Cask: Use nested classes and modules.

29 files changed, 765 insertions, 649 deletions

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 c879fc2be..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 8f41e9fd5..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}'"
-    raise Hbc::CaskError, "Cannot remove undeletable #{self.class.artifact_english_name}" if MacOS.undeletable?(target)
+      def delete
+        ohai "Removing #{self.class.artifact_english_name}: '#{target}'"
+        raise CaskError, "Cannot remove undeletable #{self.class.artifact_english_name}" if MacOS.undeletable?(target)
 
-    if force
-      Hbc::Utils.gain_permissions_remove(target, command: @command)
-    else
-      target.rmtree
-    end
-  end
+        if force
+          Utils.gain_permissions_remove(target, command: @command)
+        else
+          target.rmtree
+        end
+      end
 
-  def summarize_artifact(artifact_spec)
-    load_specification artifact_spec
+      def summarize_artifact(artifact_spec)
+        load_specification artifact_spec
 
-    if target.exist?
-      target_abv = " (#{target.abv})"
-    else
-      warning = "Missing #{self.class.artifact_english_name}"
-      warning = "#{Tty.red}#{warning}#{Tty.reset}: "
-    end
+        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}"
+        "#{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