen_saverdir ||= Pathname.new("~/Library/Screen Savers").expand_path
-    end
+      def screen_saverdir
+        @screen_saverdir ||= Pathname.new("~/Library/Screen Savers").expand_path
+      end
 
-    attr_writer :default_tap
+      attr_writer :default_tap
 
-    def default_tap
-      @default_tap ||= Tap.fetch("caskroom", "homebrew-cask")
-    end
+      def default_tap
+        @default_tap ||= Tap.fetch("caskroom", "homebrew-cask")
+      end
 
-    def path(query)
-      query = query.sub(%r{\.rb$}i, "")
-      token_with_tap = if query.include?("/")
-                         query
-                       else
-                         all_tokens.detect do |tap_and_token|
-                           tap_and_token.split("/")[2] == query
+      def path(query)
+        query = query.sub(%r{\.rb$}i, "")
+        token_with_tap = if query.include?("/")
+                           query
+                         else
+                           all_tokens.detect do |tap_and_token|
+                             tap_and_token.split("/")[2] == query
+                           end
                          end
-                       end
 
-      if token_with_tap
-        user, repo, token = token_with_tap.split("/")
-        Tap.fetch(user, repo).cask_dir.join("#{token}.rb")
-      else
-        default_tap.cask_dir.join("#{query}.rb")
+        if token_with_tap
+          user, repo, token = token_with_tap.split("/")
+          Tap.fetch(user, repo).cask_dir.join("#{token}.rb")
+        else
+          default_tap.cask_dir.join("#{query}.rb")
+        end
       end
-    end
 
-    def tcc_db
-      @tcc_db ||= Pathname.new("/Library/Application Support/com.apple.TCC/TCC.db")
-    end
+      def tcc_db
+        @tcc_db ||= Pathname.new("/Library/Application Support/com.apple.TCC/TCC.db")
+      end
 
-    def pre_mavericks_accessibility_dotfile
-      @pre_mavericks_accessibility_dotfile ||= Pathname.new("/private/var/db/.AccessibilityAPIEnabled")
-    end
+      def pre_mavericks_accessibility_dotfile
+        @pre_mavericks_accessibility_dotfile ||= Pathname.new("/private/var/db/.AccessibilityAPIEnabled")
+      end
 
-    def x11_executable
-      @x11_executable ||= Pathname.new("/usr/X11/bin/X")
-    end
+      def x11_executable
+        @x11_executable ||= Pathname.new("/usr/X11/bin/X")
+      end
 
-    def x11_libpng
-      @x11_libpng ||= [Pathname.new("/opt/X11/lib/libpng.dylib"), Pathname.new("/usr/X11/lib/libpng.dylib")]
-    end
+      def x11_libpng
+        @x11_libpng ||= [Pathname.new("/opt/X11/lib/libpng.dylib"), Pathname.new("/usr/X11/lib/libpng.dylib")]
+      end
 
-    def homebrew_cache
-      @homebrew_cache ||= HOMEBREW_CACHE
-    end
+      def homebrew_cache
+        @homebrew_cache ||= HOMEBREW_CACHE
+      end
 
-    def homebrew_cache=(path)
-      @homebrew_cache = path ? Pathname.new(path) : path
-    end
+      def homebrew_cache=(path)
+        @homebrew_cache = path ? Pathname.new(path) : path
+      end
 
-    def homebrew_executable
-      @homebrew_executable ||= HOMEBREW_BREW_FILE
-    end
+      def homebrew_executable
+        @homebrew_executable ||= HOMEBREW_BREW_FILE
+      end
 
-    def homebrew_prefix
-      # where Homebrew links
-      @homebrew_prefix ||= HOMEBREW_PREFIX
-    end
+      def homebrew_prefix
+        # where Homebrew links
+        @homebrew_prefix ||= HOMEBREW_PREFIX
+      end
 
-    def homebrew_prefix=(path)
-      @homebrew_prefix = path ? Pathname.new(path) : path
-    end
+      def homebrew_prefix=(path)
+        @homebrew_prefix = path ? Pathname.new(path) : path
+      end
 
-    def homebrew_repository
-      # where Homebrew's .git dir is found
-      @homebrew_repository ||= HOMEBREW_REPOSITORY
-    end
+      def homebrew_repository
+        # where Homebrew's .git dir is found
+        @homebrew_repository ||= HOMEBREW_REPOSITORY
+      end
 
-    def homebrew_repository=(path)
-      @homebrew_repository = path ? Pathname.new(path) : path
+      def homebrew_repository=(path)
+        @homebrew_repository = path ? Pathname.new(path) : path
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/macos.rb b/Library/Homebrew/cask/lib/hbc/macos.rb
index 5e25c657e..fb15be108 100644
--- a/Library/Homebrew/cask/lib/hbc/macos.rb
+++ b/Library/Homebrew/cask/lib/hbc/macos.rb
@@ -2,377 +2,377 @@ require "set"
 
 require "os/mac/version"
 
-module OS::Mac
-  SYSTEM_DIRS = [
-                  "/",
-                  "/Applications",
-                  "/Applications/Utilities",
-                  "/Incompatible Software",
-                  "/Library",
-                  "/Library/Application Support",
-                  "/Library/Audio",
-                  "/Library/Caches",
-                  "/Library/ColorPickers",
-                  "/Library/ColorSync",
-                  "/Library/Components",
-                  "/Library/Compositions",
-                  "/Library/Contextual Menu Items",
-                  "/Library/CoreMediaIO",
-                  "/Library/Desktop Pictures",
-                  "/Library/Developer",
-                  "/Library/Dictionaries",
-                  "/Library/DirectoryServices",
-                  "/Library/Documentation",
-                  "/Library/Extensions",
-                  "/Library/Filesystems",
-                  "/Library/Fonts",
-                  "/Library/Frameworks",
-                  "/Library/Graphics",
-                  "/Library/Image Capture",
-                  "/Library/Input Methods",
-                  "/Library/Internet Plug-Ins",
-                  "/Library/Java",
-                  "/Library/Keyboard Layouts",
-                  "/Library/Keychains",
-                  "/Library/LaunchAgents",
-                  "/Library/LaunchDaemons",
-                  "/Library/Logs",
-                  "/Library/Messages",
-                  "/Library/Modem Scripts",
-                  "/Library/OpenDirectory",
-                  "/Library/PDF Services",
-                  "/Library/Perl",
-                  "/Library/PreferencePanes",
-                  "/Library/Preferences",
-                  "/Library/Printers",
-                  "/Library/PrivilegedHelperTools",
-                  "/Library/Python",
-                  "/Library/QuickLook",
-                  "/Library/QuickTime",
-                  "/Library/Receipts",
-                  "/Library/Ruby",
-                  "/Library/Sandbox",
-                  "/Library/Screen Savers",
-                  "/Library/ScriptingAdditions",
-                  "/Library/Scripts",
-                  "/Library/Security",
-                  "/Library/Speech",
-                  "/Library/Spelling",
-                  "/Library/Spotlight",
-                  "/Library/StartupItems",
-                  "/Library/SystemProfiler",
-                  "/Library/Updates",
-                  "/Library/User Pictures",
-                  "/Library/Video",
-                  "/Library/WebServer",
-                  "/Library/Widgets",
-                  "/Library/iTunes",
-                  "/Network",
-                  "/System",
-                  "/System/Library",
-                  "/System/Library/Accessibility",
-                  "/System/Library/Accounts",
-                  "/System/Library/Address Book Plug-Ins",
-                  "/System/Library/Assistant",
-                  "/System/Library/Automator",
-                  "/System/Library/BridgeSupport",
-                  "/System/Library/Caches",
-                  "/System/Library/ColorPickers",
-                  "/System/Library/ColorSync",
-                  "/System/Library/Colors",
-                  "/System/Library/Components",
-                  "/System/Library/Compositions",
-                  "/System/Library/CoreServices",
-                  "/System/Library/DTDs",
-                  "/System/Library/DirectoryServices",
-                  "/System/Library/Displays",
-                  "/System/Library/Extensions",
-                  "/System/Library/Filesystems",
-                  "/System/Library/Filters",
-                  "/System/Library/Fonts",
-                  "/System/Library/Frameworks",
-                  "/System/Library/Graphics",
-                  "/System/Library/IdentityServices",
-                  "/System/Library/Image Capture",
-                  "/System/Library/Input Methods",
-                  "/System/Library/InternetAccounts",
-                  "/System/Library/Java",
-                  "/System/Library/KerberosPlugins",
-                  "/System/Library/Keyboard Layouts",
-                  "/System/Library/Keychains",
-                  "/System/Library/LaunchAgents",
-                  "/System/Library/LaunchDaemons",
-                  "/System/Library/LinguisticData",
-                  "/System/Library/LocationBundles",
-                  "/System/Library/LoginPlugins",
-                  "/System/Library/Messages",
-                  "/System/Library/Metadata",
-                  "/System/Library/MonitorPanels",
-                  "/System/Library/OpenDirectory",
-                  "/System/Library/OpenSSL",
-                  "/System/Library/Password Server Filters",
-                  "/System/Library/PerformanceMetrics",
-                  "/System/Library/Perl",
-                  "/System/Library/PreferencePanes",
-                  "/System/Library/Printers",
-                  "/System/Library/PrivateFrameworks",
-                  "/System/Library/QuickLook",
-                  "/System/Library/QuickTime",
-                  "/System/Library/QuickTimeJava",
-                  "/System/Library/Recents",
-                  "/System/Library/SDKSettingsPlist",
-                  "/System/Library/Sandbox",
-                  "/System/Library/Screen Savers",
-                  "/System/Library/ScreenReader",
-                  "/System/Library/ScriptingAdditions",
-                  "/System/Library/ScriptingDefinitions",
-                  "/System/Library/Security",
-                  "/System/Library/Services",
-                  "/System/Library/Sounds",
-                  "/System/Library/Speech",
-                  "/System/Library/Spelling",
-                  "/System/Library/Spotlight",
-                  "/System/Library/StartupItems",
-                  "/System/Library/SyncServices",
-                  "/System/Library/SystemConfiguration",
-                  "/System/Library/SystemProfiler",
-                  "/System/Library/Tcl",
-                  "/System/Library/TextEncodings",
-                  "/System/Library/User Template",
-                  "/System/Library/UserEventPlugins",
-                  "/System/Library/Video",
-                  "/System/Library/WidgetResources",
-                  "/User Information",
-                  "/Users",
-                  "/Volumes",
-                  "/bin",
-                  "/boot",
-                  "/cores",
-                  "/dev",
-                  "/etc",
-                  "/etc/X11",
-                  "/etc/opt",
-                  "/etc/sgml",
-                  "/etc/xml",
-                  "/home",
-                  "/libexec",
-                  "/lost+found",
-                  "/media",
-                  "/mnt",
-                  "/net",
-                  "/opt",
-                  "/private",
-                  "/private/etc",
-                  "/private/tftpboot",
-                  "/private/tmp",
-                  "/private/var",
-                  "/proc",
-                  "/root",
-                  "/sbin",
-                  "/srv",
-                  "/tmp",
-                  "/usr",
-                  "/usr/X11R6",
-                  "/usr/bin",
-                  "/usr/etc",
-                  "/usr/include",
-                  "/usr/lib",
-                  "/usr/libexec",
-                  "/usr/local",
-                  "/usr/local/Cellar",
-                  "/usr/local/Frameworks",
-                  "/usr/local/Library",
-                  "/usr/local/bin",
-                  "/usr/local/etc",
-                  "/usr/local/include",
-                  "/usr/local/lib",
-                  "/usr/local/libexec",
-                  "/usr/local/opt",
-                  "/usr/local/share",
-                  "/usr/local/share/man",
-                  "/usr/local/share/man/man1",
-                  "/usr/local/share/man/man2",
-                  "/usr/local/share/man/man3",
-                  "/usr/local/share/man/man4",
-                  "/usr/local/share/man/man5",
-                  "/usr/local/share/man/man6",
-                  "/usr/local/share/man/man7",
-                  "/usr/local/share/man/man8",
-                  "/usr/local/share/man/man9",
-                  "/usr/local/share/man/mann",
-                  "/usr/local/var",
-                  "/usr/local/var/lib",
-                  "/usr/local/var/lock",
-                  "/usr/local/var/run",
-                  "/usr/sbin",
-                  "/usr/share",
-                  "/usr/share/man",
-                  "/usr/share/man/man1",
-                  "/usr/share/man/man2",
-                  "/usr/share/man/man3",
-                  "/usr/share/man/man4",
-                  "/usr/share/man/man5",
-                  "/usr/share/man/man6",
-                  "/usr/share/man/man7",
-                  "/usr/share/man/man8",
-                  "/usr/share/man/man9",
-                  "/usr/share/man/mann",
-                  "/usr/src",
-                  "/var",
-                  "/var/cache",
-                  "/var/lib",
-                  "/var/lock",
-                  "/var/log",
-                  "/var/mail",
-                  "/var/run",
-                  "/var/spool",
-                  "/var/spool/mail",
-                  "/var/tmp",
-                ]
-                .map(&method(:Pathname))
-                .to_set
-                .freeze
+module OS
+  module Mac
+    SYSTEM_DIRS = [
+                    "/",
+                    "/Applications",
+                    "/Applications/Utilities",
+                    "/Incompatible Software",
+                    "/Library",
+                    "/Library/Application Support",
+                    "/Library/Audio",
+                    "/Library/Caches",
+                    "/Library/ColorPickers",
+                    "/Library/ColorSync",
+                    "/Library/Components",
+                    "/Library/Compositions",
+                    "/Library/Contextual Menu Items",
+                    "/Library/CoreMediaIO",
+                    "/Library/Desktop Pictures",
+                    "/Library/Developer",
+                    "/Library/Dictionaries",
+                    "/Library/DirectoryServices",
+                    "/Library/Documentation",
+                    "/Library/Extensions",
+                    "/Library/Filesystems",
+                    "/Library/Fonts",
+                    "/Library/Frameworks",
+                    "/Library/Graphics",
+                    "/Library/Image Capture",
+                    "/Library/Input Methods",
+                    "/Library/Internet Plug-Ins",
+                    "/Library/Java",
+                    "/Library/Keyboard Layouts",
+                    "/Library/Keychains",
+                    "/Library/LaunchAgents",
+                    "/Library/LaunchDaemons",
+                    "/Library/Logs",
+                    "/Library/Messages",
+                    "/Library/Modem Scripts",
+                    "/Library/OpenDirectory",
+                    "/Library/PDF Services",
+                    "/Library/Perl",
+                    "/Library/PreferencePanes",
+                    "/Library/Preferences",
+                    "/Library/Printers",
+                    "/Library/PrivilegedHelperTools",
+                    "/Library/Python",
+                    "/Library/QuickLook",
+                    "/Library/QuickTime",
+                    "/Library/Receipts",
+                    "/Library/Ruby",
+                    "/Library/Sandbox",
+                    "/Library/Screen Savers",
+                    "/Library/ScriptingAdditions",
+                    "/Library/Scripts",
+                    "/Library/Security",
+                    "/Library/Speech",
+                    "/Library/Spelling",
+                    "/Library/Spotlight",
+                    "/Library/StartupItems",
+                    "/Library/SystemProfiler",
+                    "/Library/Updates",
+                    "/Library/User Pictures",
+                    "/Library/Video",
+                    "/Library/WebServer",
+                    "/Library/Widgets",
+                    "/Library/iTunes",
+                    "/Network",
+                    "/System",
+                    "/System/Library",
+                    "/System/Library/Accessibility",
+                    "/System/Library/Accounts",
+                    "/System/Library/Address Book Plug-Ins",
+                    "/System/Library/Assistant",
+                    "/System/Library/Automator",
+                    "/System/Library/BridgeSupport",
+                    "/System/Library/Caches",
+                    "/System/Library/ColorPickers",
+                    "/System/Library/ColorSync",
+                    "/System/Library/Colors",
+                    "/System/Library/Components",
+                    "/System/Library/Compositions",
+                    "/System/Library/CoreServices",
+                    "/System/Library/DTDs",
+                    "/System/Library/DirectoryServices",
+                    "/System/Library/Displays",
+                    "/System/Library/Extensions",
+                    "/System/Library/Filesystems",
+                    "/System/Library/Filters",
+                    "/System/Library/Fonts",
+                    "/System/Library/Frameworks",
+                    "/System/Library/Graphics",
+                    "/System/Library/IdentityServices",
+                    "/System/Library/Image Capture",
+                    "/System/Library/Input Methods",
+                    "/System/Library/InternetAccounts",
+                    "/System/Library/Java",
+                    "/System/Library/KerberosPlugins",
+                    "/System/Library/Keyboard Layouts",
+                    "/System/Library/Keychains",
+                    "/System/Library/LaunchAgents",
+                    "/System/Library/LaunchDaemons",
+                    "/System/Library/LinguisticData",
+                    "/System/Library/LocationBundles",
+                    "/System/Library/LoginPlugins",
+                    "/System/Library/Messages",
+                    "/System/Library/Metadata",
+                    "/System/Library/MonitorPanels",
+                    "/System/Library/OpenDirectory",
+                    "/System/Library/OpenSSL",
+                    "/System/Library/Password Server Filters",
+                    "/System/Library/PerformanceMetrics",
+                    "/System/Library/Perl",
+                    "/System/Library/PreferencePanes",
+                    "/System/Library/Printers",
+                    "/System/Library/PrivateFrameworks",
+                    "/System/Library/QuickLook",
+                    "/System/Library/QuickTime",
+                    "/System/Library/QuickTimeJava",
+                    "/System/Library/Recents",
+                    "/System/Library/SDKSettingsPlist",
+                    "/System/Library/Sandbox",
+                    "/System/Library/Screen Savers",
+                    "/System/Library/ScreenReader",
+                    "/System/Library/ScriptingAdditions",
+                    "/System/Library/ScriptingDefinitions",
+                    "/System/Library/Security",
+                    "/System/Library/Services",
+                    "/System/Library/Sounds",
+                    "/System/Library/Speech",
+                    "/System/Library/Spelling",
+                    "/System/Library/Spotlight",
+                    "/System/Library/StartupItems",
+                    "/System/Library/SyncServices",
+                    "/System/Library/SystemConfiguration",
+                    "/System/Library/SystemProfiler",
+                    "/System/Library/Tcl",
+                    "/System/Library/TextEncodings",
+                    "/System/Library/User Template",
+                    "/System/Library/UserEventPlugins",
+                    "/System/Library/Video",
+                    "/System/Library/WidgetResources",
+                    "/User Information",
+                    "/Users",
+                    "/Volumes",
+                    "/bin",
+                    "/boot",
+                    "/cores",
+                    "/dev",
+                    "/etc",
+                    "/etc/X11",
+                    "/etc/opt",
+                    "/etc/sgml",
+                    "/etc/xml",
+                    "/home",
+                    "/libexec",
+                    "/lost+found",
+                    "/media",
+                    "/mnt",
+                    "/net",
+                    "/opt",
+                    "/private",
+                    "/private/etc",
+                    "/private/tftpboot",
+                    "/private/tmp",
+                    "/private/var",
+                    "/proc",
+                    "/root",
+                    "/sbin",
+                    "/srv",
+                    "/tmp",
+                    "/usr",
+                    "/usr/X11R6",
+                    "/usr/bin",
+                    "/usr/etc",
+                    "/usr/include",
+                    "/usr/lib",
+                    "/usr/libexec",
+                    "/usr/local",
+                    "/usr/local/Cellar",
+                    "/usr/local/Frameworks",
+                    "/usr/local/Library",
+                    "/usr/local/bin",
+                    "/usr/local/etc",
+                    "/usr/local/include",
+                    "/usr/local/lib",
+                    "/usr/local/libexec",
+                    "/usr/local/opt",
+                    "/usr/local/share",
+                    "/usr/local/share/man",
+                    "/usr/local/share/man/man1",
+                    "/usr/local/share/man/man2",
+                    "/usr/local/share/man/man3",
+                    "/usr/local/share/man/man4",
+                    "/usr/local/share/man/man5",
+                    "/usr/local/share/man/man6",
+                    "/usr/local/share/man/man7",
+                    "/usr/local/share/man/man8",
+                    "/usr/local/share/man/man9",
+                    "/usr/local/share/man/mann",
+                    "/usr/local/var",
+                    "/usr/local/var/lib",
+                    "/usr/local/var/lock",
+                    "/usr/local/var/run",
+                    "/usr/sbin",
+                    "/usr/share",
+                    "/usr/share/man",
+                    "/usr/share/man/man1",
+                    "/usr/share/man/man2",
+                    "/usr/share/man/man3",
+                    "/usr/share/man/man4",
+                    "/usr/share/man/man5",
+                    "/usr/share/man/man6",
+                    "/usr/share/man/man7",
+                    "/usr/share/man/man8",
+                    "/usr/share/man/man9",
+                    "/usr/share/man/mann",
+                    "/usr/src",
+                    "/var",
+                    "/var/cache",
+                    "/var/lib",
+                    "/var/lock",
+                    "/var/log",
+                    "/var/mail",
+                    "/var/run",
+                    "/var/spool",
+                    "/var/spool/mail",
+                    "/var/tmp",
+                  ]
+                  .map(&method(:Pathname))
+                  .to_set
+                  .freeze
 
-  # TODO: There should be a way to specify a containing
-  #       directory under which nothing can be deleted.
-  UNDELETABLE_DIRS = [
-                       "~/",
-                       "~/Applications",
-                       "~/Desktop",
-                       "~/Documents",
-                       "~/Downloads",
-                       "~/Mail",
-                       "~/Movies",
-                       "~/Music",
-                       "~/Music/iTunes",
-                       "~/Music/iTunes/iTunes Music",
-                       "~/Music/iTunes/Album Artwork",
-                       "~/News",
-                       "~/Pictures",
-                       "~/Pictures/Desktops",
-                       "~/Pictures/Photo Booth",
-                       "~/Pictures/iChat Icons",
-                       "~/Pictures/iPhoto Library",
-                       "~/Public",
-                       "~/Sites",
-                       "~/Library",
-                       "~/Library/.localized",
-                       "~/Library/Accessibility",
-                       "~/Library/Accounts",
-                       "~/Library/Address Book Plug-Ins",
-                       "~/Library/Application Scripts",
-                       "~/Library/Application Support",
-                       "~/Library/Application Support/Apple",
-                       "~/Library/Application Support/com.apple.AssistiveControl",
-                       "~/Library/Application Support/com.apple.QuickLook",
-                       "~/Library/Application Support/com.apple.TCC",
-                       "~/Library/Assistants",
-                       "~/Library/Audio",
-                       "~/Library/Automator",
-                       "~/Library/Autosave Information",
-                       "~/Library/Caches",
-                       "~/Library/Calendars",
-                       "~/Library/ColorPickers",
-                       "~/Library/ColorSync",
-                       "~/Library/Colors",
-                       "~/Library/Components",
-                       "~/Library/Compositions",
-                       "~/Library/Containers",
-                       "~/Library/Contextual Menu Items",
-                       "~/Library/Cookies",
-                       "~/Library/DTDs",
-                       "~/Library/Desktop Pictures",
-                       "~/Library/Developer",
-                       "~/Library/Dictionaries",
-                       "~/Library/DirectoryServices",
-                       "~/Library/Displays",
-                       "~/Library/Documentation",
-                       "~/Library/Extensions",
-                       "~/Library/Favorites",
-                       "~/Library/FileSync",
-                       "~/Library/Filesystems",
-                       "~/Library/Filters",
-                       "~/Library/FontCollections",
-                       "~/Library/Fonts",
-                       "~/Library/Frameworks",
-                       "~/Library/GameKit",
-                       "~/Library/Graphics",
-                       "~/Library/Group Containers",
-                       "~/Library/Icons",
-                       "~/Library/IdentityServices",
-                       "~/Library/Image Capture",
-                       "~/Library/Images",
-                       "~/Library/Input Methods",
-                       "~/Library/Internet Plug-Ins",
-                       "~/Library/InternetAccounts",
-                       "~/Library/iTunes",
-                       "~/Library/KeyBindings",
-                       "~/Library/Keyboard Layouts",
-                       "~/Library/Keychains",
-                       "~/Library/LaunchAgents",
-                       "~/Library/LaunchDaemons",
-                       "~/Library/LocationBundles",
-                       "~/Library/LoginPlugins",
-                       "~/Library/Logs",
-                       "~/Library/Mail",
-                       "~/Library/Mail Downloads",
-                       "~/Library/Messages",
-                       "~/Library/Metadata",
-                       "~/Library/Mobile Documents",
-                       "~/Library/MonitorPanels",
-                       "~/Library/OpenDirectory",
-                       "~/Library/PDF Services",
-                       "~/Library/PhonePlugins",
-                       "~/Library/Phones",
-                       "~/Library/PreferencePanes",
-                       "~/Library/Preferences",
-                       "~/Library/Printers",
-                       "~/Library/PrivateFrameworks",
-                       "~/Library/PubSub",
-                       "~/Library/QuickLook",
-                       "~/Library/QuickTime",
-                       "~/Library/Receipts",
-                       "~/Library/Recent Servers",
-                       "~/Library/Recents",
-                       "~/Library/Safari",
-                       "~/Library/Saved Application State",
-                       "~/Library/Screen Savers",
-                       "~/Library/ScreenReader",
-                       "~/Library/ScriptingAdditions",
-                       "~/Library/ScriptingDefinitions",
-                       "~/Library/Scripts",
-                       "~/Library/Security",
-                       "~/Library/Services",
-                       "~/Library/Sounds",
-                       "~/Library/Speech",
-                       "~/Library/Spelling",
-                       "~/Library/Spotlight",
-                       "~/Library/StartupItems",
-                       "~/Library/StickiesDatabase",
-                       "~/Library/Sync Services",
-                       "~/Library/SyncServices",
-                       "~/Library/SyncedPreferences",
-                       "~/Library/TextEncodings",
-                       "~/Library/User Pictures",
-                       "~/Library/Video",
-                       "~/Library/Voices",
-                       "~/Library/WebKit",
-                       "~/Library/WidgetResources",
-                       "~/Library/Widgets",
-                       "~/Library/Workflows",
-                     ]
-                     .map { |x| Pathname(x.sub(%r{^~(?=(/|$))}, Dir.home)).expand_path }
-                     .to_set
-                     .union(SYSTEM_DIRS)
-                     .freeze
+    # TODO: There should be a way to specify a containing
+    #       directory under which nothing can be deleted.
+    UNDELETABLE_DIRS = [
+                         "~/",
+                         "~/Applications",
+                         "~/Desktop",
+                         "~/Documents",
+                         "~/Downloads",
+                         "~/Mail",
+                         "~/Movies",
+                         "~/Music",
+                         "~/Music/iTunes",
+                         "~/Music/iTunes/iTunes Music",
+                         "~/Music/iTunes/Album Artwork",
+                         "~/News",
+                         "~/Pictures",
+                         "~/Pictures/Desktops",
+                         "~/Pictures/Photo Booth",
+                         "~/Pictures/iChat Icons",
+                         "~/Pictures/iPhoto Library",
+                         "~/Public",
+                         "~/Sites",
+                         "~/Library",
+                         "~/Library/.localized",
+                         "~/Library/Accessibility",
+                         "~/Library/Accounts",
+                         "~/Library/Address Book Plug-Ins",
+                         "~/Library/Application Scripts",
+                         "~/Library/Application Support",
+                         "~/Library/Application Support/Apple",
+                         "~/Library/Application Support/com.apple.AssistiveControl",
+                         "~/Library/Application Support/com.apple.QuickLook",
+                         "~/Library/Application Support/com.apple.TCC",
+                         "~/Library/Assistants",
+                         "~/Library/Audio",
+                         "~/Library/Automator",
+                         "~/Library/Autosave Information",
+                         "~/Library/Caches",
+                         "~/Library/Calendars",
+                         "~/Library/ColorPickers",
+                         "~/Library/ColorSync",
+                         "~/Library/Colors",
+                         "~/Library/Components",
+                         "~/Library/Compositions",
+                         "~/Library/Containers",
+                         "~/Library/Contextual Menu Items",
+                         "~/Library/Cookies",
+                         "~/Library/DTDs",
+                         "~/Library/Desktop Pictures",
+                         "~/Library/Developer",
+                         "~/Library/Dictionaries",
+                         "~/Library/DirectoryServices",
+                         "~/Library/Displays",
+                         "~/Library/Documentation",
+                         "~/Library/Extensions",
+                         "~/Library/Favorites",
+                         "~/Library/FileSync",
+                         "~/Library/Filesystems",
+                         "~/Library/Filters",
+                         "~/Library/FontCollections",
+                         "~/Library/Fonts",
+                         "~/Library/Frameworks",
+                         "~/Library/GameKit",
+                         "~/Library/Graphics",
+                         "~/Library/Group Containers",
+                         "~/Library/Icons",
+                         "~/Library/IdentityServices",
+                         "~/Library/Image Capture",
+                         "~/Library/Images",
+                         "~/Library/Input Methods",
+                         "~/Library/Internet Plug-Ins",
+                         "~/Library/InternetAccounts",
+                         "~/Library/iTunes",
+                         "~/Library/KeyBindings",
+                         "~/Library/Keyboard Layouts",
+                         "~/Library/Keychains",
+                         "~/Library/LaunchAgents",
+                         "~/Library/LaunchDaemons",
+                         "~/Library/LocationBundles",
+                         "~/Library/LoginPlugins",
+                         "~/Library/Logs",
+                         "~/Library/Mail",
+                         "~/Library/Mail Downloads",
+                         "~/Library/Messages",
+                         "~/Library/Metadata",
+                         "~/Library/Mobile Documents",
+                         "~/Library/MonitorPanels",
+                         "~/Library/OpenDirectory",
+                         "~/Library/PDF Services",
+                         "~/Library/PhonePlugins",
+                         "~/Library/Phones",
+                         "~/Library/PreferencePanes",
+                         "~/Library/Preferences",
+                         "~/Library/Printers",
+                         "~/Library/PrivateFrameworks",
+                         "~/Library/PubSub",
+                         "~/Library/QuickLook",
+                         "~/Library/QuickTime",
+                         "~/Library/Receipts",
+                         "~/Library/Recent Servers",
+                         "~/Library/Recents",
+                         "~/Library/Safari",
+                         "~/Library/Saved Application State",
+                         "~/Library/Screen Savers",
+                         "~/Library/ScreenReader",
+                         "~/Library/ScriptingAdditions",
+                         "~/Library/ScriptingDefinitions",
+                         "~/Library/Scripts",
+                         "~/Library/Security",
+                         "~/Library/Services",
+                         "~/Library/Sounds",
+                         "~/Library/Speech",
+                         "~/Library/Spelling",
+                         "~/Library/Spotlight",
+                         "~/Library/StartupItems",
+                         "~/Library/StickiesDatabase",
+                         "~/Library/Sync Services",
+                         "~/Library/SyncServices",
+                         "~/Library/SyncedPreferences",
+                         "~/Library/TextEncodings",
+                         "~/Library/User Pictures",
+                         "~/Library/Video",
+                         "~/Library/Voices",
+                         "~/Library/WebKit",
+                         "~/Library/WidgetResources",
+                         "~/Library/Widgets",
+                         "~/Library/Workflows",
+                       ]
+                       .map { |x| Pathname(x.sub(%r{^~(?=(/|$))}, Dir.home)).expand_path }
+                       .to_set
+                       .union(SYSTEM_DIRS)
+                       .freeze
 
-  def system_dir?(dir)
-    SYSTEM_DIRS.include?(Pathname.new(dir).expand_path)
-  end
+    def system_dir?(dir)
+      SYSTEM_DIRS.include?(Pathname.new(dir).expand_path)
+    end
 
-  def undeletable?(dir)
-    UNDELETABLE_DIRS.include?(Pathname.new(dir).expand_path)
+    def undeletable?(dir)
+      UNDELETABLE_DIRS.include?(Pathname.new(dir).expand_path)
+    end
   end
-
-  alias release version
 end
diff --git a/Library/Homebrew/cask/lib/hbc/options.rb b/Library/Homebrew/cask/lib/hbc/options.rb
index c0e3e2ed0..e9ba54ff6 100644
--- a/Library/Homebrew/cask/lib/hbc/options.rb
+++ b/Library/Homebrew/cask/lib/hbc/options.rb
@@ -1,37 +1,39 @@
-module Hbc::Options
-  def self.included(base)
-    base.extend(ClassMethods)
-  end
+module Hbc
+  module Options
+    def self.included(base)
+      base.extend(ClassMethods)
+    end
 
-  module ClassMethods
-    attr_writer :no_binaries
+    module ClassMethods
+      attr_writer :no_binaries
 
-    def no_binaries
-      @no_binaries ||= false
-    end
+      def no_binaries
+        @no_binaries ||= false
+      end
 
-    attr_writer :debug
+      attr_writer :debug
 
-    def debug
-      @debug ||= false
-    end
+      def debug
+        @debug ||= false
+      end
 
-    attr_writer :verbose
+      attr_writer :verbose
 
-    def verbose
-      @verbose ||= false
-    end
+      def verbose
+        @verbose ||= false
+      end
 
-    attr_writer :cleanup_outdated
+      attr_writer :cleanup_outdated
 
-    def cleanup_outdated
-      @cleanup_outdated ||= false
-    end
+      def cleanup_outdated
+        @cleanup_outdated ||= false
+      end
 
-    attr_writer :help
+      attr_writer :help
 
-    def help
-      @help ||= false
+      def help
+        @help ||= false
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/pkg.rb b/Library/Homebrew/cask/lib/hbc/pkg.rb
index 6f8d28c24..7f187c9de 100644
--- a/Library/Homebrew/cask/lib/hbc/pkg.rb
+++ b/Library/Homebrew/cask/lib/hbc/pkg.rb
@@ -1,113 +1,115 @@
-class Hbc::Pkg
-  def self.all_matching(regexp, command)
-    command.run("/usr/sbin/pkgutil", args: ["--pkgs=#{regexp}"]).stdout.split("\n").map { |package_id|
-      new(package_id.chomp, command)
-    }
-  end
+module Hbc
+  class Pkg
+    def self.all_matching(regexp, command)
+      command.run("/usr/sbin/pkgutil", args: ["--pkgs=#{regexp}"]).stdout.split("\n").map { |package_id|
+        new(package_id.chomp, command)
+      }
+    end
 
-  attr_reader :package_id
+    attr_reader :package_id
 
-  def initialize(package_id, command = Hbc::SystemCommand)
-    @package_id = package_id
-    @command = command
-  end
+    def initialize(package_id, command = SystemCommand)
+      @package_id = package_id
+      @command = command
+    end
 
-  def uninstall
-    odebug "Deleting pkg files"
-    pkgutil_bom_files.each_slice(500) do |file_slice|
-      @command.run("/bin/rm", args: file_slice.unshift("-f", "--"), sudo: true)
-    end
-    odebug "Deleting pkg symlinks and special files"
-    pkgutil_bom_specials.each_slice(500) do |file_slice|
-      @command.run("/bin/rm", args: file_slice.unshift("-f", "--"), sudo: true)
-    end
-    odebug "Deleting pkg directories"
-    _deepest_path_first(pkgutil_bom_dirs).each do |dir|
-      next unless dir.exist? && !MacOS.undeletable?(dir)
-      _with_full_permissions(dir) do
-        _clean_broken_symlinks(dir)
-        _clean_ds_store(dir)
-        _rmdir(dir)
+    def uninstall
+      odebug "Deleting pkg files"
+      pkgutil_bom_files.each_slice(500) do |file_slice|
+        @command.run("/bin/rm", args: file_slice.unshift("-f", "--"), sudo: true)
+      end
+      odebug "Deleting pkg symlinks and special files"
+      pkgutil_bom_specials.each_slice(500) do |file_slice|
+        @command.run("/bin/rm", args: file_slice.unshift("-f", "--"), sudo: true)
       end
+      odebug "Deleting pkg directories"
+      _deepest_path_first(pkgutil_bom_dirs).each do |dir|
+        next unless dir.exist? && !MacOS.undeletable?(dir)
+        _with_full_permissions(dir) do
+          _clean_broken_symlinks(dir)
+          _clean_ds_store(dir)
+          _rmdir(dir)
+        end
+      end
+      forget
     end
-    forget
-  end
 
-  def forget
-    odebug "Unregistering pkg receipt (aka forgetting)"
-    @command.run!("/usr/sbin/pkgutil", args: ["--forget", package_id], sudo: true)
-  end
+    def forget
+      odebug "Unregistering pkg receipt (aka forgetting)"
+      @command.run!("/usr/sbin/pkgutil", args: ["--forget", package_id], sudo: true)
+    end
 
-  def pkgutil_bom(*type)
-    @command.run!("/usr/sbin/pkgutil", args: [*type, "--files", package_id].compact)
-            .stdout
-            .split("\n")
-            .map { |path| root.join(path) }
-  end
+    def pkgutil_bom(*type)
+      @command.run!("/usr/sbin/pkgutil", args: [*type, "--files", package_id].compact)
+              .stdout
+              .split("\n")
+              .map { |path| root.join(path) }
+    end
 
-  def pkgutil_bom_files
-    @pkgutil_bom_files ||= pkgutil_bom("--only-files")
-  end
+    def pkgutil_bom_files
+      @pkgutil_bom_files ||= pkgutil_bom("--only-files")
+    end
 
-  def pkgutil_bom_dirs
-    @pkgutil_bom_dirs ||= pkgutil_bom("--only-dirs")
-  end
+    def pkgutil_bom_dirs
+      @pkgutil_bom_dirs ||= pkgutil_bom("--only-dirs")
+    end
 
-  def pkgutil_bom_all
-    @pkgutil_bom_all ||= pkgutil_bom
-  end
+    def pkgutil_bom_all
+      @pkgutil_bom_all ||= pkgutil_bom
+    end
 
-  def pkgutil_bom_specials
-    pkgutil_bom_all - pkgutil_bom_files - pkgutil_bom_dirs
-  end
+    def pkgutil_bom_specials
+      pkgutil_bom_all - pkgutil_bom_files - pkgutil_bom_dirs
+    end
 
-  def root
-    @root ||= Pathname(info.fetch("volume")).join(info.fetch("install-location"))
-  end
+    def root
+      @root ||= Pathname(info.fetch("volume")).join(info.fetch("install-location"))
+    end
 
-  def info
-    @command.run!("/usr/sbin/pkgutil", args: ["--pkg-info-plist", package_id])
-            .plist
-  end
+    def info
+      @command.run!("/usr/sbin/pkgutil", args: ["--pkg-info-plist", package_id])
+              .plist
+    end
 
-  def _rmdir(path)
-    @command.run!("/bin/rmdir", args: ["--", path], sudo: true) if path.children.empty?
-  end
+    def _rmdir(path)
+      @command.run!("/bin/rmdir", args: ["--", path], sudo: true) if path.children.empty?
+    end
 
-  def _with_full_permissions(path)
-    original_mode = (path.stat.mode % 0o1000).to_s(8)
-    # TODO: similarly read and restore macOS flags (cf man chflags)
-    @command.run!("/bin/chmod", args: ["--", "777", path], sudo: true)
-    yield
-  ensure
-    if path.exist? # block may have removed dir
-      @command.run!("/bin/chmod", args: ["--", original_mode, path], sudo: true)
+    def _with_full_permissions(path)
+      original_mode = (path.stat.mode % 0o1000).to_s(8)
+      # TODO: similarly read and restore macOS flags (cf man chflags)
+      @command.run!("/bin/chmod", args: ["--", "777", path], sudo: true)
+      yield
+    ensure
+      if path.exist? # block may have removed dir
+        @command.run!("/bin/chmod", args: ["--", original_mode, path], sudo: true)
+      end
     end
-  end
 
-  def _deepest_path_first(paths)
-    paths.sort do |path_a, path_b|
-      path_b.to_s.split("/").count <=> path_a.to_s.split("/").count
+    def _deepest_path_first(paths)
+      paths.sort do |path_a, path_b|
+        path_b.to_s.split("/").count <=> path_a.to_s.split("/").count
+      end
     end
-  end
 
-  # Some pkgs leave broken symlinks hanging around; we clean them out before
-  # attempting to rmdir to prevent extra cruft from lying around after
-  # uninstall
-  def _clean_broken_symlinks(dir)
-    dir.children.each do |child|
-      if _broken_symlink?(child)
-        @command.run!("/bin/rm", args: ["--", child], sudo: true)
+    # Some pkgs leave broken symlinks hanging around; we clean them out before
+    # attempting to rmdir to prevent extra cruft from lying around after
+    # uninstall
+    def _clean_broken_symlinks(dir)
+      dir.children.each do |child|
+        if _broken_symlink?(child)
+          @command.run!("/bin/rm", args: ["--", child], sudo: true)
+        end
       end
     end
-  end
 
-  def _clean_ds_store(dir)
-    ds_store = dir.join(".DS_Store")
-    @command.run!("/bin/rm", args: ["--", ds_store], sudo: true) if ds_store.exist?
-  end
+    def _clean_ds_store(dir)
+      ds_store = dir.join(".DS_Store")
+      @command.run!("/bin/rm", args: ["--", ds_store], sudo: true) if ds_store.exist?
+    end
 
-  def _broken_symlink?(path)
-    path.symlink? && !path.exist?
+    def _broken_symlink?(path)
+      path.symlink? && !path.exist?
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/qualified_token.rb b/Library/Homebrew/cask/lib/hbc/qualified_token.rb
index 635e1cb3d..ccfe08b45 100644
--- a/Library/Homebrew/cask/lib/hbc/qualified_token.rb
+++ b/Library/Homebrew/cask/lib/hbc/qualified_token.rb
@@ -1,37 +1,39 @@
-module Hbc::QualifiedToken
-  REPO_PREFIX = "homebrew-".freeze
+module Hbc
+  module QualifiedToken
+    REPO_PREFIX = "homebrew-".freeze
 
-  # per https://github.com/Homebrew/homebrew/blob/4c7bc9ec3bca729c898ee347b6135ba692ee0274/Library/Homebrew/cmd/tap.rb#L121
-  USER_REGEX = %r{[a-z_\-]+}
+    # per https://github.com/Homebrew/homebrew/blob/4c7bc9ec3bca729c898ee347b6135ba692ee0274/Library/Homebrew/cmd/tap.rb#L121
+    USER_REGEX = %r{[a-z_\-]+}
 
-  # per https://github.com/Homebrew/homebrew/blob/4c7bc9ec3bca729c898ee347b6135ba692ee0274/Library/Homebrew/cmd/tap.rb#L121
-  REPO_REGEX = %r{(?:#{REPO_PREFIX})?\w+}
+    # per https://github.com/Homebrew/homebrew/blob/4c7bc9ec3bca729c898ee347b6135ba692ee0274/Library/Homebrew/cmd/tap.rb#L121
+    REPO_REGEX = %r{(?:#{REPO_PREFIX})?\w+}
 
-  # per https://github.com/caskroom/homebrew-cask/blob/master/CONTRIBUTING.md#generating-a-token-for-the-cask
-  TOKEN_REGEX = %r{[a-z0-9\-]+}
+    # per https://github.com/caskroom/homebrew-cask/blob/master/CONTRIBUTING.md#generating-a-token-for-the-cask
+    TOKEN_REGEX = %r{[a-z0-9\-]+}
 
-  TAP_REGEX = %r{#{USER_REGEX}[/\-]#{REPO_REGEX}}
+    TAP_REGEX = %r{#{USER_REGEX}[/\-]#{REPO_REGEX}}
 
-  QUALIFIED_TOKEN_REGEX ||= %r{#{TAP_REGEX}/#{TOKEN_REGEX}}
+    QUALIFIED_TOKEN_REGEX ||= %r{#{TAP_REGEX}/#{TOKEN_REGEX}}
 
-  def self.parse(arg)
-    return nil unless arg.is_a?(String) && arg.downcase =~ %r{^#{QUALIFIED_TOKEN_REGEX}$}
-    path_elements = arg.downcase.split("/")
-    if path_elements.count == 2
-      # eg phinze-cask/google-chrome.
-      # Not certain this form is needed, but it was supported in the past.
-      token = path_elements[1]
-      dash_elements = path_elements[0].split("-")
-      repo = dash_elements.pop
-      dash_elements.pop if dash_elements.count > 1 && dash_elements[-1] + "-" == REPO_PREFIX
-      user = dash_elements.join("-")
-    else
-      # eg caskroom/cask/google-chrome
-      # per https://github.com/Homebrew/homebrew/wiki/brew-tap
-      user, repo, token = path_elements
+    def self.parse(arg)
+      return nil unless arg.is_a?(String) && arg.downcase =~ %r{^#{QUALIFIED_TOKEN_REGEX}$}
+      path_elements = arg.downcase.split("/")
+      if path_elements.count == 2
+        # eg phinze-cask/google-chrome.
+        # Not certain this form is needed, but it was supported in the past.
+        token = path_elements[1]
+        dash_elements = path_elements[0].split("-")
+        repo = dash_elements.pop
+        dash_elements.pop if dash_elements.count > 1 && dash_elements[-1] + "-" == REPO_PREFIX
+        user = dash_elements.join("-")
+      else
+        # eg caskroom/cask/google-chrome
+        # per https://github.com/Homebrew/homebrew/wiki/brew-tap
+        user, repo, token = path_elements
+      end
+      repo.sub!(%r{^#{REPO_PREFIX}}, "")
+      odebug "[user, repo, token] might be [#{user}, #{repo}, #{token}]"
+      [user, repo, token]
     end
-    repo.sub!(%r{^#{REPO_PREFIX}}, "")
-    odebug "[user, repo, token] might be [#{user}, #{repo}, #{token}]"
-    [user, repo, token]
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/scopes.rb b/Library/Homebrew/cask/lib/hbc/scopes.rb
index 431c3ff47..8520028c9 100644
--- a/Library/Homebrew/cask/lib/hbc/scopes.rb
+++ b/Library/Homebrew/cask/lib/hbc/scopes.rb
@@ -1,45 +1,47 @@
-module Hbc::Scopes
-  def self.included(base)
-    base.extend(ClassMethods)
-  end
-
-  module ClassMethods
-    def all
-      @all_casks ||= {}
-      all_tokens.map { |t| @all_casks[t] ||= load(t) }
+module Hbc
+  module Scopes
+    def self.included(base)
+      base.extend(ClassMethods)
     end
 
-    def all_tapped_cask_dirs
-      Tap.map(&:cask_dir).compact
-    end
+    module ClassMethods
+      def all
+        @all_casks ||= {}
+        all_tokens.map { |t| @all_casks[t] ||= load(t) }
+      end
 
-    def all_tokens
-      Tap.map { |t|
-        t.cask_files.map { |p|
-          "#{t.name}/#{File.basename(p, ".rb")}"
-        }
-      }.flatten
-    end
+      def all_tapped_cask_dirs
+        Tap.map(&:cask_dir).compact
+      end
 
-    def installed
-      # Hbc.load has some DWIM which is slow.  Optimize here
-      # by spoon-feeding Hbc.load fully-qualified paths.
-      # TODO: speed up Hbc::Source::Tapped (main perf drag is calling Hbc.all_tokens repeatedly)
-      # TODO: ability to specify expected source when calling Hbc.load (minor perf benefit)
-      Pathname.glob(caskroom.join("*"))
-              .map { |caskroom_path|
-                token = caskroom_path.basename.to_s
+      def all_tokens
+        Tap.map { |t|
+          t.cask_files.map { |p|
+            "#{t.name}/#{File.basename(p, ".rb")}"
+          }
+        }.flatten
+      end
 
-                path_to_cask = all_tapped_cask_dirs.find { |tap_dir|
-                  tap_dir.join("#{token}.rb").exist?
-                }
+      def installed
+        # Hbc.load has some DWIM which is slow.  Optimize here
+        # by spoon-feeding Hbc.load fully-qualified paths.
+        # TODO: speed up Hbc::Source::Tapped (main perf drag is calling Hbc.all_tokens repeatedly)
+        # TODO: ability to specify expected source when calling Hbc.load (minor perf benefit)
+        Pathname.glob(caskroom.join("*"))
+                .map { |caskroom_path|
+                  token = caskroom_path.basename.to_s
+
+                  path_to_cask = all_tapped_cask_dirs.find { |tap_dir|
+                    tap_dir.join("#{token}.rb").exist?
+                  }
 
-                if path_to_cask
-                  Hbc.load(path_to_cask.join("#{token}.rb"))
-                else
-                  Hbc.load(token)
-                end
-              }
+                  if path_to_cask
+                    Hbc.load(path_to_cask.join("#{token}.rb"))
+                  else
+                    Hbc.load(token)
+                  end
+                }
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/source.rb b/Library/Homebrew/cask/lib/hbc/source.rb
index af298108a..b4d105894 100644
--- a/Library/Homebrew/cask/lib/hbc/source.rb
+++ b/Library/Homebrew/cask/lib/hbc/source.rb
@@ -1,5 +1,3 @@
-module Hbc::Source; end
-
 require "hbc/source/gone"
 require "hbc/source/path_slash_required"
 require "hbc/source/path_slash_optional"
@@ -8,30 +6,32 @@ require "hbc/source/untapped_qualified"
 require "hbc/source/tapped"
 require "hbc/source/uri"
 
-module Hbc::Source
-  def self.sources
-    [
-      Hbc::Source::URI,
-      Hbc::Source::PathSlashRequired,
-      Hbc::Source::TappedQualified,
-      Hbc::Source::UntappedQualified,
-      Hbc::Source::Tapped,
-      Hbc::Source::PathSlashOptional,
-      Hbc::Source::Gone,
-    ]
-  end
+module Hbc
+  module Source
+    def self.sources
+      [
+        URI,
+        PathSlashRequired,
+        TappedQualified,
+        UntappedQualified,
+        Tapped,
+        PathSlashOptional,
+        Gone,
+      ]
+    end
 
-  def self.for_query(query)
-    odebug "Translating '#{query}' into a valid Cask source"
-    raise Hbc::CaskUnavailableError, query if query.to_s =~ %r{^\s*$}
-    source = sources.find { |s|
-      odebug "Testing source class #{s}"
-      s.me?(query)
-    }
-    raise Hbc::CaskUnavailableError, query unless source
-    odebug "Success! Using source class #{source}"
-    resolved_cask_source = source.new(query)
-    odebug "Resolved Cask URI or file source to '#{resolved_cask_source}'"
-    resolved_cask_source
+    def self.for_query(query)
+      odebug "Translating '#{query}' into a valid Cask source"
+      raise CaskUnavailableError, query if query.to_s =~ %r{^\s*$}
+      source = sources.find { |s|
+        odebug "Testing source class #{s}"
+        s.me?(query)
+      }
+      raise CaskUnavailableError, query unless source
+      odebug "Success! Using source class #{source}"
+      resolved_cask_source = source.new(query)
+      odebug "Resolved Cask URI or file source to '#{resolved_cask_source}'"
+      resolved_cask_source
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/source/gone.rb b/Library/Homebrew/cask/lib/hbc/source/gone.rb
index 2b9f2b5f2..1c744d0db 100644
--- a/Library/Homebrew/cask/lib/hbc/source/gone.rb
+++ b/Library/Homebrew/cask/lib/hbc/source/gone.rb
@@ -1,19 +1,23 @@
-class Hbc::Source::Gone
-  def self.me?(query)
-    Hbc::WithoutSource.new(query).installed?
-  end
+module Hbc
+  module Source
+    class Gone
+      def self.me?(query)
+        WithoutSource.new(query).installed?
+      end
 
-  attr_reader :query
+      attr_reader :query
 
-  def initialize(query)
-    @query = query
-  end
+      def initialize(query)
+        @query = query
+      end
 
-  def load
-    Hbc::WithoutSource.new(query)
-  end
+      def load
+        WithoutSource.new(query)
+      end
 
-  def to_s
-    ""
+      def to_s
+        ""
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/source/path_base.rb b/Library/Homebrew/cask/lib/hbc/source/path_base.rb
index bd85ab425..5725380ec 100644
--- a/Library/Homebrew/cask/lib/hbc/source/path_base.rb
+++ b/Library/Homebrew/cask/lib/hbc/source/path_base.rb
@@ -1,69 +1,73 @@
 require "rubygems"
 
-class Hbc::Source::PathBase
-  # derived classes must define method self.me?
+module Hbc
+  module Source
+    class PathBase
+      # derived classes must define method self.me?
 
-  def self.path_for_query(query)
-    query_string = query.to_s
-    Pathname.new(query_string.end_with?(".rb") ? query_string : query_string + ".rb")
-  end
+      def self.path_for_query(query)
+        query_string = query.to_s
+        Pathname.new(query_string.end_with?(".rb") ? query_string : query_string + ".rb")
+      end
 
-  attr_reader :path
+      attr_reader :path
 
-  def initialize(path)
-    @path = Pathname(path).expand_path
-  end
+      def initialize(path)
+        @path = Pathname(path).expand_path
+      end
 
-  def load
-    raise Hbc::CaskError, "File '#{path}' does not exist"      unless path.exist?
-    raise Hbc::CaskError, "File '#{path}' is not readable"     unless path.readable?
-    raise Hbc::CaskError, "File '#{path}' is not a plain file" unless path.file?
-    load_cask
-  end
+      def load
+        raise CaskError, "File '#{path}' does not exist"      unless path.exist?
+        raise CaskError, "File '#{path}' is not readable"     unless path.readable?
+        raise CaskError, "File '#{path}' is not a plain file" unless path.file?
+        load_cask
+      end
 
-  def to_s
-    # stringify to fully-resolved location
-    path.to_s
-  end
+      def to_s
+        # stringify to fully-resolved location
+        path.to_s
+      end
 
-  private
+      private
 
-  def load_cask
-    instance_eval(cask_contents, __FILE__, __LINE__)
-  rescue Hbc::CaskError, StandardError, ScriptError => e
-    # bug: e.message.concat doesn't work with Hbc::CaskError exceptions
-    raise e, e.message.concat(" while loading '#{path}'")
-  end
+      def load_cask
+        instance_eval(cask_contents, __FILE__, __LINE__)
+      rescue CaskError, StandardError, ScriptError => e
+        # bug: e.message.concat doesn't work with CaskError exceptions
+        raise e, e.message.concat(" while loading '#{path}'")
+      end
 
-  def cask_contents
-    File.open(path, "rb") do |handle|
-      contents = handle.read
-      if defined?(Encoding)
-        contents.force_encoding("UTF-8")
-      else
-        contents
+      def cask_contents
+        File.open(path, "rb") do |handle|
+          contents = handle.read
+          if defined?(Encoding)
+            contents.force_encoding("UTF-8")
+          else
+            contents
+          end
+        end
       end
-    end
-  end
 
-  def cask(header_token, &block)
-    build_cask(Hbc::Cask, header_token, &block)
-  end
+      def cask(header_token, &block)
+        build_cask(Cask, header_token, &block)
+      end
 
-  def test_cask(header_token, &block)
-    build_cask(Hbc::TestCask, header_token, &block)
-  end
+      def test_cask(header_token, &block)
+        build_cask(TestCask, header_token, &block)
+      end
 
-  def build_cask(cask_class, header_token, &block)
-    if header_token.is_a?(Hash)
-      # Cask file is using old `cask :v1 => 'token'` syntax
-      header_token = header_token.values.first
-    end
-    raise Hbc::CaskTokenDoesNotMatchError.new(cask_token, header_token) unless cask_token == header_token
-    cask_class.new(cask_token, sourcefile_path: path, &block)
-  end
+      def build_cask(cask_class, header_token, &block)
+        if header_token.is_a?(Hash)
+          # Cask file is using old `cask :v1 => 'token'` syntax
+          header_token = header_token.values.first
+        end
+        raise CaskTokenDoesNotMatchError.new(cask_token, header_token) unless cask_token == header_token
+        cask_class.new(cask_token, sourcefile_path: path, &block)
+      end
 
-  def cask_token
-    path.basename.to_s.sub(%r{\.rb}, "")
+      def cask_token
+        path.basename.to_s.sub(%r{\.rb}, "")
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/source/path_slash_optional.rb b/Library/Homebrew/cask/lib/hbc/source/path_slash_optional.rb
index fb34c481a..d96a41130 100644
--- a/Library/Homebrew/cask/lib/hbc/source/path_slash_optional.rb
+++ b/Library/Homebrew/cask/lib/hbc/source/path_slash_optional.rb
@@ -1,8 +1,12 @@
 require "hbc/source/path_base"
 
-class Hbc::Source::PathSlashOptional < Hbc::Source::PathBase
-  def self.me?(query)
-    path = path_for_query(query)
-    path.exist?
+module Hbc
+  module Source
+    class PathSlashOptional < PathBase
+      def self.me?(query)
+        path = path_for_query(query)
+        path.exist?
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/source/path_slash_required.rb b/Library/Homebrew/cask/lib/hbc/source/path_slash_required.rb
index 0c533a8a5..2753b1710 100644
--- a/Library/Homebrew/cask/lib/hbc/source/path_slash_required.rb
+++ b/Library/Homebrew/cask/lib/hbc/source/path_slash_required.rb
@@ -1,8 +1,12 @@
 require "hbc/source/path_base"
 
-class Hbc::Source::PathSlashRequired < Hbc::Source::PathBase
-  def self.me?(query)
-    path = path_for_query(query)
-    path.to_s.include?("/") && path.exist?
+module Hbc
+  module Source
+    class PathSlashRequired < PathBase
+      def self.me?(query)
+        path = path_for_query(query)
+        path.to_s.include?("/") && path.exist?
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/source/tapped.rb b/Library/Homebrew/cask/lib/hbc/source/tapped.rb
index da9366840..6716e3a35 100644
--- a/Library/Homebrew/cask/lib/hbc/source/tapped.rb
+++ b/Library/Homebrew/cask/lib/hbc/source/tapped.rb
@@ -1,35 +1,39 @@
-class Hbc::Source::Tapped
-  def self.me?(query)
-    path_for_query(query).exist?
-  end
+module Hbc
+  module Source
+    class Tapped
+      def self.me?(query)
+        path_for_query(query).exist?
+      end
 
-  def self.path_for_query(query)
-    # Repeating Hbc.all_tokens is very slow for operations such as
-    # brew cask list, but memoizing the value might cause breakage
-    # elsewhere, given that installation and tap status is permitted
-    # to change during the course of an invocation.
-    token_with_tap = Hbc.all_tokens.find { |t| t.split("/").last == query.sub(%r{\.rb$}i, "") }
-    if token_with_tap
-      user, repo, token = token_with_tap.split("/")
-      Tap.fetch(user, repo).cask_dir.join("#{token}.rb")
-    else
-      Hbc.default_tap.cask_dir.join(query.sub(%r{(\.rb)?$}i, ".rb"))
-    end
-  end
+      def self.path_for_query(query)
+        # Repeating Hbc.all_tokens is very slow for operations such as
+        # brew cask list, but memoizing the value might cause breakage
+        # elsewhere, given that installation and tap status is permitted
+        # to change during the course of an invocation.
+        token_with_tap = Hbc.all_tokens.find { |t| t.split("/").last == query.sub(%r{\.rb$}i, "") }
+        if token_with_tap
+          user, repo, token = token_with_tap.split("/")
+          Tap.fetch(user, repo).cask_dir.join("#{token}.rb")
+        else
+          Hbc.default_tap.cask_dir.join(query.sub(%r{(\.rb)?$}i, ".rb"))
+        end
+      end
 
-  attr_reader :token
+      attr_reader :token
 
-  def initialize(token)
-    @token = token
-  end
+      def initialize(token)
+        @token = token
+      end
 
-  def load
-    path = self.class.path_for_query(token)
-    Hbc::Source::PathSlashOptional.new(path).load
-  end
+      def load
+        path = self.class.path_for_query(token)
+        PathSlashOptional.new(path).load
+      end
 
-  def to_s
-    # stringify to fully-resolved location
-    self.class.path_for_query(token).expand_path.to_s
+      def to_s
+        # stringify to fully-resolved location
+        self.class.path_for_query(token).expand_path.to_s
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/source/tapped_qualified.rb b/Library/Homebrew/cask/lib/hbc/source/tapped_qualified.rb
index 1da013db2..52191f279 100644
--- a/Library/Homebrew/cask/lib/hbc/source/tapped_qualified.rb
+++ b/Library/Homebrew/cask/lib/hbc/source/tapped_qualified.rb
@@ -1,22 +1,26 @@
 require "hbc/source/tapped"
 
-class Hbc::Source::TappedQualified < Hbc::Source::Tapped
-  def self.me?(query)
-    return if (tap = tap_for_query(query)).nil?
+module Hbc
+  module Source
+    class TappedQualified < Tapped
+      def self.me?(query)
+        return if (tap = tap_for_query(query)).nil?
 
-    tap.installed? && path_for_query(query).exist?
-  end
+        tap.installed? && path_for_query(query).exist?
+      end
 
-  def self.tap_for_query(query)
-    qualified_token = Hbc::QualifiedToken.parse(query)
-    return if qualified_token.nil?
+      def self.tap_for_query(query)
+        qualified_token = QualifiedToken.parse(query)
+        return if qualified_token.nil?
 
-    user, repo, token = qualified_token
-    Tap.fetch(user, repo)
-  end
+        user, repo = qualified_token[0..1]
+        Tap.fetch(user, repo)
+      end
 
-  def self.path_for_query(query)
-    user, repo, token = Hbc::QualifiedToken.parse(query)
-    Tap.fetch(user, repo).cask_dir.join(token.sub(%r{(\.rb)?$}i, ".rb"))
+      def self.path_for_query(query)
+        user, repo, token = QualifiedToken.parse(query)
+        Tap.fetch(user, repo).cask_dir.join(token.sub(%r{(\.rb)?$}i, ".rb"))
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/source/untapped_qualified.rb b/Library/Homebrew/cask/lib/hbc/source/untapped_qualified.rb
index 7188d34ce..6041605d8 100644
--- a/Library/Homebrew/cask/lib/hbc/source/untapped_qualified.rb
+++ b/Library/Homebrew/cask/lib/hbc/source/untapped_qualified.rb
@@ -1,10 +1,14 @@
 require "hbc/source/tapped_qualified"
 
-class Hbc::Source::UntappedQualified < Hbc::Source::TappedQualified
-  def self.me?(query)
-    return if (tap = tap_for_query(query)).nil?
+module Hbc
+  module Source
+    class UntappedQualified < TappedQualified
+      def self.me?(query)
+        return if (tap = tap_for_query(query)).nil?
 
-    tap.install
-    tap.installed? && path_for_query(query).exist?
+        tap.install
+        tap.installed? && path_for_query(query).exist?
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/source/uri.rb b/Library/Homebrew/cask/lib/hbc/source/uri.rb
index 99bc50688..09fab4bd0 100644
--- a/Library/Homebrew/cask/lib/hbc/source/uri.rb
+++ b/Library/Homebrew/cask/lib/hbc/source/uri.rb
@@ -1,28 +1,32 @@
-class Hbc::Source::URI
-  def self.me?(query)
-    !(query.to_s =~ URI.regexp).nil?
-  end
+module Hbc
+  module Source
+    class URI
+      def self.me?(query)
+        !(query.to_s =~ ::URI.regexp).nil?
+      end
 
-  attr_reader :uri
+      attr_reader :uri
 
-  def initialize(uri)
-    @uri = uri
-  end
+      def initialize(uri)
+        @uri = uri
+      end
 
-  def load
-    Hbc.cache.mkpath
-    path = Hbc.cache.join(File.basename(uri))
-    ohai "Downloading #{uri}"
-    odebug "Download target -> #{path}"
-    begin
-      curl(uri, "-o", path.to_s)
-    rescue ErrorDuringExecution
-      raise Hbc::CaskUnavailableError, uri
-    end
-    Hbc::Source::PathSlashOptional.new(path).load
-  end
+      def load
+        Hbc.cache.mkpath
+        path = Hbc.cache.join(File.basename(uri))
+        ohai "Downloading #{uri}"
+        odebug "Download target -> #{path}"
+        begin
+          curl(uri, "-o", path.to_s)
+        rescue ErrorDuringExecution
+          raise CaskUnavailableError, uri
+        end
+        PathSlashOptional.new(path).load
+      end
 
-  def to_s
-    uri.to_s
+      def to_s
+        uri.to_s
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/staged.rb b/Library/Homebrew/cask/lib/hbc/staged.rb
index 7e2c93541..dcc05ef5d 100644
--- a/Library/Homebrew/cask/lib/hbc/staged.rb
+++ b/Library/Homebrew/cask/lib/hbc/staged.rb
@@ -1,48 +1,50 @@
-module Hbc::Staged
-  def info_plist_file(index = 0)
-    index =  0 if index == :first
-    index =  1 if index == :second
-    index = -1 if index == :last
-    Hbc.appdir.join(@cask.artifacts[:app].to_a.at(index).first, "Contents", "Info.plist")
-  end
-
-  def plist_exec(cmd)
-    @command.run!("/usr/libexec/PlistBuddy", args: ["-c", cmd, info_plist_file])
-  end
-
-  def plist_set(key, value)
-    plist_exec("Set #{key} #{value}")
-  rescue StandardError => e
-    raise Hbc::CaskError, "#{@cask.token}: 'plist_set' failed with: #{e}"
-  end
-
-  def bundle_identifier
-    plist_exec("Print CFBundleIdentifier").stdout.chomp
-  rescue StandardError => e
-    raise Hbc::CaskError, "#{@cask.token}: 'bundle_identifier' failed with: #{e}"
-  end
-
-  def set_permissions(paths, permissions_str)
-    full_paths = remove_nonexistent(paths)
-    return if full_paths.empty?
-    @command.run!("/bin/chmod", args: ["-R", "--", permissions_str] + full_paths,
-                                sudo: true)
-  end
-
-  def set_ownership(paths, user: current_user, group: "staff")
-    full_paths = remove_nonexistent(paths)
-    return if full_paths.empty?
-    @command.run!("/usr/sbin/chown", args: ["-R", "--", "#{user}:#{group}"] + full_paths,
-                                     sudo: true)
-  end
-
-  def current_user
-    Hbc::Utils.current_user
-  end
-
-  private
-
-  def remove_nonexistent(paths)
-    Array(paths).map { |p| Pathname(p).expand_path }.select(&:exist?)
+module Hbc
+  module Staged
+    def info_plist_file(index = 0)
+      index =  0 if index == :first
+      index =  1 if index == :second
+      index = -1 if index == :last
+      Hbc.appdir.join(@cask.artifacts[:app].to_a.at(index).first, "Contents", "Info.plist")
+    end
+
+    def plist_exec(cmd)
+      @command.run!("/usr/libexec/PlistBuddy", args: ["-c", cmd, info_plist_file])
+    end
+
+    def plist_set(key, value)
+      plist_exec("Set #{key} #{value}")
+    rescue StandardError => e
+      raise CaskError, "#{@cask.token}: 'plist_set' failed with: #{e}"
+    end
+
+    def bundle_identifier
+      plist_exec("Print CFBundleIdentifier").stdout.chomp
+    rescue StandardError => e
+      raise CaskError, "#{@cask.token}: 'bundle_identifier' failed with: #{e}"
+    end
+
+    def set_permissions(paths, permissions_str)
+      full_paths = remove_nonexistent(paths)
+      return if full_paths.empty?
+      @command.run!("/bin/chmod", args: ["-R", "--", permissions_str] + full_paths,
+                                  sudo: true)
+    end
+
+    def set_ownership(paths, user: current_user, group: "staff")
+      full_paths = remove_nonexistent(paths)
+      return if full_paths.empty?
+      @command.run!("/usr/sbin/chown", args: ["-R", "--", "#{user}:#{group}"] + full_paths,
+                                       sudo: true)
+    end
+
+    def current_user
+      Utils.current_user
+    end
+
+    private
+
+    def remove_nonexistent(paths)
+      Array(paths).map { |p| Pathname(p).expand_path }.select(&:exist?)
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/system_command.rb b/Library/Homebrew/cask/lib/hbc/system_command.rb
index bb8d91504..160aadff9 100644
--- a/Library/Homebrew/cask/lib/hbc/system_command.rb
+++ b/Library/Homebrew/cask/lib/hbc/system_command.rb
@@ -1,173 +1,179 @@
 require "open3"
 require "shellwords"
 
-class Hbc::SystemCommand
-  attr_reader :command
+module Hbc
+  class SystemCommand
+    attr_reader :command
 
-  def self.run(executable, options = {})
-    new(executable, options).run!
-  end
+    def self.run(executable, options = {})
+      new(executable, options).run!
+    end
 
-  def self.run!(command, options = {})
-    run(command, options.merge(must_succeed: true))
-  end
+    def self.run!(command, options = {})
+      run(command, options.merge(must_succeed: true))
+    end
 
-  def run!
-    @processed_output = { stdout: "", stderr: "" }
-    odebug "Executing: #{expanded_command.utf8_inspect}"
-
-    each_output_line do |type, line|
-      case type
-      when :stdout
-        processed_output[:stdout] << line
-        ohai line.chomp if options[:print_stdout]
-      when :stderr
-        processed_output[:stderr] << line
-        ohai line.chomp if options[:print_stderr]
+    def run!
+      @processed_output = { stdout: "", stderr: "" }
+      odebug "Executing: #{expanded_command.utf8_inspect}"
+
+      each_output_line do |type, line|
+        case type
+        when :stdout
+          processed_output[:stdout] << line
+          ohai line.chomp if options[:print_stdout]
+        when :stderr
+          processed_output[:stderr] << line
+          ohai line.chomp if options[:print_stderr]
+        end
       end
-    end
 
-    assert_success if options[:must_succeed]
-    result
-  end
+      assert_success if options[:must_succeed]
+      result
+    end
 
-  def initialize(executable, options)
-    @executable = executable
-    @options = options
-    process_options!
-  end
+    def initialize(executable, options)
+      @executable = executable
+      @options = options
+      process_options!
+    end
 
-  private
-
-  attr_reader :executable, :options, :processed_output, :processed_status
-
-  def process_options!
-    options.assert_valid_keys :input, :print_stdout, :print_stderr, :args, :must_succeed, :sudo, :bsexec
-    sudo_prefix = %w[/usr/bin/sudo -E --]
-    bsexec_prefix = ["/bin/launchctl", "bsexec", options[:bsexec] == :startup ? "/" : options[:bsexec]]
-    @command = [executable]
-    options[:print_stderr] = true    unless options.key?(:print_stderr)
-    @command.unshift(*bsexec_prefix) if  options[:bsexec]
-    @command.unshift(*sudo_prefix)   if  options[:sudo]
-    @command.concat(options[:args])  if  options.key?(:args) && !options[:args].empty?
-    @command[0] = Shellwords.shellescape(@command[0]) if @command.size == 1
-    nil
-  end
+    private
+
+    attr_reader :executable, :options, :processed_output, :processed_status
+
+    def process_options!
+      options.assert_valid_keys :input, :print_stdout, :print_stderr, :args, :must_succeed, :sudo, :bsexec
+      sudo_prefix = %w[/usr/bin/sudo -E --]
+      bsexec_prefix = ["/bin/launchctl", "bsexec", options[:bsexec] == :startup ? "/" : options[:bsexec]]
+      @command = [executable]
+      options[:print_stderr] = true    unless options.key?(:print_stderr)
+      @command.unshift(*bsexec_prefix) if  options[:bsexec]
+      @command.unshift(*sudo_prefix)   if  options[:sudo]
+      @command.concat(options[:args])  if  options.key?(:args) && !options[:args].empty?
+      @command[0] = Shellwords.shellescape(@command[0]) if @command.size == 1
+      nil
+    end
 
-  def assert_success
-    return if processed_status && processed_status.success?
-    raise Hbc::CaskCommandFailedError.new(command.utf8_inspect, processed_output[:stdout], processed_output[:stderr], processed_status)
-  end
+    def assert_success
+      return if processed_status && processed_status.success?
+      raise CaskCommandFailedError.new(command.utf8_inspect, processed_output[:stdout], processed_output[:stderr], processed_status)
+    end
 
-  def expanded_command
-    @expanded_command ||= command.map { |arg|
-      if arg.respond_to?(:to_path)
-        File.absolute_path(arg)
-      else
-        String(arg)
-      end
-    }
-  end
+    def expanded_command
+      @expanded_command ||= command.map { |arg|
+        if arg.respond_to?(:to_path)
+          File.absolute_path(arg)
+        else
+          String(arg)
+        end
+      }
+    end
 
-  def each_output_line(&b)
-    raw_stdin, raw_stdout, raw_stderr, raw_wait_thr =
-      Open3.popen3(*expanded_command)
+    def each_output_line(&b)
+      raw_stdin, raw_stdout, raw_stderr, raw_wait_thr =
+        Open3.popen3(*expanded_command)
 
-    write_input_to(raw_stdin) if options[:input]
-    raw_stdin.close_write
-    each_line_from [raw_stdout, raw_stderr], &b
+      write_input_to(raw_stdin) if options[:input]
+      raw_stdin.close_write
+      each_line_from [raw_stdout, raw_stderr], &b
 
-    @processed_status = raw_wait_thr.value
-  end
+      @processed_status = raw_wait_thr.value
+    end
 
-  def write_input_to(raw_stdin)
-    Array(options[:input]).each { |line| raw_stdin.puts line }
-  end
+    def write_input_to(raw_stdin)
+      Array(options[:input]).each { |line| raw_stdin.puts line }
+    end
 
-  def each_line_from(sources)
-    loop do
-      readable_sources = IO.select(sources)[0]
-      readable_sources.delete_if(&:eof?).first(1).each do |source|
-        type = (source == sources[0] ? :stdout : :stderr)
-        begin
-          yield(type, source.readline_nonblock || "")
-        rescue IO::WaitReadable, EOFError
-          next
+    def each_line_from(sources)
+      loop do
+        readable_sources = IO.select(sources)[0]
+        readable_sources.delete_if(&:eof?).first(1).each do |source|
+          type = (source == sources[0] ? :stdout : :stderr)
+          begin
+            yield(type, source.readline_nonblock || "")
+          rescue IO::WaitReadable, EOFError
+            next
+          end
         end
+        break if readable_sources.empty?
       end
-      break if readable_sources.empty?
+      sources.each(&:close_read)
     end
-    sources.each(&:close_read)
-  end
 
-  def result
-    Hbc::SystemCommand::Result.new(command,
-                                   processed_output[:stdout],
-                                   processed_output[:stderr],
-                                   processed_status.exitstatus)
+    def result
+      Result.new(command,
+                 processed_output[:stdout],
+                 processed_output[:stderr],
+                 processed_status.exitstatus)
+    end
   end
 end
 
-class Hbc::SystemCommand::Result
-  attr_accessor :command, :stdout, :stderr, :exit_status
+module Hbc
+  class SystemCommand
+    class Result
+      attr_accessor :command, :stdout, :stderr, :exit_status
 
-  def initialize(command, stdout, stderr, exit_status)
-    @command     = command
-    @stdout      = stdout
-    @stderr      = stderr
-    @exit_status = exit_status
-  end
+      def initialize(command, stdout, stderr, exit_status)
+        @command     = command
+        @stdout      = stdout
+        @stderr      = stderr
+        @exit_status = exit_status
+      end
 
-  def plist
-    @plist ||= self.class._parse_plist(@command, @stdout.dup)
-  end
+      def plist
+        @plist ||= self.class._parse_plist(@command, @stdout.dup)
+      end
 
-  def success?
-    @exit_status == 0
-  end
+      def success?
+        @exit_status.zero?
+      end
 
-  def merged_output
-    @merged_output ||= @stdout + @stderr
-  end
+      def merged_output
+        @merged_output ||= @stdout + @stderr
+      end
 
-  def to_s
-    @stdout
-  end
+      def to_s
+        @stdout
+      end
 
-  def self._warn_plist_garbage(command, garbage)
-    return true unless garbage =~ %r{\S}
-    external = File.basename(command.first)
-    lines = garbage.strip.split("\n")
-    opoo "Non-XML stdout from #{external}:"
-    $stderr.puts lines.map { |l| "    #{l}" }
-  end
+      def self._warn_plist_garbage(command, garbage)
+        return true unless garbage =~ %r{\S}
+        external = File.basename(command.first)
+        lines = garbage.strip.split("\n")
+        opoo "Non-XML stdout from #{external}:"
+        $stderr.puts lines.map { |l| "    #{l}" }
+      end
 
-  def self._parse_plist(command, output)
-    raise Hbc::CaskError, "Empty plist input" unless output =~ %r{\S}
-    output.sub!(%r{\A(.*?)(<\?\s*xml)}m, '\2')
-    _warn_plist_garbage(command, Regexp.last_match[1]) if Hbc.debug
-    output.sub!(%r{(<\s*/\s*plist\s*>)(.*?)\Z}m, '\1')
-    _warn_plist_garbage(command, Regexp.last_match[2])
-    xml = Plist.parse_xml(output)
-    unless xml.respond_to?(:keys) && !xml.keys.empty?
-      raise Hbc::CaskError, <<-EOS
-Empty result parsing plist output from command.
-  command was:
-  #{command.utf8_inspect}
-  output we attempted to parse:
-  #{output}
-      EOS
+      def self._parse_plist(command, output)
+        raise CaskError, "Empty plist input" unless output =~ %r{\S}
+        output.sub!(%r{\A(.*?)(<\?\s*xml)}m, '\2')
+        _warn_plist_garbage(command, Regexp.last_match[1]) if Hbc.debug
+        output.sub!(%r{(<\s*/\s*plist\s*>)(.*?)\Z}m, '\1')
+        _warn_plist_garbage(command, Regexp.last_match[2])
+        xml = Plist.parse_xml(output)
+        unless xml.respond_to?(:keys) && !xml.keys.empty?
+          raise CaskError, <<-EOS
+    Empty result parsing plist output from command.
+      command was:
+      #{command.utf8_inspect}
+      output we attempted to parse:
+      #{output}
+          EOS
+        end
+        xml
+      rescue Plist::ParseError => e
+        raise CaskError, <<-EOS
+    Error parsing plist output from command.
+      command was:
+      #{command.utf8_inspect}
+      error was:
+      #{e}
+      output we attempted to parse:
+      #{output}
+        EOS
+      end
     end
-    xml
-  rescue Plist::ParseError => e
-    raise Hbc::CaskError, <<-EOS
-Error parsing plist output from command.
-  command was:
-  #{command.utf8_inspect}
-  error was:
-  #{e}
-  output we attempted to parse:
-  #{output}
-    EOS
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/topological_hash.rb b/Library/Homebrew/cask/lib/hbc/topological_hash.rb
index bbad1bb4d..2e484a28d 100644
--- a/Library/Homebrew/cask/lib/hbc/topological_hash.rb
+++ b/Library/Homebrew/cask/lib/hbc/topological_hash.rb
@@ -1,12 +1,14 @@
 require "tsort"
 
 # a basic topologically sortable hashmap
-class Hbc::TopologicalHash < Hash
-  include TSort
+module Hbc
+  class TopologicalHash < Hash
+    include TSort
 
-  alias tsort_each_node each_key
+    alias tsort_each_node each_key
 
-  def tsort_each_child(node, &block)
-    fetch(node).each(&block)
+    def tsort_each_child(node, &block)
+      fetch(node).each(&block)
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/underscore_supporting_uri.rb b/Library/Homebrew/cask/lib/hbc/underscore_supporting_uri.rb
index 34bfea387..8f8f66f43 100644
--- a/Library/Homebrew/cask/lib/hbc/underscore_supporting_uri.rb
+++ b/Library/Homebrew/cask/lib/hbc/underscore_supporting_uri.rb
@@ -1,26 +1,28 @@
 require "uri"
 
-module Hbc::UnderscoreSupportingURI
-  def self.parse(maybe_uri)
-    return nil if maybe_uri.nil?
-    URI.parse(maybe_uri)
-  rescue URI::InvalidURIError => e
-    scheme, host, path = simple_parse(maybe_uri)
-    raise e unless path && host.include?("_")
-    URI.parse(without_host_underscores(scheme, host, path)).tap do |uri|
-      uri.instance_variable_set("@host", host)
+module Hbc
+  module UnderscoreSupportingURI
+    def self.parse(maybe_uri)
+      return nil if maybe_uri.nil?
+      URI.parse(maybe_uri)
+    rescue URI::InvalidURIError => e
+      scheme, host, path = simple_parse(maybe_uri)
+      raise e unless path && host.include?("_")
+      URI.parse(without_host_underscores(scheme, host, path)).tap do |uri|
+        uri.instance_variable_set("@host", host)
+      end
     end
-  end
 
-  def self.simple_parse(maybe_uri)
-    scheme, host_and_path = maybe_uri.split("://")
-    host, path = host_and_path.split("/", 2)
-    [scheme, host, path]
-  rescue StandardError
-    nil
-  end
+    def self.simple_parse(maybe_uri)
+      scheme, host_and_path = maybe_uri.split("://")
+      host, path = host_and_path.split("/", 2)
+      [scheme, host, path]
+    rescue StandardError
+      nil
+    end
 
-  def self.without_host_underscores(scheme, host, path)
-    ["#{scheme}:/", host.tr("_", "-"), path].join("/")
+    def self.without_host_underscores(scheme, host, path)
+      ["#{scheme}:/", host.tr("_", "-"), path].join("/")
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/url.rb b/Library/Homebrew/cask/lib/hbc/url.rb
index 5f763ca8a..c09aaa061 100644
--- a/Library/Homebrew/cask/lib/hbc/url.rb
+++ b/Library/Homebrew/cask/lib/hbc/url.rb
@@ -1,37 +1,39 @@
 require "forwardable"
 
-class Hbc::URL
-  FAKE_USER_AGENT = "Mozilla/5.0 (Macintosh; Intel Mac OS X 10) http://caskroom.io".freeze
+module Hbc
+  class URL
+    FAKE_USER_AGENT = "Mozilla/5.0 (Macintosh; Intel Mac OS X 10) http://caskroom.io".freeze
 
-  attr_reader :using, :revision, :trust_cert, :uri, :cookies, :referer, :data
+    attr_reader :using, :revision, :trust_cert, :uri, :cookies, :referer, :data
 
-  extend Forwardable
-  def_delegators :uri, :path, :scheme, :to_s
+    extend Forwardable
+    def_delegators :uri, :path, :scheme, :to_s
 
-  def self.from(*args, &block)
-    if block_given?
-      Hbc::DSL::StanzaProxy.once(self) { new(*block.call) }
-    else
-      new(*args)
+    def self.from(*args, &block)
+      if block_given?
+        Hbc::DSL::StanzaProxy.once(self) { new(*block.call) }
+      else
+        new(*args)
+      end
     end
-  end
 
-  def initialize(uri, options = {})
-    @uri        = Hbc::UnderscoreSupportingURI.parse(uri)
-    @user_agent = options[:user_agent]
-    @cookies    = options[:cookies]
-    @referer    = options[:referer]
-    @using      = options[:using]
-    @revision   = options[:revision]
-    @trust_cert = options[:trust_cert]
-    @data       = options[:data]
-  end
+    def initialize(uri, options = {})
+      @uri        = Hbc::UnderscoreSupportingURI.parse(uri)
+      @user_agent = options[:user_agent]
+      @cookies    = options[:cookies]
+      @referer    = options[:referer]
+      @using      = options[:using]
+      @revision   = options[:revision]
+      @trust_cert = options[:trust_cert]
+      @data       = options[:data]
+    end
 
-  def user_agent
-    if @user_agent == :fake
-      FAKE_USER_AGENT
-    else
-      @user_agent
+    def user_agent
+      if @user_agent == :fake
+        FAKE_USER_AGENT
+      else
+        @user_agent
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/url_checker.rb b/Library/Homebrew/cask/lib/hbc/url_checker.rb
index 8737903df..4dc1f136a 100644
--- a/Library/Homebrew/cask/lib/hbc/url_checker.rb
+++ b/Library/Homebrew/cask/lib/hbc/url_checker.rb
@@ -1,75 +1,77 @@
 require "hbc/checkable"
 
-class Hbc::UrlChecker
-  attr_accessor :cask, :response_status, :headers
+module Hbc
+  class UrlChecker
+    attr_accessor :cask, :response_status, :headers
 
-  include Hbc::Checkable
+    include Checkable
 
-  def initialize(cask, fetcher = Hbc::Fetcher)
-    @cask = cask
-    @fetcher = fetcher
-    @headers = {}
-  end
+    def initialize(cask, fetcher = Fetcher)
+      @cask = cask
+      @fetcher = fetcher
+      @headers = {}
+    end
 
-  def summary_header
-    "url check result for #{cask}"
-  end
+    def summary_header
+      "url check result for #{cask}"
+    end
 
-  def run
-    _get_data_from_request
-    return if errors?
-    _check_response_status
-  end
+    def run
+      _get_data_from_request
+      return if errors?
+      _check_response_status
+    end
 
-  HTTP_RESPONSES = [
-                     "HTTP/1.0 200 OK",
-                     "HTTP/1.1 200 OK",
-                     "HTTP/1.1 302 Found",
-                   ].freeze
+    HTTP_RESPONSES = [
+                       "HTTP/1.0 200 OK",
+                       "HTTP/1.1 200 OK",
+                       "HTTP/1.1 302 Found",
+                     ].freeze
 
-  OK_RESPONSES = {
-                   "http"  => HTTP_RESPONSES,
-                   "https" => HTTP_RESPONSES,
-                   "ftp"   => ["OK"],
-                 }.freeze
+    OK_RESPONSES = {
+                     "http"  => HTTP_RESPONSES,
+                     "https" => HTTP_RESPONSES,
+                     "ftp"   => ["OK"],
+                   }.freeze
 
-  def _check_response_status
-    ok = OK_RESPONSES[cask.url.scheme]
-    return if ok.include?(@response_status)
-    add_error "unexpected http response, expecting #{ok.map(&:utf8_inspect).join(' or ')}, got #{@response_status.utf8_inspect}"
-  end
+    def _check_response_status
+      ok = OK_RESPONSES[cask.url.scheme]
+      return if ok.include?(@response_status)
+      add_error "unexpected http response, expecting #{ok.map(&:utf8_inspect).join(" or ")}, got #{@response_status.utf8_inspect}"
+    end
 
-  def _get_data_from_request
-    response = @fetcher.head(cask.url)
+    def _get_data_from_request
+      response = @fetcher.head(cask.url)
 
-    if response.empty?
-      add_error "timeout while requesting #{cask.url}"
-      return
-    end
+      if response.empty?
+        add_error "timeout while requesting #{cask.url}"
+        return
+      end
 
-    response_lines = response.split("\n").map(&:chomp)
+      response_lines = response.split("\n").map(&:chomp)
 
-    case cask.url.scheme
-    when "http", "https" then
-      @response_status = response_lines.grep(%r{^HTTP}).last
-      if @response_status.respond_to?(:strip)
-        @response_status.strip!
-        unless response_lines.index(@response_status).nil?
-          http_headers = response_lines[(response_lines.index(@response_status) + 1)..-1]
-          http_headers.each do |line|
-            header_name, header_value = line.split(": ")
-            @headers[header_name] = header_value
+      case cask.url.scheme
+      when "http", "https" then
+        @response_status = response_lines.grep(%r{^HTTP}).last
+        if @response_status.respond_to?(:strip)
+          @response_status.strip!
+          unless response_lines.index(@response_status).nil?
+            http_headers = response_lines[(response_lines.index(@response_status) + 1)..-1]
+            http_headers.each do |line|
+              header_name, header_value = line.split(": ")
+              @headers[header_name] = header_value
+            end
           end
         end
+      when "ftp" then
+        @response_status = "OK"
+        response_lines.each do |line|
+          header_name, header_value = line.split(": ")
+          @headers[header_name] = header_value
+        end
+      else
+        add_error "unknown scheme for #{cask.url}"
       end
-    when "ftp" then
-      @response_status = "OK"
-      response_lines.each do |line|
-        header_name, header_value = line.split(": ")
-        @headers[header_name] = header_value
-      end
-    else
-      add_error "unknown scheme for #{cask.url}"
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/utils.rb b/Library/Homebrew/cask/lib/hbc/utils.rb
index 599127523..9159544a6 100644
--- a/Library/Homebrew/cask/lib/hbc/utils.rb
+++ b/Library/Homebrew/cask/lib/hbc/utils.rb
@@ -1,5 +1,3 @@
-module Hbc::Utils; end
-
 require "yaml"
 require "open3"
 require "stringio"
@@ -32,165 +30,168 @@ end
 # global methods
 
 def odebug(title, *sput)
-  if Hbc.respond_to?(:debug) && Hbc.debug
-    width = Tty.width * 4 - 6
-    if $stdout.tty? && title.to_s.length > width
-      title = title.to_s[0, width - 3] + "..."
-    end
-    puts "#{Tty.magenta}==>#{Tty.reset} #{Tty.white}#{title}#{Tty.reset}"
-    puts sput unless sput.empty?
+  return unless Hbc.respond_to?(:debug)
+  return unless Hbc.debug
+
+  width = Tty.width * 4 - 6
+  if $stdout.tty? && title.to_s.length > width
+    title = title.to_s[0, width - 3] + "..."
   end
+  puts "#{Tty.magenta}==>#{Tty.reset} #{Tty.white}#{title}#{Tty.reset}"
+  puts sput unless sput.empty?
 end
 
-module Hbc::Utils
-  def self.which(cmd, path = ENV["PATH"])
-    unless File.basename(cmd) == cmd.to_s
-      # cmd contains a directory element
+module Hbc
+  module Utils
+    def self.which(cmd, path = ENV["PATH"])
+      unless File.basename(cmd) == cmd.to_s
+        # cmd contains a directory element
+        cmd_pn = Pathname(cmd)
+        return nil unless cmd_pn.absolute?
+        return resolve_executable(cmd_pn)
+      end
+      path.split(File::PATH_SEPARATOR).each do |elt|
+        fq_cmd = Pathname(elt).expand_path.join(cmd)
+        resolved = resolve_executable fq_cmd
+        return resolved if resolved
+      end
+      nil
+    end
+
+    def self.resolve_executable(cmd)
       cmd_pn = Pathname(cmd)
-      return nil unless cmd_pn.absolute?
-      return resolve_executable(cmd_pn)
+      return nil unless cmd_pn.exist?
+      return nil unless cmd_pn.executable?
+      begin
+        cmd_pn = Pathname(cmd_pn.realpath)
+      rescue RuntimeError
+        return nil
+      end
+      return nil unless cmd_pn.file?
+      cmd_pn
     end
-    path.split(File::PATH_SEPARATOR).each do |elt|
-      fq_cmd = Pathname(elt).expand_path.join(cmd)
-      resolved = resolve_executable fq_cmd
-      return resolved if resolved
+
+    def self.gain_permissions_remove(path, command: SystemCommand)
+      if path.respond_to?(:rmtree) && path.exist?
+        gain_permissions(path, ["-R"], command, &:rmtree)
+      elsif File.symlink?(path)
+        gain_permissions(path, ["-h"], command, &FileUtils.method(:rm_f))
+      end
     end
-    nil
-  end
 
-  def self.resolve_executable(cmd)
-    cmd_pn = Pathname(cmd)
-    return nil unless cmd_pn.exist?
-    return nil unless cmd_pn.executable?
-    begin
-      cmd_pn = Pathname(cmd_pn.realpath)
-    rescue RuntimeError
-      return nil
+    def self.gain_permissions(path, command_args, command)
+      tried_permissions = false
+      tried_ownership = false
+      begin
+        yield path
+      rescue StandardError
+        # in case of permissions problems
+        unless tried_permissions
+          # TODO: Better handling for the case where path is a symlink.
+          #       The -h and -R flags cannot be combined, and behavior is
+          #       dependent on whether the file argument has a trailing
+          #       slash.  This should do the right thing, but is fragile.
+          command.run("/usr/bin/chflags",
+                      must_succeed: false,
+                      args:         command_args + ["--", "000", path])
+          command.run("/bin/chmod",
+                      must_succeed: false,
+                      args:         command_args + ["--", "u+rwx", path])
+          command.run("/bin/chmod",
+                      must_succeed: false,
+                      args:         command_args + ["-N", path])
+          tried_permissions = true
+          retry # rmtree
+        end
+        unless tried_ownership
+          # in case of ownership problems
+          # TODO: Further examine files to see if ownership is the problem
+          #       before using sudo+chown
+          ohai "Using sudo to gain ownership of path '#{path}'"
+          command.run("/usr/sbin/chown",
+                      args: command_args + ["--", current_user, path],
+                      sudo: true)
+          tried_ownership = true
+          # retry chflags/chmod after chown
+          tried_permissions = false
+          retry # rmtree
+        end
+      end
     end
-    return nil unless cmd_pn.file?
-    cmd_pn
-  end
 
-  def self.gain_permissions_remove(path, command: Hbc::SystemCommand)
-    if path.respond_to?(:rmtree) && path.exist?
-      gain_permissions(path, ["-R"], command, &:rmtree)
-    elsif File.symlink?(path)
-      gain_permissions(path, ["-h"], command, &FileUtils.method(:rm_f))
+    def self.current_user
+      Etc.getpwuid(Process.euid).name
     end
-  end
 
-  def self.gain_permissions(path, command_args, command)
-    tried_permissions = false
-    tried_ownership = false
-    begin
-      yield path
-    rescue StandardError
-      # in case of permissions problems
-      unless tried_permissions
-        # TODO: Better handling for the case where path is a symlink.
-        #       The -h and -R flags cannot be combined, and behavior is
-        #       dependent on whether the file argument has a trailing
-        #       slash.  This should do the right thing, but is fragile.
-        command.run("/usr/bin/chflags",
-                    must_succeed: false,
-                    args:         command_args + ["--", "000", path])
-        command.run("/bin/chmod",
-                    must_succeed: false,
-                    args:         command_args + ["--", "u+rwx", path])
-        command.run("/bin/chmod",
-                    must_succeed: false,
-                    args:         command_args + ["-N", path])
-        tried_permissions = true
-        retry # rmtree
+    # paths that "look" descendant (textually) will still
+    # return false unless both the given paths exist
+    def self.file_is_descendant(file, dir)
+      file = Pathname.new(file)
+      dir  = Pathname.new(dir)
+      return false unless file.exist? && dir.exist?
+      unless dir.directory?
+        onoe "Argument must be a directory: '#{dir}'"
+        return false
       end
-      unless tried_ownership
-        # in case of ownership problems
-        # TODO: Further examine files to see if ownership is the problem
-        #       before using sudo+chown
-        ohai "Using sudo to gain ownership of path '#{path}'"
-        command.run("/usr/sbin/chown",
-                    args: command_args + ["--", current_user, path],
-                    sudo: true)
-        tried_ownership = true
-        # retry chflags/chmod after chown
-        tried_permissions = false
-        retry # rmtree
+      unless file.absolute? && dir.absolute?
+        onoe "Both arguments must be absolute: '#{file}', '#{dir}'"
+        return false
       end
+      while file.parent != file
+        return true if File.identical?(file, dir)
+        file = file.parent
+      end
+      false
     end
-  end
 
-  def self.current_user
-    Etc.getpwuid(Process.euid).name
-  end
-
-  # paths that "look" descendant (textually) will still
-  # return false unless both the given paths exist
-  def self.file_is_descendant(file, dir)
-    file = Pathname.new(file)
-    dir  = Pathname.new(dir)
-    return false unless file.exist? && dir.exist?
-    unless dir.directory?
-      onoe "Argument must be a directory: '#{dir}'"
-      return false
-    end
-    unless file.absolute? && dir.absolute?
-      onoe "Both arguments must be absolute: '#{file}', '#{dir}'"
-      return false
-    end
-    while file.parent != file
-      return true if File.identical?(file, dir)
-      file = file.parent
+    def self.path_occupied?(path)
+      File.exist?(path) || File.symlink?(path)
     end
-    false
-  end
-
-  def self.path_occupied?(path)
-    File.exist?(path) || File.symlink?(path)
-  end
 
-  def self.error_message_with_suggestions
-    <<-EOS.undent
-      Most likely, this means you have an outdated version of Homebrew-Cask. Please run:
+    def self.error_message_with_suggestions
+      <<-EOS.undent
+        Most likely, this means you have an outdated version of Homebrew-Cask. Please run:
 
-          #{Tty.green}#{UPDATE_CMD}
+            #{Tty.green}#{UPDATE_CMD}
 
-      #{Tty.reset}If this doesn’t fix the problem, please report this bug:
+        #{Tty.reset}If this doesn’t fix the problem, please report this bug:
 
-          #{Tty.em}#{ISSUES_URL}#{Tty.reset}
+            #{Tty.em}#{ISSUES_URL}#{Tty.reset}
 
-    EOS
-  end
+      EOS
+    end
 
-  def self.method_missing_message(method, token, section = nil)
-    poo = []
-    poo << "Unexpected method '#{method}' called"
-    poo << "during #{section}" if section
-    poo << "on Cask #{token}."
+    def self.method_missing_message(method, token, section = nil)
+      poo = []
+      poo << "Unexpected method '#{method}' called"
+      poo << "during #{section}" if section
+      poo << "on Cask #{token}."
 
-    opoo(poo.join(" ") + "\n" + error_message_with_suggestions)
-  end
+      opoo(poo.join(" ") + "\n" + error_message_with_suggestions)
+    end
 
-  def self.nowstamp_metadata_path(container_path)
-    @timenow ||= Time.now.gmtime
-    if container_path.respond_to?(:join)
-      precision = 3
-      timestamp = @timenow.strftime("%Y%m%d%H%M%S")
-      fraction = format("%.#{precision}f", @timenow.to_f - @timenow.to_i)[1..-1]
-      timestamp.concat(fraction)
-      container_path.join(timestamp)
+    def self.nowstamp_metadata_path(container_path)
+      @timenow ||= Time.now.gmtime
+      if container_path.respond_to?(:join)
+        precision = 3
+        timestamp = @timenow.strftime("%Y%m%d%H%M%S")
+        fraction = format("%.#{precision}f", @timenow.to_f - @timenow.to_i)[1..-1]
+        timestamp.concat(fraction)
+        container_path.join(timestamp)
+      end
     end
-  end
 
-  def self.size_in_bytes(files)
-    Array(files).reduce(0) { |a, e| a + (File.size?(e) || 0) }
-  end
+    def self.size_in_bytes(files)
+      Array(files).reduce(0) { |a, e| a + (File.size?(e) || 0) }
+    end
 
-  def self.capture_stderr
-    previous_stderr = $stderr
-    $stderr = StringIO.new
-    yield
-    $stderr.string
-  ensure
-    $stderr = previous_stderr
+    def self.capture_stderr
+      previous_stderr = $stderr
+      $stderr = StringIO.new
+      yield
+      $stderr.string
+    ensure
+      $stderr = previous_stderr
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/utils/file.rb b/Library/Homebrew/cask/lib/hbc/utils/file.rb
index 967c6834f..6b80f33ce 100644
--- a/Library/Homebrew/cask/lib/hbc/utils/file.rb
+++ b/Library/Homebrew/cask/lib/hbc/utils/file.rb
@@ -1,12 +1,14 @@
-module Hbc::Utils
-  module_function
+module Hbc
+  module Utils
+    module_function
 
-  def file_locked?(file)
-    unlocked = File.open(file).flock(File::LOCK_EX | File::LOCK_NB)
-    # revert lock if file was unlocked before check
-    File.open(file).flock(File::LOCK_UN) if unlocked
-    !unlocked
-  rescue
-    true
+    def file_locked?(file)
+      unlocked = File.open(file).flock(File::LOCK_EX | File::LOCK_NB)
+      # revert lock if file was unlocked before check
+      File.open(file).flock(File::LOCK_UN) if unlocked
+      !unlocked
+    rescue
+      true
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/verify.rb b/Library/Homebrew/cask/lib/hbc/verify.rb
index d3c2713e7..dbf3d0e88 100644
--- a/Library/Homebrew/cask/lib/hbc/verify.rb
+++ b/Library/Homebrew/cask/lib/hbc/verify.rb
@@ -1,33 +1,33 @@
-module Hbc::Verify; end
-
 require "hbc/verify/checksum"
 require "hbc/verify/gpg"
 
-module Hbc::Verify
-  module_function
+module Hbc
+  module Verify
+    module_function
 
-  def verifications
-    [
-      Hbc::Verify::Checksum
-      # TODO: Hbc::Verify::Gpg
-    ]
-  end
+    def verifications
+      [
+        Hbc::Verify::Checksum
+        # TODO: Hbc::Verify::Gpg
+      ]
+    end
 
-  def all(cask, downloaded_path)
-    odebug "Verifying download"
-    verifications = for_cask(cask)
-    odebug "#{verifications.size} verifications defined", verifications
-    verifications.each do |verification|
-      odebug "Running verification of class #{verification}"
-      verification.new(cask, downloaded_path).verify
+    def all(cask, downloaded_path)
+      odebug "Verifying download"
+      verifications = for_cask(cask)
+      odebug "#{verifications.size} verifications defined", verifications
+      verifications.each do |verification|
+        odebug "Running verification of class #{verification}"
+        verification.new(cask, downloaded_path).verify
+      end
     end
-  end
 
-  def for_cask(cask)
-    odebug "Determining which verifications to run for Cask #{cask}"
-    verifications.select do |verification|
-      odebug "Checking for verification class #{verification}"
-      verification.me?(cask)
+    def for_cask(cask)
+      odebug "Determining which verifications to run for Cask #{cask}"
+      verifications.select do |verification|
+        odebug "Checking for verification class #{verification}"
+        verification.me?(cask)
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/verify/checksum.rb b/Library/Homebrew/cask/lib/hbc/verify/checksum.rb
index 3af6f1667..d079a4446 100644
--- a/Library/Homebrew/cask/lib/hbc/verify/checksum.rb
+++ b/Library/Homebrew/cask/lib/hbc/verify/checksum.rb
@@ -1,43 +1,47 @@
 require "digest"
 
-class Hbc::Verify::Checksum
-  def self.me?(cask)
-    return true unless cask.sha256 == :no_check
-    ohai "No checksum defined for Cask #{cask}, skipping verification"
-    false
-  end
-
-  attr_reader :cask, :downloaded_path
-
-  def initialize(cask, downloaded_path)
-    @cask = cask
-    @downloaded_path = downloaded_path
-  end
-
-  def verify
-    return unless self.class.me?(cask)
-    ohai "Verifying checksum for Cask #{cask}"
-    verify_checksum
-  end
-
-  private
-
-  def expected
-    @expected ||= cask.sha256
-  end
-
-  def computed
-    @computed ||= Digest::SHA2.file(downloaded_path).hexdigest
-  end
-
-  def verify_checksum
-    raise Hbc::CaskSha256MissingError, "sha256 required: sha256 '#{computed}'" if expected.nil? || expected.empty?
-
-    if expected == computed
-      odebug "SHA256 checksums match"
-    else
-      ohai 'Note: running "brew update" may fix sha256 checksum errors'
-      raise Hbc::CaskSha256MismatchError.new(downloaded_path, expected, computed)
+module Hbc
+  module Verify
+    class Checksum
+      def self.me?(cask)
+        return true unless cask.sha256 == :no_check
+        ohai "No checksum defined for Cask #{cask}, skipping verification"
+        false
+      end
+
+      attr_reader :cask, :downloaded_path
+
+      def initialize(cask, downloaded_path)
+        @cask = cask
+        @downloaded_path = downloaded_path
+      end
+
+      def verify
+        return unless self.class.me?(cask)
+        ohai "Verifying checksum for Cask #{cask}"
+        verify_checksum
+      end
+
+      private
+
+      def expected
+        @expected ||= cask.sha256
+      end
+
+      def computed
+        @computed ||= Digest::SHA2.file(downloaded_path).hexdigest
+      end
+
+      def verify_checksum
+        raise CaskSha256MissingError, "sha256 required: sha256 '#{computed}'" if expected.nil? || expected.empty?
+
+        if expected == computed
+          odebug "SHA256 checksums match"
+        else
+          ohai 'Note: running "brew update" may fix sha256 checksum errors'
+          raise CaskSha256MismatchError.new(downloaded_path, expected, computed)
+        end
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/verify/gpg.rb b/Library/Homebrew/cask/lib/hbc/verify/gpg.rb
index 6190f67d1..6eb5fc23b 100644
--- a/Library/Homebrew/cask/lib/hbc/verify/gpg.rb
+++ b/Library/Homebrew/cask/lib/hbc/verify/gpg.rb
@@ -1,60 +1,64 @@
-class Hbc::Verify::Gpg
-  def self.me?(cask)
-    cask.gpg
-  end
+module Hbc
+  module Verify
+    class Gpg
+      def self.me?(cask)
+        cask.gpg
+      end
 
-  attr_reader :cask, :downloaded_path
+      attr_reader :cask, :downloaded_path
 
-  def initialize(cask, downloaded_path, command = Hbc::SystemCommand)
-    @command = command
-    @cask = cask
-    @downloaded_path = downloaded_path
-  end
+      def initialize(cask, downloaded_path, command = Hbc::SystemCommand)
+        @command = command
+        @cask = cask
+        @downloaded_path = downloaded_path
+      end
 
-  def available?
-    return @available unless @available.nil?
-    @available = self.class.me?(cask) && installed?
-  end
+      def available?
+        return @available unless @available.nil?
+        @available = self.class.me?(cask) && installed?
+      end
 
-  def installed?
-    cmd = @command.run("/usr/bin/type",
-                       args: ["-p", "gpg"])
+      def installed?
+        cmd = @command.run("/usr/bin/type",
+                           args: ["-p", "gpg"])
 
-    # if `gpg` is found, return its absolute path
-    cmd.success? ? cmd.stdout : false
-  end
+        # if `gpg` is found, return its absolute path
+        cmd.success? ? cmd.stdout : false
+      end
 
-  def fetch_sig(force = false)
-    unversioned_cask = cask.version.is_a?(Symbol)
-    cached = cask.metadata_subdir("gpg") unless unversioned_cask
+      def fetch_sig(force = false)
+        unversioned_cask = cask.version.is_a?(Symbol)
+        cached = cask.metadata_subdir("gpg") unless unversioned_cask
 
-    meta_dir = cached || cask.metadata_subdir("gpg", :now, true)
-    sig_path = meta_dir.join("signature.asc")
+        meta_dir = cached || cask.metadata_subdir("gpg", :now, true)
+        sig_path = meta_dir.join("signature.asc")
 
-    curl(cask.gpg.signature, "-o", sig_path.to_s) unless cached || force
+        curl(cask.gpg.signature, "-o", sig_path.to_s) unless cached || force
 
-    sig_path
-  end
+        sig_path
+      end
 
-  def import_key
-    args = if cask.gpg.key_id
-             ["--recv-keys", cask.gpg.key_id]
-           elsif cask.gpg.key_url
-             ["--fetch-key", cask.gpg.key_url.to_s]
-           end
+      def import_key
+        args = if cask.gpg.key_id
+                 ["--recv-keys", cask.gpg.key_id]
+               elsif cask.gpg.key_url
+                 ["--fetch-key", cask.gpg.key_url.to_s]
+               end
 
-    @command.run!("gpg", args: args)
-  end
+        @command.run!("gpg", args: args)
+      end
 
-  def verify
-    return unless available?
-    import_key
-    sig = fetch_sig
+      def verify
+        return unless available?
+        import_key
+        sig = fetch_sig
 
-    ohai "Verifying GPG signature for #{cask}"
+        ohai "Verifying GPG signature for #{cask}"
 
-    @command.run!("gpg",
-                  args:         ["--verify", sig, downloaded_path],
-                  print_stdout: true)
+        @command.run!("gpg",
+                      args:         ["--verify", sig, downloaded_path],
+                      print_stdout: true)
+      end
+    end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/without_source.rb b/Library/Homebrew/cask/lib/hbc/without_source.rb
index 6ed826e41..69131d5c7 100644
--- a/Library/Homebrew/cask/lib/hbc/without_source.rb
+++ b/Library/Homebrew/cask/lib/hbc/without_source.rb
@@ -1,15 +1,17 @@
-class Hbc::WithoutSource < Hbc::Cask
-  # Override from `Hbc::DSL` because we don't have a cask source file to work
-  # with, so we don't know the cask's `version`.
-  def staged_path
-    (caskroom_path.children - [metadata_master_container_path]).first
-  end
+module Hbc
+  class WithoutSource < Cask
+    # Override from `Hbc::DSL` because we don't have a cask source file to work
+    # with, so we don't know the cask's `version`.
+    def staged_path
+      (caskroom_path.children - [metadata_master_container_path]).first
+    end
 
-  def to_s
-    "#{token} (!)"
-  end
+    def to_s
+      "#{token} (!)"
+    end
 
-  def installed?
-    caskroom_path.exist?
+    def installed?
+      caskroom_path.exist?
+    end
   end
 end
diff --git a/Library/Homebrew/cask/spec/cask/cli/cleanup_spec.rb b/Library/Homebrew/cask/spec/cask/cli/cleanup_spec.rb
index ab2cd55cc..fe8bb2d4d 100644
--- a/Library/Homebrew/cask/spec/cask/cli/cleanup_spec.rb
+++ b/Library/Homebrew/cask/spec/cask/cli/cleanup_spec.rb
@@ -12,7 +12,7 @@ describe Hbc::CLI::Cleanup do
 
   describe "cleanup" do
     it "removes cached downloads of given casks" do
-      cleaned_up_cached_download = 'caffeine'
+      cleaned_up_cached_download = "caffeine"
 
       cached_downloads = [
                            cache_location.join("#{cleaned_up_cached_download}--latest.zip"),
diff --git a/Library/Homebrew/cask/spec/spec_helper.rb b/Library/Homebrew/cask/spec/spec_helper.rb
index 6bb13bdcf..aff214745 100644
--- a/Library/Homebrew/cask/spec/spec_helper.rb
+++ b/Library/Homebrew/cask/spec/spec_helper.rb
@@ -4,13 +4,12 @@ require "rspec/wait"
 
 if ENV["HOMEBREW_TESTS_COVERAGE"]
   require "simplecov"
-  SimpleCov.command_name "test:cask:rspec"
 end
 
 project_root = Pathname.new(File.expand_path("../..", __FILE__))
 
 # add Homebrew to load path
-$LOAD_PATH.unshift(File.expand_path("#{ENV['HOMEBREW_REPOSITORY']}/Library/Homebrew"))
+$LOAD_PATH.unshift(File.expand_path("#{ENV["HOMEBREW_REPOSITORY"]}/Library/Homebrew"))
 
 require "global"
 
@@ -30,7 +29,9 @@ require "mocha/api"
 
 require "hbc"
 
-class Hbc::TestCask < Hbc::Cask; end
+module Hbc
+  class TestCask < Cask; end
+end
 
 TEST_TMPDIR = Dir.mktmpdir("homebrew_cask_tests")
 at_exit do
diff --git a/Library/Homebrew/cask/spec/support/Casks/.rubocop.yml b/Library/Homebrew/cask/spec/support/Casks/.rubocop.yml
deleted file mode 120000
index ee5c2b948..000000000
--- a/Library/Homebrew/cask/spec/support/Casks/.rubocop.yml
+++ /dev/null
@@ -1 +0,0 @@
-../../../Casks/.rubocop.yml
\ No newline at end of file
diff --git a/Library/Homebrew/cask/test/cask/accessibility_test.rb b/Library/Homebrew/cask/test/cask/accessibility_test.rb
index ee192b4cb..8da8937fe 100644
--- a/Library/Homebrew/cask/test/cask/accessibility_test.rb
+++ b/Library/Homebrew/cask/test/cask/accessibility_test.rb
@@ -22,8 +22,7 @@ describe "Accessibility Access" do
         @installer.enable_accessibility_access
       end
     end
-
-    it "can enable accessibility access in OS X releases prior to Mavericks" do
+    it "can enable accessibility access in macOS releases prior to Mavericks" do
       MacOS.stubs(version: MacOS::Version.new("10.8"))
 
       Hbc::FakeSystemCommand.expects_command(
@@ -33,6 +32,14 @@ describe "Accessibility Access" do
         @installer.enable_accessibility_access
       end
     end
+    it "warns about enabling accessibility access on new macOS releases" do
+      MacOS.stubs(version: MacOS::Version.new("10.12"))
+
+      @installer.stubs(bundle_identifier: "com.example.BasicCask")
+
+      capture_io { @installer.enable_accessibility_access }[1]
+        .must_match("Warning: Accessibility access cannot be enabled automatically on this version of macOS.")
+    end
   end
 
   describe "uninstall" do
@@ -48,13 +55,21 @@ describe "Accessibility Access" do
         @installer.disable_accessibility_access
       end
     end
-    it "warns about disabling accessibility access on old OS X releases" do
+    it "warns about disabling accessibility access on old macOS releases" do
       MacOS.stubs(version: MacOS::Version.new("10.8"))
 
       @installer.stubs(bundle_identifier: "com.example.BasicCask")
 
       capture_io { @installer.disable_accessibility_access }[1]
-        .must_match("Warning: Accessibility access was enabled for with-accessibility-access, but it is not safe to disable")
+        .must_match("Warning: Accessibility access cannot be disabled automatically on this version of macOS.")
+    end
+    it "warns about disabling accessibility access on new macOS releases" do
+      MacOS.stubs(version: MacOS::Version.new("10.12"))
+
+      @installer.stubs(bundle_identifier: "com.example.BasicCask")
+
+      capture_io { @installer.disable_accessibility_access }[1]
+        .must_match("Warning: Accessibility access cannot be disabled automatically on this version of macOS.")
     end
   end
 end
diff --git a/Library/Homebrew/cask/test/cask/artifact/two_apps_correct_test.rb b/Library/Homebrew/cask/test/cask/artifact/two_apps_correct_test.rb
index afa4a61aa..47408ab9f 100644
--- a/Library/Homebrew/cask/test/cask/artifact/two_apps_correct_test.rb
+++ b/Library/Homebrew/cask/test/cask/artifact/two_apps_correct_test.rb
@@ -60,7 +60,6 @@ describe Hbc::Artifact::App do
       File.exist?(cask.staged_path.join("Caffeine Deluxe.app")).must_equal true
     end
 
-
     describe "avoids clobbering an existing app" do
       let(:cask) { local_two_apps_caffeine }
 
@@ -70,8 +69,8 @@ describe Hbc::Artifact::App do
         TestHelper.must_output(self, lambda {
           Hbc::Artifact::App.new(cask).install_phase
         }, <<-EOS.undent.chomp)
-             ==> It seems there is already an App at '#{Hbc.appdir.join('Caffeine Mini.app')}'; not moving.
-             ==> Moving App 'Caffeine Pro.app' to '#{Hbc.appdir.join('Caffeine Pro.app')}'
+             ==> It seems there is already an App at '#{Hbc.appdir.join("Caffeine Mini.app")}'; not moving.
+             ==> Moving App 'Caffeine Pro.app' to '#{Hbc.appdir.join("Caffeine Pro.app")}'
            EOS
 
         source_path = cask.staged_path.join("Caffeine Mini.app")
@@ -85,8 +84,8 @@ describe Hbc::Artifact::App do
         TestHelper.must_output(self, lambda {
           Hbc::Artifact::App.new(cask).install_phase
         }, <<-EOS.undent.chomp)
-             ==> Moving App 'Caffeine Mini.app' to '#{Hbc.appdir.join('Caffeine Mini.app')}'
-             ==> It seems there is already an App at '#{Hbc.appdir.join('Caffeine Pro.app')}'; not moving.
+             ==> Moving App 'Caffeine Mini.app' to '#{Hbc.appdir.join("Caffeine Mini.app")}'
+             ==> It seems there is already an App at '#{Hbc.appdir.join("Caffeine Pro.app")}'; not moving.
            EOS
 
         source_path = cask.staged_path.join("Caffeine Pro.app")
diff --git a/Library/Homebrew/cask/test/cask/cli/create_test.rb b/Library/Homebrew/cask/test/cask/cli/create_test.rb
index cf3cf28a3..efca1a506 100644
--- a/Library/Homebrew/cask/test/cask/cli/create_test.rb
+++ b/Library/Homebrew/cask/test/cask/cli/create_test.rb
@@ -1,17 +1,21 @@
 require "test_helper"
 
 # monkeypatch for testing
-class Hbc::CLI::Create
-  def self.exec_editor(*command)
-    editor_commands << command
-  end
+module Hbc
+  class CLI
+    class Create
+      def self.exec_editor(*command)
+        editor_commands << command
+      end
 
-  def self.reset!
-    @editor_commands = []
-  end
+      def self.reset!
+        @editor_commands = []
+      end
 
-  def self.editor_commands
-    @editor_commands ||= []
+      def self.editor_commands
+        @editor_commands ||= []
+      end
+    end
   end
 end
 
diff --git a/Library/Homebrew/cask/test/cask/cli/edit_test.rb b/Library/Homebrew/cask/test/cask/cli/edit_test.rb
index ebec5f414..3f385eb33 100644
--- a/Library/Homebrew/cask/test/cask/cli/edit_test.rb
+++ b/Library/Homebrew/cask/test/cask/cli/edit_test.rb
@@ -1,17 +1,21 @@
 require "test_helper"
 
 # monkeypatch for testing
-class Hbc::CLI::Edit
-  def self.exec_editor(*command)
-    editor_commands << command
-  end
-
-  def self.reset!
-    @editor_commands = []
-  end
-
-  def self.editor_commands
-    @editor_commands ||= []
+module Hbc
+  class CLI
+    class Edit
+      def self.exec_editor(*command)
+        editor_commands << command
+      end
+
+      def self.reset!
+        @editor_commands = []
+      end
+
+      def self.editor_commands
+        @editor_commands ||= []
+      end
+    end
   end
 end
 
diff --git a/Library/Homebrew/cask/test/cask/cli/home_test.rb b/Library/Homebrew/cask/test/cask/cli/home_test.rb
index 28fd2a391..78302abd1 100644
--- a/Library/Homebrew/cask/test/cask/cli/home_test.rb
+++ b/Library/Homebrew/cask/test/cask/cli/home_test.rb
@@ -1,17 +1,21 @@
 require "test_helper"
 
 # monkeypatch for testing
-class Hbc::CLI::Home
-  def self.system(*command)
-    system_commands << command
-  end
+module Hbc
+  class CLI
+    class Home
+      def self.system(*command)
+        system_commands << command
+      end
 
-  def self.reset!
-    @system_commands = []
-  end
+      def self.reset!
+        @system_commands = []
+      end
 
-  def self.system_commands
-    @system_commands ||= []
+      def self.system_commands
+        @system_commands ||= []
+      end
+    end
   end
 end
 
diff --git a/Library/Homebrew/cask/test/cask/cli/list_test.rb b/Library/Homebrew/cask/test/cask/cli/list_test.rb
index 2189498d4..6831bf0a4 100644
--- a/Library/Homebrew/cask/test/cask/cli/list_test.rb
+++ b/Library/Homebrew/cask/test/cask/cli/list_test.rb
@@ -79,9 +79,9 @@ describe Hbc::CLI::List do
         Hbc::CLI::List.run("local-transmission", "local-caffeine")
       }.must_output <<-EOS.undent
       ==> Apps
-      #{Hbc.appdir.join('Transmission.app')} (#{Hbc.appdir.join('Transmission.app').abv})
+      #{Hbc.appdir.join("Transmission.app")} (#{Hbc.appdir.join("Transmission.app").abv})
       ==> Apps
-      Missing App: #{Hbc.appdir.join('Caffeine.app')}
+      Missing App: #{Hbc.appdir.join("Caffeine.app")}
     EOS
     end
   end
diff --git a/Library/Homebrew/cask/test/support/Casks/.rubocop.yml b/Library/Homebrew/cask/test/support/Casks/.rubocop.yml
deleted file mode 120000
index ee5c2b948..000000000
--- a/Library/Homebrew/cask/test/support/Casks/.rubocop.yml
+++ /dev/null
@@ -1 +0,0 @@
-../../../Casks/.rubocop.yml
\ No newline at end of file
diff --git a/Library/Homebrew/cask/test/support/cleanup.rb b/Library/Homebrew/cask/test/support/cleanup.rb
index 0cb9c02fa..c31a74be2 100644
--- a/Library/Homebrew/cask/test/support/cleanup.rb
+++ b/Library/Homebrew/cask/test/support/cleanup.rb
@@ -1,12 +1,10 @@
-module Hbc::CleanupHooks
-  def after_teardown
-    super
-    Hbc.installed.each do |cask|
-      Hbc::Installer.new(cask).purge_versioned_files
+module MiniTest
+  class Spec
+    def after_teardown
+      super
+      Hbc.installed.each do |cask|
+        Hbc::Installer.new(cask).purge_versioned_files
+      end
     end
   end
 end
-
-class MiniTest::Spec
-  include Hbc::CleanupHooks
-end
diff --git a/Library/Homebrew/cask/test/support/fake_dirs.rb b/Library/Homebrew/cask/test/support/fake_dirs.rb
index 89612f850..f8e36bbbb 100644
--- a/Library/Homebrew/cask/test/support/fake_dirs.rb
+++ b/Library/Homebrew/cask/test/support/fake_dirs.rb
@@ -24,6 +24,8 @@ module FakeDirHooks
   end
 end
 
-class MiniTest::Spec
-  include FakeDirHooks
+module MiniTest
+  class Spec
+    include FakeDirHooks
+  end
 end
diff --git a/Library/Homebrew/cask/test/support/fake_fetcher.rb b/Library/Homebrew/cask/test/support/fake_fetcher.rb
index a49a89f7f..43483751f 100644
--- a/Library/Homebrew/cask/test/support/fake_fetcher.rb
+++ b/Library/Homebrew/cask/test/support/fake_fetcher.rb
@@ -1,20 +1,22 @@
-class Hbc::FakeFetcher
-  def self.fake_response_for(url, response)
-    @responses[url] = response
-  end
+module Hbc
+  class FakeFetcher
+    def self.fake_response_for(url, response)
+      @responses[url] = response
+    end
 
-  def self.head(url)
-    @responses ||= {}
-    raise("no response faked for #{url.inspect}") unless @responses.key?(url)
-    @responses[url]
-  end
+    def self.head(url)
+      @responses ||= {}
+      raise("no response faked for #{url.inspect}") unless @responses.key?(url)
+      @responses[url]
+    end
 
-  def self.init
-    @responses = {}
-  end
+    def self.init
+      @responses = {}
+    end
 
-  def self.clear
-    @responses = {}
+    def self.clear
+      @responses = {}
+    end
   end
 end
 
@@ -30,6 +32,8 @@ module FakeFetcherHooks
   end
 end
 
-class MiniTest::Spec
-  include FakeFetcherHooks
+module MiniTest
+  class Spec
+    include FakeFetcherHooks
+  end
 end
diff --git a/Library/Homebrew/cask/test/support/fake_system_command.rb b/Library/Homebrew/cask/test/support/fake_system_command.rb
index e19330fd0..97efd0761 100644
--- a/Library/Homebrew/cask/test/support/fake_system_command.rb
+++ b/Library/Homebrew/cask/test/support/fake_system_command.rb
@@ -1,61 +1,63 @@
-class Hbc::FakeSystemCommand
-  def self.responses
-    @responses ||= {}
-  end
+module Hbc
+  class FakeSystemCommand
+    def self.responses
+      @responses ||= {}
+    end
 
-  def self.expectations
-    @expectations ||= {}
-  end
+    def self.expectations
+      @expectations ||= {}
+    end
 
-  def self.system_calls
-    @system_calls ||= Hash.new(0)
-  end
+    def self.system_calls
+      @system_calls ||= Hash.new(0)
+    end
 
-  def self.clear
-    @responses    = nil
-    @expectations = nil
-    @system_calls = nil
-  end
+    def self.clear
+      @responses    = nil
+      @expectations = nil
+      @system_calls = nil
+    end
 
-  def self.stubs_command(command, response = "")
-    responses[command] = response
-  end
+    def self.stubs_command(command, response = "")
+      responses[command] = response
+    end
 
-  def self.expects_command(command, response = "", times = 1)
-    stubs_command(command, response)
-    expectations[command] = times
-  end
+    def self.expects_command(command, response = "", times = 1)
+      stubs_command(command, response)
+      expectations[command] = times
+    end
 
-  def self.expect_and_pass_through(command, times = 1)
-    pass_through = ->(cmd, opts) { Hbc::SystemCommand.run(cmd, opts) }
-    expects_command(command, pass_through, times)
-  end
+    def self.expect_and_pass_through(command, times = 1)
+      pass_through = ->(cmd, opts) { Hbc::SystemCommand.run(cmd, opts) }
+      expects_command(command, pass_through, times)
+    end
 
-  def self.verify_expectations!
-    expectations.each do |command, times|
-      unless system_calls[command] == times
-        raise("expected #{command.inspect} to be run #{times} times, but got #{system_calls[command]}")
+    def self.verify_expectations!
+      expectations.each do |command, times|
+        unless system_calls[command] == times
+          raise("expected #{command.inspect} to be run #{times} times, but got #{system_calls[command]}")
+        end
       end
     end
-  end
 
-  def self.run(command_string, options = {})
-    command = Hbc::SystemCommand.new(command_string, options).command
-    unless responses.key?(command)
-      raise("no response faked for #{command.inspect}, faked responses are: #{responses.inspect}")
-    end
-    system_calls[command] += 1
+    def self.run(command_string, options = {})
+      command = Hbc::SystemCommand.new(command_string, options).command
+      unless responses.key?(command)
+        raise("no response faked for #{command.inspect}, faked responses are: #{responses.inspect}")
+      end
+      system_calls[command] += 1
 
-    response = responses[command]
-    if response.respond_to?(:call)
-      response.call(command_string, options)
-    else
-      Hbc::SystemCommand::Result.new(command, response, "", 0)
+      response = responses[command]
+      if response.respond_to?(:call)
+        response.call(command_string, options)
+      else
+        Hbc::SystemCommand::Result.new(command, response, "", 0)
+      end
     end
-  end
 
-  def self.run!(command, options = {})
-    run(command, options.merge(must_succeed: true))
+    def self.run!(command, options = {})
+      run(command, options.merge(must_succeed: true))
+    end
   end
 end
 
@@ -68,6 +70,8 @@ module FakeSystemCommandHooks
   end
 end
 
-class MiniTest::Spec
-  include FakeSystemCommandHooks
+module MiniTest
+  class Spec
+    include FakeSystemCommandHooks
+  end
 end
diff --git a/Library/Homebrew/cask/test/support/never_sudo_system_command.rb b/Library/Homebrew/cask/test/support/never_sudo_system_command.rb
index 50f510a7a..8a370df44 100644
--- a/Library/Homebrew/cask/test/support/never_sudo_system_command.rb
+++ b/Library/Homebrew/cask/test/support/never_sudo_system_command.rb
@@ -1,5 +1,7 @@
-class Hbc::NeverSudoSystemCommand < Hbc::SystemCommand
-  def self.run(command, options = {})
-    super(command, options.merge(sudo: false))
+module Hbc
+  class NeverSudoSystemCommand < SystemCommand
+    def self.run(command, options = {})
+      super(command, options.merge(sudo: false))
+    end
   end
 end
diff --git a/Library/Homebrew/cask/test/support/shared_examples.rb b/Library/Homebrew/cask/test/support/shared_examples.rb
index e846af404..594ca81c1 100644
--- a/Library/Homebrew/cask/test/support/shared_examples.rb
+++ b/Library/Homebrew/cask/test/support/shared_examples.rb
@@ -5,14 +5,18 @@ MiniTest::Spec.class_eval do
   end
 end
 
-module MiniTest::Spec::SharedExamples
-  def shared_examples_for(desc, &block)
-    MiniTest::Spec.shared_examples[desc] = block
-  end
+module MiniTest
+  class Spec
+    module SharedExamples
+      def shared_examples_for(desc, &block)
+        MiniTest::Spec.shared_examples[desc] = block
+      end
 
-  def it_behaves_like(desc, *args, &block)
-    instance_exec(*args, &MiniTest::Spec.shared_examples[desc])
-    instance_eval(&block) if block_given?
+      def it_behaves_like(desc, *args, &block)
+        instance_exec(*args, &MiniTest::Spec.shared_examples[desc])
+        instance_eval(&block) if block_given?
+      end
+    end
   end
 end
 
diff --git a/Library/Homebrew/cask/test/test_helper.rb b/Library/Homebrew/cask/test/test_helper.rb
index e4fd72170..47c1b4cdb 100644
--- a/Library/Homebrew/cask/test/test_helper.rb
+++ b/Library/Homebrew/cask/test/test_helper.rb
@@ -4,14 +4,13 @@ require "pathname"
 
 if ENV["HOMEBREW_TESTS_COVERAGE"]
   require "simplecov"
-  SimpleCov.command_name "test:cask:minitest"
 end
 
 project_root = Pathname.new(File.expand_path("../..", __FILE__))
 tap_root = Pathname.new(ENV["HOMEBREW_LIBRARY"]).join("Taps", "caskroom", "homebrew-cask")
 
 # add Homebrew to load path
-$LOAD_PATH.unshift(File.expand_path("#{ENV['HOMEBREW_REPOSITORY']}/Library/Homebrew"))
+$LOAD_PATH.unshift(File.expand_path("#{ENV["HOMEBREW_REPOSITORY"]}/Library/Homebrew"))
 
 require "global"
 
@@ -39,6 +38,8 @@ require "minitest/autorun"
 require "minitest/reporters"
 Minitest::Reporters.use! Minitest::Reporters::DefaultReporter.new(color: true)
 
+require "parallel_tests/test/runtime_logger"
+
 # Force mocha to patch MiniTest since we have both loaded thanks to homebrew's testing_env
 require "mocha/api"
 require "mocha/integration/mini_test"
@@ -158,7 +159,9 @@ require "tempfile"
 FileUtils.mkdir_p Hbc.homebrew_prefix.join("bin")
 
 # Common superclass for test Casks for when we need to filter them out
-class Hbc::TestCask < Hbc::Cask; end
+module Hbc
+  class TestCask < Cask; end
+end
 
 # jack in some optional utilities
 FileUtils.ln_s "/usr/local/bin/cabextract", Hbc.homebrew_prefix.join("bin/cabextract")
diff --git a/Library/Homebrew/caveats.rb b/Library/Homebrew/caveats.rb
index 9c1787f87..a5568cb29 100644
--- a/Library/Homebrew/caveats.rb
+++ b/Library/Homebrew/caveats.rb
@@ -69,27 +69,34 @@ class Caveats
   end
 
   def bash_completion_caveats
-    if keg && keg.completion_installed?(:bash) then <<-EOS.undent
+    return unless keg
+    return unless keg.completion_installed?(:bash)
+
+    <<-EOS.undent
       Bash completion has been installed to:
         #{HOMEBREW_PREFIX}/etc/bash_completion.d
-      EOS
-    end
+    EOS
   end
 
   def zsh_completion_caveats
-    if keg && keg.completion_installed?(:zsh) then <<-EOS.undent
+    return unless keg
+    return unless keg.completion_installed?(:zsh)
+
+    <<-EOS.undent
       zsh completion has been installed to:
         #{HOMEBREW_PREFIX}/share/zsh/site-functions
-      EOS
-    end
+    EOS
   end
 
   def fish_completion_caveats
-    if keg && keg.completion_installed?(:fish) && which("fish") then <<-EOS.undent
+    return unless keg
+    return unless keg.completion_installed?(:fish)
+    return unless which("fish")
+
+    <<-EOS.undent
       fish completion has been installed to:
         #{HOMEBREW_PREFIX}/share/fish/vendor_completions.d
-      EOS
-    end
+    EOS
   end
 
   def python_caveats
@@ -140,22 +147,24 @@ class Caveats
   end
 
   def app_caveats
-    if keg && keg.app_installed?
-      <<-EOS.undent
-        .app bundles were installed.
-        Run `brew linkapps #{keg.name}` to symlink these to /Applications.
-      EOS
-    end
+    return unless keg
+    return unless keg.app_installed?
+
+    <<-EOS.undent
+      .app bundles were installed.
+      Run `brew linkapps #{keg.name}` to symlink these to /Applications.
+    EOS
   end
 
   def elisp_caveats
     return if f.keg_only?
-    if keg && keg.elisp_installed?
-      <<-EOS.undent
-        Emacs Lisp files have been installed to:
-          #{HOMEBREW_PREFIX}/share/emacs/site-lisp/#{f.name}
-      EOS
-    end
+    return unless keg
+    return unless keg.elisp_installed?
+
+    <<-EOS.undent
+      Emacs Lisp files have been installed to:
+        #{HOMEBREW_PREFIX}/share/emacs/site-lisp/#{f.name}
+    EOS
   end
 
   def plist_caveats
diff --git a/Library/Homebrew/checksum.rb b/Library/Homebrew/checksum.rb
index 6be454efb..1b095ea32 100644
--- a/Library/Homebrew/checksum.rb
+++ b/Library/Homebrew/checksum.rb
@@ -1,6 +1,6 @@
 class Checksum
   attr_reader :hash_type, :hexdigest
-  alias_method :to_s, :hexdigest
+  alias to_s hexdigest
 
   TYPES = [:sha256].freeze
 
diff --git a/Library/Homebrew/cleaner.rb b/Library/Homebrew/cleaner.rb
index d8a998576..7456e18d6 100644
--- a/Library/Homebrew/cleaner.rb
+++ b/Library/Homebrew/cleaner.rb
@@ -87,9 +87,9 @@ class Cleaner
 
       Find.prune if @f.skip_clean? path
 
-      if path.symlink? || path.directory?
-        next
-      elsif path.extname == ".la"
+      next if path.symlink? || path.directory?
+
+      if path.extname == ".la"
         path.unlink
       elsif path.basename.to_s == "perllocal.pod"
         # Both this file & the .packlist one below are completely unnecessary
diff --git a/Library/Homebrew/cleanup.rb b/Library/Homebrew/cleanup.rb
index 265f06d26..04a976e55 100644
--- a/Library/Homebrew/cleanup.rb
+++ b/Library/Homebrew/cleanup.rb
@@ -12,7 +12,7 @@ module Homebrew
       cleanup_logs
       unless ARGV.dry_run?
         cleanup_lockfiles
-        rm_DS_Store
+        rm_ds_store
       end
     end
 
@@ -66,7 +66,7 @@ module Homebrew
         next unless path.file?
         file = path
 
-        if Pathname::BOTTLE_EXTNAME_RX === file.to_s
+        if file.to_s =~ Pathname::BOTTLE_EXTNAME_RX
           version = begin
                       Utils::Bottles.resolve_version(file)
                     rescue
@@ -86,7 +86,7 @@ module Homebrew
           next
         end
 
-        file_is_stale = if PkgVersion === version
+        file_is_stale = if version.is_a?(PkgVersion)
           f.pkg_version > version
         else
           f.version > version
@@ -119,7 +119,7 @@ module Homebrew
       end
     end
 
-    def self.rm_DS_Store
+    def self.rm_ds_store
       paths = Queue.new
       %w[Cellar Frameworks Library bin etc include lib opt sbin share var]
         .map { |p| HOMEBREW_PREFIX/p }.each { |p| paths << p if p.exist? }
diff --git a/Library/Homebrew/cmd/cleanup.rb b/Library/Homebrew/cmd/cleanup.rb
index a9d3fbcde..6e0915c9a 100644
--- a/Library/Homebrew/cmd/cleanup.rb
+++ b/Library/Homebrew/cmd/cleanup.rb
@@ -22,13 +22,13 @@ module Homebrew
       ARGV.resolved_formulae.each { |f| Cleanup.cleanup_formula f }
     end
 
-    if Cleanup.disk_cleanup_size > 0
-      disk_space = disk_usage_readable(Cleanup.disk_cleanup_size)
-      if ARGV.dry_run?
-        ohai "This operation would free approximately #{disk_space} of disk space."
-      else
-        ohai "This operation has freed approximately #{disk_space} of disk space."
-      end
+    return if Cleanup.disk_cleanup_size.zero?
+
+    disk_space = disk_usage_readable(Cleanup.disk_cleanup_size)
+    if ARGV.dry_run?
+      ohai "This operation would free approximately #{disk_space} of disk space."
+    else
+      ohai "This operation has freed approximately #{disk_space} of disk space."
     end
   end
 end
diff --git a/Library/Homebrew/cmd/diy.rb b/Library/Homebrew/cmd/diy.rb
index 8262352f8..95ec7fe35 100644
--- a/Library/Homebrew/cmd/diy.rb
+++ b/Library/Homebrew/cmd/diy.rb
@@ -31,11 +31,9 @@ module Homebrew
   def detect_version(path)
     version = path.version.to_s
 
-    if version.empty?
-      raise "Couldn't determine version, set it with --version=<version>"
-    else
-      version
-    end
+    raise "Couldn't determine version, set it with --version=<version>" if version.empty?
+
+    version
   end
 
   def detect_name(path, version)
diff --git a/Library/Homebrew/cmd/info.rb b/Library/Homebrew/cmd/info.rb
index 2474aad57..09c832203 100644
--- a/Library/Homebrew/cmd/info.rb
+++ b/Library/Homebrew/cmd/info.rb
@@ -54,11 +54,8 @@ module Homebrew
           end
         rescue FormulaUnavailableError
           # No formula with this name, try a blacklist lookup
-          if (blacklist = blacklisted?(f))
-            puts blacklist
-          else
-            raise
-          end
+          raise unless (blacklist = blacklisted?(f))
+          puts blacklist
         end
       end
     end
diff --git a/Library/Homebrew/cmd/install.rb b/Library/Homebrew/cmd/install.rb
index 50439ccf9..8a8323252 100644
--- a/Library/Homebrew/cmd/install.rb
+++ b/Library/Homebrew/cmd/install.rb
@@ -203,13 +203,12 @@ module Homebrew
         # If they haven't updated in 48 hours (172800 seconds), that
         # might explain the error
         master = HOMEBREW_REPOSITORY/".git/refs/heads/master"
-        if master.exist? && (Time.now.to_i - File.mtime(master).to_i) > 172800
-          ohai "You haven't updated Homebrew in a while."
-          puts <<-EOS.undent
-            A formula for #{e.name} might have been added recently.
-            Run `brew update` to get the latest Homebrew updates!
-          EOS
-        end
+        return unless master.exist? && (Time.now.to_i - File.mtime(master).to_i) > 172800
+        ohai "You haven't updated Homebrew in a while."
+        puts <<-EOS.undent
+          A formula for #{e.name} might have been added recently.
+          Run `brew update` to get the latest Homebrew updates!
+        EOS
       end
     end
   end
@@ -245,11 +244,11 @@ module Homebrew
   end
 
   def check_macports
-    unless MacOS.macports_or_fink.empty?
-      opoo "It appears you have MacPorts or Fink installed."
-      puts "Software installed with other package managers causes known problems for"
-      puts "Homebrew. If a formula fails to build, uninstall MacPorts/Fink and try again."
-    end
+    return if MacOS.macports_or_fink.empty?
+
+    opoo "It appears you have MacPorts or Fink installed."
+    puts "Software installed with other package managers causes known problems for"
+    puts "Homebrew. If a formula fails to build, uninstall MacPorts/Fink and try again."
   end
 
   def check_cellar
diff --git a/Library/Homebrew/cmd/postinstall.rb b/Library/Homebrew/cmd/postinstall.rb
index 71b71b3f5..e0bd8e31b 100644
--- a/Library/Homebrew/cmd/postinstall.rb
+++ b/Library/Homebrew/cmd/postinstall.rb
@@ -36,7 +36,7 @@ module Homebrew
         sandbox.allow_write_cellar(formula)
         sandbox.allow_write_xcode
         sandbox.allow_write_path HOMEBREW_PREFIX
-        sandbox.deny_write_homebrew_library
+        sandbox.deny_write_homebrew_repository
         sandbox.exec(*args)
       else
         exec(*args)
diff --git a/Library/Homebrew/cmd/reinstall.rb b/Library/Homebrew/cmd/reinstall.rb
index e51aace2a..bda6022bf 100644
--- a/Library/Homebrew/cmd/reinstall.rb
+++ b/Library/Homebrew/cmd/reinstall.rb
@@ -58,10 +58,11 @@ module Homebrew
 
   def restore_backup(keg, formula)
     path = backup_path(keg)
-    if path.directory?
-      path.rename keg
-      keg.link unless formula.keg_only?
-    end
+
+    return unless path.directory?
+
+    path.rename keg
+    keg.link unless formula.keg_only?
   end
 
   def backup_path(path)
diff --git a/Library/Homebrew/cmd/search.rb b/Library/Homebrew/cmd/search.rb
index 50d9f5f74..aa80ec589 100644
--- a/Library/Homebrew/cmd/search.rb
+++ b/Library/Homebrew/cmd/search.rb
@@ -150,7 +150,7 @@ module Homebrew
 
     names = remote_tap_formulae["#{user}/#{repo}"]
     user = user.downcase if user == "Homebrew" # special handling for the Homebrew organization
-    names.select { |name| rx === name }.map { |name| "#{user}/#{repo}/#{name}" }
+    names.select { |name| name =~ rx }.map { |name| "#{user}/#{repo}/#{name}" }
   rescue GitHub::HTTPNotFoundError
     opoo "Failed to search tap: #{user}/#{repo}. Please run `brew update`"
     []
@@ -171,10 +171,11 @@ module Homebrew
       rescue
         canonical_name = canonical_full_name = name
       end
+
       # Ignore aliases from results when the full name was also found
-      if aliases.include?(name) && results.include?(canonical_full_name)
-        next
-      elsif (HOMEBREW_CELLAR/canonical_name).directory?
+      next if aliases.include?(name) && results.include?(canonical_full_name)
+
+      if (HOMEBREW_CELLAR/canonical_name).directory?
         pretty_installed(name)
       else
         name
diff --git a/Library/Homebrew/cmd/style.rb b/Library/Homebrew/cmd/style.rb
index f28d50cc1..db61116be 100644
--- a/Library/Homebrew/cmd/style.rb
+++ b/Library/Homebrew/cmd/style.rb
@@ -45,7 +45,7 @@ module Homebrew
 
   def check_style_impl(files, output_type, options = {})
     fix = options[:fix]
-    Homebrew.install_gem_setup_path! "rubocop", "0.41.2"
+    Homebrew.install_gem_setup_path! "rubocop", "0.43.0"
 
     args = %W[
       --force-exclusion
@@ -54,20 +54,22 @@ module Homebrew
     args << "--auto-correct" if fix
     args += files
 
-    case output_type
-    when :print
-      args << "--display-cop-names" if ARGV.include? "--display-cop-names"
-      system "rubocop", "--format", "simple", *args
-      !$?.success?
-    when :json
-      json = Utils.popen_read_text("rubocop", "--format", "json", *args)
-      # exit status of 1 just means violations were found; other numbers mean execution errors
-      # exitstatus can also be nil if RuboCop process crashes, e.g. due to
-      # native extension problems
-      raise "Error while running RuboCop" if $?.exitstatus.nil? || $?.exitstatus > 1
-      RubocopResults.new(Utils::JSON.load(json))
-    else
-      raise "Invalid output_type for check_style_impl: #{output_type}"
+    HOMEBREW_LIBRARY.cd do
+      case output_type
+      when :print
+        args << "--display-cop-names" if ARGV.include? "--display-cop-names"
+        system "rubocop", "--format", "simple", *args
+        !$?.success?
+      when :json
+        json = Utils.popen_read_text("rubocop", "--format", "json", *args)
+        # exit status of 1 just means violations were found; other numbers mean execution errors
+        # exitstatus can also be nil if RuboCop process crashes, e.g. due to
+        # native extension problems
+        raise "Error while running RuboCop" if $?.exitstatus.nil? || $?.exitstatus > 1
+        RubocopResults.new(Utils::JSON.load(json))
+      else
+        raise "Invalid output_type for check_style_impl: #{output_type}"
+      end
     end
   end
 
diff --git a/Library/Homebrew/cmd/uninstall.rb b/Library/Homebrew/cmd/uninstall.rb
index 6ea45a770..f4ca8ff87 100644
--- a/Library/Homebrew/cmd/uninstall.rb
+++ b/Library/Homebrew/cmd/uninstall.rb
@@ -25,7 +25,7 @@ module Homebrew
             versions = rack.subdirs.map(&:basename)
             verb = versions.length == 1 ? "is" : "are"
             puts "#{keg.name} #{versions.join(", ")} #{verb} still installed."
-            puts "Remove them all with `brew uninstall --force #{keg.name}`."
+            puts "Remove all versions with `brew uninstall --force #{keg.name}`."
           end
         end
       end
diff --git a/Library/Homebrew/cmd/update-report.rb b/Library/Homebrew/cmd/update-report.rb
index 1e9c8ccd3..18f2f370c 100644
--- a/Library/Homebrew/cmd/update-report.rb
+++ b/Library/Homebrew/cmd/update-report.rb
@@ -549,11 +549,10 @@ class ReporterHub
       end
     end
 
-    unless formulae.empty?
-      # Dump formula list.
-      ohai title
-      puts_columns(formulae)
-    end
+    return if formulae.empty?
+    # Dump formula list.
+    ohai title
+    puts_columns(formulae)
   end
 
   def installed?(formula)
diff --git a/Library/Homebrew/cmd/update.sh b/Library/Homebrew/cmd/update.sh
index b57691893..579890820 100644
--- a/Library/Homebrew/cmd/update.sh
+++ b/Library/Homebrew/cmd/update.sh
@@ -215,7 +215,20 @@ merge_or_rebase() {
 
   trap reset_on_interrupt SIGINT
 
-  REMOTE_REF="origin/$UPSTREAM_BRANCH"
+  if [[ "$DIR" = "$HOMEBREW_REPOSITORY" && -z "$HOMEBREW_NO_UPDATE_CLEANUP" ]]
+  then
+    UPSTREAM_TAG="$(git tag --list --sort=-version:refname | grep '^[0-9]*\.[0-9]*\.[0-9]*$' | head -n1)"
+  else
+    UPSTREAM_TAG=""
+  fi
+
+  if [ -n "$UPSTREAM_TAG" ]
+  then
+    REMOTE_REF="refs/tags/$UPSTREAM_TAG"
+    UPSTREAM_BRANCH="stable"
+  else
+    REMOTE_REF="origin/$UPSTREAM_BRANCH"
+  fi
 
   if [[ -n "$(git status --untracked-files=all --porcelain 2>/dev/null)" ]]
   then
@@ -242,19 +255,13 @@ EOS
   fi
 
   INITIAL_BRANCH="$(git symbolic-ref --short HEAD 2>/dev/null)"
-  if [[ "$INITIAL_BRANCH" != "$UPSTREAM_BRANCH" && -n "$INITIAL_BRANCH" ]]
+  if [[ -n "$UPSTREAM_TAG" ]] ||
+     [[ "$INITIAL_BRANCH" != "$UPSTREAM_BRANCH" && -n "$INITIAL_BRANCH" ]]
   then
-
-    if [[ -z "$HOMEBREW_NO_UPDATE_CLEANUP" ]]
-    then
-      echo "Checking out $UPSTREAM_BRANCH in $DIR..."
-      echo "To checkout $INITIAL_BRANCH in $DIR run:"
-      echo "  'cd $DIR && git checkout $INITIAL_BRANCH"
-    fi
-
     # Recreate and check out `#{upstream_branch}` if unable to fast-forward
     # it to `origin/#{@upstream_branch}`. Otherwise, just check it out.
-    if git merge-base --is-ancestor "$UPSTREAM_BRANCH" "$REMOTE_REF" &>/dev/null
+    if [[ -z "$UPSTREAM_TAG" ]] &&
+       git merge-base --is-ancestor "$UPSTREAM_BRANCH" "$REMOTE_REF" &>/dev/null
     then
       git checkout --force "$UPSTREAM_BRANCH" "${QUIET_ARGS[@]}"
     else
@@ -290,7 +297,8 @@ EOS
 
   if [[ -n "$HOMEBREW_NO_UPDATE_CLEANUP" ]]
   then
-    if [[ "$INITIAL_BRANCH" != "$UPSTREAM_BRANCH" && -n "$INITIAL_BRANCH" ]]
+    if [[ "$INITIAL_BRANCH" != "$UPSTREAM_BRANCH" && -n "$INITIAL_BRANCH" &&
+          ! "$INITIAL_BRANCH" =~ ^v[0-9]+\.[0-9]+\.[0-9]$ ]]
     then
       git checkout "$INITIAL_BRANCH" "${QUIET_ARGS[@]}"
     fi
@@ -337,7 +345,7 @@ EOS
     set -x
   fi
 
-  if [[ -z "$HOMEBREW_UPDATE_CLEANUP" ]]
+  if [[ -z "$HOMEBREW_UPDATE_CLEANUP" && -z "$HOMEBREW_UPDATE_TO_TAG" ]]
   then
     if [[ -n "$HOMEBREW_DEVELOPER" || -n "$HOMEBREW_DEV_CMD_RUN" ]]
     then
@@ -425,6 +433,12 @@ EOS
     declare UPSTREAM_BRANCH"$TAP_VAR"="$UPSTREAM_BRANCH_DIR"
     declare PREFETCH_REVISION"$TAP_VAR"="$(git rev-parse -q --verify refs/remotes/origin/"$UPSTREAM_BRANCH_DIR")"
 
+    # Force a full update if we don't have any tags.
+    if [[ "$DIR" = "$HOMEBREW_REPOSITORY" && -z "$(git tag --list)" ]]
+    then
+      HOMEBREW_UPDATE_FORCE=1
+    fi
+
     if [[ -z "$HOMEBREW_UPDATE_FORCE" ]]
     then
       [[ -n "$SKIP_FETCH_BREW_REPOSITORY" && "$DIR" = "$HOMEBREW_REPOSITORY" ]] && continue
@@ -480,10 +494,10 @@ EOS
 
       if [[ -n "$HOMEBREW_UPDATE_PREINSTALL" ]]
       then
-        git fetch --force "${QUIET_ARGS[@]}" origin \
+        git fetch --tags --force "${QUIET_ARGS[@]}" origin \
           "refs/heads/$UPSTREAM_BRANCH_DIR:refs/remotes/origin/$UPSTREAM_BRANCH_DIR" 2>/dev/null
       else
-        if ! git fetch --force "${QUIET_ARGS[@]}" origin \
+        if ! git fetch --tags --force "${QUIET_ARGS[@]}" origin \
           "refs/heads/$UPSTREAM_BRANCH_DIR:refs/remotes/origin/$UPSTREAM_BRANCH_DIR"
         then
           echo "Fetching $DIR failed!" >>"$update_failed_file"
diff --git a/Library/Homebrew/compat/dependency_collector.rb b/Library/Homebrew/compat/dependency_collector.rb
index 27236ae4b..b18adc490 100644
--- a/Library/Homebrew/compat/dependency_collector.rb
+++ b/Library/Homebrew/compat/dependency_collector.rb
@@ -1,7 +1,7 @@
 require "dependency_collector"
 
 class DependencyCollector
-  alias_method :_parse_symbol_spec, :parse_symbol_spec
+  alias _parse_symbol_spec parse_symbol_spec
 
   def parse_symbol_spec(spec, tags)
     case spec
diff --git a/Library/Homebrew/compat/formula.rb b/Library/Homebrew/compat/formula.rb
index 41896d261..853a38706 100644
--- a/Library/Homebrew/compat/formula.rb
+++ b/Library/Homebrew/compat/formula.rb
@@ -72,8 +72,8 @@ class Formula
     yield if block_given?
     PythonRequirement.new
   end
-  alias_method :python2, :python
-  alias_method :python3, :python
+  alias python2 python
+  alias python3 python
 
   def startup_plist
     odeprecated "Formula#startup_plist", "Formula#plist"
diff --git a/Library/Homebrew/compat/formula_specialties.rb b/Library/Homebrew/compat/formula_specialties.rb
index f709bcb5b..ec5e91ce8 100644
--- a/Library/Homebrew/compat/formula_specialties.rb
+++ b/Library/Homebrew/compat/formula_specialties.rb
@@ -25,7 +25,7 @@ class AmazonWebServicesFormula < Formula
     libexec.install Dir["*"]
     bin.install_symlink Dir["#{libexec}/bin/*"] - ["#{libexec}/bin/service"]
   end
-  alias_method :standard_install, :install
+  alias standard_install install
 
   # Use this method to generate standard caveats.
   def standard_instructions(home_name, home_value = libexec)
diff --git a/Library/Homebrew/compat/macos.rb b/Library/Homebrew/compat/macos.rb
index 957a0b725..6b0166e40 100644
--- a/Library/Homebrew/compat/macos.rb
+++ b/Library/Homebrew/compat/macos.rb
@@ -136,6 +136,11 @@ module OS
         odeprecated "MacOS.has_apple_developer_tools?", "DevelopmentTools.installed?"
         DevelopmentTools.installed?
       end
+
+      def release
+        odeprecated "MacOS.release", "MacOS.version"
+        version
+      end
     end
   end
 end
diff --git a/Library/Homebrew/compilers.rb b/Library/Homebrew/compilers.rb
index 940566643..6330db283 100644
--- a/Library/Homebrew/compilers.rb
+++ b/Library/Homebrew/compilers.rb
@@ -18,7 +18,7 @@ class CompilerFailure
 
   # Allows Apple compiler `fails_with` statements to keep using `build`
   # even though `build` and `version` are the same internally
-  alias_method :build, :version
+  alias build version
 
   # The cause is no longer used so we need not hold a reference to the string
   def cause(_); end
diff --git a/Library/Homebrew/cxxstdlib.rb b/Library/Homebrew/cxxstdlib.rb
index 1f629a8b2..ad859badd 100644
--- a/Library/Homebrew/cxxstdlib.rb
+++ b/Library/Homebrew/cxxstdlib.rb
@@ -16,7 +16,7 @@ class CxxStdlib
     if type && ![:libstdcxx, :libcxx].include?(type)
       raise ArgumentError, "Invalid C++ stdlib type: #{type}"
     end
-    klass = GNU_GCC_REGEXP === compiler.to_s ? GnuStdlib : AppleStdlib
+    klass = compiler.to_s =~ GNU_GCC_REGEXP ? GnuStdlib : AppleStdlib
     klass.new(type, compiler)
   end
 
diff --git a/Library/Homebrew/debrew.rb b/Library/Homebrew/debrew.rb
index 48d449f4a..1c5047a8c 100644
--- a/Library/Homebrew/debrew.rb
+++ b/Library/Homebrew/debrew.rb
@@ -14,7 +14,7 @@ module Debrew
       super(e) unless Debrew.debug(e) == :ignore
     end
 
-    alias_method :fail, :raise
+    alias fail raise
   end
 
   module Formula
@@ -75,7 +75,7 @@ module Debrew
   end
 
   class << self
-    alias_method :original_raise, :raise
+    alias original_raise raise
   end
 
   @active = false
@@ -118,20 +118,22 @@ module Debrew
           menu.prompt = "Choose an action: "
 
           menu.choice(:raise) { original_raise(e) }
-          menu.choice(:ignore) { return :ignore } if Ignorable === e
+          menu.choice(:ignore) { return :ignore } if e.is_a?(Ignorable)
           menu.choice(:backtrace) { puts e.backtrace }
 
-          menu.choice(:irb) do
-            puts "When you exit this IRB session, execution will continue."
-            set_trace_func proc { |event, _, _, id, binding, klass|
-              if klass == Raise && id == :raise && event == "return"
-                set_trace_func(nil)
-                synchronize { IRB.start_within(binding) }
-              end
-            }
-
-            return :ignore
-          end if Ignorable === e
+          if e.is_a?(Ignorable)
+            menu.choice(:irb) do
+              puts "When you exit this IRB session, execution will continue."
+              set_trace_func proc { |event, _, _, id, binding, klass|
+                if klass == Raise && id == :raise && event == "return"
+                  set_trace_func(nil)
+                  synchronize { IRB.start_within(binding) }
+                end
+              }
+
+              return :ignore
+            end
+          end
 
           menu.choice(:shell) do
             puts "When you exit this shell, you will return to the menu."
diff --git a/Library/Homebrew/dependencies.rb b/Library/Homebrew/dependencies.rb
index b55d35c2e..951db078d 100644
--- a/Library/Homebrew/dependencies.rb
+++ b/Library/Homebrew/dependencies.rb
@@ -22,7 +22,7 @@ class Dependencies
     @deps * arg
   end
 
-  alias_method :to_ary, :to_a
+  alias to_ary to_a
 
   def optional
     select(&:optional?)
@@ -50,7 +50,7 @@ class Dependencies
   def ==(other)
     deps == other.deps
   end
-  alias_method :eql?, :==
+  alias eql? ==
 
   def inspect
     "#<#{self.class.name}: #{to_a.inspect}>"
@@ -69,7 +69,7 @@ class Requirements
   end
 
   def <<(other)
-    if Comparable === other
+    if other.is_a?(Comparable)
       @reqs.grep(other.class) do |req|
         return self if req > other
         @reqs.delete(req)
@@ -79,5 +79,5 @@ class Requirements
     self
   end
 
-  alias_method :to_ary, :to_a
+  alias to_ary to_a
 end
diff --git a/Library/Homebrew/dependency.rb b/Library/Homebrew/dependency.rb
index c280034a8..6b60654e1 100644
--- a/Library/Homebrew/dependency.rb
+++ b/Library/Homebrew/dependency.rb
@@ -22,7 +22,7 @@ class Dependency
   def ==(other)
     instance_of?(other.class) && name == other.name && tags == other.tags
   end
-  alias_method :eql?, :==
+  alias eql? ==
 
   def hash
     name.hash ^ tags.hash
diff --git a/Library/Homebrew/dependency_collector.rb b/Library/Homebrew/dependency_collector.rb
index 08b5fc12b..56463fa29 100644
--- a/Library/Homebrew/dependency_collector.rb
+++ b/Library/Homebrew/dependency_collector.rb
@@ -49,7 +49,7 @@ class DependencyCollector
   end
 
   def cache_key(spec)
-    if Resource === spec && spec.download_strategy == CurlDownloadStrategy
+    if spec.is_a?(Resource) && spec.download_strategy == CurlDownloadStrategy
       File.extname(spec.url)
     else
       spec
@@ -57,7 +57,7 @@ class DependencyCollector
   end
 
   def build(spec)
-    spec, tags = Hash === spec ? spec.first : spec
+    spec, tags = spec.is_a?(Hash) ? spec.first : spec
     parse_spec(spec, Array(tags))
   end
 
@@ -81,7 +81,7 @@ class DependencyCollector
   end
 
   def parse_string_spec(spec, tags)
-    if HOMEBREW_TAP_FORMULA_REGEX === spec
+    if spec =~ HOMEBREW_TAP_FORMULA_REGEX
       TapDependency.new(spec, tags)
     elsif tags.empty?
       Dependency.new(spec, tags)
@@ -128,17 +128,15 @@ class DependencyCollector
   end
 
   def parse_class_spec(spec, tags)
-    if spec < Requirement
-      spec.new(tags)
-    else
+    unless spec < Requirement
       raise TypeError, "#{spec.inspect} is not a Requirement subclass"
     end
+
+    spec.new(tags)
   end
 
   def ant_dep(spec, tags)
-    if MacOS.version >= :mavericks
-      Dependency.new(spec.to_s, tags)
-    end
+    Dependency.new(spec.to_s, tags)
   end
 
   def resource_dep(spec, tags)
@@ -167,11 +165,13 @@ class DependencyCollector
 
   def parse_url_spec(url, tags)
     case File.extname(url)
-    when ".xz"  then Dependency.new("xz", tags)
+    when ".xz"          then Dependency.new("xz", tags)
     when ".lha", ".lzh" then Dependency.new("lha", tags)
-    when ".lz"  then Dependency.new("lzip", tags)
-    when ".rar" then Dependency.new("unrar", tags)
-    when ".7z"  then Dependency.new("p7zip", tags)
+    when ".lz"          then Dependency.new("lzip", tags)
+    when ".rar"         then Dependency.new("unrar", tags)
+    when ".7z"          then Dependency.new("p7zip", tags)
     end
   end
 end
+
+require "extend/os/dependency_collector"
diff --git a/Library/Homebrew/descriptions.rb b/Library/Homebrew/descriptions.rb
index 5e7a5b06c..0ef4316d3 100644
--- a/Library/Homebrew/descriptions.rb
+++ b/Library/Homebrew/descriptions.rb
@@ -12,9 +12,7 @@ class Descriptions
   # If the cache file exists, load it into, and return, a hash; otherwise,
   # return nil.
   def self.load_cache
-    if CACHE_FILE.exist?
-      @cache = Utils::JSON.load(CACHE_FILE.read)
-    end
+    @cache = Utils::JSON.load(CACHE_FILE.read) if CACHE_FILE.exist?
   end
 
   # Write the cache to disk after ensuring the existence of the containing
@@ -138,6 +136,6 @@ class Descriptions
 
   def short_name_counts
     @short_name_counts ||=
-      short_names.values.each_with_object(Hash.new(0)) { |name, counts| counts[name] += 1; counts }
+      short_names.values.each_with_object(Hash.new(0)) { |name, counts| counts[name] += 1 }
   end
 end
diff --git a/Library/Homebrew/dev-cmd/audit.rb b/Library/Homebrew/dev-cmd/audit.rb
index 20e9a8aff..1a6e47dbe 100644
--- a/Library/Homebrew/dev-cmd/audit.rb
+++ b/Library/Homebrew/dev-cmd/audit.rb
@@ -83,11 +83,11 @@ module Homebrew
       end
     end
 
-    unless problem_count.zero?
-      problems = "problem" + plural(problem_count)
-      formulae = "formula" + plural(formula_count, "e")
-      ofail "#{problem_count} #{problems} in #{formula_count} #{formulae}"
-    end
+    return if problem_count.zero?
+
+    problems = "problem" + plural(problem_count)
+    formulae = "formula" + plural(formula_count, "e")
+    ofail "#{problem_count} #{problems} in #{formula_count} #{formulae}"
   end
 end
 
@@ -279,12 +279,13 @@ class FormulaAuditor
         end
       end
     end
+
     if present.include?("head") && present.include?("head block")
       problem "Should not have both `head` and `head do`"
     end
-    if present.include?("bottle modifier") && present.include?("bottle block")
-      problem "Should not have `bottle :unneeded/:disable` and `bottle do`"
-    end
+
+    return unless present.include?("bottle modifier") && present.include?("bottle block")
+    problem "Should not have `bottle :unneeded/:disable` and `bottle do`"
   end
 
   def audit_class
@@ -348,9 +349,8 @@ class FormulaAuditor
 
     same_name_tap_formulae.delete(full_name)
 
-    unless same_name_tap_formulae.empty?
-      problem "Formula name conflicts with #{same_name_tap_formulae.join ", "}"
-    end
+    return if same_name_tap_formulae.empty?
+    problem "Formula name conflicts with #{same_name_tap_formulae.join ", "}"
   end
 
   def audit_deps
@@ -467,7 +467,7 @@ class FormulaAuditor
 
     # Make sure the formula name plus description is no longer than 80 characters
     # Note full_name includes the name of the tap, while name does not
-    linelength = formula.name.length + ": ".length + desc.length
+    linelength = "#{formula.name}: #{desc}".length
     if linelength > 80
       problem <<-EOS.undent
         Description is too long. \"name: desc\" should be less than 80 characters.
@@ -483,9 +483,8 @@ class FormulaAuditor
       problem "Description shouldn't start with an indefinite article (#{$1})"
     end
 
-    if desc.downcase.start_with? "#{formula.name} "
-      problem "Description shouldn't include the formula name"
-    end
+    return unless desc.downcase.start_with? "#{formula.name} "
+    problem "Description shouldn't include the formula name"
   end
 
   def audit_homepage
@@ -562,9 +561,9 @@ class FormulaAuditor
   end
 
   def audit_bottle_spec
-    if formula.bottle_disabled? && !formula.bottle_disable_reason.valid?
-      problem "Unrecognized bottle modifier"
-    end
+    return unless formula.bottle_disabled?
+    return if formula.bottle_disable_reason.valid?
+    problem "Unrecognized bottle modifier"
   end
 
   def audit_github_repository
@@ -592,9 +591,8 @@ class FormulaAuditor
       problem "GitHub repository not notable enough (<20 forks, <20 watchers and <50 stars)"
     end
 
-    if Date.parse(metadata["created_at"]) > (Date.today - 30)
-      problem "GitHub repository too new (<30 days old)"
-    end
+    return if Date.parse(metadata["created_at"]) <= (Date.today - 30)
+    problem "GitHub repository too new (<30 days old)"
   end
 
   def audit_specs
@@ -668,24 +666,26 @@ class FormulaAuditor
     end
 
     revision_map = attributes_map[:revision]
-    if formula.revision.nonzero?
-      if formula.stable
-        if revision_map[formula.stable.version].empty? # check stable spec
-          problem "'revision #{formula.revision}' should be removed"
-        end
-      else # head/devel-only formula
+
+    return if formula.revision.zero?
+
+    if formula.stable
+      if revision_map[formula.stable.version].empty? # check stable spec
         problem "'revision #{formula.revision}' should be removed"
       end
+    else # head/devel-only formula
+      problem "'revision #{formula.revision}' should be removed"
     end
   end
 
   def audit_legacy_patches
     return unless formula.respond_to?(:patches)
     legacy_patches = Patch.normalize_legacy_patches(formula.patches).grep(LegacyPatch)
-    unless legacy_patches.empty?
-      problem "Use the patch DSL instead of defining a 'patches' method"
-      legacy_patches.each { |p| audit_patch(p) }
-    end
+
+    return if legacy_patches.empty?
+
+    problem "Use the patch DSL instead of defining a 'patches' method"
+    legacy_patches.each { |p| audit_patch(p) }
   end
 
   def audit_patch(patch)
@@ -732,9 +732,8 @@ class FormulaAuditor
       problem "Please set plist_options when using a formula-defined plist."
     end
 
-    if text.include?('require "language/go"') && !text.include?("go_resource")
-      problem "require \"language/go\" is unnecessary unless using `go_resource`s"
-    end
+    return unless text.include?('require "language/go"') && !text.include?("go_resource")
+    problem "require \"language/go\" is unnecessary unless using `go_resource`s"
   end
 
   def audit_line(line, lineno)
@@ -961,61 +960,55 @@ class FormulaAuditor
       problem "Use Language::Node for npm install args"
     end
 
-    if @strict
-      if line =~ /system ((["'])[^"' ]*(?:\s[^"' ]*)+\2)/
-        bad_system = $1
-        unless %w[| < > & ; *].any? { |c| bad_system.include? c }
-          good_system = bad_system.gsub(" ", "\", \"")
-          problem "Use `system #{good_system}` instead of `system #{bad_system}` "
-        end
-      end
+    return unless @strict
 
-      if line =~ /(require ["']formula["'])/
-        problem "`#{$1}` is now unnecessary"
+    if line =~ /system ((["'])[^"' ]*(?:\s[^"' ]*)+\2)/
+      bad_system = $1
+      unless %w[| < > & ; *].any? { |c| bad_system.include? c }
+        good_system = bad_system.gsub(" ", "\", \"")
+        problem "Use `system #{good_system}` instead of `system #{bad_system}` "
       end
+    end
 
-      if line =~ %r{#\{share\}/#{Regexp.escape(formula.name)}[/'"]}
-        problem "Use \#{pkgshare} instead of \#{share}/#{formula.name}"
-      end
+    if line =~ /(require ["']formula["'])/
+      problem "`#{$1}` is now unnecessary"
+    end
 
-      if line =~ %r{share(\s*[/+]\s*)(['"])#{Regexp.escape(formula.name)}(?:\2|/)}
-        problem "Use pkgshare instead of (share#{$1}\"#{formula.name}\")"
-      end
+    if line =~ %r{#\{share\}/#{Regexp.escape(formula.name)}[/'"]}
+      problem "Use \#{pkgshare} instead of \#{share}/#{formula.name}"
     end
+
+    return unless line =~ %r{share(\s*[/+]\s*)(['"])#{Regexp.escape(formula.name)}(?:\2|/)}
+    problem "Use pkgshare instead of (share#{$1}\"#{formula.name}\")"
   end
 
   def audit_caveats
-    caveats = formula.caveats.to_s
-
-    if caveats.include?("setuid")
-      problem "Don't recommend setuid in the caveats, suggest sudo instead."
-    end
+    return unless formula.caveats.to_s.include?("setuid")
+    problem "Don't recommend setuid in the caveats, suggest sudo instead."
   end
 
   def audit_reverse_migration
     # Only enforce for new formula being re-added to core and official taps
     return unless @strict
     return unless formula.tap && formula.tap.official?
+    return unless formula.tap.tap_migrations.key?(formula.name)
 
-    if formula.tap.tap_migrations.key?(formula.name)
-      problem <<-EOS.undent
-        #{formula.name} seems to be listed in tap_migrations.json!
-        Please remove #{formula.name} from present tap & tap_migrations.json
-        before submitting it to Homebrew/homebrew-#{formula.tap.repo}.
-      EOS
-    end
+    problem <<-EOS.undent
+      #{formula.name} seems to be listed in tap_migrations.json!
+      Please remove #{formula.name} from present tap & tap_migrations.json
+      before submitting it to Homebrew/homebrew-#{formula.tap.repo}.
+    EOS
   end
 
   def audit_prefix_has_contents
     return unless formula.prefix.directory?
+    return unless Keg.new(formula.prefix).empty_installation?
 
-    if Keg.new(formula.prefix).empty_installation?
-      problem <<-EOS.undent
-        The installation seems to be empty. Please ensure the prefix
-        is set correctly and expected files are installed.
-        The prefix configure/make argument may be case-sensitive.
-      EOS
-    end
+    problem <<-EOS.undent
+      The installation seems to be empty. Please ensure the prefix
+      is set correctly and expected files are installed.
+      The prefix configure/make argument may be case-sensitive.
+    EOS
   end
 
   def audit_conditional_dep(dep, condition, line)
@@ -1116,9 +1109,8 @@ class ResourceAuditor
       problem "version #{version} should not have a leading 'v'"
     end
 
-    if version.to_s =~ /_\d+$/
-      problem "version #{version} should not end with an underline and a number"
-    end
+    return unless version.to_s =~ /_\d+$/
+    problem "version #{version} should not end with an underline and a number"
   end
 
   def audit_checksum
@@ -1184,11 +1176,8 @@ class ResourceAuditor
       end
     end
 
-    using_strategy = DownloadStrategyDetector.detect("", using)
-
-    if url_strategy == using_strategy
-      problem "Redundant :using value in URL"
-    end
+    return unless url_strategy == DownloadStrategyDetector.detect("", using)
+    problem "Redundant :using value in URL"
   end
 
   def audit_urls
diff --git a/Library/Homebrew/dev-cmd/bottle.rb b/Library/Homebrew/dev-cmd/bottle.rb
index 9676e374c..b2aa3b2c5 100644
--- a/Library/Homebrew/dev-cmd/bottle.rb
+++ b/Library/Homebrew/dev-cmd/bottle.rb
@@ -51,10 +51,11 @@ module Homebrew
       end
 
       @put_filenames ||= []
-      unless @put_filenames.include? filename
-        puts "#{Tty.red}#{filename}#{Tty.reset}"
-        @put_filenames << filename
-      end
+
+      return if @put_filenames.include? filename
+
+      puts "#{Tty.red}#{filename}#{Tty.reset}"
+      @put_filenames << filename
     end
 
     result = false
@@ -107,9 +108,7 @@ module Homebrew
     absolute_symlinks_start_with_string = []
     keg.find do |pn|
       next unless pn.symlink? && (link = pn.readlink).absolute?
-      if link.to_s.start_with?(string)
-        absolute_symlinks_start_with_string << pn
-      end
+      absolute_symlinks_start_with_string << pn if link.to_s.start_with?(string)
     end
 
     if ARGV.verbose?
@@ -137,11 +136,11 @@ module Homebrew
     tap = f.tap
 
     unless tap
-      if ARGV.include?("--force-core-tap")
-        tap = CoreTap.instance
-      else
+      unless ARGV.include?("--force-core-tap")
         return ofail "Formula not from core or any taps: #{f.full_name}"
       end
+
+      tap = CoreTap.instance
     end
 
     if f.bottle_disabled?
@@ -154,9 +153,7 @@ module Homebrew
       return ofail "Formula not installed with '--build-bottle': #{f.full_name}"
     end
 
-    unless f.stable
-      return ofail "Formula has no stable version: #{f.full_name}"
-    end
+    return ofail "Formula has no stable version: #{f.full_name}" unless f.stable
 
     if ARGV.include?("--no-rebuild") || !f.tap
       rebuild = 0
@@ -255,7 +252,7 @@ module Homebrew
           if prefix != prefix_check
             relocatable = false if keg_contain_absolute_symlink_starting_with?(prefix, keg)
           end
-          skip_relocation = relocatable && !keg.require_install_name_tool?
+          skip_relocation = relocatable && !keg.require_relocation?
         end
         puts if !relocatable && ARGV.verbose?
       rescue Interrupt
@@ -323,34 +320,33 @@ module Homebrew
     puts "./#{filename}"
     puts output
 
-    if ARGV.include? "--json"
-      json = {
-        f.full_name => {
-          "formula" => {
-            "pkg_version" => f.pkg_version.to_s,
-            "path" => f.path.to_s.strip_prefix("#{HOMEBREW_REPOSITORY}/"),
-          },
-          "bottle" => {
-            "root_url" => bottle.root_url,
-            "prefix" => bottle.prefix,
-            "cellar" => bottle.cellar.to_s,
-            "rebuild" => bottle.rebuild,
-            "tags" => {
-              Utils::Bottles.tag.to_s => {
-                "filename" => filename.to_s,
-                "sha256" => sha256,
-              },
+    return unless ARGV.include? "--json"
+    json = {
+      f.full_name => {
+        "formula" => {
+          "pkg_version" => f.pkg_version.to_s,
+          "path" => f.path.to_s.strip_prefix("#{HOMEBREW_REPOSITORY}/"),
+        },
+        "bottle" => {
+          "root_url" => bottle.root_url,
+          "prefix" => bottle.prefix,
+          "cellar" => bottle.cellar.to_s,
+          "rebuild" => bottle.rebuild,
+          "tags" => {
+            Utils::Bottles.tag.to_s => {
+              "filename" => filename.to_s,
+              "sha256" => sha256,
             },
           },
-          "bintray" => {
-            "package" => Utils::Bottles::Bintray.package(f.name),
-            "repository" => Utils::Bottles::Bintray.repository(tap),
-          },
         },
-      }
-      File.open("#{filename.prefix}.bottle.json", "w") do |file|
-        file.write Utils::JSON.dump json
-      end
+        "bintray" => {
+          "package" => Utils::Bottles::Bintray.package(f.name),
+          "repository" => Utils::Bottles::Bintray.repository(tap),
+        },
+      },
+    }
+    File.open("#{filename.prefix}.bottle.json", "w") do |file|
+      file.write Utils::JSON.dump json
     end
   end
 
@@ -436,7 +432,7 @@ module Homebrew
             puts output
             update_or_add = "add"
             if s.include? "stable do"
-              indent = s.slice(/^ +stable do/).length - "stable do".length
+              indent = s.slice(/^( +)stable do/, 1).length
               string = s.sub!(/^ {#{indent}}stable do(.|\n)+?^ {#{indent}}end\n/m, '\0' + output + "\n")
             else
               string = s.sub!(
diff --git a/Library/Homebrew/dev-cmd/bump-formula-pr.rb b/Library/Homebrew/dev-cmd/bump-formula-pr.rb
index 38c7559fb..ce10da52a 100644
--- a/Library/Homebrew/dev-cmd/bump-formula-pr.rb
+++ b/Library/Homebrew/dev-cmd/bump-formula-pr.rb
@@ -27,7 +27,7 @@ require "formula"
 module Homebrew
   def inreplace_pairs(path, replacement_pairs)
     if ARGV.dry_run?
-      contents = path.open("r") { |f| Formulary.set_encoding(f).read }
+      contents = path.open("r") { |f| Formulary.ensure_utf8_encoding(f).read }
       contents.extend(StringInreplaceExtension)
       replacement_pairs.each do |old, new|
         unless ARGV.flag?("--quiet")
@@ -48,7 +48,7 @@ module Homebrew
           s.gsub!(old, new)
         end
       end
-      path.open("r") { |f| Formulary.set_encoding(f).read }
+      path.open("r") { |f| Formulary.ensure_utf8_encoding(f).read }
     end
   end
 
diff --git a/Library/Homebrew/dev-cmd/edit.rb b/Library/Homebrew/dev-cmd/edit.rb
index f80d05861..2d2a5ec08 100644
--- a/Library/Homebrew/dev-cmd/edit.rb
+++ b/Library/Homebrew/dev-cmd/edit.rb
@@ -33,9 +33,9 @@ module Homebrew
       # Don't use ARGV.formulae as that will throw if the file doesn't parse
       paths = ARGV.named.map do |name|
         path = Formulary.path(name)
-        unless path.file? || ARGV.force?
-          raise FormulaUnavailableError, name
-        end
+
+        raise FormulaUnavailableError, name unless path.file? || ARGV.force?
+
         path
       end
       exec_editor(*paths)
diff --git a/Library/Homebrew/dev-cmd/man.rb b/Library/Homebrew/dev-cmd/man.rb
index 0627241a3..871fbf46c 100644
--- a/Library/Homebrew/dev-cmd/man.rb
+++ b/Library/Homebrew/dev-cmd/man.rb
@@ -52,17 +52,12 @@ module Homebrew
     variables[:commands] = path_glob_commands("#{HOMEBREW_LIBRARY_PATH}/cmd/*.{rb,sh}")
     variables[:developer_commands] = path_glob_commands("#{HOMEBREW_LIBRARY_PATH}/dev-cmd/*.{rb,sh}")
     readme = HOMEBREW_REPOSITORY/"README.md"
-    variables[:lead_maintainer] = readme
-                                  .read[/Homebrew's lead maintainer is (.*)\./, 1]
-                                  .scan(/\[([^\]]*)\]/).flatten.first
-    variables[:maintainers] = readme
-                              .read[/Homebrew's current maintainers are (.*)\./, 1]
-                              .scan(/\[([^\]]*)\]/).flatten
-    former_maintainers = readme
-                         .read[/Former maintainers with significant contributions include (.*)\./, 1]
-                         .scan(/\[([^\]]*)\]/).flatten
-    variables[:former_maintainers] = former_maintainers[0...-1]
-    variables[:creator] = former_maintainers.last
+    variables[:lead_maintainer] = readme.read[/(Homebrew's lead maintainer .*\.)/, 1]
+                                        .gsub(/\[([^\]]+)\]\([^)]+\)/, '\1')
+    variables[:maintainers] = readme.read[/(Homebrew's current maintainers .*\.)/, 1]
+                                    .gsub(/\[([^\]]+)\]\([^)]+\)/, '\1')
+    variables[:former_maintainers] = readme.read[/(Former maintainers .*\.)/, 1]
+                                           .gsub(/\[([^\]]+)\]\([^)]+\)/, '\1')
 
     ERB.new(template, nil, ">").result(variables.instance_eval { binding })
   end
diff --git a/Library/Homebrew/dev-cmd/mirror.rb b/Library/Homebrew/dev-cmd/mirror.rb
index 162008123..9966163f8 100644
--- a/Library/Homebrew/dev-cmd/mirror.rb
+++ b/Library/Homebrew/dev-cmd/mirror.rb
@@ -4,9 +4,7 @@
 
 module Homebrew
   def mirror
-    if ARGV.named.empty?
-      odie "This command requires at least formula argument!"
-    end
+    odie "This command requires at least formula argument!" if ARGV.named.empty?
 
     bintray_user = ENV["BINTRAY_USER"]
     bintray_key = ENV["BINTRAY_KEY"]
diff --git a/Library/Homebrew/dev-cmd/pull.rb b/Library/Homebrew/dev-cmd/pull.rb
index 7f027e159..857c55993 100644
--- a/Library/Homebrew/dev-cmd/pull.rb
+++ b/Library/Homebrew/dev-cmd/pull.rb
@@ -41,12 +41,12 @@ require "pkg_version"
 
 module Homebrew
   def pull
-    if ARGV[0] == "--rebase"
-      odie "You meant `git pull --rebase`."
-    end
+    odie "You meant `git pull --rebase`." if ARGV[0] == "--rebase"
+
     if ARGV.named.empty?
       odie "This command requires at least one argument containing a URL or pull request number"
     end
+
     do_bump = ARGV.include?("--bump") && !ARGV.include?("--clean")
 
     # Formulae with affected bottles that were published
@@ -429,9 +429,9 @@ module Homebrew
     # Returns nil if formula is absent or if there was an error reading it
     def self.lookup(name)
       json = Utils.popen_read(HOMEBREW_BREW_FILE, "info", "--json=v1", name)
-      unless $?.success?
-        return nil
-      end
+
+      return nil unless $?.success?
+
       Homebrew.force_utf8!(json)
       FormulaInfoFromJson.new(Utils::JSON.load(json)[0])
     end
@@ -531,19 +531,19 @@ module Homebrew
             req = Net::HTTP::Head.new bottle_info.url
             req.initialize_http_header "User-Agent" => HOMEBREW_USER_AGENT_RUBY
             res = http.request req
-            if res.is_a?(Net::HTTPSuccess)
-              break
-            elsif res.is_a?(Net::HTTPClientError)
-              if retry_count >= max_retries
-                raise "Failed to find published #{f} bottle at #{url}!"
-              end
-              print(wrote_dots ? "." : "Waiting on Bintray.")
-              wrote_dots = true
-              sleep poll_retry_delay_seconds
-              retry_count += 1
-            else
+            break if res.is_a?(Net::HTTPSuccess)
+
+            unless res.is_a?(Net::HTTPClientError)
               raise "Failed to find published #{f} bottle at #{url} (#{res.code} #{res.message})!"
             end
+
+            if retry_count >= max_retries
+              raise "Failed to find published #{f} bottle at #{url}!"
+            end
+            print(wrote_dots ? "." : "Waiting on Bintray.")
+            wrote_dots = true
+            sleep poll_retry_delay_seconds
+            retry_count += 1
           end
         end
 
diff --git a/Library/Homebrew/dev-cmd/test-bot.rb b/Library/Homebrew/dev-cmd/test-bot.rb
deleted file mode 100644
index d20711588..000000000
--- a/Library/Homebrew/dev-cmd/test-bot.rb
+++ /dev/null
@@ -1,1172 +0,0 @@
-#: @hide_from_man_page
-#:  * `test-bot` [options]  <url|formula>:
-#:    Tests the full lifecycle of a formula or Homebrew/brew change.
-#:
-#:    If `--dry-run` is passed, print what would be done rather than doing
-#:    it.
-#:
-#:    If `--local` is passed, perform only local operations (i.e. don't
-#:    push or create PR).
-#:
-#:    If `--keep-logs` is passed, write and keep log files under
-#:    `./brewbot/`.
-#:
-#:    If `--cleanup` is passed, clean all state from the Homebrew
-#:    directory. Use with care!
-#:
-#:    If `--clean-cache` is passed, remove all cached downloads. Use with
-#:    care!
-#:
-#:    If `--skip-setup` is passed, don't check the local system is setup
-#:    correctly.
-#:
-#:    If `--skip-homebrew` is passed, don't check Homebrew's files and
-#:    tests are all valid.
-#:
-#:    If `--junit` is passed, generate a JUnit XML test results file.
-#:
-#:    If `--no-bottle` is passed, run `brew install` without
-#:    `--build-bottle`.
-#:
-#:    If `--keep-old` is passed, run `brew bottle --keep-old` to build new
-#:    bottles for a single platform.
-#:
-#:    If `--skip-relocation` is passed, run
-#:   `brew bottle --skip-relocation` to build new bottles that don't
-#:    require relocation.
-#:
-#:    If `--HEAD` is passed, run `brew install` with `--HEAD`.
-#:
-#:    If `--local` is passed, ask Homebrew to write verbose logs under
-#:    `./logs/` and set `$HOME` to `./home/`.
-#:
-#:    If `--tap=<tap>` is passed, use the `git` repository of the given
-#:    tap.
-#:
-#:    If `--dry-run` is passed, just print commands, don't run them.
-#:
-#:    If `--fail-fast` is passed, immediately exit on a failing step.
-#:
-#:    If `--verbose` is passed, print test step output in real time. Has
-#:    the side effect of passing output as raw bytes instead of
-#:    re-encoding in UTF-8.
-#:
-#:    If `--fast` is passed, don't install any packages, but run e.g.
-#:    `brew audit` anyway.
-#:
-#:    If `--keep-tmp` is passed, keep temporary files written by main
-#:    installs and tests that are run.
-#:
-#:    If `--no-pull` is passed, don't use `brew pull` when possible.
-#:
-#:    If `--coverage` is passed, generate and uplaod a coverage report.
-#:
-#:    If `--test-default-formula` is passed, use a default testing formula
-#:    when not building a tap and no other formulae are specified.
-#:
-#:    If `--ci-master` is passed, use the Homebrew master branch CI
-#:    options.
-#:
-#:    If `--ci-pr` is passed, use the Homebrew pull request CI options.
-#:
-#:    If `--ci-testing` is passed, use the Homebrew testing CI options.
-#:
-#:    If `--ci-auto` is passed, automatically pick one of the Homebrew CI
-#:    options based on the environment.
-#:
-#:    If `--ci-upload` is passed, use the Homebrew CI bottle upload
-#:    options.
-#:
-#
-#:    Influential environment variables include:
-#:    `TRAVIS_REPO_SLUG`: same as `--tap`
-#:    `GIT_URL`: if set to URL of a tap remote, same as `--tap`
-
-require "formula"
-require "utils"
-require "date"
-require "rexml/document"
-require "rexml/xmldecl"
-require "rexml/cdata"
-require "tap"
-require "development_tools"
-require "utils/bottles"
-
-module Homebrew
-  BYTES_IN_1_MEGABYTE = 1024*1024
-  MAX_STEP_OUTPUT_SIZE = BYTES_IN_1_MEGABYTE - (200*1024) # margin of safety
-
-  HOMEBREW_TAP_REGEX = %r{^([\w-]+)/homebrew-([\w-]+)$}
-
-  def fix_encoding!(str)
-    # Assume we are starting from a "mostly" UTF-8 string
-    str.force_encoding(Encoding::UTF_8)
-    return str if str.valid_encoding?
-    str.encode!(Encoding::UTF_16, invalid: :replace)
-    str.encode!(Encoding::UTF_8)
-  end
-
-  def resolve_test_tap
-    if tap = ARGV.value("tap")
-      return Tap.fetch(tap)
-    end
-
-    if (tap = ENV["TRAVIS_REPO_SLUG"]) && (tap =~ HOMEBREW_TAP_REGEX)
-      return Tap.fetch(tap)
-    end
-
-    if ENV["UPSTREAM_BOT_PARAMS"]
-      bot_argv = ENV["UPSTREAM_BOT_PARAMS"].split " "
-      bot_argv.extend HomebrewArgvExtension
-      if tap = bot_argv.value("tap")
-        return Tap.fetch(tap)
-      end
-    end
-
-    if git_url = ENV["UPSTREAM_GIT_URL"] || ENV["GIT_URL"]
-      # Also can get tap from Jenkins GIT_URL.
-      url_path = git_url.sub(%r{^https?://github\.com/}, "").chomp("/").sub(/\.git$/, "")
-      begin
-        return Tap.fetch(url_path) if url_path =~ HOMEBREW_TAP_REGEX
-      rescue
-      end
-    end
-  end
-
-  # Wraps command invocations. Instantiated by Test#test.
-  # Handles logging and pretty-printing.
-  class Step
-    attr_reader :command, :name, :status, :output
-
-    # Instantiates a Step object.
-    # @param test [Test] The parent Test object
-    # @param command [Array<String>] Command to execute and arguments
-    # @param options [Hash] Recognized options are:
-    #   :puts_output_on_success
-    #   :repository
-    def initialize(test, command, options = {})
-      @test = test
-      @category = test.category
-      @command = command
-      @puts_output_on_success = options[:puts_output_on_success]
-      @name = command[1].delete("-")
-      @status = :running
-      @repository = options[:repository] || HOMEBREW_REPOSITORY
-    end
-
-    def log_file_path
-      file = "#{@category}.#{@name}.txt"
-      root = @test.log_root
-      root ? root + file : file
-    end
-
-    def command_short
-      (@command - %w[brew --force --retry --verbose --build-bottle --json]).join(" ")
-    end
-
-    def passed?
-      @status == :passed
-    end
-
-    def failed?
-      @status == :failed
-    end
-
-    def puts_command
-      if ENV["TRAVIS"]
-        @@travis_step_num ||= 0
-        @travis_fold_id = @command.first(2).join(".") + ".#{@@travis_step_num += 1}"
-        @travis_timer_id = rand(2**32).to_s(16)
-        puts "travis_fold:start:#{@travis_fold_id}"
-        puts "travis_time:start:#{@travis_timer_id}"
-      end
-      puts "#{Tty.blue}==>#{Tty.white} #{@command.join(" ")}#{Tty.reset}"
-    end
-
-    def puts_result
-      if ENV["TRAVIS"]
-        travis_start_time = @start_time.to_i*1000000000
-        travis_end_time = @end_time.to_i*1000000000
-        travis_duration = travis_end_time - travis_start_time
-        puts "#{Tty.white}==>#{Tty.green} PASSED#{Tty.reset}" if passed?
-        puts "travis_time:end:#{@travis_timer_id},start=#{travis_start_time},finish=#{travis_end_time},duration=#{travis_duration}"
-        puts "travis_fold:end:#{@travis_fold_id}"
-      end
-      puts "#{Tty.white}==>#{Tty.red} FAILED#{Tty.reset}" if failed?
-    end
-
-    def output?
-      @output && !@output.empty?
-    end
-
-    # The execution time of the task.
-    # Precondition: Step#run has been called.
-    # @return [Float] execution time in seconds
-    def time
-      @end_time - @start_time
-    end
-
-    def run
-      @start_time = Time.now
-
-      puts_command
-      if ARGV.include? "--dry-run"
-        @end_time = Time.now
-        @status = :passed
-        puts_result
-        return
-      end
-
-      verbose = ARGV.verbose?
-      # Step may produce arbitrary output and we read it bytewise, so must
-      # buffer it as binary and convert to UTF-8 once complete
-      output = "".encode!("BINARY")
-      working_dir = Pathname.new(@command.first == "git" ? @repository : Dir.pwd)
-      read, write = IO.pipe
-
-      begin
-        pid = fork do
-          read.close
-          $stdout.reopen(write)
-          $stderr.reopen(write)
-          write.close
-          working_dir.cd { exec(*@command) }
-        end
-        write.close
-        while buf = read.readpartial(4096)
-          if verbose
-            print buf
-            $stdout.flush
-          end
-          output << buf
-        end
-      rescue EOFError
-      ensure
-        read.close
-      end
-
-      Process.wait(pid)
-      @end_time = Time.now
-      @status = $?.success? ? :passed : :failed
-      puts_result
-
-      unless output.empty?
-        @output = Homebrew.fix_encoding!(output)
-        puts @output if (failed? || @puts_output_on_success) && !verbose
-        File.write(log_file_path, @output) if ARGV.include? "--keep-logs"
-      end
-
-      exit 1 if ARGV.include?("--fail-fast") && failed?
-    end
-  end
-
-  class Test
-    attr_reader :log_root, :category, :name, :steps
-
-    def initialize(argument, options = {})
-      @hash = nil
-      @url = nil
-      @formulae = []
-      @added_formulae = []
-      @modified_formula = []
-      @steps = []
-      @tap = options[:tap]
-      @repository = @tap ? @tap.path : HOMEBREW_REPOSITORY
-      @skip_homebrew = options.fetch(:skip_homebrew, false)
-
-      if quiet_system "git", "-C", @repository.to_s, "rev-parse", "--verify", "-q", argument
-        @hash = argument
-      elsif url_match = argument.match(HOMEBREW_PULL_OR_COMMIT_URL_REGEX)
-        @url = url_match[0]
-      elsif canonical_formula_name = safe_formula_canonical_name(argument)
-        @formulae = [canonical_formula_name]
-      else
-        raise ArgumentError, "#{argument} is not a pull request URL, commit URL or formula name."
-      end
-
-      @category = __method__
-      @brewbot_root = Pathname.pwd + "brewbot"
-      FileUtils.mkdir_p @brewbot_root
-    end
-
-    def no_args?
-      @hash == "HEAD"
-    end
-
-    def safe_formula_canonical_name(formula_name)
-      Formulary.factory(formula_name).full_name
-    rescue TapFormulaUnavailableError => e
-      raise if e.tap.installed?
-      test "brew", "tap", e.tap.name
-      retry unless steps.last.failed?
-      onoe e
-      puts e.backtrace if ARGV.debug?
-    rescue FormulaUnavailableError, TapFormulaAmbiguityError, TapFormulaWithOldnameAmbiguityError => e
-      onoe e
-      puts e.backtrace if ARGV.debug?
-    end
-
-    def git(*args)
-      @repository.cd { Utils.popen_read("git", *args) }
-    end
-
-    def download
-      def shorten_revision(revision)
-        git("rev-parse", "--short", revision).strip
-      end
-
-      def current_sha1
-        shorten_revision "HEAD"
-      end
-
-      def current_branch
-        git("symbolic-ref", "HEAD").gsub("refs/heads/", "").strip
-      end
-
-      def single_commit?(start_revision, end_revision)
-        git("rev-list", "--count", "#{start_revision}..#{end_revision}").to_i == 1
-      end
-
-      def diff_formulae(start_revision, end_revision, path, filter)
-        return unless @tap
-        git(
-          "diff-tree", "-r", "--name-only", "--diff-filter=#{filter}",
-          start_revision, end_revision, "--", path
-        ).lines.map do |line|
-          file = Pathname.new line.chomp
-          next unless @tap.formula_file?(file)
-          @tap.formula_file_to_name(file)
-        end.compact
-      end
-
-      @category = __method__
-      @start_branch = current_branch
-
-      travis_pr = ENV["TRAVIS_PULL_REQUEST"] && ENV["TRAVIS_PULL_REQUEST"] != "false"
-
-      # Use Jenkins GitHub Pull Request Builder plugin variables for
-      # pull request jobs.
-      if ENV["ghprbPullLink"]
-        @url = ENV["ghprbPullLink"]
-        @hash = nil
-        test "git", "checkout", "origin/master"
-      elsif ENV["GIT_URL"] && ENV["GIT_BRANCH"]
-        git_url = ENV["GIT_URL"].chomp("/").chomp(".git")
-        %r{origin/pr/(\d+)/(merge|head)} =~ ENV["GIT_BRANCH"]
-        pr = $1
-        @url = "#{git_url}/pull/#{pr}"
-        @hash = nil
-      # Use Travis CI pull-request variables for pull request jobs.
-      elsif travis_pr
-        @url = "https://github.com/#{ENV["TRAVIS_REPO_SLUG"]}/pull/#{ENV["TRAVIS_PULL_REQUEST"]}"
-        @hash = nil
-      end
-
-      # Use Jenkins Git plugin variables for master branch jobs.
-      if ENV["GIT_PREVIOUS_COMMIT"] && ENV["GIT_COMMIT"]
-        diff_start_sha1 = ENV["GIT_PREVIOUS_COMMIT"]
-        diff_end_sha1 = ENV["GIT_COMMIT"]
-      # Use Travis CI Git variables for master or branch jobs.
-      elsif ENV["TRAVIS_COMMIT_RANGE"]
-        diff_start_sha1, diff_end_sha1 = ENV["TRAVIS_COMMIT_RANGE"].split "..."
-      # Otherwise just use the current SHA-1 (which may be overriden later)
-      else
-        diff_end_sha1 = diff_start_sha1 = current_sha1
-      end
-
-      diff_start_sha1 = git("merge-base", diff_start_sha1, diff_end_sha1).strip
-
-      # Handle no arguments being passed on the command-line e.g. `brew test-bot`.
-      if no_args?
-        if diff_start_sha1 == diff_end_sha1 || \
-           single_commit?(diff_start_sha1, diff_end_sha1)
-          @name = diff_end_sha1
-        else
-          @name = "#{diff_start_sha1}-#{diff_end_sha1}"
-        end
-      # Handle formulae arguments being passed on the command-line e.g. `brew test-bot wget fish`.
-      elsif !@formulae.empty?
-        @name = "#{@formulae.first}-#{diff_end_sha1}"
-        diff_start_sha1 = diff_end_sha1
-      # Handle a hash being passed on the command-line e.g. `brew test-bot 1a2b3c`.
-      elsif @hash
-        test "git", "checkout", @hash
-        diff_start_sha1 = "#{@hash}^"
-        diff_end_sha1 = @hash
-        @name = @hash
-      # Handle a URL being passed on the command-line or through Jenkins/Travis
-      # environment variables e.g.
-      # `brew test-bot https://github.com/Homebrew/homebrew-core/pull/678`.
-      elsif @url
-        # TODO: in future Travis CI may need to also use `brew pull` to e.g. push
-        # the right commit to BrewTestBot.
-        if !travis_pr && !ARGV.include?("--no-pull")
-          diff_start_sha1 = current_sha1
-          test "brew", "pull", "--clean", @url
-          diff_end_sha1 = current_sha1
-        end
-        @short_url = @url.gsub("https://github.com/", "")
-        if @short_url.include? "/commit/"
-          # 7 characters should be enough for a commit (not 40).
-          @short_url.gsub!(%r{(commit/\w{7}).*/}, '\1')
-          @name = @short_url
-        else
-          @name = "#{@short_url}-#{diff_end_sha1}"
-        end
-      else
-        raise "Cannot set @name: invalid command-line arguments!"
-      end
-
-      @log_root = @brewbot_root + @name
-      FileUtils.mkdir_p @log_root
-
-      return unless diff_start_sha1 != diff_end_sha1
-      return if @url && steps.last && !steps.last.passed?
-
-      if @tap
-        formula_path = @tap.formula_dir.to_s
-        @added_formulae += diff_formulae(diff_start_sha1, diff_end_sha1, formula_path, "A")
-        @modified_formula += diff_formulae(diff_start_sha1, diff_end_sha1, formula_path, "M")\
-      elsif @formulae.empty? && ARGV.include?("--test-default-formula")
-        # Build the default test formula.
-        HOMEBREW_CACHE_FORMULA.mkpath
-        testbottest = "#{HOMEBREW_LIBRARY}/Homebrew/test/testbottest.rb"
-        FileUtils.cp testbottest, HOMEBREW_CACHE_FORMULA
-        @test_default_formula = true
-        @added_formulae = [testbottest]
-      end
-
-      @formulae += @added_formulae + @modified_formula
-    end
-
-    def skip(formula_name)
-      puts "#{Tty.blue}==>#{Tty.white} SKIPPING: #{formula_name}#{Tty.reset}"
-    end
-
-    def satisfied_requirements?(formula, spec, dependency = nil)
-      requirements = formula.send(spec).requirements
-
-      unsatisfied_requirements = requirements.reject do |requirement|
-        satisfied = false
-        satisfied ||= requirement.satisfied?
-        satisfied ||= requirement.optional?
-        if !satisfied && requirement.default_formula?
-          default = Formula[requirement.default_formula]
-          satisfied = satisfied_requirements?(default, :stable, formula.full_name)
-        end
-        satisfied
-      end
-
-      if unsatisfied_requirements.empty?
-        true
-      else
-        name = formula.full_name
-        name += " (#{spec})" unless spec == :stable
-        name += " (#{dependency} dependency)" if dependency
-        skip name
-        puts unsatisfied_requirements.map(&:message)
-        false
-      end
-    end
-
-    def setup
-      @category = __method__
-      return if ARGV.include? "--skip-setup"
-      if !ENV["TRAVIS"] && HOMEBREW_PREFIX.to_s == "/usr/local"
-        test "brew", "doctor"
-      end
-      test "brew", "--env"
-      test "brew", "config"
-    end
-
-    def formula(formula_name)
-      @category = "#{__method__}.#{formula_name}"
-
-      test "brew", "uses", formula_name
-
-      formula = Formulary.factory(formula_name)
-
-      installed_gcc = false
-
-      deps = []
-      reqs = []
-
-      fetch_args = [formula_name]
-      fetch_args << "--build-bottle" if !ARGV.include?("--fast") && !ARGV.include?("--no-bottle") && !formula.bottle_disabled?
-      fetch_args << "--force" if ARGV.include? "--cleanup"
-
-      audit_args = [formula_name]
-      audit_args << "--new-formula" if @added_formulae.include? formula_name
-
-      if formula.stable
-        unless satisfied_requirements?(formula, :stable)
-          test "brew", "fetch", "--retry", *fetch_args
-          test "brew", "audit", *audit_args
-          return
-        end
-
-        deps |= formula.stable.deps.to_a.reject(&:optional?)
-        reqs |= formula.stable.requirements.to_a.reject(&:optional?)
-      elsif formula.devel
-        unless satisfied_requirements?(formula, :devel)
-          test "brew", "fetch", "--retry", "--devel", *fetch_args
-          test "brew", "audit", "--devel", *audit_args
-          return
-        end
-      end
-
-      if formula.devel && !ARGV.include?("--HEAD")
-        deps |= formula.devel.deps.to_a.reject(&:optional?)
-        reqs |= formula.devel.requirements.to_a.reject(&:optional?)
-      end
-
-      begin
-        deps.each { |d| d.to_formula.recursive_dependencies }
-      rescue TapFormulaUnavailableError => e
-        raise if e.tap.installed?
-        safe_system "brew", "tap", e.tap.name
-        retry
-      end
-
-      begin
-        deps.each do |dep|
-          CompilerSelector.select_for(dep.to_formula)
-        end
-        CompilerSelector.select_for(formula)
-      rescue CompilerSelectionError => e
-        unless installed_gcc
-          run_as_not_developer { test "brew", "install", "gcc" }
-          installed_gcc = true
-          DevelopmentTools.clear_version_cache
-          retry
-        end
-        skip formula_name
-        puts e.message
-        return
-      end
-
-      conflicts = formula.conflicts
-      formula.recursive_dependencies.each do |dependency|
-        conflicts += dependency.to_formula.conflicts
-      end
-
-      conflicts.each do |conflict|
-        confict_formula = Formulary.factory(conflict.name)
-
-        if confict_formula.installed? && confict_formula.linked_keg.exist?
-          test "brew", "unlink", "--force", conflict.name
-        end
-      end
-
-      installed = Utils.popen_read("brew", "list").split("\n")
-      dependencies = Utils.popen_read("brew", "deps", "--include-build", formula_name).split("\n")
-
-      (installed & dependencies).each do |installed_dependency|
-        installed_dependency_formula = Formulary.factory(installed_dependency)
-        if installed_dependency_formula.installed? &&
-           !installed_dependency_formula.keg_only? &&
-           !installed_dependency_formula.linked_keg.exist?
-          test "brew", "link", installed_dependency
-        end
-      end
-
-      dependencies -= installed
-      unchanged_dependencies = dependencies - @formulae
-      changed_dependences = dependencies - unchanged_dependencies
-
-      runtime_dependencies = Utils.popen_read("brew", "deps", formula_name).split("\n")
-      build_dependencies = dependencies - runtime_dependencies
-      unchanged_build_dependencies = build_dependencies - @formulae
-
-      dependents = Utils.popen_read("brew", "uses", formula_name).split("\n")
-      dependents -= @formulae
-      dependents = dependents.map { |d| Formulary.factory(d) }
-
-      bottled_dependents = dependents.select(&:bottled?)
-      testable_dependents = dependents.select { |d| d.bottled? && d.test_defined? }
-
-      if (deps | reqs).any? { |d| d.name == "mercurial" && d.build? }
-        run_as_not_developer { test "brew", "install", "mercurial" }
-      end
-
-      test "brew", "fetch", "--retry", *unchanged_dependencies unless unchanged_dependencies.empty?
-
-      unless changed_dependences.empty?
-        test "brew", "fetch", "--retry", "--build-bottle", *changed_dependences
-        unless ARGV.include?("--fast")
-          # Install changed dependencies as new bottles so we don't have checksum problems.
-          test "brew", "install", "--build-bottle", *changed_dependences
-          # Run postinstall on them because the tested formula might depend on
-          # this step
-          test "brew", "postinstall", *changed_dependences
-        end
-      end
-      test "brew", "fetch", "--retry", *fetch_args
-      test "brew", "uninstall", "--force", formula_name if formula.installed?
-
-      # shared_*_args are applied to both the main and --devel spec
-      shared_install_args = ["--verbose"]
-      shared_install_args << "--keep-tmp" if ARGV.keep_tmp?
-      # install_args is just for the main (stable, or devel if in a devel-only tap) spec
-      install_args = []
-      install_args << "--build-bottle" if !ARGV.include?("--fast") && !ARGV.include?("--no-bottle") && !formula.bottle_disabled?
-      install_args << "--HEAD" if ARGV.include? "--HEAD"
-
-      # Pass --devel or --HEAD to install in the event formulae lack stable. Supports devel-only/head-only.
-      # head-only should not have devel, but devel-only can have head. Stable can have all three.
-      if devel_only_tap? formula
-        install_args << "--devel"
-        formula_bottled = false
-      elsif head_only_tap? formula
-        install_args << "--HEAD"
-        formula_bottled = false
-      else
-        formula_bottled = formula.bottled?
-      end
-
-      install_args.concat(shared_install_args)
-      install_args << formula_name
-      # Don't care about e.g. bottle failures for dependencies.
-      install_passed = false
-      run_as_not_developer do
-        if !ARGV.include?("--fast") || formula_bottled || formula.bottle_unneeded?
-          test "brew", "install", "--only-dependencies", *install_args unless dependencies.empty?
-          test "brew", "install", *install_args
-          install_passed = steps.last.passed?
-        end
-      end
-      test "brew", "audit", *audit_args
-      if install_passed
-        if formula.stable? && !ARGV.include?("--fast") && !ARGV.include?("--no-bottle") && !formula.bottle_disabled?
-          bottle_args = ["--verbose", "--json", formula_name]
-          bottle_args << "--keep-old" if ARGV.include? "--keep-old"
-          bottle_args << "--skip-relocation" if ARGV.include? "--skip-relocation"
-          bottle_args << "--force-core-tap" if @test_default_formula
-          test "brew", "bottle", *bottle_args
-          bottle_step = steps.last
-          if bottle_step.passed? && bottle_step.output?
-            bottle_filename =
-              bottle_step.output.gsub(%r{.*(\./\S+#{Utils::Bottles.native_regex}).*}m, '\1')
-            bottle_json_filename = bottle_filename.gsub(/\.(\d+\.)?tar\.gz$/, ".json")
-            bottle_merge_args = ["--merge", "--write", "--no-commit", bottle_json_filename]
-            bottle_merge_args << "--keep-old" if ARGV.include? "--keep-old"
-            test "brew", "bottle", *bottle_merge_args
-            test "brew", "uninstall", "--force", formula_name
-            FileUtils.ln bottle_filename, HOMEBREW_CACHE/bottle_filename, force: true
-            @formulae.delete(formula_name)
-            unless unchanged_build_dependencies.empty?
-              test "brew", "uninstall", "--force", *unchanged_build_dependencies
-              unchanged_dependencies -= unchanged_build_dependencies
-            end
-            test "brew", "install", bottle_filename
-          end
-        end
-        shared_test_args = ["--verbose"]
-        shared_test_args << "--keep-tmp" if ARGV.keep_tmp?
-        test "brew", "test", formula_name, *shared_test_args if formula.test_defined?
-        bottled_dependents.each do |dependent|
-          unless dependent.installed?
-            test "brew", "fetch", "--retry", dependent.name
-            next if steps.last.failed?
-            conflicts = dependent.conflicts.map { |c| Formulary.factory(c.name) }.select(&:installed?)
-            dependent.recursive_dependencies.each do |dependency|
-              conflicts += dependency.to_formula.conflicts.map { |c| Formulary.factory(c.name) }.select(&:installed?)
-            end
-            conflicts.each do |conflict|
-              test "brew", "unlink", conflict.name
-            end
-            unless ARGV.include?("--fast")
-              run_as_not_developer { test "brew", "install", dependent.name }
-              next if steps.last.failed?
-            end
-          end
-          next unless dependent.installed?
-          test "brew", "linkage", "--test", dependent.name
-          if testable_dependents.include? dependent
-            test "brew", "test", "--verbose", dependent.name
-          end
-        end
-        test "brew", "uninstall", "--force", formula_name
-      end
-
-      if formula.devel && formula.stable? \
-         && !ARGV.include?("--HEAD") && !ARGV.include?("--fast") \
-         && satisfied_requirements?(formula, :devel)
-        test "brew", "fetch", "--retry", "--devel", *fetch_args
-        run_as_not_developer do
-          test "brew", "install", "--devel", formula_name, *shared_install_args
-        end
-        devel_install_passed = steps.last.passed?
-        test "brew", "audit", "--devel", *audit_args
-        if devel_install_passed
-          test "brew", "test", "--devel", formula_name, *shared_test_args if formula.test_defined?
-          test "brew", "uninstall", "--devel", "--force", formula_name
-        end
-      end
-      test "brew", "uninstall", "--force", *unchanged_dependencies unless unchanged_dependencies.empty?
-    end
-
-    def homebrew
-      @category = __method__
-      return if @skip_homebrew
-
-      if !@tap && (@formulae.empty? || @test_default_formula)
-        # TODO: try to fix this on Linux at some stage.
-        if OS.mac?
-          # test update from origin/master to current commit.
-          test "brew", "update-test"
-          # test no-op update from current commit (to current commit, a no-op).
-          test "brew", "update-test", "--commit=HEAD"
-        end
-
-        test "brew", "style"
-        test "brew", "readall", "--syntax"
-
-        coverage_args = []
-        if ARGV.include?("--coverage")
-          if ENV["JENKINS_HOME"]
-            if OS.mac? && MacOS.version == :sierra
-              coverage_args << "--coverage"
-            end
-          else
-            coverage_args << "--coverage"
-          end
-        end
-
-        test "brew", "tests", "--no-compat"
-        test "brew", "tests", "--generic"
-        test "brew", "tests", "--official-cmd-taps", *coverage_args
-
-        if OS.mac?
-          run_as_not_developer { test "brew", "tap", "caskroom/cask" }
-          test "brew", "cask-tests", *coverage_args
-        end
-      elsif @tap
-        if @tap.name == "homebrew/core"
-          test "brew", "style", @tap.name
-        end
-        test "brew", "readall", "--aliases", @tap.name
-      end
-    end
-
-    def cleanup_git
-      git "gc", "--auto"
-      test "git", "clean", "-ffdx", "--exclude=Library/Taps"
-
-      Tap.names.each do |tap|
-        next if tap == "homebrew/core"
-        next if tap == @tap.to_s
-        safe_system "brew", "untap", tap
-      end
-
-      Formula.installed.each do |formula|
-        safe_system "brew", "uninstall", "--force", formula
-      end
-      safe_system "brew", "prune"
-
-      unless @repository == HOMEBREW_REPOSITORY
-        HOMEBREW_REPOSITORY.cd do
-          safe_system "git", "checkout", "-f", "master"
-          safe_system "git", "reset", "--hard", "origin/master"
-          safe_system "git", "clean", "-ffdx", "--exclude=Library/Taps"
-        end
-      end
-
-      Pathname.glob("#{HOMEBREW_LIBRARY}/Taps/*/*").each do |git_repo|
-        next if @repository == git_repo
-        git_repo.cd do
-          safe_system "git", "checkout", "-f", "master"
-          safe_system "git", "reset", "--hard", "origin/master"
-        end
-      end
-    end
-
-    def cleanup_before
-      @category = __method__
-      return unless ARGV.include? "--cleanup"
-      git "stash"
-      git "am", "--abort"
-      git "rebase", "--abort"
-      unless ARGV.include? "--no-pull"
-        git "checkout", "-f", "master"
-        git "reset", "--hard", "origin/master"
-      end
-
-      cleanup_git
-
-      pr_locks = "#{@repository}/.git/refs/remotes/*/pr/*/*.lock"
-      Dir.glob(pr_locks) { |lock| FileUtils.rm_rf lock }
-    end
-
-    def cleanup_after
-      @category = __method__
-
-      if @start_branch && !@start_branch.empty? && \
-         (ARGV.include?("--cleanup") || @url || @hash)
-        checkout_args = [@start_branch]
-        checkout_args << "-f" if ARGV.include? "--cleanup"
-        test "git", "checkout", *checkout_args
-      end
-
-      if ARGV.include? "--cleanup"
-        git "reset", "--hard", "origin/master"
-        git "stash", "pop"
-        test "brew", "cleanup", "--prune=7"
-
-        cleanup_git
-
-        if ARGV.include? "--local"
-          FileUtils.rm_rf ENV["HOMEBREW_HOME"]
-          FileUtils.rm_rf ENV["HOMEBREW_LOGS"]
-        end
-      end
-
-      FileUtils.rm_rf @brewbot_root unless ARGV.include? "--keep-logs"
-    end
-
-    def test(*args)
-      options = args.last.is_a?(Hash) ? args.pop : {}
-      options[:repository] = @repository
-      step = Step.new self, args, options
-      step.run
-      steps << step
-      step
-    end
-
-    def check_results
-      steps.all? do |step|
-        case step.status
-        when :passed  then true
-        when :running then raise
-        when :failed  then false
-        end
-      end
-    end
-
-    def formulae
-      changed_formulae_dependents = {}
-
-      @formulae.each do |formula|
-        formula_dependencies = Utils.popen_read("brew", "deps", "--full-name", "--include-build", formula).split("\n")
-        unchanged_dependencies = formula_dependencies - @formulae
-        changed_dependences = formula_dependencies - unchanged_dependencies
-        changed_dependences.each do |changed_formula|
-          changed_formulae_dependents[changed_formula] ||= 0
-          changed_formulae_dependents[changed_formula] += 1
-        end
-      end
-
-      changed_formulae = changed_formulae_dependents.sort do |a1, a2|
-        a2[1].to_i <=> a1[1].to_i
-      end
-      changed_formulae.map!(&:first)
-      unchanged_formulae = @formulae - changed_formulae
-      changed_formulae + unchanged_formulae
-    end
-
-    def head_only_tap?(formula)
-      formula.head && formula.devel.nil? && formula.stable.nil? && formula.tap == "homebrew/homebrew-head-only"
-    end
-
-    def devel_only_tap?(formula)
-      formula.devel && formula.stable.nil? && formula.tap == "homebrew/homebrew-devel-only"
-    end
-
-    def run
-      cleanup_before
-      begin
-        download
-        setup
-        homebrew
-        formulae.each do |f|
-          formula(f)
-        end
-      ensure
-        cleanup_after
-      end
-      check_results
-    end
-  end
-
-  def test_ci_upload(tap)
-    # Don't trust formulae we're uploading
-    ENV["HOMEBREW_DISABLE_LOAD_FORMULA"] = "1"
-
-    bintray_user = ENV["BINTRAY_USER"]
-    bintray_key = ENV["BINTRAY_KEY"]
-    if !bintray_user || !bintray_key
-      raise "Missing BINTRAY_USER or BINTRAY_KEY variables!"
-    end
-
-    # Don't pass keys/cookies to subprocesses
-    ENV["BINTRAY_KEY"] = nil
-    ENV["HUDSON_SERVER_COOKIE"] = nil
-    ENV["JENKINS_SERVER_COOKIE"] = nil
-    ENV["HUDSON_COOKIE"] = nil
-    ENV["COVERALLS_REPO_TOKEN"] = nil
-
-    ARGV << "--verbose"
-
-    bottles = Dir["*.bottle*.*"]
-    if bottles.empty?
-      jenkins = ENV["JENKINS_HOME"]
-      job = ENV["UPSTREAM_JOB_NAME"]
-      id = ENV["UPSTREAM_BUILD_ID"]
-      raise "Missing Jenkins variables!" if !jenkins || !job || !id
-
-      bottles = Dir["#{jenkins}/jobs/#{job}/configurations/axis-version/*/builds/#{id}/archive/*.bottle*.*"]
-      return if bottles.empty?
-
-      FileUtils.cp bottles, Dir.pwd, verbose: true
-    end
-
-    json_files = Dir.glob("*.bottle.json")
-    bottles_hash = json_files.reduce({}) do |hash, json_file|
-      deep_merge_hashes hash, Utils::JSON.load(IO.read(json_file))
-    end
-
-    first_formula_name = bottles_hash.keys.first
-    tap = Tap.fetch(first_formula_name.rpartition("/").first.chuzzle || "homebrew/core")
-
-    ENV["GIT_AUTHOR_NAME"] = ENV["GIT_COMMITTER_NAME"] = "BrewTestBot"
-    ENV["GIT_AUTHOR_EMAIL"] = ENV["GIT_COMMITTER_EMAIL"] = "brew-test-bot@googlegroups.com"
-    ENV["GIT_WORK_TREE"] = tap.path
-    ENV["GIT_DIR"] = "#{ENV["GIT_WORK_TREE"]}/.git"
-
-    quiet_system "git", "am", "--abort"
-    quiet_system "git", "rebase", "--abort"
-    safe_system "git", "checkout", "-f", "master"
-    safe_system "git", "reset", "--hard", "origin/master"
-    safe_system "brew", "update"
-
-    if (pr = ENV["UPSTREAM_PULL_REQUEST"])
-      pull_pr = "https://github.com/#{tap.user}/homebrew-#{tap.repo}/pull/#{pr}"
-      safe_system "brew", "pull", "--clean", pull_pr
-    end
-
-    if ENV["UPSTREAM_BOTTLE_KEEP_OLD"] || ENV["BOT_PARAMS"].to_s.include?("--keep-old")
-      system "brew", "bottle", "--merge", "--write", "--keep-old", *json_files
-    else
-      system "brew", "bottle", "--merge", "--write", *json_files
-    end
-
-    remote = "git@github.com:BrewTestBot/homebrew-#{tap.repo}.git"
-    git_tag = if pr
-      "pr-#{pr}"
-    elsif (upstream_number = ENV["UPSTREAM_BUILD_NUMBER"])
-      "testing-#{upstream_number}"
-    elsif (number = ENV["BUILD_NUMBER"])
-      "other-#{number}"
-    end
-    if git_tag
-      safe_system "git", "push", "--force", remote, "master:master", ":refs/tags/#{git_tag}"
-    end
-
-    formula_packaged = {}
-
-    bottles_hash.each do |formula_name, bottle_hash|
-      version = bottle_hash["formula"]["pkg_version"]
-      bintray_package = bottle_hash["bintray"]["package"]
-      bintray_repo = bottle_hash["bintray"]["repository"]
-      bintray_repo_url = "https://api.bintray.com/packages/homebrew/#{bintray_repo}"
-
-      bottle_hash["bottle"]["tags"].each do |_tag, tag_hash|
-        filename = tag_hash["filename"]
-        if system "curl", "-I", "--silent", "--fail", "--output", "/dev/null",
-                  "#{BottleSpecification::DEFAULT_DOMAIN}/#{bintray_repo}/#{filename}"
-          raise <<-EOS.undent
-            #{filename} is already published. Please remove it manually from
-            https://bintray.com/homebrew/#{bintray_repo}/#{bintray_package}/view#files
-          EOS
-        end
-
-        unless formula_packaged[formula_name]
-          package_url = "#{bintray_repo_url}/#{bintray_package}"
-          unless system "curl", "--silent", "--fail", "--output", "/dev/null", package_url
-            package_blob = <<-EOS.undent
-              {"name": "#{bintray_package}",
-               "public_download_numbers": true,
-               "public_stats": true}
-            EOS
-            curl "--silent", "--fail", "-u#{bintray_user}:#{bintray_key}",
-                 "-H", "Content-Type: application/json",
-                 "-d", package_blob, bintray_repo_url
-            puts
-          end
-          formula_packaged[formula_name] = true
-        end
-
-        content_url = "https://api.bintray.com/content/homebrew"
-        content_url += "/#{bintray_repo}/#{bintray_package}/#{version}/#{filename}"
-        content_url += "?override=1"
-        curl "--silent", "--fail", "-u#{bintray_user}:#{bintray_key}",
-             "-T", filename, content_url
-        puts
-      end
-    end
-
-    if git_tag
-      safe_system "git", "tag", "--force", git_tag
-      safe_system "git", "push", "--force", remote, "master:master", "refs/tags/#{git_tag}"
-    end
-  end
-
-  def sanitize_argv_and_env
-    if Pathname.pwd == HOMEBREW_PREFIX && ARGV.include?("--cleanup")
-      odie "cannot use --cleanup from HOMEBREW_PREFIX as it will delete all output."
-    end
-
-    ENV["HOMEBREW_DEVELOPER"] = "1"
-    ENV["HOMEBREW_SANDBOX"] = "1"
-    ENV["HOMEBREW_NO_EMOJI"] = "1"
-    ENV["HOMEBREW_FAIL_LOG_LINES"] = "150"
-    ENV["HOMEBREW_EXPERIMENTAL_FILTER_FLAGS_ON_DEPS"] = "1"
-    ENV["PATH"] = "#{HOMEBREW_PREFIX}/bin:#{HOMEBREW_PREFIX}/sbin:#{ENV["PATH"]}"
-
-    travis = !ENV["TRAVIS"].nil?
-    if travis
-      ARGV << "--verbose"
-      ENV["HOMEBREW_VERBOSE_USING_DOTS"] = "1"
-    end
-
-    # Only report coverage if build runs on macOS and this is indeed Homebrew,
-    # as we don't want this to be averaged with inferior Linux test coverage.
-    if OS.mac? && (ENV["COVERALLS_REPO_TOKEN"] || ENV["CODECOV_TOKEN"])
-      ARGV << "--coverage"
-    end
-
-    travis_pr = ENV["TRAVIS_PULL_REQUEST"] && ENV["TRAVIS_PULL_REQUEST"] != "false"
-    jenkins_pr = !ENV["ghprbPullLink"].nil?
-    jenkins_branch = !ENV["GIT_COMMIT"].nil?
-
-    if ARGV.include?("--ci-auto")
-      if travis_pr || jenkins_pr
-        ARGV << "--ci-pr"
-      elsif travis || jenkins_branch
-        ARGV << "--ci-master"
-      else
-        ARGV << "--ci-testing"
-      end
-    end
-
-    if ARGV.include?("--ci-master") || ARGV.include?("--ci-pr") \
-       || ARGV.include?("--ci-testing")
-      ARGV << "--cleanup" if ENV["JENKINS_HOME"]
-      ARGV << "--junit" << "--local" << "--test-default-formula"
-    end
-
-    if ARGV.include? "--ci-master"
-      ARGV << "--fast"
-    end
-
-    if ARGV.include? "--local"
-      ENV["HOMEBREW_CACHE"] = "#{ENV["HOME"]}/Library/Caches/Homebrew"
-      mkdir_p ENV["HOMEBREW_CACHE"]
-      ENV["HOMEBREW_HOME"] = ENV["HOME"] = "#{Dir.pwd}/home"
-      mkdir_p ENV["HOME"]
-      ENV["HOMEBREW_LOGS"] = "#{Dir.pwd}/logs"
-    end
-  end
-
-  def test_bot
-    sanitize_argv_and_env
-
-    tap = resolve_test_tap
-    # Tap repository if required, this is done before everything else
-    # because Formula parsing and/or git commit hash lookup depends on it.
-    # At the same time, make sure Tap is not a shallow clone.
-    # bottle rebuild and bottle upload rely on full clone.
-    safe_system "brew", "tap", tap.name, "--full" if tap
-
-    if ARGV.include? "--ci-upload"
-      return test_ci_upload(tap)
-    end
-
-    tests = []
-    any_errors = false
-    skip_homebrew = ARGV.include?("--skip-homebrew")
-    if ARGV.named.empty?
-      # With no arguments just build the most recent commit.
-      current_test = Test.new("HEAD", tap: tap, skip_homebrew: skip_homebrew)
-      any_errors = !current_test.run
-      tests << current_test
-    else
-      ARGV.named.each do |argument|
-        test_error = false
-        begin
-          current_test = Test.new(argument, tap: tap, skip_homebrew: skip_homebrew)
-          skip_homebrew = true
-        rescue ArgumentError => e
-          test_error = true
-          ofail e.message
-        else
-          test_error = !current_test.run
-          tests << current_test
-        end
-        any_errors ||= test_error
-      end
-    end
-
-    if ARGV.include? "--junit"
-      xml_document = REXML::Document.new
-      xml_document << REXML::XMLDecl.new
-      testsuites = xml_document.add_element "testsuites"
-
-      tests.each do |test|
-        testsuite = testsuites.add_element "testsuite"
-        testsuite.add_attribute "name", "brew-test-bot.#{Utils::Bottles.tag}"
-        testsuite.add_attribute "tests", test.steps.count
-
-        test.steps.each do |step|
-          testcase = testsuite.add_element "testcase"
-          testcase.add_attribute "name", step.command_short
-          testcase.add_attribute "status", step.status
-          testcase.add_attribute "time", step.time
-
-          next unless step.output?
-          output = sanitize_output_for_xml(step.output)
-          cdata = REXML::CData.new output
-
-          if step.passed?
-            elem = testcase.add_element "system-out"
-          else
-            elem = testcase.add_element "failure"
-            elem.add_attribute "message", "#{step.status}: #{step.command.join(" ")}"
-          end
-
-          elem << cdata
-        end
-      end
-
-      open("brew-test-bot.xml", "w") do |xml_file|
-        pretty_print_indent = 2
-        xml_document.write(xml_file, pretty_print_indent)
-      end
-    end
-  ensure
-    if ARGV.include? "--clean-cache"
-      HOMEBREW_CACHE.children.each(&:rmtree)
-    else
-      Dir.glob("*.bottle*.tar.gz") do |bottle_file|
-        FileUtils.rm_f HOMEBREW_CACHE/bottle_file
-      end
-    end
-
-    Homebrew.failed = any_errors
-  end
-
-  def sanitize_output_for_xml(output)
-    unless output.empty?
-      # Remove invalid XML CData characters from step output.
-      invalid_xml_pat = /[^\x09\x0A\x0D\x20-\uD7FF\uE000-\uFFFD\u{10000}-\u{10FFFF}]/
-      output = output.gsub(invalid_xml_pat, "\uFFFD")
-
-      # Truncate to 1MB to avoid hitting CI limits
-      if output.bytesize > MAX_STEP_OUTPUT_SIZE
-        output = truncate_text_to_approximate_size(output, MAX_STEP_OUTPUT_SIZE, front_weight: 0.0)
-        output = "truncated output to 1MB:\n" + output
-      end
-    end
-    output
-  end
-end
diff --git a/Library/Homebrew/dev-cmd/test.rb b/Library/Homebrew/dev-cmd/test.rb
index a80fa5e4f..c20edf804 100644
--- a/Library/Homebrew/dev-cmd/test.rb
+++ b/Library/Homebrew/dev-cmd/test.rb
@@ -1,5 +1,5 @@
 #:  * `test` [`--devel`|`--HEAD`] [`--debug`] [`--keep-tmp`] <formula>:
-#:    A few formulae provide a test method. `brew test` <formula> runs this
+#:    Most formulae provide a test method. `brew test` <formula> runs this
 #:    test method. There is no standard output or return code, but it should
 #:    generally indicate to the user if something is wrong with the installed
 #:    formula.
diff --git a/Library/Homebrew/dev-cmd/tests.rb b/Library/Homebrew/dev-cmd/tests.rb
index aa2a3bff9..9b15f9f3e 100644
--- a/Library/Homebrew/dev-cmd/tests.rb
+++ b/Library/Homebrew/dev-cmd/tests.rb
@@ -6,7 +6,7 @@ require "tap"
 
 module Homebrew
   def tests
-    (HOMEBREW_LIBRARY/"Homebrew/test").cd do
+    (HOMEBREW_LIBRARY/"Homebrew").cd do
       ENV["HOMEBREW_NO_ANALYTICS_THIS_RUN"] = "1"
       ENV["HOMEBREW_DEVELOPER"] = "1"
       ENV["TESTOPTS"] = "-v" if ARGV.verbose?
@@ -19,9 +19,11 @@ module Homebrew
 
       if ARGV.include? "--coverage"
         ENV["HOMEBREW_TESTS_COVERAGE"] = "1"
-        FileUtils.rm_f "coverage/.resultset.json"
+        FileUtils.rm_f "test/coverage/.resultset.json"
       end
 
+      ENV["BUNDLE_GEMFILE"] = "#{Dir.pwd}/test/Gemfile"
+
       # Override author/committer as global settings might be invalid and thus
       # will cause silent failure during the setup of dummy Git repositories.
       %w[AUTHOR COMMITTER].each do |role|
@@ -37,16 +39,26 @@ module Homebrew
       # Make it easier to reproduce test runs.
       ENV["SEED"] = ARGV.next if ARGV.include? "--seed"
 
+      files = Dir["test/test_*.rb"]
+      files -= Dir["test/test_os_mac_*.rb"] unless OS.mac?
+
+      opts = []
+      opts << "--serialize-stdout" if ENV["CI"]
+
       args = []
       args << "--trace" if ARGV.include? "--trace"
+
       if ARGV.value("only")
         ENV["HOMEBREW_TESTS_ONLY"] = "1"
         test_name, test_method = ARGV.value("only").split("/", 2)
-        args << "TEST=test_#{test_name}.rb"
-        args << "TESTOPTS=--name=test_#{test_method}" if test_method
+        files = ["test/test_#{test_name}.rb"]
+        args << "--name=test_#{test_method}" if test_method
       end
+
       args += ARGV.named.select { |v| v[/^TEST(OPTS)?=/] }
-      system "bundle", "exec", "rake", "test", *args
+
+      system "bundle", "exec", "parallel_test", *opts,
+        "--", *args, "--", *files
 
       Homebrew.failed = !$?.success?
 
diff --git a/Library/Homebrew/dev-cmd/update-test.rb b/Library/Homebrew/dev-cmd/update-test.rb
index bcf8020e4..18980b691 100644
--- a/Library/Homebrew/dev-cmd/update-test.rb
+++ b/Library/Homebrew/dev-cmd/update-test.rb
@@ -1,9 +1,9 @@
-#:  * `update-test` [`--commit=<sha1>`] [`--before=<date>`] [`--keep-tmp`]:
+#:  * `update-test` [`--commit=<commit>`] [`--before=<date>`] [`--keep-tmp`]:
 #:    Runs a test of `brew update` with a new repository clone.
 #:
 #:    If no arguments are passed, use `origin/master` as the start commit.
 #:
-#:    If `--commit=<sha1>` is passed, use `<sha1>` as the start commit.
+#:    If `--commit=<commit>` is passed, use `<commit>` as the start commit.
 #:
 #:    If `--before=<date>` is passed, use the commit at `<date>` as the
 #:    start commit.
@@ -14,18 +14,18 @@
 module Homebrew
   def update_test
     cd HOMEBREW_REPOSITORY
-    start_sha1 = if commit = ARGV.value("commit")
+    start_commit = if commit = ARGV.value("commit")
       commit
     elsif date = ARGV.value("before")
       Utils.popen_read("git", "rev-list", "-n1", "--before=#{date}", "origin/master").chomp
     else
       Utils.popen_read("git", "rev-parse", "origin/master").chomp
     end
-    start_sha1 = Utils.popen_read("git", "rev-parse", start_sha1).chomp
-    end_sha1 = Utils.popen_read("git", "rev-parse", "HEAD").chomp
+    start_commit = Utils.popen_read("git", "rev-parse", start_commit).chomp
+    end_commit = Utils.popen_read("git", "rev-parse", "HEAD").chomp
 
-    puts "Start commit: #{start_sha1}"
-    puts "End   commit: #{end_sha1}"
+    puts "Start commit: #{start_commit}"
+    puts "End   commit: #{end_commit}"
 
     mktemp("update-test") do |staging|
       staging.retain! if ARGV.keep_tmp?
@@ -39,12 +39,12 @@ module Homebrew
       safe_system "git", "clone", "--local", "--bare", "#{HOMEBREW_REPOSITORY}/.git", "remote.git"
       safe_system "git", "config", "remote.origin.url", "#{curdir}/remote.git"
 
-      # force push origin to end_sha1
-      safe_system "git", "checkout", "-B", "master", end_sha1
+      # force push origin to end_commit
+      safe_system "git", "checkout", "-B", "master", end_commit
       safe_system "git", "push", "--force", "origin", "master"
 
-      # set test copy to start_sha1
-      safe_system "git", "reset", "--hard", start_sha1
+      # set test copy to start_commit
+      safe_system "git", "reset", "--hard", start_commit
 
       # update ENV["PATH"]
       ENV["PATH"] = "#{curdir}/bin:/usr/local/bin:/usr/bin:/bin"
@@ -52,13 +52,13 @@ module Homebrew
       # run brew update
       oh1 "Running brew update..."
       safe_system "brew", "update", "--verbose"
-      actual_end_sha1 = Utils.popen_read("git", "rev-parse", "master").chomp
-      if start_sha1 != end_sha1 && start_sha1 == actual_end_sha1
+      actual_end_commit = Utils.popen_read("git", "rev-parse", "master").chomp
+      if start_commit != end_commit && start_commit == actual_end_commit
         raise <<-EOS.undent
           brew update didn't update master!
-          Start commit:        #{start_sha1}
-          Expected end commit: #{end_sha1}
-          Actual end commit:   #{actual_end_sha1}
+          Start commit:        #{start_commit}
+          Expected end commit: #{end_commit}
+          Actual end commit:   #{actual_end_commit}
         EOS
       end
     end
diff --git a/Library/Homebrew/development_tools.rb b/Library/Homebrew/development_tools.rb
index 14e1a07f7..7221e5b52 100644
--- a/Library/Homebrew/development_tools.rb
+++ b/Library/Homebrew/development_tools.rb
@@ -22,8 +22,7 @@ class DevelopmentTools
     def installation_instructions
       "Install Clang or brew install gcc"
     end
-    alias_method :custom_installation_instructions,
-                 :installation_instructions
+    alias custom_installation_instructions installation_instructions
 
     def default_cc
       cc = DevelopmentTools.locate "cc"
@@ -48,7 +47,7 @@ class DevelopmentTools
           `#{path} --version 2>/dev/null`[/build (\d{4,})/, 1].to_i
         end
     end
-    alias_method :gcc_4_0_build_version, :gcc_40_build_version
+    alias gcc_4_0_build_version gcc_40_build_version
 
     def gcc_42_build_version
       @gcc_42_build_version ||=
@@ -59,7 +58,7 @@ class DevelopmentTools
           end
         end
     end
-    alias_method :gcc_build_version, :gcc_42_build_version
+    alias gcc_build_version gcc_42_build_version
 
     def clang_version
       @clang_version ||=
diff --git a/Library/Homebrew/diagnostic.rb b/Library/Homebrew/diagnostic.rb
index 650ff3eab..743c653d2 100644
--- a/Library/Homebrew/diagnostic.rb
+++ b/Library/Homebrew/diagnostic.rb
@@ -39,15 +39,11 @@ module Homebrew
         vols = get_mounts path
 
         # no volume found
-        if vols.empty?
-          return -1
-        end
+        return -1 if vols.empty?
 
         vol_index = @volumes.index(vols[0])
         # volume not found in volume list
-        if vol_index.nil?
-          return -1
-        end
+        return -1 if vol_index.nil?
         vol_index
       end
 
@@ -82,8 +78,8 @@ module Homebrew
         end
       end
 
-      def inject_file_list(list, str)
-        list.inject(str) { |s, f| s << "    #{f}\n" }
+      def inject_file_list(list, string)
+        list.inject(string) { |a, e| a << "    #{e}\n" }
       end
       ############# END HELPERS
 
@@ -599,7 +595,7 @@ module Homebrew
         EOS
       end
 
-      def check_DYLD_vars
+      def check_dyld_vars
         dyld_vars = ENV.keys.grep(/^DYLD_/)
         return if dyld_vars.empty?
 
@@ -758,7 +754,7 @@ module Homebrew
               cd #{HOMEBREW_REPOSITORY}
               git remote add origin https://github.com/Homebrew/brew.git
           EOS
-        elsif origin !~ /Homebrew\/brew(\.git)?$/
+        elsif origin !~ %r{Homebrew/brew(\.git)?$}
           <<-EOS.undent
             Suspicious git origin remote found.
 
diff --git a/Library/Homebrew/download_strategy.rb b/Library/Homebrew/download_strategy.rb
index cabb22c22..1775e4e38 100644
--- a/Library/Homebrew/download_strategy.rb
+++ b/Library/Homebrew/download_strategy.rb
@@ -158,14 +158,13 @@ class VCSDownloadStrategy < AbstractDownloadStrategy
 
     version.update_commit(last_commit) if head?
 
-    if @ref_type == :tag && @revision && current_revision
-      unless current_revision == @revision
-        raise <<-EOS.undent
-          #{@ref} tag should be #{@revision}
-          but is actually #{current_revision}
-        EOS
-      end
-    end
+    return unless @ref_type == :tag
+    return unless @revision && current_revision
+    return if current_revision == @revision
+    raise <<-EOS.undent
+      #{@ref} tag should be #{@revision}
+      but is actually #{current_revision}
+    EOS
   end
 
   def fetch_last_commit
@@ -336,14 +335,14 @@ class CurlDownloadStrategy < AbstractFileDownloadStrategy
       rescue ErrorDuringExecution
         # 33 == range not supported
         # try wiping the incomplete download and retrying once
-        if $?.exitstatus == 33 && had_incomplete_download
-          ohai "Trying a full download"
-          temporary_path.unlink
-          had_incomplete_download = false
-          retry
-        else
+        unless $?.exitstatus == 33 && had_incomplete_download
           raise CurlDownloadStrategyError, @url
         end
+
+        ohai "Trying a full download"
+        temporary_path.unlink
+        had_incomplete_download = false
+        retry
       end
       ignore_interrupts { temporary_path.rename(cached_location) }
     end
@@ -561,7 +560,7 @@ class SubversionDownloadStrategy < VCSDownloadStrategy
     Utils.popen_read("svn", "info", cached_location.to_s).strip[/^URL: (.+)$/, 1]
   end
 
-  def get_externals
+  def externals
     Utils.popen_read("svn", "propget", "svn:externals", @url).chomp.each_line do |line|
       name, url = line.split(/\s+/)
       yield name, url
@@ -601,14 +600,14 @@ class SubversionDownloadStrategy < VCSDownloadStrategy
       main_revision = @ref[:trunk]
       fetch_repo cached_location, @url, main_revision, true
 
-      get_externals do |external_name, external_url|
+      externals do |external_name, external_url|
         fetch_repo cached_location+external_name, external_url, @ref[external_name], true
       end
     else
       fetch_repo cached_location, @url
     end
   end
-  alias_method :update, :clone_repo
+  alias update clone_repo
 end
 
 class GitDownloadStrategy < VCSDownloadStrategy
@@ -663,19 +662,19 @@ class GitDownloadStrategy < VCSDownloadStrategy
     @shallow && support_depth?
   end
 
-  def is_shallow_clone?
+  def shallow_dir?
     git_dir.join("shallow").exist?
   end
 
   def support_depth?
-    @ref_type != :revision && SHALLOW_CLONE_WHITELIST.any? { |rx| rx === @url }
+    @ref_type != :revision && SHALLOW_CLONE_WHITELIST.any? { |regex| @url =~ regex }
   end
 
   def git_dir
     cached_location.join(".git")
   end
 
-  def has_ref?
+  def ref?
     quiet_system "git", "--git-dir", git_dir, "rev-parse", "-q", "--verify", "#{@ref}^{commit}"
   end
 
@@ -696,7 +695,8 @@ class GitDownloadStrategy < VCSDownloadStrategy
     args << "--depth" << "1" if shallow_clone?
 
     case @ref_type
-    when :branch, :tag then args << "--branch" << @ref
+    when :branch, :tag
+      args << "--branch" << @ref
     end
 
     args << @url << cached_location
@@ -716,12 +716,12 @@ class GitDownloadStrategy < VCSDownloadStrategy
   end
 
   def update_repo
-    if @ref_type == :branch || !has_ref?
-      if !shallow_clone? && is_shallow_clone?
-        quiet_safe_system "git", "fetch", "origin", "--unshallow"
-      else
-        quiet_safe_system "git", "fetch", "origin"
-      end
+    return unless @ref_type == :branch || !ref?
+
+    if !shallow_clone? && shallow_dir?
+      quiet_safe_system "git", "fetch", "origin", "--unshallow"
+    else
+      quiet_safe_system "git", "fetch", "origin"
     end
   end
 
@@ -741,9 +741,11 @@ class GitDownloadStrategy < VCSDownloadStrategy
 
   def reset_args
     ref = case @ref_type
-          when :branch then "origin/#{@ref}"
-          when :revision, :tag then @ref
-          end
+    when :branch
+      "origin/#{@ref}"
+    when :revision, :tag
+      @ref
+    end
 
     %W[reset --hard #{ref}]
   end
@@ -795,10 +797,10 @@ end
 class GitHubGitDownloadStrategy < GitDownloadStrategy
   def initialize(name, resource)
     super
-    if @url =~ %r{^https?://github\.com/([^/]+)/([^/]+)\.git$}
-      @user = $1
-      @repo = $2
-    end
+
+    return unless %r{^https?://github\.com/(?<user>[^/]+)/(?<repo>[^/]+)\.git$} =~ @url
+    @user = user
+    @repo = repo
   end
 
   def github_last_commit
@@ -1021,9 +1023,9 @@ class DownloadStrategyDetector
   def self.detect(url, strategy = nil)
     if strategy.nil?
       detect_from_url(url)
-    elsif Class === strategy && strategy < AbstractDownloadStrategy
+    elsif strategy.is_a?(Class) && strategy < AbstractDownloadStrategy
       strategy
-    elsif Symbol === strategy
+    elsif strategy.is_a?(Symbol)
       detect_from_symbol(strategy)
     else
       raise TypeError,
diff --git a/Library/Homebrew/emoji.rb b/Library/Homebrew/emoji.rb
index ade330947..8c58ca895 100644
--- a/Library/Homebrew/emoji.rb
+++ b/Library/Homebrew/emoji.rb
@@ -17,7 +17,7 @@ module Emoji
     def enabled?
       !ENV["HOMEBREW_NO_EMOJI"]
     end
-    alias_method :generic_enabled?, :enabled?
+    alias generic_enabled? enabled?
   end
 end
 
diff --git a/Library/Homebrew/extend/ARGV.rb b/Library/Homebrew/extend/ARGV.rb
index d9f599877..c217ed8a5 100644
--- a/Library/Homebrew/extend/ARGV.rb
+++ b/Library/Homebrew/extend/ARGV.rb
@@ -30,7 +30,7 @@ module HomebrewArgvExtension
         if f.any_version_installed?
           tab = Tab.for_formula(f)
           resolved_spec = spec(nil) || tab.spec
-          f.set_active_spec(resolved_spec) if f.send(resolved_spec)
+          f.active_spec = resolved_spec if f.send(resolved_spec)
           f.build = tab
           if f.head? && tab.tabfile
             k = Keg.new(tab.tabfile.parent)
@@ -88,11 +88,11 @@ module HomebrewArgvExtension
             Formulary.from_rack(rack)
           end
 
-          if (prefix = f.installed_prefix).directory?
-            Keg.new(prefix)
-          else
+          unless (prefix = f.installed_prefix).directory?
             raise MultipleVersionsInstalledError, rack.basename
           end
+
+          Keg.new(prefix)
         end
       rescue FormulaUnavailableError
         raise <<-EOS.undent
@@ -216,7 +216,7 @@ module HomebrewArgvExtension
   end
 
   def build_all_from_source?
-    !!ENV["HOMEBREW_BUILD_FROM_SOURCE"]
+    !ENV["HOMEBREW_BUILD_FROM_SOURCE"].nil?
   end
 
   # Whether a given formula should be built from source during the current
diff --git a/Library/Homebrew/extend/ENV/shared.rb b/Library/Homebrew/extend/ENV/shared.rb
index 447e4dd29..909dc4f94 100644
--- a/Library/Homebrew/extend/ENV/shared.rb
+++ b/Library/Homebrew/extend/ENV/shared.rb
@@ -289,12 +289,11 @@ module SharedEnvExtension
       EOS
     end
 
-    unless gcc_formula.opt_prefix.exist?
-      raise <<-EOS.undent
-      The requested Homebrew GCC was not installed. You must:
-        brew install #{gcc_formula.full_name}
-      EOS
-    end
+    return if gcc_formula.opt_prefix.exist?
+    raise <<-EOS.undent
+    The requested Homebrew GCC was not installed. You must:
+      brew install #{gcc_formula.full_name}
+    EOS
   end
 
   def permit_arch_flags; end
@@ -328,9 +327,8 @@ module SharedEnvExtension
   end
 
   def check_for_compiler_universal_support
-    if homebrew_cc =~ GNU_GCC_REGEXP
-      raise "Non-Apple GCC can't build universal binaries"
-    end
+    return unless homebrew_cc =~ GNU_GCC_REGEXP
+    raise "Non-Apple GCC can't build universal binaries"
   end
 
   def gcc_with_cxx11_support?(cc)
diff --git a/Library/Homebrew/extend/ENV/std.rb b/Library/Homebrew/extend/ENV/std.rb
index a9b2358b1..27dc95d29 100644
--- a/Library/Homebrew/extend/ENV/std.rb
+++ b/Library/Homebrew/extend/ENV/std.rb
@@ -42,18 +42,17 @@ module Stdenv
     end
 
     # Os is the default Apple uses for all its stuff so let's trust them
-    set_cflags "-Os #{SAFE_CFLAGS_FLAGS}"
+    define_cflags "-Os #{SAFE_CFLAGS_FLAGS}"
 
     append "LDFLAGS", "-Wl,-headerpad_max_install_names"
 
     send(compiler)
 
-    if cc =~ GNU_GCC_REGEXP
-      gcc_formula = gcc_version_formula($&)
-      append_path "PATH", gcc_formula.opt_bin.to_s
-    end
+    return unless cc =~ GNU_GCC_REGEXP
+    gcc_formula = gcc_version_formula($&)
+    append_path "PATH", gcc_formula.opt_bin.to_s
   end
-  alias_method :generic_setup_build_environment, :setup_build_environment
+  alias generic_setup_build_environment setup_build_environment
 
   def homebrew_extra_pkg_config_paths
     []
@@ -84,7 +83,7 @@ module Stdenv
 
     old
   end
-  alias_method :j1, :deparallelize
+  alias j1 deparallelize
 
   # These methods are no-ops for compatibility.
   %w[fast O4 Og].each { |opt| define_method(opt) {} }
@@ -112,13 +111,13 @@ module Stdenv
     super
     set_cpu_cflags "-march=nocona -mssse3"
   end
-  alias_method :gcc_4_0_1, :gcc_4_0
+  alias gcc_4_0_1 gcc_4_0
 
   def gcc
     super
     set_cpu_cflags
   end
-  alias_method :gcc_4_2, :gcc
+  alias gcc_4_2 gcc
 
   GNU_GCC_VERSIONS.each do |n|
     define_method(:"gcc-#{n}") do
@@ -137,21 +136,21 @@ module Stdenv
   end
 
   def minimal_optimization
-    set_cflags "-Os #{SAFE_CFLAGS_FLAGS}"
+    define_cflags "-Os #{SAFE_CFLAGS_FLAGS}"
   end
-  alias_method :generic_minimal_optimization, :minimal_optimization
+  alias generic_minimal_optimization minimal_optimization
 
   def no_optimization
-    set_cflags SAFE_CFLAGS_FLAGS
+    define_cflags SAFE_CFLAGS_FLAGS
   end
-  alias_method :generic_no_optimization, :no_optimization
+  alias generic_no_optimization no_optimization
 
   def libxml2
   end
 
   def x11
   end
-  alias_method :libpng, :x11
+  alias libpng x11
 
   # we've seen some packages fail to build when warnings are disabled!
   def enable_warnings
@@ -174,10 +173,10 @@ module Stdenv
     append_to_cflags Hardware::CPU.universal_archs.as_arch_flags
     append "LDFLAGS", Hardware::CPU.universal_archs.as_arch_flags
 
-    if compiler != :clang && Hardware.is_32_bit?
-      # Can't mix "-march" for a 32-bit CPU  with "-arch x86_64"
-      replace_in_cflags(/-march=\S*/, "-Xarch_#{Hardware::CPU.arch_32_bit} \\0")
-    end
+    return if compiler == :clang
+    return unless Hardware.is_32_bit?
+    # Can't mix "-march" for a 32-bit CPU  with "-arch x86_64"
+    replace_in_cflags(/-march=\S*/, "-Xarch_#{Hardware::CPU.arch_32_bit} \\0")
   end
 
   def cxx11
@@ -192,15 +191,11 @@ module Stdenv
   end
 
   def libcxx
-    if compiler == :clang
-      append "CXX", "-stdlib=libc++"
-    end
+    append "CXX", "-stdlib=libc++" if compiler == :clang
   end
 
   def libstdcxx
-    if compiler == :clang
-      append "CXX", "-stdlib=libstdc++"
-    end
+    append "CXX", "-stdlib=libstdc++" if compiler == :clang
   end
 
   # @private
@@ -211,7 +206,7 @@ module Stdenv
   end
 
   # Convenience method to set all C compiler flags in one shot.
-  def set_cflags(val)
+  def define_cflags(val)
     CC_FLAG_VARS.each { |key| self[key] = val }
   end
 
@@ -228,7 +223,7 @@ module Stdenv
     append flags, xarch unless xarch.empty?
     append flags, map.fetch(effective_arch, default)
   end
-  alias_method :generic_set_cpu_flags, :set_cpu_flags
+  alias generic_set_cpu_flags set_cpu_flags
 
   # @private
   def effective_arch
diff --git a/Library/Homebrew/extend/ENV/super.rb b/Library/Homebrew/extend/ENV/super.rb
index 4169905df..a3837c695 100644
--- a/Library/Homebrew/extend/ENV/super.rb
+++ b/Library/Homebrew/extend/ENV/super.rb
@@ -18,7 +18,7 @@ module Superenv
   attr_accessor :keg_only_deps, :deps
 
   attr_accessor :x11
-  alias_method :x11?, :x11
+  alias x11? x11
 
   def self.extended(base)
     base.keg_only_deps = []
@@ -64,9 +64,7 @@ module Superenv
     self["HOMEBREW_INCLUDE_PATHS"] = determine_include_paths
     self["HOMEBREW_LIBRARY_PATHS"] = determine_library_paths
     self["HOMEBREW_DEPENDENCIES"] = determine_dependencies
-    unless formula.nil?
-      self["HOMEBREW_FORMULA_PREFIX"] = formula.prefix
-    end
+    self["HOMEBREW_FORMULA_PREFIX"] = formula.prefix unless formula.nil?
 
     # The HOMEBREW_CCCFG ENV variable is used by the ENV/cc tool to control
     # compiler flag stripping. It consists of a string of characters which act
@@ -84,7 +82,7 @@ module Superenv
     # s - apply fix for sed's Unicode support
     # a - apply fix for apr-1-config path
   end
-  alias_method :generic_setup_build_environment, :setup_build_environment
+  alias generic_setup_build_environment setup_build_environment
 
   private
 
@@ -265,7 +263,7 @@ module Superenv
 
     old
   end
-  alias_method :j1, :deparallelize
+  alias j1 deparallelize
 
   def make_jobs
     self["MAKEFLAGS"] =~ /-\w*j(\d+)/
@@ -278,12 +276,12 @@ module Superenv
     self["HOMEBREW_ARCHFLAGS"] = Hardware::CPU.universal_archs.as_arch_flags
 
     # GCC doesn't accept "-march" for a 32-bit CPU with "-arch x86_64"
-    if compiler != :clang && Hardware::CPU.is_32_bit?
-      self["HOMEBREW_OPTFLAGS"] = self["HOMEBREW_OPTFLAGS"].sub(
-        /-march=\S*/,
-        "-Xarch_#{Hardware::CPU.arch_32_bit} \\0"
-      )
-    end
+    return if compiler == :clang
+    return unless Hardware::CPU.is_32_bit?
+    self["HOMEBREW_OPTFLAGS"] = self["HOMEBREW_OPTFLAGS"].sub(
+      /-march=\S*/,
+      "-Xarch_#{Hardware::CPU.arch_32_bit} \\0"
+    )
   end
 
   def permit_arch_flags
@@ -336,18 +334,18 @@ module Superenv
 
   # These methods are no longer necessary under superenv, but are needed to
   # maintain an interface compatible with stdenv.
-  alias_method :fast, :noop
-  alias_method :O4, :noop
-  alias_method :Og, :noop
-  alias_method :libxml2, :noop
-  alias_method :set_cpu_flags, :noop
+  alias fast noop
+  alias O4 noop
+  alias Og noop
+  alias libxml2 noop
+  alias set_cpu_flags noop
 
   # These methods provide functionality that has not yet been ported to
   # superenv.
-  alias_method :gcc_4_0_1, :noop
-  alias_method :minimal_optimization, :noop
-  alias_method :no_optimization, :noop
-  alias_method :enable_warnings, :noop
+  alias gcc_4_0_1 noop
+  alias minimal_optimization noop
+  alias no_optimization noop
+  alias enable_warnings noop
 end
 
 class Array
diff --git a/Library/Homebrew/extend/fileutils.rb b/Library/Homebrew/extend/fileutils.rb
index 3a2b32481..4f20d36a3 100644
--- a/Library/Homebrew/extend/fileutils.rb
+++ b/Library/Homebrew/extend/fileutils.rb
@@ -84,15 +84,14 @@ module FileUtils
   end
 
   # @private
-  alias_method :old_mkdir, :mkdir
+  alias old_mkdir mkdir
 
   # A version of mkdir that also changes to that folder in a block.
   def mkdir(name, &_block)
     mkdir_p(name)
-    if block_given?
-      chdir name do
-        yield
-      end
+    return unless block_given?
+    chdir name do
+      yield
     end
   end
   module_function :mkdir
@@ -122,7 +121,7 @@ module FileUtils
 
   if method_defined?(:ruby)
     # @private
-    alias_method :old_ruby, :ruby
+    alias old_ruby ruby
   end
 
   # Run the `ruby` Homebrew is using rather than whatever is in the `PATH`.
diff --git a/Library/Homebrew/extend/os/blacklist.rb b/Library/Homebrew/extend/os/blacklist.rb
index f72c7c643..932040f82 100644
--- a/Library/Homebrew/extend/os/blacklist.rb
+++ b/Library/Homebrew/extend/os/blacklist.rb
@@ -1,5 +1,2 @@
 require "blacklist"
-
-if OS.mac?
-  require "extend/os/mac/blacklist"
-end
+require "extend/os/mac/blacklist" if OS.mac?
diff --git a/Library/Homebrew/extend/os/bottles.rb b/Library/Homebrew/extend/os/bottles.rb
index aff9300de..146b807a4 100644
--- a/Library/Homebrew/extend/os/bottles.rb
+++ b/Library/Homebrew/extend/os/bottles.rb
@@ -1,5 +1,2 @@
 require "utils/bottles"
-
-if OS.mac?
-  require "extend/os/mac/utils/bottles"
-end
+require "extend/os/mac/utils/bottles" if OS.mac?
diff --git a/Library/Homebrew/extend/os/cleaner.rb b/Library/Homebrew/extend/os/cleaner.rb
index 868ff2d33..6b94cdf5a 100644
--- a/Library/Homebrew/extend/os/cleaner.rb
+++ b/Library/Homebrew/extend/os/cleaner.rb
@@ -1,5 +1,2 @@
 require "cleaner"
-
-if OS.mac?
-  require "extend/os/mac/cleaner"
-end
+require "extend/os/mac/cleaner" if OS.mac?
diff --git a/Library/Homebrew/extend/os/dependency_collector.rb b/Library/Homebrew/extend/os/dependency_collector.rb
new file mode 100644
index 000000000..56fcad31d
--- /dev/null
+++ b/Library/Homebrew/extend/os/dependency_collector.rb
@@ -0,0 +1,2 @@
+require "dependency_collector"
+require "extend/os/mac/dependency_collector" if OS.mac?
diff --git a/Library/Homebrew/extend/os/development_tools.rb b/Library/Homebrew/extend/os/development_tools.rb
index 7b590dc8b..5bd5cb81a 100644
--- a/Library/Homebrew/extend/os/development_tools.rb
+++ b/Library/Homebrew/extend/os/development_tools.rb
@@ -1,5 +1,2 @@
 require "development_tools"
-
-if OS.mac?
-  require "extend/os/mac/development_tools"
-end
+require "extend/os/mac/development_tools" if OS.mac?
diff --git a/Library/Homebrew/extend/os/diagnostic.rb b/Library/Homebrew/extend/os/diagnostic.rb
index 0c844743b..f8f53b1f4 100644
--- a/Library/Homebrew/extend/os/diagnostic.rb
+++ b/Library/Homebrew/extend/os/diagnostic.rb
@@ -1,5 +1,2 @@
 require "diagnostic"
-
-if OS.mac?
-  require "extend/os/mac/diagnostic"
-end
+require "extend/os/mac/diagnostic" if OS.mac?
diff --git a/Library/Homebrew/extend/os/emoji.rb b/Library/Homebrew/extend/os/emoji.rb
index fe3e7f44e..8fd99e1d3 100644
--- a/Library/Homebrew/extend/os/emoji.rb
+++ b/Library/Homebrew/extend/os/emoji.rb
@@ -1,6 +1,3 @@
 require "os"
 require "emoji"
-
-if OS.mac?
-  require "extend/os/mac/emoji"
-end
+require "extend/os/mac/emoji" if OS.mac?
diff --git a/Library/Homebrew/extend/os/extend/ENV/shared.rb b/Library/Homebrew/extend/os/extend/ENV/shared.rb
index 676159b37..e9574eb58 100644
--- a/Library/Homebrew/extend/os/extend/ENV/shared.rb
+++ b/Library/Homebrew/extend/os/extend/ENV/shared.rb
@@ -1,5 +1,2 @@
 require "extend/ENV/shared"
-
-if OS.mac?
-  require "extend/os/mac/extend/ENV/shared"
-end
+require "extend/os/mac/extend/ENV/shared" if OS.mac?
diff --git a/Library/Homebrew/extend/os/extend/ENV/std.rb b/Library/Homebrew/extend/os/extend/ENV/std.rb
index 320f9981f..8e6b13a61 100644
--- a/Library/Homebrew/extend/os/extend/ENV/std.rb
+++ b/Library/Homebrew/extend/os/extend/ENV/std.rb
@@ -1,5 +1,2 @@
 require "extend/ENV/std"
-
-if OS.mac?
-  require "extend/os/mac/extend/ENV/std"
-end
+require "extend/os/mac/extend/ENV/std" if OS.mac?
diff --git a/Library/Homebrew/extend/os/extend/ENV/super.rb b/Library/Homebrew/extend/os/extend/ENV/super.rb
index fd4e93c22..27c49eb84 100644
--- a/Library/Homebrew/extend/os/extend/ENV/super.rb
+++ b/Library/Homebrew/extend/os/extend/ENV/super.rb
@@ -1,5 +1,2 @@
 require "extend/ENV/super"
-
-if OS.mac?
-  require "extend/os/mac/extend/ENV/super"
-end
+require "extend/os/mac/extend/ENV/super" if OS.mac?
diff --git a/Library/Homebrew/extend/os/formula_cellar_checks.rb b/Library/Homebrew/extend/os/formula_cellar_checks.rb
index 4e30cd791..66b5b80d3 100644
--- a/Library/Homebrew/extend/os/formula_cellar_checks.rb
+++ b/Library/Homebrew/extend/os/formula_cellar_checks.rb
@@ -1,5 +1,2 @@
 require "formula_cellar_checks"
-
-if OS.mac?
-  require "extend/os/mac/formula_cellar_checks"
-end
+require "extend/os/mac/formula_cellar_checks" if OS.mac?
diff --git a/Library/Homebrew/extend/os/keg_relocate.rb b/Library/Homebrew/extend/os/keg_relocate.rb
index 2fde45d93..25a74286a 100644
--- a/Library/Homebrew/extend/os/keg_relocate.rb
+++ b/Library/Homebrew/extend/os/keg_relocate.rb
@@ -1,5 +1,2 @@
 require "keg_relocate"
-
-if OS.mac?
-  require "extend/os/mac/keg_relocate"
-end
+require "extend/os/mac/keg_relocate" if OS.mac?
diff --git a/Library/Homebrew/extend/os/linux/hardware/cpu.rb b/Library/Homebrew/extend/os/linux/hardware/cpu.rb
index 2e5b3d07d..2472c60ed 100644
--- a/Library/Homebrew/extend/os/linux/hardware/cpu.rb
+++ b/Library/Homebrew/extend/os/linux/hardware/cpu.rb
@@ -81,7 +81,7 @@ module Hardware
       %w[aes altivec avx avx2 lm sse3 ssse3 sse4 sse4_2].each do |flag|
         define_method(flag + "?") { flags.include? flag }
       end
-      alias_method :is_64_bit?, :lm?
+      alias is_64_bit? lm?
 
       def bits
         is_64_bit? ? 64 : 32
diff --git a/Library/Homebrew/extend/os/mac/dependency_collector.rb b/Library/Homebrew/extend/os/mac/dependency_collector.rb
new file mode 100644
index 000000000..ee98045b6
--- /dev/null
+++ b/Library/Homebrew/extend/os/mac/dependency_collector.rb
@@ -0,0 +1,6 @@
+class DependencyCollector
+  def ant_dep(spec, tags)
+    return if MacOS.version < :mavericks
+    Dependency.new(spec.to_s, tags)
+  end
+end
diff --git a/Library/Homebrew/extend/os/mac/development_tools.rb b/Library/Homebrew/extend/os/mac/development_tools.rb
index b9c9d8e43..381b26e66 100644
--- a/Library/Homebrew/extend/os/mac/development_tools.rb
+++ b/Library/Homebrew/extend/os/mac/development_tools.rb
@@ -3,7 +3,7 @@ require "os/mac/xcode"
 # @private
 class DevelopmentTools
   class << self
-    alias_method :original_locate, :locate
+    alias original_locate locate
     def locate(tool)
       (@locate ||= {}).fetch(tool) do |key|
         @locate[key] = if (located_tool = original_locate(tool))
diff --git a/Library/Homebrew/extend/os/mac/diagnostic.rb b/Library/Homebrew/extend/os/mac/diagnostic.rb
index 15dd3328f..063558f19 100644
--- a/Library/Homebrew/extend/os/mac/diagnostic.rb
+++ b/Library/Homebrew/extend/os/mac/diagnostic.rb
@@ -14,7 +14,7 @@ module Homebrew
       end
 
       def fatal_development_tools_checks
-        if MacOS.prerelease?
+        if MacOS.version >= :sierra && ENV["CI"].nil?
           %w[
             check_xcode_up_to_date
             check_clt_up_to_date
diff --git a/Library/Homebrew/extend/os/mac/extend/ENV/shared.rb b/Library/Homebrew/extend/os/mac/extend/ENV/shared.rb
index 866204024..67a3944c3 100644
--- a/Library/Homebrew/extend/os/mac/extend/ENV/shared.rb
+++ b/Library/Homebrew/extend/os/mac/extend/ENV/shared.rb
@@ -2,13 +2,8 @@ module SharedEnvExtension
   def no_weak_imports_support?
     return false unless compiler == :clang
 
-    if MacOS::Xcode.version && MacOS::Xcode.version < "8.0"
-      return false
-    end
-
-    if MacOS::CLT.version && MacOS::CLT.version < "8.0"
-      return false
-    end
+    return false if MacOS::Xcode.version && MacOS::Xcode.version < "8.0"
+    return false if MacOS::CLT.version && MacOS::CLT.version < "8.0"
 
     true
   end
diff --git a/Library/Homebrew/extend/os/mac/extend/ENV/std.rb b/Library/Homebrew/extend/os/mac/extend/ENV/std.rb
index 8efbd3bc9..4853ecf0c 100644
--- a/Library/Homebrew/extend/os/mac/extend/ENV/std.rb
+++ b/Library/Homebrew/extend/os/mac/extend/ENV/std.rb
@@ -20,14 +20,13 @@ module Stdenv
 
     # Leopard's ld needs some convincing that it's building 64-bit
     # See: https://github.com/mistydemeo/tigerbrew/issues/59
-    if MacOS.version == :leopard && MacOS.prefer_64_bit?
-      append "LDFLAGS", "-arch #{Hardware::CPU.arch_64_bit}"
+    return unless MacOS.version == :leopard && MacOS.prefer_64_bit?
+    append "LDFLAGS", "-arch #{Hardware::CPU.arch_64_bit}"
 
-      # Many, many builds are broken thanks to Leopard's buggy ld.
-      # Our ld64 fixes many of those builds, though of course we can't
-      # depend on it already being installed to build itself.
-      ld64 if Formula["ld64"].installed?
-    end
+    # Many, many builds are broken thanks to Leopard's buggy ld.
+    # Our ld64 fixes many of those builds, though of course we can't
+    # depend on it already being installed to build itself.
+    ld64 if Formula["ld64"].installed?
   end
 
   def homebrew_extra_pkg_config_paths
@@ -65,19 +64,18 @@ module Stdenv
     delete("CPATH")
     remove "LDFLAGS", "-L#{HOMEBREW_PREFIX}/lib"
 
-    if (sdk = MacOS.sdk_path(version)) && !MacOS::CLT.installed?
-      delete("SDKROOT")
-      remove_from_cflags "-isysroot #{sdk}"
-      remove "CPPFLAGS", "-isysroot #{sdk}"
-      remove "LDFLAGS", "-isysroot #{sdk}"
-      if HOMEBREW_PREFIX.to_s == "/usr/local"
-        delete("CMAKE_PREFIX_PATH")
-      else
-        # It was set in setup_build_environment, so we have to restore it here.
-        self["CMAKE_PREFIX_PATH"] = HOMEBREW_PREFIX.to_s
-      end
-      remove "CMAKE_FRAMEWORK_PATH", "#{sdk}/System/Library/Frameworks"
+    return unless (sdk = MacOS.sdk_path(version)) && !MacOS::CLT.installed?
+    delete("SDKROOT")
+    remove_from_cflags "-isysroot #{sdk}"
+    remove "CPPFLAGS", "-isysroot #{sdk}"
+    remove "LDFLAGS", "-isysroot #{sdk}"
+    if HOMEBREW_PREFIX.to_s == "/usr/local"
+      delete("CMAKE_PREFIX_PATH")
+    else
+      # It was set in setup_build_environment, so we have to restore it here.
+      self["CMAKE_PREFIX_PATH"] = HOMEBREW_PREFIX.to_s
     end
+    remove "CMAKE_FRAMEWORK_PATH", "#{sdk}/System/Library/Frameworks"
   end
 
   def macosxsdk(version = MacOS.version)
@@ -89,20 +87,19 @@ module Stdenv
     self["CPATH"] = "#{HOMEBREW_PREFIX}/include"
     prepend "LDFLAGS", "-L#{HOMEBREW_PREFIX}/lib"
 
-    if (sdk = MacOS.sdk_path(version)) && !MacOS::CLT.installed?
-      # Extra setup to support Xcode 4.3+ without CLT.
-      self["SDKROOT"] = sdk
-      # Tell clang/gcc where system include's are:
-      append_path "CPATH", "#{sdk}/usr/include"
-      # The -isysroot is needed, too, because of the Frameworks
-      append_to_cflags "-isysroot #{sdk}"
-      append "CPPFLAGS", "-isysroot #{sdk}"
-      # And the linker needs to find sdk/usr/lib
-      append "LDFLAGS", "-isysroot #{sdk}"
-      # Needed to build cmake itself and perhaps some cmake projects:
-      append_path "CMAKE_PREFIX_PATH", "#{sdk}/usr"
-      append_path "CMAKE_FRAMEWORK_PATH", "#{sdk}/System/Library/Frameworks"
-    end
+    return unless (sdk = MacOS.sdk_path(version)) && !MacOS::CLT.installed?
+    # Extra setup to support Xcode 4.3+ without CLT.
+    self["SDKROOT"] = sdk
+    # Tell clang/gcc where system include's are:
+    append_path "CPATH", "#{sdk}/usr/include"
+    # The -isysroot is needed, too, because of the Frameworks
+    append_to_cflags "-isysroot #{sdk}"
+    append "CPPFLAGS", "-isysroot #{sdk}"
+    # And the linker needs to find sdk/usr/lib
+    append "LDFLAGS", "-isysroot #{sdk}"
+    # Needed to build cmake itself and perhaps some cmake projects:
+    append_path "CMAKE_PREFIX_PATH", "#{sdk}/usr"
+    append_path "CMAKE_FRAMEWORK_PATH", "#{sdk}/System/Library/Frameworks"
   end
 
   # Some configure scripts won't find libxml2 without help
diff --git a/Library/Homebrew/extend/os/mac/extend/ENV/super.rb b/Library/Homebrew/extend/os/mac/extend/ENV/super.rb
index 78e36251c..38a81488f 100644
--- a/Library/Homebrew/extend/os/mac/extend/ENV/super.rb
+++ b/Library/Homebrew/extend/os/mac/extend/ENV/super.rb
@@ -118,6 +118,6 @@ module Superenv
 
   # These methods are no longer necessary under superenv, but are needed to
   # maintain an interface compatible with stdenv.
-  alias_method :macosxsdk, :noop
-  alias_method :remove_macosxsdk, :noop
+  alias macosxsdk noop
+  alias remove_macosxsdk noop
 end
diff --git a/Library/Homebrew/extend/os/mac/formula_cellar_checks.rb b/Library/Homebrew/extend/os/mac/formula_cellar_checks.rb
index b3f8250ee..8bc42ad35 100644
--- a/Library/Homebrew/extend/os/mac/formula_cellar_checks.rb
+++ b/Library/Homebrew/extend/os/mac/formula_cellar_checks.rb
@@ -64,13 +64,12 @@ module FormulaCellarChecks
     keg = Keg.new(formula.prefix)
     checker = LinkageChecker.new(keg, formula)
 
-    if checker.broken_dylibs?
-      audit_check_output <<-EOS.undent
-        The installation was broken.
-        Broken dylib links found:
-          #{checker.broken_dylibs.to_a * "\n          "}
-      EOS
-    end
+    return unless checker.broken_dylibs?
+    audit_check_output <<-EOS.undent
+      The installation was broken.
+      Broken dylib links found:
+        #{checker.broken_dylibs.to_a * "\n          "}
+    EOS
   end
 
   def audit_installed
diff --git a/Library/Homebrew/extend/os/mac/keg_relocate.rb b/Library/Homebrew/extend/os/mac/keg_relocate.rb
index 61d54ba97..33ee149ce 100644
--- a/Library/Homebrew/extend/os/mac/keg_relocate.rb
+++ b/Library/Homebrew/extend/os/mac/keg_relocate.rb
@@ -124,7 +124,7 @@ class Keg
   end
 
   def self.file_linked_libraries(file, string)
-    # Check dynamic library linkage. Importantly, do not run otool on static
+    # Check dynamic library linkage. Importantly, do not perform for static
     # libraries, which will falsely report "linkage" to themselves.
     if file.mach_o_executable? || file.dylib? || file.mach_o_bundle?
       file.dynamically_linked_libraries.select { |lib| lib.include? string }
diff --git a/Library/Homebrew/extend/os/mac/utils/bottles.rb b/Library/Homebrew/extend/os/mac/utils/bottles.rb
index 6b83ad6c4..0dd7341ea 100644
--- a/Library/Homebrew/extend/os/mac/utils/bottles.rb
+++ b/Library/Homebrew/extend/os/mac/utils/bottles.rb
@@ -21,7 +21,7 @@ module Utils
     class Collector
       private
 
-      alias_method :original_find_matching_tag, :find_matching_tag
+      alias original_find_matching_tag find_matching_tag
       def find_matching_tag(tag)
         original_find_matching_tag(tag) || find_altivec_tag(tag) || find_or_later_tag(tag)
       end
@@ -31,10 +31,9 @@ module Utils
       # sometimes a formula has just :tiger_altivec, other times it has
       # :tiger_g4, :tiger_g5, etc.
       def find_altivec_tag(tag)
-        if tag.to_s =~ /(\w+)_(g4|g4e|g5)$/
-          altivec_tag = "#{$1}_altivec".to_sym
-          altivec_tag if key?(altivec_tag)
-        end
+        return unless tag.to_s =~ /(\w+)_(g4|g4e|g5)$/
+        altivec_tag = "#{$1}_altivec".to_sym
+        altivec_tag if key?(altivec_tag)
       end
 
       # Allows a bottle tag to specify a specific OS or later,
diff --git a/Library/Homebrew/extend/os/system_config.rb b/Library/Homebrew/extend/os/system_config.rb
index cf7b69cb6..edc007166 100644
--- a/Library/Homebrew/extend/os/system_config.rb
+++ b/Library/Homebrew/extend/os/system_config.rb
@@ -1,5 +1,2 @@
 require "system_config"
-
-if OS.mac?
-  require "extend/os/mac/system_config"
-end
+require "extend/os/mac/system_config" if OS.mac?
diff --git a/Library/Homebrew/extend/pathname.rb b/Library/Homebrew/extend/pathname.rb
index 5dce906b9..3f73b6a1c 100644
--- a/Library/Homebrew/extend/pathname.rb
+++ b/Library/Homebrew/extend/pathname.rb
@@ -71,13 +71,13 @@ class Pathname
       when Array
         if src.empty?
           opoo "tried to install empty array to #{self}"
-          return
+          break
         end
         src.each { |s| install_p(s, File.basename(s)) }
       when Hash
         if src.empty?
           opoo "tried to install empty hash to #{self}"
-          return
+          break
         end
         src.each { |s, new_basename| install_p(s, new_basename) }
       else
@@ -132,7 +132,7 @@ class Pathname
 
   if method_defined?(:write)
     # @private
-    alias_method :old_write, :write
+    alias old_write write
   end
 
   # we assume this pathname object is a file obviously
@@ -212,7 +212,7 @@ class Pathname
   end
 
   # @private
-  alias_method :extname_old, :extname
+  alias extname_old extname
 
   # extended to support common double extensions
   def extname(path = to_s)
@@ -322,7 +322,7 @@ class Pathname
   end
 
   # FIXME: eliminate the places where we rely on this method
-  alias_method :to_str, :to_s unless method_defined?(:to_str)
+  alias to_str to_s unless method_defined?(:to_str)
 
   def cd
     Dir.chdir(self) { yield }
diff --git a/Library/Homebrew/extend/string.rb b/Library/Homebrew/extend/string.rb
index 1d9c2e036..162666d2d 100644
--- a/Library/Homebrew/extend/string.rb
+++ b/Library/Homebrew/extend/string.rb
@@ -13,7 +13,7 @@ class String
   #               sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt
   #               mollit anim id est laborum.
   #               EOS
-  alias_method :undent_________________________________________________________72, :undent
+  alias undent_________________________________________________________72 undent
 
   # String.chomp, but if result is empty: returns nil instead.
   # Allows `chuzzle || foo` short-circuits.
@@ -59,9 +59,8 @@ module StringInreplaceExtension
   # Looks for Makefile style variable defintions and replaces the
   # value with "new_value", or removes the definition entirely.
   def change_make_var!(flag, new_value)
-    unless gsub!(/^#{Regexp.escape(flag)}[ \t]*=[ \t]*(.*)$/, "#{flag}=#{new_value}", false)
-      errors << "expected to change #{flag.inspect} to #{new_value.inspect}"
-    end
+    return if gsub!(/^#{Regexp.escape(flag)}[ \t]*=[ \t]*(.*)$/, "#{flag}=#{new_value}", false)
+    errors << "expected to change #{flag.inspect} to #{new_value.inspect}"
   end
 
   # Removes variable assignments completely.
diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index 4cff28d8e..4d3c143dc 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -162,7 +162,7 @@ class Formula
   # Defaults to true.
   # @return [Boolean]
   attr_accessor :follow_installed_alias
-  alias_method :follow_installed_alias?, :follow_installed_alias
+  alias follow_installed_alias? follow_installed_alias
 
   # @private
   def initialize(name, path, spec, alias_path: nil)
@@ -179,12 +179,12 @@ class Formula
       Tap.fetch($1, $2)
     end
 
-    @full_name = get_full_name(name)
-    @full_alias_name = get_full_name(@alias_name)
+    @full_name = full_name_with_optional_tap(name)
+    @full_alias_name = full_name_with_optional_tap(@alias_name)
 
-    set_spec :stable
-    set_spec :devel
-    set_spec :head
+    spec_eval :stable
+    spec_eval :devel
+    spec_eval :head
 
     @active_spec = determine_active_spec(spec)
     @active_spec_sym = if head?
@@ -201,7 +201,7 @@ class Formula
   end
 
   # @private
-  def set_active_spec(spec_sym)
+  def active_spec=(spec_sym)
     spec = send(spec_sym)
     raise FormulaSpecificationError, "#{spec_sym} spec is not available for #{full_name}" unless spec
     @active_spec = spec
@@ -214,7 +214,7 @@ class Formula
 
   # Allow full name logic to be re-used between names, aliases,
   # and installed aliases.
-  def get_full_name(name)
+  def full_name_with_optional_tap(name)
     if name.nil? || @tap.nil? || @tap.core_tap?
       name
     else
@@ -222,12 +222,11 @@ class Formula
     end
   end
 
-  def set_spec(name)
+  def spec_eval(name)
     spec = self.class.send(name)
-    if spec.url
-      spec.owner = self
-      instance_variable_set("@#{name}", spec)
-    end
+    return unless spec.url
+    spec.owner = self
+    instance_variable_set("@#{name}", spec)
   end
 
   def determine_active_spec(requested)
@@ -246,9 +245,8 @@ class Formula
     end
 
     val = version.respond_to?(:to_str) ? version.to_str : version
-    if val.nil? || val.empty? || val =~ /\s/
-      raise FormulaValidationError.new(full_name, :version, val)
-    end
+    return unless val.nil? || val.empty? || val =~ /\s/
+    raise FormulaValidationError.new(full_name, :version, val)
   end
 
   public
@@ -266,7 +264,7 @@ class Formula
   end
 
   def full_installed_alias_name
-    get_full_name(installed_alias_name)
+    full_name_with_optional_tap(installed_alias_name)
   end
 
   # The path that was specified to find this formula.
@@ -395,9 +393,7 @@ class Formula
   def oldname
     @oldname ||= if tap
       formula_renames = tap.formula_renames
-      if formula_renames.value?(name)
-        formula_renames.to_a.rassoc(name).first
-      end
+      formula_renames.to_a.rassoc(name).first if formula_renames.value?(name)
     end
   end
 
@@ -1052,7 +1048,7 @@ class Formula
     self.class.link_overwrite_paths.any? do |p|
       p == to_check ||
         to_check.start_with?(p.chomp("/") + "/") ||
-        /^#{Regexp.escape(p).gsub('\*', ".*?")}$/ === to_check
+        to_check =~ /^#{Regexp.escape(p).gsub('\*', ".*?")}$/
     end
   end
 
@@ -1067,10 +1063,9 @@ class Formula
 
   # @private
   def patch
-    unless patchlist.empty?
-      ohai "Patching"
-      patchlist.each(&:apply)
-    end
+    return if patchlist.empty?
+    ohai "Patching"
+    patchlist.each(&:apply)
   end
 
   # yields |self,staging| with current working directory set to the uncompressed tarball
@@ -1096,10 +1091,11 @@ class Formula
   def lock
     @lock = FormulaLock.new(name)
     @lock.lock
-    if oldname && (oldname_rack = HOMEBREW_CELLAR/oldname).exist? && oldname_rack.resolved_path == rack
-      @oldname_lock = FormulaLock.new(oldname)
-      @oldname_lock.lock
-    end
+    return unless oldname
+    return unless (oldname_rack = HOMEBREW_CELLAR/oldname).exist?
+    return unless oldname_rack.resolved_path == rack
+    @oldname_lock = FormulaLock.new(oldname)
+    @oldname_lock.lock
   end
 
   # @private
@@ -1237,7 +1233,7 @@ class Formula
       name == other.name &&
       active_spec == other.active_spec
   end
-  alias_method :eql?, :==
+  alias eql? ==
 
   # @private
   def hash
@@ -1246,7 +1242,7 @@ class Formula
 
   # @private
   def <=>(other)
-    return unless Formula === other
+    return unless other.is_a?(Formula)
     name <=> other.name
   end
 
@@ -1266,7 +1262,7 @@ class Formula
   # Note: there isn't a std_autotools variant because autotools is a lot
   # less consistent and the standard parameters are more memorable.
   def std_cmake_args
-    %W[
+    args = %W[
       -DCMAKE_C_FLAGS_RELEASE=-DNDEBUG
       -DCMAKE_CXX_FLAGS_RELEASE=-DNDEBUG
       -DCMAKE_INSTALL_PREFIX=#{prefix}
@@ -1275,6 +1271,14 @@ class Formula
       -DCMAKE_VERBOSE_MAKEFILE=ON
       -Wno-dev
     ]
+
+    # Avoid false positives for clock_gettime support on 10.11.
+    # CMake cache entries for other weak symbols may be added here as needed.
+    if MacOS.version == "10.11" && MacOS::Xcode.installed? && MacOS::Xcode.version >= "8.0"
+      args << "-DHAVE_CLOCK_GETTIME:INTERNAL=0"
+    end
+
+    args
   end
 
   # an array of all core {Formula} names
@@ -1421,10 +1425,9 @@ class Formula
 
   # @private
   def print_tap_action(options = {})
-    if tap?
-      verb = options[:verb] || "Installing"
-      ohai "#{verb} #{name} from #{tap}"
-    end
+    return unless tap?
+    verb = options[:verb] || "Installing"
+    ohai "#{verb} #{name} from #{tap}"
   end
 
   # @private
@@ -1662,7 +1665,7 @@ class Formula
 
     @exec_count ||= 0
     @exec_count += 1
-    logfn = "#{logs}/#{active_log_prefix}%02d.%s" % [@exec_count, File.basename(cmd).split(" ").first]
+    logfn = format("#{logs}/#{active_log_prefix}%02d.%s", @exec_count, File.basename(cmd).split(" ").first)
     logs.mkpath
 
     File.open(logfn, "w") do |log|
@@ -1768,9 +1771,7 @@ class Formula
     ENV["HOMEBREW_CC_LOG_PATH"] = logfn
 
     # TODO: system "xcodebuild" is deprecated, this should be removed soon.
-    if cmd.to_s.start_with? "xcodebuild"
-      ENV.remove_cc_etc
-    end
+    ENV.remove_cc_etc if cmd.to_s.start_with? "xcodebuild"
 
     # Turn on argument filtering in the superenv compiler wrapper.
     # We should probably have a better mechanism for this than adding
@@ -1778,9 +1779,7 @@ class Formula
     if cmd == "python"
       setup_py_in_args = %w[setup.py build.py].include?(args.first)
       setuptools_shim_in_args = args.any? { |a| a.to_s.start_with? "import setuptools" }
-      if setup_py_in_args || setuptools_shim_in_args
-        ENV.refurbish_args
-      end
+      ENV.refurbish_args if setup_py_in_args || setuptools_shim_in_args
     end
 
     $stdout.reopen(out)
@@ -2218,7 +2217,7 @@ class Formula
     # If this formula conflicts with another one.
     # <pre>conflicts_with "imagemagick", :because => "because this is just a stupid example"</pre>
     def conflicts_with(*names)
-      opts = Hash === names.last ? names.pop : {}
+      opts = names.last.is_a?(Hash) ? names.pop : {}
       names.each { |name| conflicts << FormulaConflict.new(name, opts[:because]) }
     end
 
diff --git a/Library/Homebrew/formula_cellar_checks.rb b/Library/Homebrew/formula_cellar_checks.rb
index 3805d0f45..7db5e748b 100644
--- a/Library/Homebrew/formula_cellar_checks.rb
+++ b/Library/Homebrew/formula_cellar_checks.rb
@@ -1,7 +1,7 @@
 require "utils/shell"
 
 module FormulaCellarChecks
-  def check_PATH(bin)
+  def check_env_path(bin)
     # warn the user if stuff was installed outside of their PATH
     return unless bin.directory?
     return if bin.children.empty?
@@ -166,7 +166,7 @@ module FormulaCellarChecks
     audit_check_output(check_elisp_dirname(formula.share, formula.name))
     audit_check_output(check_elisp_root(formula.share, formula.name))
   end
-  alias_method :generic_audit_installed, :audit_installed
+  alias generic_audit_installed audit_installed
 
   private
 
diff --git a/Library/Homebrew/formula_installer.rb b/Library/Homebrew/formula_installer.rb
index f64b77026..3738c3784 100644
--- a/Library/Homebrew/formula_installer.rb
+++ b/Library/Homebrew/formula_installer.rb
@@ -24,7 +24,9 @@ class FormulaInstaller
     private(*names)
     names.each do |name|
       predicate = "#{name}?"
-      define_method(predicate) { !!send(name) }
+      define_method(predicate) do
+        send(name) ? true : false
+      end
       private(predicate)
     end
   end
@@ -71,7 +73,8 @@ class FormulaInstaller
   end
 
   def build_bottle?
-    !!@build_bottle && !formula.bottle_disabled?
+    return false unless @build_bottle
+    !formula.bottle_disabled?
   end
 
   def pour_bottle?(install_bottle_options = { warn: false })
@@ -130,12 +133,10 @@ class FormulaInstaller
     begin
       compute_dependencies
     rescue TapFormulaUnavailableError => e
-      if e.tap.installed?
-        raise
-      else
-        e.tap.install
-        retry
-      end
+      raise if e.tap.installed?
+
+      e.tap.install
+      retry
     end
   rescue FormulaUnavailableError => e
     e.dependent = formula.full_name
@@ -145,23 +146,24 @@ class FormulaInstaller
   def check_install_sanity
     raise FormulaInstallationAlreadyAttemptedError, formula if @@attempted.include?(formula)
 
-    unless skip_deps_check?
-      recursive_deps = formula.recursive_dependencies
-      unlinked_deps = recursive_deps.map(&:to_formula).select do |dep|
-        dep.installed? && !dep.keg_only? && !dep.linked_keg.directory?
-      end
-      raise CannotInstallFormulaError,
-        "You must `brew link #{unlinked_deps*" "}` before #{formula.full_name} can be installed" unless unlinked_deps.empty?
+    return if skip_deps_check?
 
-      pinned_unsatisfied_deps = recursive_deps.select do |dep|
-        dep.to_formula.pinned? && !dep.satisfied?(inherited_options_for(dep))
-      end
+    recursive_deps = formula.recursive_dependencies
+    unlinked_deps = recursive_deps.map(&:to_formula).select do |dep|
+      dep.installed? && !dep.keg_only? && !dep.linked_keg.directory?
+    end
 
-      unless pinned_unsatisfied_deps.empty?
-        raise CannotInstallFormulaError,
-          "You must `brew unpin #{pinned_unsatisfied_deps*" "}` as installing #{formula.full_name} requires the latest version of pinned dependencies"
-      end
+    unless unlinked_deps.empty?
+      raise CannotInstallFormulaError, "You must `brew link #{unlinked_deps*" "}` before #{formula.full_name} can be installed"
+    end
+
+    pinned_unsatisfied_deps = recursive_deps.select do |dep|
+      dep.to_formula.pinned? && !dep.satisfied?(inherited_options_for(dep))
     end
+
+    return if pinned_unsatisfied_deps.empty?
+    raise CannotInstallFormulaError,
+      "You must `brew unpin #{pinned_unsatisfied_deps*" "}` as installing #{formula.full_name} requires the latest version of pinned dependencies"
   end
 
   def build_bottle_preinstall
@@ -254,9 +256,7 @@ class FormulaInstaller
 
     unless @poured_bottle
       not_pouring = !pour_bottle || @pour_failed
-      if not_pouring && !ignore_deps?
-        compute_and_install_dependencies
-      end
+      compute_and_install_dependencies if not_pouring && !ignore_deps?
       build
       clean
     end
@@ -284,11 +284,10 @@ class FormulaInstaller
           #{formula}: #{e.message}
           'conflicts_with \"#{c.name}\"' should be removed from #{formula.path.basename}.
         EOS
-        if ARGV.homebrew_developer?
-          raise
-        else
-          $stderr.puts "Please report this to the #{formula.tap} tap!"
-        end
+
+        raise if ARGV.homebrew_developer?
+
+        $stderr.puts "Please report this to the #{formula.tap} tap!"
         false
       else
         f.linked_keg.exist? && f.opt_prefix.exist?
@@ -491,10 +490,9 @@ class FormulaInstaller
 
     c = Caveats.new(formula)
 
-    unless c.empty?
-      @show_summary_heading = true
-      ohai "Caveats", c.caveats
-    end
+    return if c.empty?
+    @show_summary_heading = true
+    ohai "Caveats", c.caveats
   end
 
   def finish
@@ -543,7 +541,7 @@ class FormulaInstaller
     @build_time ||= Time.now - @start_time if @start_time && !interactive?
   end
 
-  def sanitized_ARGV_options
+  def sanitized_argv_options
     args = []
     args << "--ignore-dependencies" if ignore_deps?
 
@@ -582,7 +580,7 @@ class FormulaInstaller
   end
 
   def build_argv
-    sanitized_ARGV_options + options.as_flags
+    sanitized_argv_options + options.as_flags
   end
 
   def build
@@ -705,13 +703,12 @@ class FormulaInstaller
       raise
     end
 
-    unless link_overwrite_backup.empty?
-      opoo "These files were overwritten during `brew link` step:"
-      puts link_overwrite_backup.keys
-      puts
-      puts "They have been backed up in #{backup_dir}"
-      @show_summary_heading = true
-    end
+    return if link_overwrite_backup.empty?
+    opoo "These files were overwritten during `brew link` step:"
+    puts link_overwrite_backup.keys
+    puts
+    puts "They have been backed up in #{backup_dir}"
+    @show_summary_heading = true
   end
 
   def install_plist
@@ -803,15 +800,14 @@ class FormulaInstaller
   end
 
   def audit_check_output(output)
-    if output
-      opoo output
-      @show_summary_heading = true
-    end
+    return unless output
+    opoo output
+    @show_summary_heading = true
   end
 
   def audit_installed
-    audit_check_output(check_PATH(formula.bin))
-    audit_check_output(check_PATH(formula.sbin))
+    audit_check_output(check_env_path(formula.bin))
+    audit_check_output(check_env_path(formula.sbin))
     super
   end
 
@@ -822,22 +818,20 @@ class FormulaInstaller
   end
 
   def lock
-    if (@@locked ||= []).empty?
-      formula.recursive_dependencies.each do |dep|
-        @@locked << dep.to_formula
-      end unless ignore_deps?
-      @@locked.unshift(formula)
-      @@locked.uniq!
-      @@locked.each(&:lock)
-      @hold_locks = true
-    end
+    return unless (@@locked ||= []).empty?
+    formula.recursive_dependencies.each do |dep|
+      @@locked << dep.to_formula
+    end unless ignore_deps?
+    @@locked.unshift(formula)
+    @@locked.uniq!
+    @@locked.each(&:lock)
+    @hold_locks = true
   end
 
   def unlock
-    if hold_locks?
-      @@locked.each(&:unlock)
-      @@locked.clear
-      @hold_locks = false
-    end
+    return unless hold_locks?
+    @@locked.each(&:unlock)
+    @@locked.clear
+    @hold_locks = false
   end
 end
diff --git a/Library/Homebrew/formula_lock.rb b/Library/Homebrew/formula_lock.rb
index 1ce62b328..bf747fea2 100644
--- a/Library/Homebrew/formula_lock.rb
+++ b/Library/Homebrew/formula_lock.rb
@@ -8,18 +8,16 @@ class FormulaLock
   end
 
   def lock
-    HOMEBREW_LOCK_DIR.mkpath
-    @lockfile = get_or_create_lockfile
-    unless @lockfile.flock(File::LOCK_EX | File::LOCK_NB)
-      raise OperationInProgressError, @name
-    end
+    @path.parent.mkpath
+    create_lockfile
+    return if @lockfile.flock(File::LOCK_EX | File::LOCK_NB)
+    raise OperationInProgressError, @name
   end
 
   def unlock
-    unless @lockfile.nil? || @lockfile.closed?
-      @lockfile.flock(File::LOCK_UN)
-      @lockfile.close
-    end
+    return if @lockfile.nil? || @lockfile.closed?
+    @lockfile.flock(File::LOCK_UN)
+    @lockfile.close
   end
 
   def with_lock
@@ -31,13 +29,9 @@ class FormulaLock
 
   private
 
-  def get_or_create_lockfile
-    if @lockfile.nil? || @lockfile.closed?
-      @lockfile = @path.open(File::RDWR | File::CREAT)
-      @lockfile.fcntl(Fcntl::F_SETFD, Fcntl::FD_CLOEXEC)
-      @lockfile
-    else
-      @lockfile
-    end
+  def create_lockfile
+    return unless @lockfile.nil? || @lockfile.closed?
+    @lockfile = @path.open(File::RDWR | File::CREAT)
+    @lockfile.fcntl(Fcntl::F_SETFD, Fcntl::FD_CLOEXEC)
   end
 end
diff --git a/Library/Homebrew/formula_versions.rb b/Library/Homebrew/formula_versions.rb
index ec2e2a459..81e15d314 100644
--- a/Library/Homebrew/formula_versions.rb
+++ b/Library/Homebrew/formula_versions.rb
@@ -52,9 +52,7 @@ class FormulaVersions
     rev_list(branch) do |rev|
       formula_at_revision(rev) do |f|
         bottle = f.bottle_specification
-        unless bottle.checksums.empty?
-          map[f.pkg_version] << bottle.rebuild
-        end
+        map[f.pkg_version] << bottle.rebuild unless bottle.checksums.empty?
       end
     end
     map
diff --git a/Library/Homebrew/formulary.rb b/Library/Homebrew/formulary.rb
index 74f669413..5ce09f6ba 100644
--- a/Library/Homebrew/formulary.rb
+++ b/Library/Homebrew/formulary.rb
@@ -37,18 +37,18 @@ class Formulary
   end
 
   def self.load_formula_from_path(name, path)
-    contents = path.open("r") { |f| set_encoding(f).read }
+    contents = path.open("r") { |f| ensure_utf8_encoding(f).read }
     namespace = "FormulaNamespace#{Digest::MD5.hexdigest(path.to_s)}"
     klass = load_formula(name, path, contents, namespace)
     FORMULAE[path] = klass
   end
 
   if IO.method_defined?(:set_encoding)
-    def self.set_encoding(io)
+    def self.ensure_utf8_encoding(io)
       io.set_encoding(Encoding::UTF_8)
     end
   else
-    def self.set_encoding(io)
+    def self.ensure_utf8_encoding(io)
       io
     end
   end
@@ -301,9 +301,7 @@ class Formulary
       return TapLoader.new(ref)
     end
 
-    if File.extname(ref) == ".rb"
-      return FromPathLoader.new(ref)
-    end
+    return FromPathLoader.new(ref) if File.extname(ref) == ".rb"
 
     formula_with_that_name = core_path(ref)
     if formula_with_that_name.file?
@@ -311,14 +309,14 @@ class Formulary
     end
 
     possible_alias = CoreTap.instance.alias_dir/ref
-    if possible_alias.file?
-      return AliasLoader.new(possible_alias)
-    end
+    return AliasLoader.new(possible_alias) if possible_alias.file?
 
     possible_tap_formulae = tap_paths(ref)
     if possible_tap_formulae.size > 1
       raise TapFormulaAmbiguityError.new(ref, possible_tap_formulae)
-    elsif possible_tap_formulae.size == 1
+    end
+
+    if possible_tap_formulae.size == 1
       path = possible_tap_formulae.first.resolved_path
       name = path.basename(".rb").to_s
       return FormulaLoader.new(name, path)
@@ -340,7 +338,9 @@ class Formulary
 
     if possible_tap_newname_formulae.size > 1
       raise TapFormulaWithOldnameAmbiguityError.new(ref, possible_tap_newname_formulae)
-    elsif !possible_tap_newname_formulae.empty?
+    end
+
+    unless possible_tap_newname_formulae.empty?
       return TapLoader.new(possible_tap_newname_formulae.first)
     end
 
@@ -372,7 +372,9 @@ class Formulary
     possible_pinned_tap_formulae = tap_paths(ref, Dir["#{HOMEBREW_LIBRARY}/PinnedTaps/*/*/"]).map(&:realpath)
     if possible_pinned_tap_formulae.size > 1
       raise TapFormulaAmbiguityError.new(ref, possible_pinned_tap_formulae)
-    elsif possible_pinned_tap_formulae.size == 1
+    end
+
+    if possible_pinned_tap_formulae.size == 1
       selected_formula = factory(possible_pinned_tap_formulae.first, spec)
       if core_path(ref).file?
         opoo <<-EOS.undent
diff --git a/Library/Homebrew/global.rb b/Library/Homebrew/global.rb
index 91692c146..0cd0d57e6 100644
--- a/Library/Homebrew/global.rb
+++ b/Library/Homebrew/global.rb
@@ -43,10 +43,10 @@ module Homebrew
   extend self
 
   attr_accessor :failed
-  alias_method :failed?, :failed
+  alias failed? failed
 
   attr_accessor :raise_deprecation_exceptions
-  alias_method :raise_deprecation_exceptions?, :raise_deprecation_exceptions
+  alias raise_deprecation_exceptions? raise_deprecation_exceptions
 end
 
 HOMEBREW_PULL_API_REGEX = %r{https://api\.github\.com/repos/([\w-]+)/([\w-]+)?/pulls/(\d+)}
diff --git a/Library/Homebrew/keg.rb b/Library/Homebrew/keg.rb
index ecbc4c6e0..d2c9e12e8 100644
--- a/Library/Homebrew/keg.rb
+++ b/Library/Homebrew/keg.rb
@@ -62,12 +62,17 @@ class Keg
   end
 
   # locale-specific directories have the form language[_territory][.codeset][@modifier]
-  LOCALEDIR_RX = /(locale|man)\/([a-z]{2}|C|POSIX)(_[A-Z]{2})?(\.[a-zA-Z\-0-9]+(@.+)?)?/
+  LOCALEDIR_RX = %r{(locale|man)/([a-z]{2}|C|POSIX)(_[A-Z]{2})?(\.[a-zA-Z\-0-9]+(@.+)?)?}
   INFOFILE_RX = %r{info/([^.].*?\.info|dir)$}
   TOP_LEVEL_DIRECTORIES = %w[bin etc include lib sbin share var Frameworks].freeze
   ALL_TOP_LEVEL_DIRECTORIES = (TOP_LEVEL_DIRECTORIES + %w[lib/pkgconfig share/locale share/man opt]).freeze
-  PRUNEABLE_DIRECTORIES = %w[bin etc include lib sbin share Frameworks LinkedKegs var/homebrew/linked].map do |d|
-    case d when "LinkedKegs" then HOMEBREW_LIBRARY/d else HOMEBREW_PREFIX/d end
+  PRUNEABLE_DIRECTORIES = %w[bin etc include lib sbin share Frameworks LinkedKegs var/homebrew/linked].map do |dir|
+    case dir
+    when "LinkedKegs"
+      HOMEBREW_LIBRARY/dir
+    else
+      HOMEBREW_PREFIX/dir
+    end
   end
 
   # These paths relative to the keg's share directory should always be real
@@ -113,9 +118,9 @@ class Keg
   end
 
   if Pathname.method_defined?(:to_path)
-    alias_method :to_path, :to_s
+    alias to_path to_s
   else
-    alias_method :to_str, :to_s
+    alias to_str to_s
   end
 
   def inspect
@@ -125,7 +130,7 @@ class Keg
   def ==(other)
     instance_of?(other.class) && path == other.path
   end
-  alias_method :eql?, :==
+  alias eql? ==
 
   def hash
     path.hash
@@ -249,10 +254,10 @@ class Keg
 
   def completion_installed?(shell)
     dir = case shell
-          when :bash then path.join("etc", "bash_completion.d")
-          when :zsh  then path.join("share", "zsh", "site-functions")
-          when :fish then path.join("share", "fish", "vendor_completions.d")
-          end
+    when :bash then path.join("etc", "bash_completion.d")
+    when :zsh  then path.join("share", "zsh", "site-functions")
+    when :fish then path.join("share", "fish", "vendor_completions.d")
+    end
     dir && dir.directory? && !dir.children.empty?
   end
 
@@ -318,13 +323,13 @@ class Keg
       when "locale/locale.alias" then :skip_file
       when INFOFILE_RX then :info
       when LOCALEDIR_RX then :mkpath
-      when /^icons\/.*\/icon-theme\.cache$/ then :skip_file
+      when %r{^icons/.*/icon-theme\.cache$} then :skip_file
       # all icons subfolders should also mkpath
-      when /^icons\// then :mkpath
+      when %r{^icons/} then :mkpath
       when /^zsh/ then :mkpath
       when /^fish/ then :mkpath
       # Lua, Lua51, Lua53 all need the same handling.
-      when /^lua\// then :mkpath
+      when %r{^lua/} then :mkpath
       when %r{^guile/} then :mkpath
       when *SHARE_PATHS then :mkpath
       else :link
@@ -362,7 +367,7 @@ class Keg
       # the :link strategy. However, for Foo.framework and
       # Foo.framework/Versions we have to use :mkpath so that multiple formulae
       # can link their versions into it and `brew [un]link` works.
-      if relative_path.to_s =~ /[^\/]*\.framework(\/Versions)?$/
+      if relative_path.to_s =~ %r{[^/]*\.framework(/Versions)?$}
         :mkpath
       else
         :link
@@ -389,10 +394,9 @@ class Keg
     opt_record.delete if opt_record.symlink? || opt_record.exist?
     make_relative_symlink(opt_record, path, mode)
 
-    if oldname_opt_record
-      oldname_opt_record.delete
-      make_relative_symlink(oldname_opt_record, path, mode)
-    end
+    return unless oldname_opt_record
+    oldname_opt_record.delete
+    make_relative_symlink(oldname_opt_record, path, mode)
   end
 
   def delete_pyc_files!
@@ -418,18 +422,19 @@ class Keg
       return
     end
 
-    if stat.directory?
-      begin
-        keg = Keg.for(src)
-      rescue NotAKegError
-        puts "Won't resolve conflicts for symlink #{dst} as it doesn't resolve into the Cellar" if ARGV.verbose?
-        return
+    return unless stat.directory?
+    begin
+      keg = Keg.for(src)
+    rescue NotAKegError
+      if ARGV.verbose?
+        puts "Won't resolve conflicts for symlink #{dst} as it doesn't resolve into the Cellar"
       end
-
-      dst.unlink unless mode.dry_run
-      keg.link_dir(src, mode) { :mkpath }
-      return true
+      return
     end
+
+    dst.unlink unless mode.dry_run
+    keg.link_dir(src, mode) { :mkpath }
+    true
   end
 
   def make_relative_symlink(dst, src, mode)
@@ -457,9 +462,8 @@ class Keg
     dst.delete if mode.overwrite && (dst.exist? || dst.symlink?)
     dst.make_relative_symlink(src)
   rescue Errno::EEXIST => e
-    if dst.exist?
-      raise ConflictError.new(self, src.relative_path_from(path), dst, e)
-    elsif dst.symlink?
+    raise ConflictError.new(self, src.relative_path_from(path), dst, e) if dst.exist?
+    if dst.symlink?
       dst.unlink
       retry
     end
diff --git a/Library/Homebrew/keg_relocate.rb b/Library/Homebrew/keg_relocate.rb
index 04f589984..3f0f4c8ed 100644
--- a/Library/Homebrew/keg_relocate.rb
+++ b/Library/Homebrew/keg_relocate.rb
@@ -13,7 +13,7 @@ class Keg
       end
     end
   end
-  alias_method :generic_fix_dynamic_linkage, :fix_dynamic_linkage
+  alias generic_fix_dynamic_linkage fix_dynamic_linkage
 
   def relocate_dynamic_linkage(_old_prefix, _new_prefix, _old_cellar, _new_cellar)
     []
diff --git a/Library/Homebrew/language/haskell.rb b/Library/Homebrew/language/haskell.rb
index b5d0e1220..4b7f88a99 100644
--- a/Library/Homebrew/language/haskell.rb
+++ b/Library/Homebrew/language/haskell.rb
@@ -79,19 +79,16 @@ module Language
 
           # if we have build flags, we have to pass them to cabal install to resolve the necessary
           # dependencies, and call cabal configure afterwards to set the flags again for compile
-          flags = ""
-          if options[:flags]
-            flags = "--flags=#{options[:flags].join(" ")}"
-          end
+          flags = "--flags=#{options[:flags].join(" ")}" if options[:flags]
 
           args_and_flags = args
-          args_and_flags << flags unless flags.empty?
+          args_and_flags << flags unless flags.nil?
 
           # install dependencies in the sandbox
           cabal_install "--only-dependencies", *args_and_flags
 
           # call configure if build flags are set
-          cabal_configure flags unless flags.empty?
+          cabal_configure flags unless flags.nil?
 
           # install the main package in the destination dir
           cabal_install "--prefix=#{prefix}", *args
diff --git a/Library/Homebrew/manpages/brew-cask.1.md b/Library/Homebrew/manpages/brew-cask.1.md
index fc14d54d1..4e160b527 100644
--- a/Library/Homebrew/manpages/brew-cask.1.md
+++ b/Library/Homebrew/manpages/brew-cask.1.md
@@ -19,10 +19,10 @@ names, and other aspects of this manual are still subject to change.
 
 ## FREQUENTLY USED COMMANDS
 
-  * `install [--force] [--skip-cask-deps] [--require-sha]` <token> [ <token> ... ]:
+  * `install` [--force] [--skip-cask-deps] [--require-sha] <token> [ <token> ... ]:
     Install Cask identified by <token>.
 
-  * `uninstall [--force]` <token> [ <token> ... ]:
+  * `uninstall` [--force] <token> [ <token> ... ]:
     Uninstall Cask identified by <token>.
 
   * `search` <text> | /<regexp>/:
@@ -69,7 +69,7 @@ names, and other aspects of this manual are still subject to change.
   * `info` or `abv` <token> [ <token> ... ]:
     Display information about the given Cask.
 
-  * `install [--force] [--skip-cask-deps] [--require-sha]` <token> [ <token> ... ]:
+  * `install` [--force] [--skip-cask-deps] [--require-sha] <token> [ <token> ... ]:
     Install the given Cask. With `--force`, re-install even if the Cask
     appears to be already present. With `--skip-cask-deps`, skip any Cask
     dependencies. `--require-sha` will abort installation if the Cask does not
@@ -78,42 +78,29 @@ names, and other aspects of this manual are still subject to change.
     <token> is usually the ID of a Cask as returned by `brew cask search`,
     but see [OTHER WAYS TO SPECIFY A CASK][] for variations.
 
-  * `list` or `ls` [-1 | -l] [ <token> ... ]:
+  * `list` or `ls` [-1] [--versions] [ <token> ... ]:
     Without any arguments, list all installed Casks. With `-1`, always
-    format the output in a single column. With `-l`, give a more detailed
-    listing.
+    format the output in a single column. With `--versions`, show all installed
+    versions.
 
     If <token> is given, summarize the staged files associated with the
     given Cask.
 
-  * `search` or `-S`:
-    Display all Casks available for install.
-
-  * `search` or `-S` <text> | /<regexp>/:
-    Perform a substring search of known Cask tokens for <text>. If the text
-    is delimited by slashes, it is interpreted as a Ruby regular expression.
+  * `search` or `-S` [<text> | /<regexp>/]:
+    Without argument, display all Casks available for install, otherwise
+    perform a substring search of known Cask tokens for <text> or, if the
+    text is delimited by slashes (/<regexp>/), it is interpreted as a
+    Ruby regular expression.
 
   * `style` [--fix] [ <token> ... ]:
    Check the given Casks for correct style using [RuboCop Cask](https://github.com/caskroom/rubocop-cask).
    If no tokens are given on the command line, all Casks are checked.
    With `--fix`, auto-correct any style errors if possible.
 
-  * `uninstall [--force]` or `rm` or `remove` <token> [ <token> ... ]:
+  * `uninstall` or `rm` or `remove` [--force] <token> [ <token> ... ]:
     Uninstall the given Cask. With `--force`, uninstall even if the Cask
     does not appear to be present.
 
-    Note that `uninstall --force` is currently imperfect. It will follow
-    the `uninstall` instructions from *newest* Cask definition, even if
-    the given Cask has changed since you installed it. The result is that
-    `uninstall --force` will always succeed in removing relevant files
-    under `<Caskroom_path>`, but will sometimes fail to remove relevant
-    installed files outside of it. This issue is being
-    addressed.
-
-    `uninstall` without `--force` is also imperfect. It may be unable to
-    perform an `uninstall` operation if the given Cask has changed since you
-    installed it. This issue is being addressed.
-
   * `update`:
     For convenience. `brew cask update` is a synonym for `brew update`.
 
diff --git a/Library/Homebrew/manpages/brew.1.md.erb b/Library/Homebrew/manpages/brew.1.md.erb
index e44dc2658..bc2140b40 100644
--- a/Library/Homebrew/manpages/brew.1.md.erb
+++ b/Library/Homebrew/manpages/brew.1.md.erb
@@ -255,11 +255,11 @@ Homebrew Documentation: <https://github.com/Homebrew/brew/blob/master/docs/>
 
 ## AUTHORS
 
-Homebrew's lead maintainer is <%= lead_maintainer %>.
+<%= lead_maintainer.concat("\n") %>
 
-Homebrew's current maintainers are <%= maintainers[0...-1].join(", ") %> and <%= maintainers[-1] %>.
+<%= maintainers.concat("\n") %>
 
-Former maintainers with significant contributions include <%= former_maintainers.join(", ") %> and Homebrew's creator: <%= creator %>.
+<%= former_maintainers.concat("\n") %>
 
 ## BUGS
 
diff --git a/Library/Homebrew/migrator.rb b/Library/Homebrew/migrator.rb
index d31025119..4f8cba1ce 100644
--- a/Library/Homebrew/migrator.rb
+++ b/Library/Homebrew/migrator.rb
@@ -101,7 +101,7 @@ class Migrator
 
     @new_cellar = HOMEBREW_CELLAR/formula.name
 
-    if @old_linked_keg = get_linked_old_linked_keg
+    if @old_linked_keg = linked_old_linked_keg
       @old_linked_keg_record = old_linked_keg.linked_keg_record if old_linked_keg.linked?
       @old_opt_record = old_linked_keg.opt_record if old_linked_keg.optlinked?
       @new_linked_keg_record = HOMEBREW_CELLAR/"#{newname}/#{File.basename(old_linked_keg)}"
@@ -137,7 +137,7 @@ class Migrator
     end
   end
 
-  def get_linked_old_linked_keg
+  def linked_old_linked_keg
     kegs = old_cellar.subdirs.map { |d| Keg.new(d) }
     kegs.detect(&:linked?) || kegs.detect(&:optlinked?)
   end
@@ -182,22 +182,21 @@ class Migrator
   end
 
   def repin
-    if pinned?
-      # old_pin_record is a relative symlink and when we try to to read it
-      # from <dir> we actually try to find file
-      # <dir>/../<...>/../Cellar/name/version.
-      # To repin formula we need to update the link thus that it points to
-      # the right directory.
-      # NOTE: old_pin_record.realpath.sub(oldname, newname) is unacceptable
-      # here, because it resolves every symlink for old_pin_record and then
-      # substitutes oldname with newname. It breaks things like
-      # Pathname#make_relative_symlink, where Pathname#relative_path_from
-      # is used to find relative path from source to destination parent and
-      # it assumes no symlinks.
-      src_oldname = old_pin_record.dirname.join(old_pin_link_record).expand_path
-      new_pin_record.make_relative_symlink(src_oldname.sub(oldname, newname))
-      old_pin_record.delete
-    end
+    return unless pinned?
+    # old_pin_record is a relative symlink and when we try to to read it
+    # from <dir> we actually try to find file
+    # <dir>/../<...>/../Cellar/name/version.
+    # To repin formula we need to update the link thus that it points to
+    # the right directory.
+    # NOTE: old_pin_record.realpath.sub(oldname, newname) is unacceptable
+    # here, because it resolves every symlink for old_pin_record and then
+    # substitutes oldname with newname. It breaks things like
+    # Pathname#make_relative_symlink, where Pathname#relative_path_from
+    # is used to find relative path from source to destination parent and
+    # it assumes no symlinks.
+    src_oldname = old_pin_record.dirname.join(old_pin_link_record).expand_path
+    new_pin_record.make_relative_symlink(src_oldname.sub(oldname, newname))
+    old_pin_record.delete
   end
 
   def unlink_oldname
@@ -254,10 +253,9 @@ class Migrator
 
   # Link keg to opt if it was linked before migrating.
   def link_oldname_opt
-    if old_opt_record
-      old_opt_record.delete if old_opt_record.symlink?
-      old_opt_record.make_relative_symlink(new_linked_keg_record)
-    end
+    return unless old_opt_record
+    old_opt_record.delete if old_opt_record.symlink?
+    old_opt_record.make_relative_symlink(new_linked_keg_record)
   end
 
   # After migtaion every INSTALL_RECEIPT.json has wrong path to the formula
@@ -316,30 +314,27 @@ class Migrator
       end
     end
 
-    unless old_linked_keg.nil?
-      # The keg used to be linked and when we backup everything we restore
-      # Cellar/oldname, the target also gets restored, so we are able to
-      # create a keg using its old path
-      if old_linked_keg_record
-        begin
-          old_linked_keg.link
-        rescue Keg::LinkError
-          old_linked_keg.unlink
-          raise
-        rescue Keg::AlreadyLinkedError
-          old_linked_keg.unlink
-          retry
-        end
-      else
-        old_linked_keg.optlink
+    return if old_linked_keg.nil?
+    # The keg used to be linked and when we backup everything we restore
+    # Cellar/oldname, the target also gets restored, so we are able to
+    # create a keg using its old path
+    if old_linked_keg_record
+      begin
+        old_linked_keg.link
+      rescue Keg::LinkError
+        old_linked_keg.unlink
+        raise
+      rescue Keg::AlreadyLinkedError
+        old_linked_keg.unlink
+        retry
       end
+    else
+      old_linked_keg.optlink
     end
   end
 
   def backup_oldname_cellar
-    unless old_cellar.exist?
-      FileUtils.mv(new_cellar, old_cellar)
-    end
+    FileUtils.mv(new_cellar, old_cellar) unless old_cellar.exist?
   end
 
   def backup_old_tabs
diff --git a/Library/Homebrew/official_taps.rb b/Library/Homebrew/official_taps.rb
index 53f3640d1..a220c9239 100644
--- a/Library/Homebrew/official_taps.rb
+++ b/Library/Homebrew/official_taps.rb
@@ -18,5 +18,6 @@ OFFICIAL_TAPS = %w[
 
 OFFICIAL_CMD_TAPS = {
   "homebrew/bundle" => ["bundle"],
+  "homebrew/test-bot" => ["test-bot"],
   "homebrew/services" => ["services"],
 }.freeze
diff --git a/Library/Homebrew/options.rb b/Library/Homebrew/options.rb
index 1d92fbf47..08f459b24 100644
--- a/Library/Homebrew/options.rb
+++ b/Library/Homebrew/options.rb
@@ -14,14 +14,14 @@ class Option
   end
 
   def <=>(other)
-    return unless Option === other
+    return unless other.is_a?(Option)
     name <=> other.name
   end
 
   def ==(other)
     instance_of?(other.class) && name == other.name
   end
-  alias_method :eql?, :==
+  alias eql? ==
 
   def hash
     name.hash
@@ -51,7 +51,7 @@ class DeprecatedOption
   def ==(other)
     instance_of?(other.class) && old == other.old && current == other.current
   end
-  alias_method :eql?, :==
+  alias eql? ==
 end
 
 class Options
@@ -106,7 +106,7 @@ class Options
     any? { |opt| opt == o || opt.name == o || opt.flag == o }
   end
 
-  alias_method :to_ary, :to_a
+  alias to_ary to_a
 
   def inspect
     "#<#{self.class.name}: #{to_a.inspect}>"
diff --git a/Library/Homebrew/os/mac.rb b/Library/Homebrew/os/mac.rb
index f121cbbd3..029c761f7 100644
--- a/Library/Homebrew/os/mac.rb
+++ b/Library/Homebrew/os/mac.rb
@@ -45,26 +45,6 @@ module OS
       @language ||= Utils.popen_read("defaults", "read", ".GlobalPreferences", "AppleLanguages").delete(" \n\"()").sub(/,.*/, "")
     end
 
-    # Locates a (working) copy of install_name_tool, guaranteed to function
-    # whether the user has developer tools installed or not.
-    def install_name_tool
-      if (path = HOMEBREW_PREFIX/"opt/cctools/bin/install_name_tool").executable?
-        path
-      else
-        DevelopmentTools.locate("install_name_tool")
-      end
-    end
-
-    # Locates a (working) copy of otool, guaranteed to function whether the user
-    # has developer tools installed or not.
-    def otool
-      if (path = HOMEBREW_PREFIX/"opt/cctools/bin/otool").executable?
-        path
-      else
-        DevelopmentTools.locate("otool")
-      end
-    end
-
     def active_developer_dir
       @active_developer_dir ||= Utils.popen_read("/usr/bin/xcode-select", "-print-path").strip
     end
diff --git a/Library/Homebrew/os/mac/cctools_keg.rb b/Library/Homebrew/os/mac/cctools_keg.rb
deleted file mode 100644
index cd928f522..000000000
--- a/Library/Homebrew/os/mac/cctools_keg.rb
+++ /dev/null
@@ -1,21 +0,0 @@
-module CctoolsKeg
-  def install_name_tool(*args)
-    @require_install_name_tool = true
-    tool = MacOS.install_name_tool
-    system(tool, *args) || raise(ErrorDuringExecution.new(tool, args))
-  end
-
-  def require_install_name_tool?
-    !!@require_install_name_tool
-  end
-
-  def change_dylib_id(id, file)
-    puts "Changing dylib ID of #{file}\n  from #{file.dylib_id}\n    to #{id}" if ARGV.debug?
-    install_name_tool("-id", id, file)
-  end
-
-  def change_install_name(old, new, file)
-    puts "Changing install name in #{file}\n  from #{old}\n    to #{new}" if ARGV.debug?
-    install_name_tool("-change", old, new, file)
-  end
-end
diff --git a/Library/Homebrew/os/mac/cctools_mach.rb b/Library/Homebrew/os/mac/cctools_mach.rb
deleted file mode 100644
index 7e8b96b83..000000000
--- a/Library/Homebrew/os/mac/cctools_mach.rb
+++ /dev/null
@@ -1,99 +0,0 @@
-module CctoolsMachO
-  # @private
-  OTOOL_RX = /\t(.*) \(compatibility version (?:\d+\.)*\d+, current version (?:\d+\.)*\d+\)/
-
-  # Mach-O binary methods, see:
-  # /usr/include/mach-o/loader.h
-  # /usr/include/mach-o/fat.h
-  # @private
-  def mach_data
-    @mach_data ||= begin
-      offsets = []
-      mach_data = []
-
-      header = read(8).unpack("N2")
-      case header[0]
-      when 0xcafebabe # universal
-        header[1].times do |i|
-          # header[1] is the number of struct fat_arch in the file.
-          # Each struct fat_arch is 20 bytes, and the 'offset' member
-          # begins 8 bytes into the struct, with an additional 8 byte
-          # offset due to the struct fat_header at the beginning of
-          # the file.
-          offsets << read(4, 20*i + 16).unpack("N")[0]
-        end
-      when 0xcefaedfe, 0xcffaedfe, 0xfeedface, 0xfeedfacf # Single arch
-        offsets << 0
-      else
-        raise "Not a Mach-O binary."
-      end
-
-      offsets.each do |offset|
-        arch = case read(8, offset).unpack("N2")
-          when [0xcefaedfe, 0x07000000] then :i386
-          when [0xcffaedfe, 0x07000001] then :x86_64
-          when [0xfeedface, 0x00000012] then :ppc7400
-          when [0xfeedfacf, 0x01000012] then :ppc64
-          else :dunno
-          end
-
-        type = case read(4, offset + 12).unpack("N")[0]
-          when 0x00000002, 0x02000000 then :executable
-          when 0x00000006, 0x06000000 then :dylib
-          when 0x00000008, 0x08000000 then :bundle
-          else :dunno
-          end
-
-        mach_data << { arch: arch, type: type }
-      end
-      mach_data
-    rescue
-      []
-    end
-  end
-
-  # @private
-  class Metadata
-    attr_reader :path, :dylib_id, :dylibs
-
-    def initialize(path)
-      @path = path
-      @dylib_id, @dylibs = parse_otool_L_output
-    end
-
-    def parse_otool_L_output
-      args = ["-L", path.expand_path.to_s]
-      libs = Utils.popen_read(OS::Mac.otool, *args).split("\n")
-      unless $?.success?
-        raise ErrorDuringExecution.new(OS::Mac.otool, args)
-      end
-
-      libs.shift # first line is the filename
-
-      id = libs.shift[OTOOL_RX, 1] if path.dylib?
-      libs.map! { |lib| lib[OTOOL_RX, 1] }.compact!
-
-      [id, libs]
-    end
-  end
-
-  # @private
-  def mach_metadata
-    @mach_metadata ||= Metadata.new(self)
-  end
-
-  # Returns an array containing all dynamically-linked libraries, based on the
-  # output of otool. This returns the install names, so these are not guaranteed
-  # to be absolute paths.
-  # Returns an empty array both for software that links against no libraries,
-  # and for non-mach objects.
-  # @private
-  def dynamically_linked_libraries
-    mach_metadata.dylibs
-  end
-
-  # @private
-  def dylib_id
-    mach_metadata.dylib_id
-  end
-end
diff --git a/Library/Homebrew/os/mac/keg.rb b/Library/Homebrew/os/mac/keg.rb
index 201c57b50..b2a769849 100644
--- a/Library/Homebrew/os/mac/keg.rb
+++ b/Library/Homebrew/os/mac/keg.rb
@@ -1,9 +1,31 @@
 class Keg
-  if !ENV["HOMEBREW_NO_RUBY_MACHO"]
-    require "os/mac/ruby_keg"
-    include RubyKeg
-  else
-    require "os/mac/cctools_keg"
-    include CctoolsKeg
+  def change_dylib_id(id, file)
+    @require_relocation = true
+    puts "Changing dylib ID of #{file}\n  from #{file.dylib_id}\n    to #{id}" if ARGV.debug?
+    MachO::Tools.change_dylib_id(file, id, strict: false)
+  rescue MachO::MachOError
+    onoe <<-EOS.undent
+      Failed changing dylib ID of #{file}
+        from #{file.dylib_id}
+          to #{id}
+    EOS
+    raise
+  end
+
+  def change_install_name(old, new, file)
+    @require_relocation = true
+    puts "Changing install name in #{file}\n  from #{old}\n    to #{new}" if ARGV.debug?
+    MachO::Tools.change_install_name(file, old, new, strict: false)
+  rescue MachO::MachOError
+    onoe <<-EOS.undent
+      Failed changing install name in #{file}
+        from #{old}
+          to #{new}
+    EOS
+    raise
+  end
+
+  def require_relocation?
+    @require_relocation
   end
 end
diff --git a/Library/Homebrew/os/mac/ruby_mach.rb b/Library/Homebrew/os/mac/mach.rb
index 5d0e75c31..07598a23d 100644
--- a/Library/Homebrew/os/mac/ruby_mach.rb
+++ b/Library/Homebrew/os/mac/mach.rb
@@ -1,6 +1,7 @@
 require "vendor/macho/macho"
+require "os/mac/architecture_list"
 
-module RubyMachO
+module MachO
   # @private
   def macho
     @macho ||= begin
@@ -57,4 +58,51 @@ module RubyMachO
   def dylib_id
     macho.dylib_id
   end
+
+  def archs
+    mach_data.map { |m| m.fetch :arch }.extend(ArchitectureListExtension)
+  end
+
+  def arch
+    case archs.length
+    when 0 then :dunno
+    when 1 then archs.first
+    else :universal
+    end
+  end
+
+  def universal?
+    arch == :universal
+  end
+
+  def i386?
+    arch == :i386
+  end
+
+  def x86_64?
+    arch == :x86_64
+  end
+
+  def ppc7400?
+    arch == :ppc7400
+  end
+
+  def ppc64?
+    arch == :ppc64
+  end
+
+  # @private
+  def dylib?
+    mach_data.any? { |m| m.fetch(:type) == :dylib }
+  end
+
+  # @private
+  def mach_o_executable?
+    mach_data.any? { |m| m.fetch(:type) == :executable }
+  end
+
+  # @private
+  def mach_o_bundle?
+    mach_data.any? { |m| m.fetch(:type) == :bundle }
+  end
 end
diff --git a/Library/Homebrew/os/mac/pathname.rb b/Library/Homebrew/os/mac/pathname.rb
index b76c4333a..9b65d7ac0 100644
--- a/Library/Homebrew/os/mac/pathname.rb
+++ b/Library/Homebrew/os/mac/pathname.rb
@@ -1,13 +1,5 @@
-require "os/mac/shared_mach"
+require "os/mac/mach"
 
 class Pathname
-  if !ENV["HOMEBREW_NO_RUBY_MACHO"]
-    require "os/mac/ruby_mach"
-    include RubyMachO
-  else
-    require "os/mac/cctools_mach"
-    include CctoolsMachO
-  end
-
-  include SharedMachO
+  include MachO
 end
diff --git a/Library/Homebrew/os/mac/ruby_keg.rb b/Library/Homebrew/os/mac/ruby_keg.rb
deleted file mode 100644
index e476b174f..000000000
--- a/Library/Homebrew/os/mac/ruby_keg.rb
+++ /dev/null
@@ -1,33 +0,0 @@
-require "vendor/macho/macho"
-
-module RubyKeg
-  def change_dylib_id(id, file)
-    @require_install_name_tool = true
-    puts "Changing dylib ID of #{file}\n  from #{file.dylib_id}\n    to #{id}" if ARGV.debug?
-    MachO::Tools.change_dylib_id(file, id, strict: false)
-  rescue MachO::MachOError
-    onoe <<-EOS.undent
-      Failed changing dylib ID of #{file}
-        from #{file.dylib_id}
-          to #{id}
-    EOS
-    raise
-  end
-
-  def change_install_name(old, new, file)
-    @require_install_name_tool = true
-    puts "Changing install name in #{file}\n  from #{old}\n    to #{new}" if ARGV.debug?
-    MachO::Tools.change_install_name(file, old, new, strict: false)
-  rescue MachO::MachOError
-    onoe <<-EOS.undent
-      Failed changing install name in #{file}
-        from #{old}
-          to #{new}
-    EOS
-    raise
-  end
-
-  def require_install_name_tool?
-    !!@require_install_name_tool
-  end
-end
diff --git a/Library/Homebrew/os/mac/shared_mach.rb b/Library/Homebrew/os/mac/shared_mach.rb
deleted file mode 100644
index aa8baa92e..000000000
--- a/Library/Homebrew/os/mac/shared_mach.rb
+++ /dev/null
@@ -1,50 +0,0 @@
-require "os/mac/architecture_list"
-
-module SharedMachO
-  def archs
-    mach_data.map { |m| m.fetch :arch }.extend(ArchitectureListExtension)
-  end
-
-  def arch
-    case archs.length
-    when 0 then :dunno
-    when 1 then archs.first
-    else :universal
-    end
-  end
-
-  def universal?
-    arch == :universal
-  end
-
-  def i386?
-    arch == :i386
-  end
-
-  def x86_64?
-    arch == :x86_64
-  end
-
-  def ppc7400?
-    arch == :ppc7400
-  end
-
-  def ppc64?
-    arch == :ppc64
-  end
-
-  # @private
-  def dylib?
-    mach_data.any? { |m| m.fetch(:type) == :dylib }
-  end
-
-  # @private
-  def mach_o_executable?
-    mach_data.any? { |m| m.fetch(:type) == :executable }
-  end
-
-  # @private
-  def mach_o_bundle?
-    mach_data.any? { |m| m.fetch(:type) == :bundle }
-  end
-end
diff --git a/Library/Homebrew/os/mac/xcode.rb b/Library/Homebrew/os/mac/xcode.rb
index f487a6997..0f78e4412 100644
--- a/Library/Homebrew/os/mac/xcode.rb
+++ b/Library/Homebrew/os/mac/xcode.rb
@@ -15,15 +15,13 @@ module OS
         when "10.8"  then "5.1.1"
         when "10.9"  then "6.2"
         when "10.10" then "7.2.1"
-        when "10.11" then "7.3.1"
+        when "10.11" then "8.0"
         when "10.12" then "8.0"
         else
+          raise "macOS '#{MacOS.version}' is invalid" unless OS::Mac.prerelease?
+
           # Default to newest known version of Xcode for unreleased macOS versions.
-          if OS::Mac.prerelease?
-            "8.0"
-          else
-            raise "macOS '#{MacOS.version}' is invalid"
-          end
+          "8.0"
         end
       end
 
@@ -175,7 +173,7 @@ module OS
       # Returns true even if outdated tools are installed, e.g.
       # tools from Xcode 4.x on 10.9
       def installed?
-        !!detect_version
+        !detect_version.nil?
       end
 
       def update_instructions
@@ -193,6 +191,9 @@ module OS
       end
 
       def latest_version
+        # As of Xcode 8 CLT releases are no longer in sync with Xcode releases
+        # on the older supported platform for that Xcode release, i.e there's no
+        # CLT package for 10.11 that contains the Clang version from Xcode 8.
         case MacOS.version
         when "10.12" then "800.0.38"
         when "10.11" then "703.0.31"
@@ -206,9 +207,9 @@ module OS
 
       def outdated?
         if MacOS.version >= :mavericks
-          version = `#{MAVERICKS_PKG_PATH}/usr/bin/clang --version`
+          version = Utils.popen_read("#{MAVERICKS_PKG_PATH}/usr/bin/clang --version")
         else
-          version = `/usr/bin/clang --version`
+          version = Utils.popen_read("/usr/bin/clang --version")
         end
         version = version[/clang-(\d+\.\d+\.\d+(\.\d+)?)/, 1] || "0"
         version < latest_version
diff --git a/Library/Homebrew/patch.rb b/Library/Homebrew/patch.rb
index 1148389cf..1b7751ba3 100644
--- a/Library/Homebrew/patch.rb
+++ b/Library/Homebrew/patch.rb
@@ -89,7 +89,7 @@ class DATAPatch < EmbeddedPatch
     path.open("rb") do |f|
       begin
         line = f.gets
-      end until line.nil? || /^__END__$/ === line
+      end until line.nil? || line =~ /^__END__$/
       data << line while line = f.gets
     end
     data
@@ -130,14 +130,13 @@ class ExternalPatch
       patch_dir = Pathname.pwd
       if patch_files.empty?
         children = patch_dir.children
-        if children.length == 1 && children.first.file?
-          patch_files << children.first.basename
-        else
+        if children.length != 1 || !children.first.file?
           raise MissingApplyError, <<-EOS.undent
             There should be exactly one patch file in the staging directory unless
             the "apply" method was used one or more times in the patch-do block.
           EOS
         end
+        patch_files << children.first.basename
       end
       dir.cd do
         patch_files.each do |patch_file|
diff --git a/Library/Homebrew/pkg_version.rb b/Library/Homebrew/pkg_version.rb
index 4bf701f35..761a349fd 100644
--- a/Library/Homebrew/pkg_version.rb
+++ b/Library/Homebrew/pkg_version.rb
@@ -29,13 +29,13 @@ class PkgVersion
       version.to_s
     end
   end
-  alias_method :to_str, :to_s
+  alias to_str to_s
 
   def <=>(other)
-    return unless PkgVersion === other
+    return unless other.is_a?(PkgVersion)
     (version <=> other.version).nonzero? || revision <=> other.revision
   end
-  alias_method :eql?, :==
+  alias eql? ==
 
   def hash
     version.hash ^ revision.hash
diff --git a/Library/Homebrew/readall.rb b/Library/Homebrew/readall.rb
index 61222e015..3dd7075ec 100644
--- a/Library/Homebrew/readall.rb
+++ b/Library/Homebrew/readall.rb
@@ -1,7 +1,6 @@
 require "formula"
 require "tap"
 require "thread"
-require "readall"
 
 module Readall
   class << self
diff --git a/Library/Homebrew/requirement.rb b/Library/Homebrew/requirement.rb
index 4ea15774d..89487fec3 100644
--- a/Library/Homebrew/requirement.rb
+++ b/Library/Homebrew/requirement.rb
@@ -56,7 +56,7 @@ class Requirement
   def satisfied?
     result = self.class.satisfy.yielder { |p| instance_eval(&p) }
     @satisfied_result = result
-    !!result
+    result ? true : false
   end
 
   # Overriding #fatal? is deprecated.
@@ -83,12 +83,11 @@ class Requirement
     # PATH.
     # This is undocumented magic and it should be removed, but we need to add
     # a way to declare path-based requirements that work with superenv first.
-    if Pathname === @satisfied_result
-      parent = @satisfied_result.parent
-      unless ENV["PATH"].split(File::PATH_SEPARATOR).include?(parent.to_s)
-        ENV.append_path("PATH", parent)
-      end
-    end
+    return unless @satisfied_result.is_a?(Pathname)
+    parent = @satisfied_result.parent
+
+    return if ENV["PATH"].split(File::PATH_SEPARATOR).include?(parent.to_s)
+    ENV.append_path("PATH", parent)
   end
 
   def env
@@ -102,7 +101,7 @@ class Requirement
   def ==(other)
     instance_of?(other.class) && name == other.name && tags == other.tags
   end
-  alias_method :eql?, :==
+  alias eql? ==
 
   def hash
     name.hash ^ tags.hash
@@ -115,7 +114,7 @@ class Requirement
   def to_dependency
     f = self.class.default_formula
     raise "No default formula defined for #{inspect}" if f.nil?
-    if HOMEBREW_TAP_FORMULA_REGEX === f
+    if f =~ HOMEBREW_TAP_FORMULA_REGEX
       TapDependency.new(f, tags, method(:modify_build_environment), name)
     else
       Dependency.new(f, tags, method(:modify_build_environment), name)
@@ -199,11 +198,8 @@ class Requirement
 
       formulae.each do |f|
         f.requirements.each do |req|
-          if prune?(f, req, &block)
-            next
-          else
-            reqs << req
-          end
+          next if prune?(f, req, &block)
+          reqs << req
         end
       end
 
diff --git a/Library/Homebrew/requirements.rb b/Library/Homebrew/requirements.rb
index 68d21a2b7..274ba5c9b 100644
--- a/Library/Homebrew/requirements.rb
+++ b/Library/Homebrew/requirements.rb
@@ -22,7 +22,7 @@ class XcodeRequirement < Requirement
   satisfy(build_env: false) { xcode_installed_version }
 
   def initialize(tags)
-    @version = tags.find { |t| tags.delete(t) if /(\d\.)+\d/ === t }
+    @version = tags.find { |tag| tags.delete(tag) if tag =~ /(\d\.)+\d/ }
     super
   end
 
@@ -39,11 +39,11 @@ class XcodeRequirement < Requirement
       Installing just the Command Line Tools is not sufficient.
     EOS
     if MacOS.version >= :lion
-      message += <<-EOS.undent
+      message + <<-EOS.undent
         Xcode can be installed from the App Store.
       EOS
     else
-      message += <<-EOS.undent
+      message + <<-EOS.undent
         Xcode can be installed from https://developer.apple.com/xcode/downloads/
       EOS
     end
diff --git a/Library/Homebrew/requirements/python_requirement.rb b/Library/Homebrew/requirements/python_requirement.rb
index 5d79f2a18..696b9c800 100644
--- a/Library/Homebrew/requirements/python_requirement.rb
+++ b/Library/Homebrew/requirements/python_requirement.rb
@@ -50,7 +50,7 @@ class PythonRequirement < Requirement
   end
 
   # Deprecated
-  alias_method :to_s, :python_binary
+  alias to_s python_binary
 end
 
 class Python3Requirement < PythonRequirement
diff --git a/Library/Homebrew/sandbox.rb b/Library/Homebrew/sandbox.rb
index 9392b7122..4d0709cb4 100644
--- a/Library/Homebrew/sandbox.rb
+++ b/Library/Homebrew/sandbox.rb
@@ -3,8 +3,12 @@ require "tempfile"
 
 class Sandbox
   SANDBOX_EXEC = "/usr/bin/sandbox-exec".freeze
-  SANDBOXED_TAPS = [
-    "homebrew/core",
+  SANDBOXED_TAPS = %w[
+    homebrew/core
+    homebrew/dupes
+    homebrew/fuse
+    homebrew/devel-only
+    homebrew/tex
   ].freeze
 
   def self.available?
@@ -73,17 +77,21 @@ class Sandbox
 
   # Xcode projects expect access to certain cache/archive dirs.
   def allow_write_xcode
-    allow_write_path "/Users/#{ENV["USER"]}/Library/Developer/Xcode/DerivedData/"
+    allow_write_path "/Users/#{ENV["USER"]}/Library/Developer"
   end
 
   def allow_write_log(formula)
     allow_write_path formula.logs
   end
 
-  def deny_write_homebrew_library
-    deny_write_path HOMEBREW_LIBRARY
-    deny_write_path HOMEBREW_REPOSITORY/".git"
+  def deny_write_homebrew_repository
     deny_write HOMEBREW_BREW_FILE
+    if HOMEBREW_PREFIX.to_s != HOMEBREW_REPOSITORY.to_s
+      deny_write_path HOMEBREW_REPOSITORY
+    else
+      deny_write_path HOMEBREW_LIBRARY
+      deny_write_path HOMEBREW_REPOSITORY/".git"
+    end
   end
 
   def exec(*args)
diff --git a/Library/Homebrew/software_spec.rb b/Library/Homebrew/software_spec.rb
index 986dc5354..bb432e2dd 100644
--- a/Library/Homebrew/software_spec.rb
+++ b/Library/Homebrew/software_spec.rb
@@ -65,11 +65,12 @@ class SoftwareSpec
   end
 
   def bottle_unneeded?
-    !!@bottle_disable_reason && @bottle_disable_reason.unneeded?
+    return false unless @bottle_disable_reason
+    @bottle_disable_reason.unneeded?
   end
 
   def bottle_disabled?
-    !!@bottle_disable_reason
+    @bottle_disable_reason ? true : false
   end
 
   attr_reader :bottle_disable_reason
@@ -116,12 +117,12 @@ class SoftwareSpec
 
   def option(name, description = "")
     opt = PREDEFINED_OPTIONS.fetch(name) do
-      if Symbol === name
+      if name.is_a?(Symbol)
         opoo "Passing arbitrary symbols to `option` is deprecated: #{name.inspect}"
         puts "Symbols are reserved for future use, please pass a string instead"
         name = name.to_s
       end
-      unless String === name
+      unless name.is_a?(String)
         raise ArgumentError, "option name must be string or symbol; got a #{name.class}: #{name}"
       end
       raise ArgumentError, "option name is required" if name.empty?
@@ -227,7 +228,7 @@ class Bottle
     def to_s
       prefix + suffix
     end
-    alias_method :to_str, :to_s
+    alias to_str to_s
 
     def prefix
       "#{name}-#{version}.#{tag}"
@@ -318,7 +319,7 @@ class BottleSpecification
   end
 
   def tag?(tag)
-    !!checksum_for(tag)
+    checksum_for(tag) ? true : false
   end
 
   # Checksum methods in the DSL's bottle block optionally take
diff --git a/Library/Homebrew/system_config.rb b/Library/Homebrew/system_config.rb
index a8b4ee1ff..555493c0d 100644
--- a/Library/Homebrew/system_config.rb
+++ b/Library/Homebrew/system_config.rb
@@ -152,7 +152,7 @@ class SystemConfig
       f.puts "Ruby: #{describe_ruby}"
       f.puts "Java: #{describe_java}"
     end
-    alias_method :dump_generic_verbose_config, :dump_verbose_config
+    alias dump_generic_verbose_config dump_verbose_config
   end
 end
 
diff --git a/Library/Homebrew/tab.rb b/Library/Homebrew/tab.rb
index 12b23cc73..379f2e8a4 100644
--- a/Library/Homebrew/tab.rb
+++ b/Library/Homebrew/tab.rb
@@ -328,9 +328,9 @@ class Tab < OpenStruct
     else
       s << "Built from source"
     end
-    if time
-      s << Time.at(time).strftime("on %Y-%m-%d at %H:%M:%S")
-    end
+
+    s << Time.at(time).strftime("on %Y-%m-%d at %H:%M:%S") if time
+
     unless used_options.empty?
       s << "with:"
       s << used_options.to_a.join(" ")
diff --git a/Library/Homebrew/tap.rb b/Library/Homebrew/tap.rb
index ecf81ca37..c73e3f7a7 100644
--- a/Library/Homebrew/tap.rb
+++ b/Library/Homebrew/tap.rb
@@ -130,9 +130,8 @@ class Tap
   # The issues URL of this {Tap}.
   # e.g. `https://github.com/user/homebrew-repo/issues`
   def issues_url
-    if official? || !custom_remote?
-      "https://github.com/#{user}/homebrew-#{repo}/issues"
-    end
+    return unless official? || !custom_remote?
+    "https://github.com/#{user}/homebrew-#{repo}/issues"
   end
 
   def to_s
@@ -236,15 +235,16 @@ class Tap
     puts "Tapped #{formula_count} formula#{plural(formula_count, "e")} (#{path.abv})" unless quiet
     Descriptions.cache_formulae(formula_names)
 
-    if !options[:clone_target] && private? && !quiet
-      puts <<-EOS.undent
-        It looks like you tapped a private repository. To avoid entering your
-        credentials each time you update, you can use git HTTP credential
-        caching or issue the following command:
-          cd #{path}
-          git remote set-url origin git@github.com:#{user}/homebrew-#{repo}.git
-      EOS
-    end
+    return if options[:clone_target]
+    return unless private?
+    return if quiet
+    puts <<-EOS.undent
+      It looks like you tapped a private repository. To avoid entering your
+      credentials each time you update, you can use git HTTP credential
+      caching or issue the following command:
+        cd #{path}
+        git remote set-url origin git@github.com:#{user}/homebrew-#{repo}.git
+    EOS
   end
 
   def link_manpages
diff --git a/Library/Homebrew/test/Gemfile b/Library/Homebrew/test/Gemfile
index b7666e551..0a84f8dc2 100644
--- a/Library/Homebrew/test/Gemfile
+++ b/Library/Homebrew/test/Gemfile
@@ -3,15 +3,17 @@ source "https://rubygems.org"
 gem "mocha", "~> 1.1"
 gem "minitest", "~> 5.3"
 gem "rake", "~> 10.3"
+gem "parallel_tests", "~> 2.9"
 
 group :coverage do
-  # This is SimpleCov v0.12.0 with one PR merged on top, that finally resolves
+  # This is SimpleCov v0.12.0 with two fixes merged on top, that finally resolve
   # all issues with parallel tests, uncovered files, and tracked files. Switch
-  # back to stable as soon as v0.12.1 or v0.13.0 is released. See pull request
-  # <https://github.com/Homebrew/legacy-homebrew/pull/48250> for full details.
+  # back to stable as soon as v0.12.1 or v0.13.0 is released. For details, see:
+  #  - https://github.com/colszowka/simplecov/pull/513
+  #  - https://github.com/colszowka/simplecov/pull/520
   gem "simplecov", "0.12.0",
     git: "https://github.com/colszowka/simplecov.git",
-    branch: "master", # commit 257e26394c464c4ab388631b4eff1aa98c37d3f1
+    branch: "master", # commit 83d8031ddde0927f87ef9327200a98583ca18d77
     require: false
   gem "codecov", require: false
 end
diff --git a/Library/Homebrew/test/Gemfile.lock b/Library/Homebrew/test/Gemfile.lock
index ceb11128d..ba639d70f 100644
--- a/Library/Homebrew/test/Gemfile.lock
+++ b/Library/Homebrew/test/Gemfile.lock
@@ -1,6 +1,6 @@
 GIT
   remote: https://github.com/colszowka/simplecov.git
-  revision: 257e26394c464c4ab388631b4eff1aa98c37d3f1
+  revision: 83d8031ddde0927f87ef9327200a98583ca18d77
   branch: master
   specs:
     simplecov (0.12.0)
@@ -21,6 +21,9 @@ GEM
     minitest (5.9.0)
     mocha (1.1.0)
       metaclass (~> 0.0.1)
+    parallel (1.9.0)
+    parallel_tests (2.9.0)
+      parallel
     rake (10.5.0)
     simplecov-html (0.10.0)
     url (0.3.2)
@@ -32,8 +35,9 @@ DEPENDENCIES
   codecov
   minitest (~> 5.3)
   mocha (~> 1.1)
+  parallel_tests (~> 2.9)
   rake (~> 10.3)
   simplecov (= 0.12.0)!
 
 BUNDLED WITH
-   1.12.5
+   1.13.1
diff --git a/Library/Homebrew/test/Rakefile b/Library/Homebrew/test/Rakefile
deleted file mode 100644
index a2db861f2..000000000
--- a/Library/Homebrew/test/Rakefile
+++ /dev/null
@@ -1,29 +0,0 @@
-require "rake"
-require "rake/testtask"
-
-def mac?
-  return false if ENV["HOMEBREW_TEST_GENERIC_OS"]
-  RUBY_PLATFORM.to_s.downcase.include? "darwin"
-end
-
-TEST_DIRECTORY = File.dirname(File.expand_path(__FILE__))
-TEST_FILES = Dir["#{TEST_DIRECTORY}/test_*.rb"].reject do |f|
-  f.include?("/test_os_mac_") && !mac?
-end
-
-task default: :test
-
-Rake::TestTask.new(:test) do |t|
-  t.libs << TEST_DIRECTORY
-  t.test_files = TEST_FILES
-end
-
-namespace :test do
-  TEST_FILES.each do |file|
-    name = file[/test_(.+)\.rb/, 1]
-    Rake::TestTask.new(name) do |t|
-      t.libs << TEST_DIRECTORY
-      t.test_files = [file]
-    end
-  end
-end
diff --git a/Library/Homebrew/test/test_cmd_testbot.rb b/Library/Homebrew/test/test_cmd_testbot.rb
deleted file mode 100644
index d762448d1..000000000
--- a/Library/Homebrew/test/test_cmd_testbot.rb
+++ /dev/null
@@ -1,99 +0,0 @@
-require "pathname"
-
-require "testing_env"
-require "dev-cmd/test-bot"
-
-class TestbotCommandTests < Homebrew::TestCase
-  def test_resolve_test_tap
-    tap = Homebrew.resolve_test_tap
-    assert_nil tap, "Should return nil if no tap slug provided"
-
-    slug = "spam/homebrew-eggs"
-    url = "https://github.com/#{slug}.git"
-    environments = [
-      { "TRAVIS_REPO_SLUG" => slug },
-      { "UPSTREAM_BOT_PARAMS" => "--tap=#{slug}" },
-      { "UPSTREAM_BOT_PARAMS" => "--tap=spam/eggs" },
-      { "UPSTREAM_GIT_URL" => url },
-      { "GIT_URL" => url },
-    ]
-
-    predicate = proc do |message|
-      tap = Homebrew.resolve_test_tap
-      assert_kind_of Tap, tap, message
-      assert_equal tap.user, "spam", message
-      assert_equal tap.repo, "eggs", message
-    end
-
-    environments.each do |pair|
-      with_environment(pair) do
-        predicate.call pair.to_s
-      end
-    end
-
-    ARGV.expects(:value).with("tap").returns(slug)
-    predicate.call "ARGV"
-  end
-end
-
-class TestbotStepTests < Homebrew::TestCase
-  def run
-    [nil, "1"].each do |travis|
-      with_environment("TRAVIS" => travis) { super }
-    end
-    self
-  end
-
-  def teardown
-    unless passed?
-      raise "INFO: Previous test failed with ENV['TRAVIS'] = #{ENV["TRAVIS"].inspect}"
-    end
-  end
-
-  def stub_test_instance
-    stub(
-      category: "stub",
-      log_root: Pathname.pwd
-    )
-  end
-
-  def test_step_run_measures_execution_time
-    step = Homebrew::Step.new stub_test_instance, %w[sleep 0.1]
-    shutup do
-      step.run
-    end
-    assert_operator step.time, :>, 0.1
-    assert_operator step.time, :<, 1
-    assert_equal step.passed?, true
-  end
-
-  def test_step_run_observes_failure
-    step = Homebrew::Step.new stub_test_instance, ["false", ""]
-    shutup do
-      step.run
-    end
-    assert_equal step.passed?, false
-    assert_equal step.failed?, true
-  end
-
-  def test_step_dry_run_is_dry_and_always_succeeds
-    step = Homebrew::Step.new stub_test_instance, ["false", ""]
-    ARGV.expects(:include?).with("--dry-run").returns(true)
-    step.stubs(:fork).raises("Dry run isn't dry!")
-    shutup do
-      step.run
-    end
-    assert_equal step.passed?, true
-  end
-
-  def test_step_fail_fast_exits_on_failure
-    step = Homebrew::Step.new stub_test_instance, ["false", ""]
-    ARGV.stubs(:include?).returns(false)
-    ARGV.expects(:include?).with("--fail-fast").returns(true)
-    step.expects(:exit).with(1).returns(nil)
-    shutup do
-      step.run
-    end
-    assert_equal step.passed?, false
-  end
-end
diff --git a/Library/Homebrew/test/test_dependency_collector.rb b/Library/Homebrew/test/test_dependency_collector.rb
index a94b4959e..4e87c8515 100644
--- a/Library/Homebrew/test/test_dependency_collector.rb
+++ b/Library/Homebrew/test/test_dependency_collector.rb
@@ -76,6 +76,11 @@ class DependencyCollectorTests < Homebrew::TestCase
     assert_predicate dep, :optional?
   end
 
+  def test_ant_dep
+    @d.add ant: :build
+    assert_equal find_dependency("ant"), Dependency.new("ant", [:build])
+  end
+
   def test_raises_typeerror_for_unknown_classes
     assert_raises(TypeError) { @d.add(Class.new) }
   end
diff --git a/Library/Homebrew/test/test_diagnostic.rb b/Library/Homebrew/test/test_diagnostic.rb
index 5d0f5f386..37f56e961 100644
--- a/Library/Homebrew/test/test_diagnostic.rb
+++ b/Library/Homebrew/test/test_diagnostic.rb
@@ -154,7 +154,7 @@ class DiagnosticChecksTest < Homebrew::TestCase
   def test_check_dyld_vars
     ENV["DYLD_INSERT_LIBRARIES"] = "foo"
     assert_match "Setting DYLD_INSERT_LIBRARIES",
-      @checks.check_DYLD_vars
+      @checks.check_dyld_vars
   end
 
   def test_check_for_symlinked_cellar
diff --git a/Library/Homebrew/test/test_download_strategies.rb b/Library/Homebrew/test/test_download_strategies.rb
index d107d14e8..87218fb12 100644
--- a/Library/Homebrew/test/test_download_strategies.rb
+++ b/Library/Homebrew/test/test_download_strategies.rb
@@ -118,7 +118,7 @@ class GitDownloadStrategyTests < Homebrew::TestCase
 
   def test_source_modified_time
     setup_git_repo
-    assert_equal 1242860651, @strategy.source_modified_time.to_i
+    assert_equal 1_242_860_651, @strategy.source_modified_time.to_i
   end
 
   def test_last_commit
diff --git a/Library/Homebrew/test/test_formula.rb b/Library/Homebrew/test/test_formula.rb
index 9207f8ead..37d3f0f59 100644
--- a/Library/Homebrew/test/test_formula.rb
+++ b/Library/Homebrew/test/test_formula.rb
@@ -467,7 +467,7 @@ class FormulaTests < Homebrew::TestCase
     assert_version_equal "HEAD", f.head.version
   end
 
-  def test_formula_set_active_spec
+  def test_formula_active_spec=
     f = formula do
       url "foo"
       version "1.0"
@@ -481,11 +481,11 @@ class FormulaTests < Homebrew::TestCase
     assert_equal :stable, f.active_spec_sym
     assert_equal f.stable, f.send(:active_spec)
     assert_equal "1.0_1", f.pkg_version.to_s
-    f.set_active_spec(:devel)
+    f.active_spec = :devel
     assert_equal :devel, f.active_spec_sym
     assert_equal f.devel, f.send(:active_spec)
     assert_equal "1.0beta_1", f.pkg_version.to_s
-    assert_raises(FormulaSpecificationError) { f.set_active_spec(:head) }
+    assert_raises(FormulaSpecificationError) { f.active_spec = :head }
   end
 
   def test_path
diff --git a/Library/Homebrew/test/test_inreplace.rb b/Library/Homebrew/test/test_inreplace.rb
index 91d57f942..0e62f9d3f 100644
--- a/Library/Homebrew/test/test_inreplace.rb
+++ b/Library/Homebrew/test/test_inreplace.rb
@@ -91,26 +91,29 @@ class InreplaceTest < Homebrew::TestCase
   end
 
   def test_inreplace_errors
+    require "tempfile"
     extend(Utils::Inreplace)
 
-    open("test", "w") { |f| f.write "a\nb\nc\n" }
+    file = Tempfile.new("test")
+
+    file.write "a\nb\nc\n"
 
     assert_raises(Utils::InreplaceError) do
-      inreplace "test", "d", "f"
+      inreplace file.path, "d", "f"
     end
 
     assert_raises(Utils::InreplaceError) do
       # Under current context, we are testing `String#gsub!`, so let's disable rubocop temporarily.
-      inreplace("test") { |s| s.gsub!("d", "f") } # rubocop:disable Performance/StringReplacement
+      inreplace(file.path) { |s| s.gsub!("d", "f") } # rubocop:disable Performance/StringReplacement
     end
 
     assert_raises(Utils::InreplaceError) do
-      inreplace("test") do |s|
+      inreplace(file.path) do |s|
         s.change_make_var! "VAR", "value"
         s.remove_make_var! "VAR2"
       end
     end
   ensure
-    File.unlink("test")
+    file.unlink
   end
 end
diff --git a/Library/Homebrew/test/test_integration_cmds.rb b/Library/Homebrew/test/test_integration_cmds.rb
index 11eb6c69d..35ad04e7a 100644
--- a/Library/Homebrew/test/test_integration_cmds.rb
+++ b/Library/Homebrew/test/test_integration_cmds.rb
@@ -39,9 +39,8 @@ class IntegrationCommandTests < Homebrew::TestCase
   end
 
   def needs_test_cmd_taps
-    unless ENV["HOMEBREW_TEST_OFFICIAL_CMD_TAPS"]
-      skip "HOMEBREW_TEST_OFFICIAL_CMD_TAPS is not set"
-    end
+    return if ENV["HOMEBREW_TEST_OFFICIAL_CMD_TAPS"]
+    skip "HOMEBREW_TEST_OFFICIAL_CMD_TAPS is not set"
   end
 
   def needs_macos
@@ -274,8 +273,8 @@ class IntegrationCommandTests < Homebrew::TestCase
                  cmd("help", "cat")) # Internal command (documented, Ruby).
     assert_match(/^brew update /,
                  cmd("help", "update")) # Internal command (documented, Shell).
-    assert_match(/^brew test-bot /,
-                 cmd("help", "test-bot")) # Internal developer command (documented, Ruby).
+    assert_match(/^brew update-test /,
+                 cmd("help", "update-test")) # Internal developer command (documented, Ruby).
   end
 
   def test_config
diff --git a/Library/Homebrew/test/test_os_mac_dependency_collector.rb b/Library/Homebrew/test/test_os_mac_dependency_collector.rb
index 37b619101..05b466c94 100644
--- a/Library/Homebrew/test/test_os_mac_dependency_collector.rb
+++ b/Library/Homebrew/test/test_os_mac_dependency_collector.rb
@@ -2,6 +2,10 @@ require "testing_env"
 require "dependency_collector"
 
 class OSMacDependencyCollectorTests < Homebrew::TestCase
+  def find_dependency(name)
+    @d.deps.find { |dep| dep.name == name }
+  end
+
   def setup
     @d = DependencyCollector.new
   end
@@ -19,4 +23,16 @@ class OSMacDependencyCollectorTests < Homebrew::TestCase
     MacOS.stubs(:version).returns(MacOS::Version.new("10.5"))
     assert_nil @d.build(:ld64)
   end
+
+  def test_ant_dep_mavericks_or_newer
+    MacOS.stubs(:version).returns(MacOS::Version.new("10.9"))
+    @d.add ant: :build
+    assert_equal find_dependency("ant"), Dependency.new("ant", [:build])
+  end
+
+  def test_ant_dep_pre_mavericks
+    MacOS.stubs(:version).returns(MacOS::Version.new("10.7"))
+    @d.add ant: :build
+    assert_nil find_dependency("ant")
+  end
 end
diff --git a/Library/Homebrew/test/test_pathname.rb b/Library/Homebrew/test/test_pathname.rb
index bc13241a7..2f6360719 100644
--- a/Library/Homebrew/test/test_pathname.rb
+++ b/Library/Homebrew/test/test_pathname.rb
@@ -26,7 +26,7 @@ class PathnameTests < Homebrew::TestCase
     mkdir_p @dir/"a-directory"
     touch @dir/".DS_Store"
     touch @dir/"a-file"
-    File.truncate(@dir/"a-file", 1048576)
+    File.truncate(@dir/"a-file", 1_048_576)
     ln_s @dir/"a-file", @dir/"a-symlink"
     ln @dir/"a-file", @dir/"a-hardlink"
     assert_equal 3, @dir.file_count
diff --git a/Library/Homebrew/test/test_versions.rb b/Library/Homebrew/test/test_versions.rb
index 2a1a33a59..21bf324a3 100644
--- a/Library/Homebrew/test/test_versions.rb
+++ b/Library/Homebrew/test/test_versions.rb
@@ -63,6 +63,8 @@ class VersionComparisonTests < Homebrew::TestCase
   end
 
   def test_comparing_alpha_versions
+    assert_operator version("1.2.3alpha"), :<, version("1.2.3")
+    assert_operator version("1.2.3"), :<, version("1.2.3a")
     assert_operator version("1.2.3alpha4"), :==, version("1.2.3a4")
     assert_operator version("1.2.3alpha4"), :==, version("1.2.3A4")
     assert_operator version("1.2.3alpha4"), :>, version("1.2.3alpha3")
@@ -203,6 +205,10 @@ class VersionParsingTests < Homebrew::TestCase
     assert_version_detected "0.7.1", "https://codeload.github.com/gsamokovarov/jump/tar.gz/v0.7.1"
   end
 
+  def test_elasticsearch_alpha_style
+    assert_version_detected "5.0.0-alpha5", "https://download.elastic.co/elasticsearch/release/org/elasticsearch/distribution/tar/elasticsearch/5.0.0-alpha5/elasticsearch-5.0.0-alpha5.tar.gz"
+  end
+
   def test_gloox_beta_style
     assert_version_detected "1.0-beta7", "http://camaya.net/download/gloox-1.0-beta7.tar.bz2"
   end
diff --git a/Library/Homebrew/test/testing_env.rb b/Library/Homebrew/test/testing_env.rb
index 164c812ea..02264aa39 100644
--- a/Library/Homebrew/test/testing_env.rb
+++ b/Library/Homebrew/test/testing_env.rb
@@ -15,6 +15,7 @@ TEST_DIRECTORY = File.dirname(File.expand_path(__FILE__))
 begin
   require "rubygems"
   require "minitest/autorun"
+  require "parallel_tests/test/runtime_logger"
   require "mocha/setup"
 rescue LoadError
   abort "Run `bundle install` or install the mocha and minitest gems before running the tests"
@@ -42,7 +43,7 @@ module Homebrew
   module FSLeakLogger
     def self.included(klass)
       require "find"
-      @@log = File.open("fs_leak_log", "w")
+      @@log = File.open("#{__dir__}/fs_leak_log", "w")
       klass.make_my_diffs_pretty!
     end
 
@@ -56,9 +57,8 @@ module Homebrew
       super
       files_after_test = []
       Find.find(TEST_TMPDIR) { |f| files_after_test << f.sub(TEST_TMPDIR, "") }
-      if @__files_before_test != files_after_test
-        @@log.puts location, diff(@__files_before_test, files_after_test)
-      end
+      return if @__files_before_test == files_after_test
+      @@log.puts location, diff(@__files_before_test, files_after_test)
     end
   end
 
diff --git a/Library/Homebrew/utils.rb b/Library/Homebrew/utils.rb
index e466f8a08..58083fe1b 100644
--- a/Library/Homebrew/utils.rb
+++ b/Library/Homebrew/utils.rb
@@ -218,13 +218,9 @@ def interactive_shell(f = nil)
 
   Process.wait fork { exec ENV["SHELL"] }
 
-  if $?.success?
-    return
-  elsif $?.exited?
-    raise "Aborted due to non-zero exit status (#{$?.exitstatus})"
-  else
-    raise $?.inspect
-  end
+  return if $?.success?
+  raise "Aborted due to non-zero exit status (#{$?.exitstatus})" if $?.exited?
+  raise $?.inspect
 end
 
 module Homebrew
@@ -248,15 +244,6 @@ module Homebrew
     _system(cmd, *args)
   end
 
-  def self.homebrew_version_string
-    if pretty_revision = HOMEBREW_REPOSITORY.git_short_head
-      last_commit = HOMEBREW_REPOSITORY.git_last_commit_date
-      "#{HOMEBREW_VERSION} (git revision #{pretty_revision}; last commit #{last_commit})"
-    else
-      "#{HOMEBREW_VERSION} (no git repository)"
-    end
-  end
-
   def self.core_tap_version_string
     require "tap"
     tap = CoreTap.instance
@@ -334,13 +321,12 @@ module Homebrew
       end
     end
 
-    if $times.nil?
-      $times = {}
-      at_exit do
-        col_width = [$times.keys.map(&:size).max + 2, 15].max
-        $times.sort_by { |_k, v| v }.each do |method, time|
-          puts format("%-*s %0.4f sec", col_width, "#{method}:", time)
-        end
+    return unless $times.nil?
+    $times = {}
+    at_exit do
+      col_width = [$times.keys.map(&:size).max + 2, 15].max
+      $times.sort_by { |_k, v| v }.each do |method, time|
+        puts format("%-*s %0.4f sec", col_width, "#{method}:", time)
       end
     end
   end
@@ -617,14 +603,14 @@ def link_src_dst_dirs(src_dir, dst_dir, command, link_dir: false)
     dst_dir.parent.mkpath
     dst.make_relative_symlink(src)
   end
-  unless conflicts.empty?
-    onoe <<-EOS.undent
-      Could not link:
-      #{conflicts.join("\n")}
 
-      Please delete these paths and run `#{command}`.
-    EOS
-  end
+  return if conflicts.empty?
+  onoe <<-EOS.undent
+    Could not link:
+    #{conflicts.join("\n")}
+
+    Please delete these paths and run `#{command}`.
+  EOS
 end
 
 def link_path_manpages(path, command)
diff --git a/Library/Homebrew/utils/git.rb b/Library/Homebrew/utils/git.rb
index 837cc22e4..dfe47f890 100644
--- a/Library/Homebrew/utils/git.rb
+++ b/Library/Homebrew/utils/git.rb
@@ -22,9 +22,7 @@ module Utils
     return if git_available?
 
     # we cannot install brewed git if homebrew/core is unavailable.
-    unless CoreTap.instance.installed?
-      raise "Git is unavailable"
-    end
+    raise "Git is unavailable" unless CoreTap.instance.installed?
 
     begin
       oh1 "Installing git"
diff --git a/Library/Homebrew/utils/github.rb b/Library/Homebrew/utils/github.rb
index 654272363..b7ec538f9 100644
--- a/Library/Homebrew/utils/github.rb
+++ b/Library/Homebrew/utils/github.rb
@@ -2,7 +2,8 @@ require "uri"
 require "tempfile"
 
 module GitHub
-  extend self
+  module_function
+
   ISSUES_URI = URI.parse("https://api.github.com/search/issues")
 
   Error = Class.new(RuntimeError)
diff --git a/Library/Homebrew/utils/json.rb b/Library/Homebrew/utils/json.rb
index 8a8cb6847..19d32a1e1 100644
--- a/Library/Homebrew/utils/json.rb
+++ b/Library/Homebrew/utils/json.rb
@@ -2,7 +2,7 @@ require "vendor/okjson"
 
 module Utils
   module JSON
-    extend self
+    module_function
 
     Error = Class.new(StandardError)
 
diff --git a/Library/Homebrew/utils/popen.rb b/Library/Homebrew/utils/popen.rb
index 76e67b3a9..350d9a09f 100644
--- a/Library/Homebrew/utils/popen.rb
+++ b/Library/Homebrew/utils/popen.rb
@@ -14,11 +14,8 @@ module Utils
   def self.popen(args, mode)
     IO.popen("-", mode) do |pipe|
       if pipe
-        if block_given?
-          yield pipe
-        else
-          return pipe.read
-        end
+        return pipe.read unless block_given?
+        yield pipe
       else
         $stderr.reopen("/dev/null", "w")
         exec(*args)
diff --git a/Library/Homebrew/version.rb b/Library/Homebrew/version.rb
index 520db6626..60a833609 100644
--- a/Library/Homebrew/version.rb
+++ b/Library/Homebrew/version.rb
@@ -95,7 +95,7 @@ class Version
   end
 
   class AlphaToken < CompositeToken
-    PATTERN = /a(?:lpha)?[0-9]*/i
+    PATTERN = /alpha[0-9]*|a[0-9]+/i
 
     def <=>(other)
       case other
@@ -108,7 +108,7 @@ class Version
   end
 
   class BetaToken < CompositeToken
-    PATTERN = /b(?:eta)?[0-9]*/i
+    PATTERN = /beta[0-9]*|b[0-9]+/i
 
     def <=>(other)
       case other
@@ -192,11 +192,10 @@ class Version
   end
 
   def initialize(val)
-    if val.respond_to?(:to_str)
-      @version = val.to_str
-    else
+    unless val.respond_to?(:to_str)
       raise TypeError, "Version value must be a string; got a #{val.class} (#{val})"
     end
+    @version = val.to_str
   end
 
   def detected_from_url?
@@ -208,7 +207,7 @@ class Version
   end
 
   def <=>(other)
-    return unless Version === other
+    return unless other.is_a?(Version)
     return 0 if version == other.version
     return 1 if head? && !other.head?
     return -1 if !head? && other.head?
@@ -242,7 +241,7 @@ class Version
 
     0
   end
-  alias_method :eql?, :==
+  alias eql? ==
 
   def hash
     version.hash
@@ -251,7 +250,7 @@ class Version
   def to_s
     version.dup
   end
-  alias_method :to_str, :to_s
+  alias to_str to_s
 
   protected
 
@@ -340,8 +339,8 @@ class Version
     m = /-((?:\d+\.)*\d+(?:[abc]|rc|RC)\d*)$/.match(stem)
     return m.captures.first unless m.nil?
 
-    # e.g. foobar-4.5.0-beta1, or foobar-4.50-beta
-    m = /-((?:\d+\.)*\d+-beta\d*)$/.match(stem)
+    # e.g. foobar-4.5.0-alpha5, foobar-4.5.0-beta1, or foobar-4.50-beta
+    m = /-((?:\d+\.)*\d+-(?:alpha|beta|rc)\d*)$/.match(stem)
     return m.captures.first unless m.nil?
 
     # e.g. http://ftpmirror.gnu.org/libidn/libidn-1.29-win64.zip
@@ -386,7 +385,7 @@ class Version
 
     # e.g. http://mirrors.jenkins-ci.org/war/1.486/jenkins.war
     # e.g. https://github.com/foo/bar/releases/download/0.10.11/bar.phar
-    m = /\/(\d\.\d+(\.\d+)?)\//.match(spec_s)
+    m = %r{/(\d\.\d+(\.\d+)?)}.match(spec_s)
     return m.captures.first unless m.nil?
 
     # e.g. http://www.ijg.org/files/jpegsrc.v8d.tar.gz
diff --git a/README.md b/README.md
index 0c0ce0a2a..ef7232040 100644
--- a/README.md
+++ b/README.md
@@ -40,7 +40,7 @@ This is our PGP key which is valid until May 24, 2017.
 ## Who Are You?
 Homebrew's lead maintainer is [Mike McQuaid](https://github.com/mikemcquaid).
 
-Homebrew's current maintainers are [Misty De Meo](https://github.com/mistydemeo), [Andrew Janke](https://github.com/apjanke), [Xu Cheng](https://github.com/xu-cheng), [Tomasz Pajor](https://github.com/nijikon), [Baptiste Fontaine](https://github.com/bfontaine), [Zhiming Wang](https://github.com/zmwangx), [Brett Koonce](https://github.com/asparagui), [ilovezfs](https://github.com/ilovezfs), [Martin Afanasjew](https://github.com/UniqMartin), [Uladzislau Shablinski](https://github.com/orgs/Homebrew/people/vladshablinsky), [Dominyk Tiller](https://github.com/DomT4), [Tim Smith](https://github.com/tdsmith) and [Alex Dunn](https://github.com/dunn).
+Homebrew's current maintainers are [Misty De Meo](https://github.com/mistydemeo), [Andrew Janke](https://github.com/apjanke), [Xu Cheng](https://github.com/xu-cheng), [Tomasz Pajor](https://github.com/nijikon), [Baptiste Fontaine](https://github.com/bfontaine), [Zhiming Wang](https://github.com/zmwangx), [Brett Koonce](https://github.com/asparagui), [ilovezfs](https://github.com/ilovezfs), [Martin Afanasjew](https://github.com/UniqMartin), [Uladzislau Shablinski](https://github.com/vladshablinsky), [Dominyk Tiller](https://github.com/DomT4), [Tim Smith](https://github.com/tdsmith) and [Alex Dunn](https://github.com/dunn).
 
 Former maintainers with significant contributions include [Jack Nagel](https://github.com/jacknagel), [Adam Vandenberg](https://github.com/adamv) and Homebrew's creator: [Max Howell](https://github.com/mxcl).
 
diff --git a/docs/README.md b/docs/README.md
index 740f73ea3..ac9dbcd79 100644
--- a/docs/README.md
+++ b/docs/README.md
@@ -7,8 +7,9 @@ Homebrew installs the stuff you need that Apple didn’t.
 - [Gems, Eggs and Perl Modules](Gems,-Eggs-and-Perl-Modules.md)
 - [Homebrew and Python](Homebrew-and-Python.md)
 
-Please note: Homebrew is not 1.0 yet. Generally it works well, but when
-it doesn’t we’d hope you report the bug.
+Please note: Homebrew generally works well, but when it doesn’t we’d hope you
+report the bug.
+
 ## Troubleshooting
 First, please run `brew update` (twice) and `brew doctor`.
 
diff --git a/docs/Xcode.md b/docs/Xcode.md
index 98c5c6347..7697a9c55 100644
--- a/docs/Xcode.md
+++ b/docs/Xcode.md
@@ -10,7 +10,7 @@ Tools available for your platform:
  10.8  | 5.1.1 | April 2014
  10.9  | 6.2   | 6.2
  10.10 | 7.2.1 | 7.2
- 10.11 | 7.3.1 | 7.3
+ 10.11 | 8.0   | 7.3
  10.12 | 8.0   | 8.0
 
 
diff --git a/docs/brew.1.html b/docs/brew.1.html
index b6c4be718..1aee073c1 100644
--- a/docs/brew.1.html
+++ b/docs/brew.1.html
@@ -552,7 +552,7 @@ Each &lt;patch-source> may be one of:
 
 <dl>
 <dt><code>tap_readme</code> [<code>-v</code>] <var>name</var></dt><dd><p>Generate the README.md file for a new tap.</p></dd>
-<dt><code>test</code> [<code>--devel</code>|<code>--HEAD</code>] [<code>--debug</code>] [<code>--keep-tmp</code>] <var>formula</var></dt><dd><p>A few formulae provide a test method. <code>brew test</code> <var>formula</var> runs this
+<dt><code>test</code> [<code>--devel</code>|<code>--HEAD</code>] [<code>--debug</code>] [<code>--keep-tmp</code>] <var>formula</var></dt><dd><p>Most formulae provide a test method. <code>brew test</code> <var>formula</var> runs this
 test method. There is no standard output or return code, but it should
 generally indicate to the user if something is wrong with the installed
 formula.</p>
@@ -568,11 +568,11 @@ not deleted.</p>
 
 <p>Example: <code>brew install jruby &amp;&amp; brew test jruby</code></p></dd>
 <dt><code>tests</code> [<code>-v</code>] [<code>--coverage</code>] [<code>--generic</code>] [<code>--no-compat</code>] [<code>--only=</code><test_script/test_method>] [<code>--seed</code> <var>seed</var>] [<code>--trace</code>] [<code>--online</code>] [<code>--official-cmd-taps</code>]</dt><dd><p>Run Homebrew's unit and integration tests.</p></dd>
-<dt><code>update-test</code> [<code>--commit=&lt;sha1></code>] [<code>--before=&lt;date></code>] [<code>--keep-tmp</code>]</dt><dd><p>Runs a test of <code>brew update</code> with a new repository clone.</p>
+<dt><code>update-test</code> [<code>--commit=&lt;commit></code>] [<code>--before=&lt;date></code>] [<code>--keep-tmp</code>]</dt><dd><p>Runs a test of <code>brew update</code> with a new repository clone.</p>
 
 <p>If no arguments are passed, use <code>origin/master</code> as the start commit.</p>
 
-<p>If <code>--commit=&lt;sha1></code> is passed, use <code>&lt;sha1></code> as the start commit.</p>
+<p>If <code>--commit=&lt;commit></code> is passed, use <code>&lt;commit></code> as the start commit.</p>
 
 <p>If <code>--before=&lt;date></code> is passed, use the commit at <code>&lt;date></code> as the
 start commit.</p>
@@ -731,7 +731,7 @@ your shell profile, or you can use it before a brew command:</p>
 
 <p>Homebrew's current maintainers are Misty De Meo, Andrew Janke, Xu Cheng, Tomasz Pajor, Baptiste Fontaine, Zhiming Wang, Brett Koonce, ilovezfs, Martin Afanasjew, Uladzislau Shablinski, Dominyk Tiller, Tim Smith and Alex Dunn.</p>
 
-<p>Former maintainers with significant contributions include Jack Nagel, Adam Vandenberg, Max Howell and Homebrew's creator: Max Howell.</p>
+<p>Former maintainers with significant contributions include Jack Nagel, Adam Vandenberg and Homebrew's creator: Max Howell.</p>
 
 <h2 id="BUGS">BUGS</h2>
 
diff --git a/manpages/brew-cask.1 b/manpages/brew-cask.1
index dd2bc133c..b447c6285 100644
--- a/manpages/brew-cask.1
+++ b/manpages/brew-cask.1
@@ -18,11 +18,11 @@ Homebrew\-Cask works robustly enough that we welcome new users, but the project
 .SH "FREQUENTLY USED COMMANDS"
 .
 .TP
-\fBinstall [\-\-force] [\-\-skip\-cask\-deps] [\-\-require\-sha]\fR \fItoken\fR [ \fItoken\fR \.\.\. ]
+\fBinstall\fR [\-\-force] [\-\-skip\-cask\-deps] [\-\-require\-sha] \fItoken\fR [ \fItoken\fR \.\.\. ]
 Install Cask identified by \fItoken\fR\.
 .
 .TP
-\fBuninstall [\-\-force]\fR \fItoken\fR [ \fItoken\fR \.\.\. ]
+\fBuninstall\fR [\-\-force] \fItoken\fR [ \fItoken\fR \.\.\. ]
 Uninstall Cask identified by \fItoken\fR\.
 .
 .TP
@@ -74,41 +74,31 @@ With no arguments, display the project page \fIhttp://caskroom\.io\fR\.
 Display information about the given Cask\.
 .
 .TP
-\fBinstall [\-\-force] [\-\-skip\-cask\-deps] [\-\-require\-sha]\fR \fItoken\fR [ \fItoken\fR \.\.\. ]
+\fBinstall\fR [\-\-force] [\-\-skip\-cask\-deps] [\-\-require\-sha] \fItoken\fR [ \fItoken\fR \.\.\. ]
 Install the given Cask\. With \fB\-\-force\fR, re\-install even if the Cask appears to be already present\. With \fB\-\-skip\-cask\-deps\fR, skip any Cask dependencies\. \fB\-\-require\-sha\fR will abort installation if the Cask does not have a checksum defined\.
 .
 .IP
 \fItoken\fR is usually the ID of a Cask as returned by \fBbrew cask search\fR, but see \fIOTHER WAYS TO SPECIFY A CASK\fR for variations\.
 .
 .TP
-\fBlist\fR or \fBls\fR [\-1 | \-l] [ \fItoken\fR \.\.\. ]
-Without any arguments, list all installed Casks\. With \fB\-1\fR, always format the output in a single column\. With \fB\-l\fR, give a more detailed listing\.
+\fBlist\fR or \fBls\fR [\-1] [\-\-versions] [ \fItoken\fR \.\.\. ]
+Without any arguments, list all installed Casks\. With \fB\-1\fR, always format the output in a single column\. With \fB\-\-versions\fR, show all installed versions\.
 .
 .IP
 If \fItoken\fR is given, summarize the staged files associated with the given Cask\.
 .
 .TP
-\fBsearch\fR or \fB\-S\fR
-Display all Casks available for install\.
-.
-.TP
-\fBsearch\fR or \fB\-S\fR \fItext\fR | /\fIregexp\fR/
-Perform a substring search of known Cask tokens for \fItext\fR\. If the text is delimited by slashes, it is interpreted as a Ruby regular expression\.
+\fBsearch\fR or \fB\-S\fR [\fItext\fR | /\fIregexp\fR/]
+Without argument, display all Casks available for install, otherwise perform a substring search of known Cask tokens for \fItext\fR or, if the text is delimited by slashes (/\fIregexp\fR/), it is interpreted as a Ruby regular expression\.
 .
 .TP
 \fBstyle\fR [\-\-fix] [ \fItoken\fR \.\.\. ]
 Check the given Casks for correct style using RuboCop Cask \fIhttps://github\.com/caskroom/rubocop\-cask\fR\. If no tokens are given on the command line, all Casks are checked\. With \fB\-\-fix\fR, auto\-correct any style errors if possible\.
 .
 .TP
-\fBuninstall [\-\-force]\fR or \fBrm\fR or \fBremove\fR \fItoken\fR [ \fItoken\fR \.\.\. ]
+\fBuninstall\fR or \fBrm\fR or \fBremove\fR [\-\-force] \fItoken\fR [ \fItoken\fR \.\.\. ]
 Uninstall the given Cask\. With \fB\-\-force\fR, uninstall even if the Cask does not appear to be present\.
 .
-.IP
-Note that \fBuninstall \-\-force\fR is currently imperfect\. It will follow the \fBuninstall\fR instructions from \fInewest\fR Cask definition, even if the given Cask has changed since you installed it\. The result is that \fBuninstall \-\-force\fR will always succeed in removing relevant files under \fB<Caskroom_path>\fR, but will sometimes fail to remove relevant installed files outside of it\. This issue is being addressed\.
-.
-.IP
-\fBuninstall\fR without \fB\-\-force\fR is also imperfect\. It may be unable to perform an \fBuninstall\fR operation if the given Cask has changed since you installed it\. This issue is being addressed\.
-.
 .TP
 \fBupdate\fR
 For convenience\. \fBbrew cask update\fR is a synonym for \fBbrew update\fR\.
diff --git a/manpages/brew.1 b/manpages/brew.1
index c4a650335..55f150094 100644
--- a/manpages/brew.1
+++ b/manpages/brew.1
@@ -752,7 +752,7 @@ Generate the README\.md file for a new tap\.
 .
 .TP
 \fBtest\fR [\fB\-\-devel\fR|\fB\-\-HEAD\fR] [\fB\-\-debug\fR] [\fB\-\-keep\-tmp\fR] \fIformula\fR
-A few formulae provide a test method\. \fBbrew test\fR \fIformula\fR runs this test method\. There is no standard output or return code, but it should generally indicate to the user if something is wrong with the installed formula\.
+Most formulae provide a test method\. \fBbrew test\fR \fIformula\fR runs this test method\. There is no standard output or return code, but it should generally indicate to the user if something is wrong with the installed formula\.
 .
 .IP
 To test the development or head version of a formula, use \fB\-\-devel\fR or \fB\-\-HEAD\fR\.
@@ -771,14 +771,14 @@ Example: \fBbrew install jruby && brew test jruby\fR
 Run Homebrew\'s unit and integration tests\.
 .
 .TP
-\fBupdate\-test\fR [\fB\-\-commit=<sha1>\fR] [\fB\-\-before=<date>\fR] [\fB\-\-keep\-tmp\fR]
+\fBupdate\-test\fR [\fB\-\-commit=<commit>\fR] [\fB\-\-before=<date>\fR] [\fB\-\-keep\-tmp\fR]
 Runs a test of \fBbrew update\fR with a new repository clone\.
 .
 .IP
 If no arguments are passed, use \fBorigin/master\fR as the start commit\.
 .
 .IP
-If \fB\-\-commit=<sha1>\fR is passed, use \fB<sha1>\fR as the start commit\.
+If \fB\-\-commit=<commit>\fR is passed, use \fB<commit>\fR as the start commit\.
 .
 .IP
 If \fB\-\-before=<date>\fR is passed, use the commit at \fB<date>\fR as the start commit\.
@@ -1001,7 +1001,7 @@ Homebrew\'s lead maintainer is Mike McQuaid\.
 Homebrew\'s current maintainers are Misty De Meo, Andrew Janke, Xu Cheng, Tomasz Pajor, Baptiste Fontaine, Zhiming Wang, Brett Koonce, ilovezfs, Martin Afanasjew, Uladzislau Shablinski, Dominyk Tiller, Tim Smith and Alex Dunn\.
 .
 .P
-Former maintainers with significant contributions include Jack Nagel, Adam Vandenberg, Max Howell and Homebrew\'s creator: Max Howell\.
+Former maintainers with significant contributions include Jack Nagel, Adam Vandenberg and Homebrew\'s creator: Max Howell\.
 .
 .SH "BUGS"
 See our issues on GitHub:
@@ -1013,3 +1013,4 @@ Homebrew/brew \fIhttps://github\.com/Homebrew/brew/issues\fR
 Homebrew/homebrew\-core \fIhttps://github\.com/Homebrew/homebrew\-core/issues\fR
 .
 .IP "" 0
+