Merge branch 'master' into filter_all_env_vars_932

388 files changed, 11458 insertions, 8298 deletions

diff --git a/Library/Homebrew/test/ARGV_spec.rb b/Library/Homebrew/test/ARGV_spec.rb
new file mode 100644
index 000000000..89ef9cabc
--- /dev/null
+++ b/Library/Homebrew/test/ARGV_spec.rb
@@ -0,0 +1,149 @@
+require "extend/ARGV"
+
+describe HomebrewArgvExtension do
+  subject { argv.extend(described_class) }
+  let(:argv) { ["mxcl"] }
+
+  describe "#formulae" do
+    it "raises an error when a Formula is unavailable" do
+      expect { subject.formulae }.to raise_error FormulaUnavailableError
+    end
+
+    context "when there are no Formulae" do
+      let(:argv) { [] }
+
+      it "returns an empty array" do
+        expect(subject.formulae).to be_empty
+      end
+    end
+  end
+
+  describe "#casks" do
+    it "returns an empty array if there is no match" do
+      expect(subject.casks).to eq []
+    end
+  end
+
+  describe "#kegs" do
+    context "when there are matching Kegs" do
+      before(:each) do
+        keg = HOMEBREW_CELLAR + "mxcl/10.0"
+        keg.mkpath
+      end
+
+      it "returns an array of Kegs" do
+        expect(subject.kegs.length).to eq 1
+      end
+    end
+
+    context "when there are no matching Kegs" do
+      let(:argv) { [] }
+
+      it "returns an empty array" do
+        expect(subject.kegs).to be_empty
+      end
+    end
+  end
+
+  describe "#named" do
+    let(:argv) { ["foo", "--debug", "-v"] }
+
+    it "returns an array of non-option arguments" do
+      expect(subject.named).to eq ["foo"]
+    end
+
+    context "when there are no named arguments" do
+      let(:argv) { [] }
+
+      it "returns an empty array" do
+        expect(subject.named).to be_empty
+      end
+    end
+  end
+
+  describe "#options_only" do
+    let(:argv) { ["--foo", "-vds", "a", "b", "cdefg"] }
+
+    it "returns an array of option arguments" do
+      expect(subject.options_only).to eq ["--foo", "-vds"]
+    end
+  end
+
+  describe "#flags_only" do
+    let(:argv) { ["--foo", "-vds", "a", "b", "cdefg"] }
+
+    it "returns an array of flags" do
+      expect(subject.flags_only).to eq ["--foo"]
+    end
+  end
+
+  describe "#empty?" do
+    let(:argv) { [] }
+
+    it "returns true if it is empty" do
+      expect(subject).to be_empty
+    end
+  end
+
+  describe "#switch?" do
+    let(:argv) { ["-ns", "-i", "--bar", "-a-bad-arg"] }
+
+    it "returns true if the given string is a switch" do
+      %w[n s i].each do |s|
+        expect(subject.switch?(s)).to be true
+      end
+    end
+
+    it "returns false if the given string is not a switch" do
+      %w[b ns bar --bar -n a bad arg].each do |s|
+        expect(subject.switch?(s)).to be false
+      end
+    end
+  end
+
+  describe "#flag?" do
+    let(:argv) { ["--foo", "-bq", "--bar"] }
+
+    it "returns true if the given string is a flag" do
+      expect(subject.flag?("--foo")).to eq true
+      expect(subject.flag?("--bar")).to eq true
+    end
+
+    it "returns true if there is a switch with the same initial character" do
+      expect(subject.flag?("--baz")).to eq true
+      expect(subject.flag?("--qux")).to eq true
+    end
+
+    it "returns false if there is no matching flag" do
+      expect(subject.flag?("--frotz")).to eq false
+      expect(subject.flag?("--debug")).to eq false
+    end
+  end
+
+  describe "#value" do
+    let(:argv) { ["--foo=", "--bar=ab"] }
+
+    it "returns the value for a given string" do
+      expect(subject.value("foo")).to eq ""
+      expect(subject.value("bar")).to eq "ab"
+    end
+
+    it "returns nil if there is no matching argument" do
+      expect(subject.value("baz")).to be nil
+    end
+  end
+
+  describe "#values" do
+    let(:argv) { ["--foo=", "--bar=a", "--baz=b,c"] }
+
+    it "returns the value for a given argument" do
+      expect(subject.values("foo")).to eq []
+      expect(subject.values("bar")).to eq ["a"]
+      expect(subject.values("baz")).to eq ["b", "c"]
+    end
+
+    it "returns nil if there is no matching argument" do
+      expect(subject.values("qux")).to be nil
+    end
+  end
+end
diff --git a/Library/Homebrew/test/ARGV_test.rb b/Library/Homebrew/test/ARGV_test.rb
deleted file mode 100644
index 6805e0c62..000000000
--- a/Library/Homebrew/test/ARGV_test.rb
+++ /dev/null
@@ -1,80 +0,0 @@
-require "testing_env"
-require "extend/ARGV"
-
-class ArgvExtensionTests < Homebrew::TestCase
-  def setup
-    @argv = [].extend(HomebrewArgvExtension)
-  end
-
-  def test_argv_formulae
-    @argv.unshift "mxcl"
-    assert_raises(FormulaUnavailableError) { @argv.formulae }
-  end
-
-  def test_argv_casks
-    @argv.unshift "mxcl"
-    assert_equal [], @argv.casks
-  end
-
-  def test_argv_kegs
-    keg = HOMEBREW_CELLAR + "mxcl/10.0"
-    keg.mkpath
-    @argv << "mxcl"
-    assert_equal 1, @argv.kegs.length
-  ensure
-    keg.parent.rmtree
-  end
-
-  def test_argv_named
-    @argv << "foo" << "--debug" << "-v"
-    assert_equal %w[foo], @argv.named
-  end
-
-  def test_options_only
-    @argv << "--foo" << "-vds" << "a" << "b" << "cdefg"
-    assert_equal %w[--foo -vds], @argv.options_only
-  end
-
-  def test_flags_only
-    @argv << "--foo" << "-vds" << "a" << "b" << "cdefg"
-    assert_equal %w[--foo], @argv.flags_only
-  end
-
-  def test_empty_argv
-    assert_empty @argv.named
-    assert_empty @argv.kegs
-    assert_empty @argv.formulae
-    assert_empty @argv
-  end
-
-  def test_switch?
-    @argv << "-ns" << "-i" << "--bar" << "-a-bad-arg"
-    %w[n s i].each { |s| assert @argv.switch?(s) }
-    %w[b ns bar --bar -n a bad arg].each { |s| assert !@argv.switch?(s) }
-  end
-
-  def test_flag?
-    @argv << "--foo" << "-bq" << "--bar"
-    assert @argv.flag?("--foo")
-    assert @argv.flag?("--bar")
-    assert @argv.flag?("--baz")
-    assert @argv.flag?("--qux")
-    assert !@argv.flag?("--frotz")
-    assert !@argv.flag?("--debug")
-  end
-
-  def test_value
-    @argv << "--foo=" << "--bar=ab"
-    assert_equal "", @argv.value("foo")
-    assert_equal "ab", @argv.value("bar")
-    assert_nil @argv.value("baz")
-  end
-
-  def test_values
-    @argv << "--foo=" << "--bar=a" << "--baz=b,c"
-    assert_equal [], @argv.values("foo")
-    assert_equal ["a"], @argv.values("bar")
-    assert_equal ["b", "c"], @argv.values("baz")
-    assert_nil @argv.values("qux")
-  end
-end
diff --git a/Library/Homebrew/test/ENV_spec.rb b/Library/Homebrew/test/ENV_spec.rb
new file mode 100644
index 000000000..7b50ca1d4
--- /dev/null
+++ b/Library/Homebrew/test/ENV_spec.rb
@@ -0,0 +1,189 @@
+require "extend/ENV"
+
+shared_examples EnvActivation do
+  subject { env.extend(described_class) }
+  let(:env) { {}.extend(EnvActivation) }
+
+  it "supports switching compilers" do
+    subject.clang
+    expect(subject["LD"]).to be nil
+    expect(subject["CC"]).to eq(subject["OBJC"])
+  end
+
+  describe "#with_build_environment" do
+    it "restores the environment" do
+      before = subject.dup
+
+      subject.with_build_environment do
+        subject["foo"] = "bar"
+      end
+
+      expect(subject["foo"]).to be nil
+      expect(subject).to eq(before)
+    end
+
+    it "ensures the environment is restored" do
+      before = subject.dup
+
+      expect {
+        subject.with_build_environment do
+          subject["foo"] = "bar"
+          raise StandardError
+        end
+      }.to raise_error(StandardError)
+
+      expect(subject["foo"]).to be nil
+      expect(subject).to eq(before)
+    end
+
+    it "returns the value of the block" do
+      expect(subject.with_build_environment { 1 }).to eq(1)
+    end
+
+    it "does not mutate the interface" do
+      expected = subject.methods
+
+      subject.with_build_environment do
+        expect(subject.methods).to eq(expected)
+      end
+
+      expect(subject.methods).to eq(expected)
+    end
+  end
+
+  describe "#append" do
+    it "appends to an existing key" do
+      subject["foo"] = "bar"
+      subject.append "foo", "1"
+      expect(subject["foo"]).to eq("bar 1")
+    end
+
+    it "appends to an existing empty key" do
+      subject["foo"] = ""
+      subject.append "foo", "1"
+      expect(subject["foo"]).to eq("1")
+    end
+
+    it "appends to a non-existant key" do
+      subject.append "foo", "1"
+      expect(subject["foo"]).to eq("1")
+    end
+
+    # NOTE: this may be a wrong behavior; we should probably reject objects that
+    # do not respond to #to_str. For now this documents existing behavior.
+    it "coerces a value to a string" do
+      subject.append "foo", 42
+      expect(subject["foo"]).to eq("42")
+    end
+  end
+
+  describe "#prepend" do
+    it "prepends to an existing key" do
+      subject["foo"] = "bar"
+      subject.prepend "foo", "1"
+      expect(subject["foo"]).to eq("1 bar")
+    end
+
+    it "prepends to an existing empty key" do
+      subject["foo"] = ""
+      subject.prepend "foo", "1"
+      expect(subject["foo"]).to eq("1")
+    end
+
+    it "prepends to a non-existant key" do
+      subject.prepend "foo", "1"
+      expect(subject["foo"]).to eq("1")
+    end
+
+    # NOTE: this may be a wrong behavior; we should probably reject objects that
+    # do not respond to #to_str. For now this documents existing behavior.
+    it "coerces a value to a string" do
+      subject.prepend "foo", 42
+      expect(subject["foo"]).to eq("42")
+    end
+  end
+
+  describe "#append_path" do
+    it "appends to a path" do
+      subject.append_path "FOO", "/usr/bin"
+      expect(subject["FOO"]).to eq("/usr/bin")
+
+      subject.append_path "FOO", "/bin"
+      expect(subject["FOO"]).to eq("/usr/bin#{File::PATH_SEPARATOR}/bin")
+    end
+  end
+
+  describe "#prepend_path" do
+    it "prepends to a path" do
+      subject.prepend_path "FOO", "/usr/bin"
+      expect(subject["FOO"]).to eq("/usr/bin")
+
+      subject.prepend_path "FOO", "/bin"
+      expect(subject["FOO"]).to eq("/bin#{File::PATH_SEPARATOR}/usr/bin")
+    end
+  end
+
+  describe "#compiler" do
+    it "allows switching compilers" do
+      [:clang, :gcc_4_2, :gcc_4_0].each do |compiler|
+        subject.public_send(compiler)
+        expect(subject.compiler).to eq(compiler)
+      end
+    end
+  end
+
+  example "deparallelize_block_form_restores_makeflags" do
+    subject["MAKEFLAGS"] = "-j4"
+
+    subject.deparallelize do
+      expect(subject["MAKEFLAGS"]).to be nil
+    end
+
+    expect(subject["MAKEFLAGS"]).to eq("-j4")
+  end
+end
+
+describe Stdenv do
+  include_examples EnvActivation
+end
+
+describe Superenv do
+  include_examples EnvActivation
+
+  it "initializes deps" do
+    expect(subject.deps).to eq([])
+    expect(subject.keg_only_deps).to eq([])
+  end
+
+  describe "#cxx11" do
+    it "raises an error when the compiler isn't supported" do
+      %w[gcc gcc-4.7].each do |compiler|
+        subject["HOMEBREW_CC"] = compiler
+
+        expect { subject.cxx11 }
+          .to raise_error(/The selected compiler doesn't support C\+\+11:/)
+
+        expect(subject["HOMEBREW_CCCFG"]).to be nil
+      end
+    end
+
+    it "supports gcc-5" do
+      subject["HOMEBREW_CC"] = "gcc-5"
+      subject.cxx11
+      expect(subject["HOMEBREW_CCCFG"]).to include("x")
+    end
+
+    example "supports gcc-6" do
+      subject["HOMEBREW_CC"] = "gcc-6"
+      subject.cxx11
+      expect(subject["HOMEBREW_CCCFG"]).to include("x")
+    end
+
+    it "supports clang" do
+      subject["HOMEBREW_CC"] = "clang"
+      subject.cxx11
+      expect(subject["HOMEBREW_CCCFG"]).to include("x")
+      expect(subject["HOMEBREW_CCCFG"]).to include("g")
+    end
+  end
+end
diff --git a/Library/Homebrew/test/ENV_test.rb b/Library/Homebrew/test/ENV_test.rb
deleted file mode 100644
index dd6025084..000000000
--- a/Library/Homebrew/test/ENV_test.rb
+++ /dev/null
@@ -1,201 +0,0 @@
-require "testing_env"
-require "extend/ENV"
-require "testing_env"
-
-class IntegrationCommandTestEnv < IntegrationCommandTestCase
-  def test_env
-    assert_match(/CMAKE_PREFIX_PATH="#{Regexp.escape(HOMEBREW_PREFIX)}[:"]/,
-                 cmd("--env"))
-  end
-
-  def test_env_fish
-    assert_match(/set [-]gx CMAKE_PREFIX_PATH "#{Regexp.quote(HOMEBREW_PREFIX.to_s)}"/,
-                 cmd("--env", "--shell=fish"))
-  end
-
-  def test_env_csh
-    assert_match(/setenv CMAKE_PREFIX_PATH #{Regexp.quote(HOMEBREW_PREFIX.to_s)};/,
-                 cmd("--env", "--shell=tcsh"))
-  end
-
-  def test_env_bash
-    assert_match(/export CMAKE_PREFIX_PATH="#{Regexp.quote(HOMEBREW_PREFIX.to_s)}"/,
-                 cmd("--env", "--shell=bash"))
-  end
-
-  def test_env_plain
-    assert_match(/CMAKE_PREFIX_PATH: #{Regexp.quote(HOMEBREW_PREFIX)}/,
-                 cmd("--env", "--plain"))
-  end
-end
-
-module SharedEnvTests
-  def setup
-    @env = {}.extend(EnvActivation)
-  end
-
-  def test_switching_compilers
-    @env.clang
-    assert_nil @env["LD"]
-    assert_equal @env["OBJC"], @env["CC"]
-  end
-
-  def test_with_build_environment_restores_env
-    before = @env.dup
-    @env.with_build_environment do
-      @env["foo"] = "bar"
-    end
-    assert_nil @env["foo"]
-    assert_equal before, @env
-  end
-
-  def test_with_build_environment_ensures_env_restored
-    before = @env.dup
-    begin
-      @env.with_build_environment do
-        @env["foo"] = "bar"
-        raise Exception
-      end
-    rescue Exception
-    end
-    assert_nil @env["foo"]
-    assert_equal before, @env
-  end
-
-  def test_with_build_environment_returns_block_value
-    assert_equal 1, @env.with_build_environment { 1 }
-  end
-
-  def test_with_build_environment_does_not_mutate_interface
-    expected = @env.methods
-    @env.with_build_environment { assert_equal expected, @env.methods }
-    assert_equal expected, @env.methods
-  end
-
-  def test_append_existing_key
-    @env["foo"] = "bar"
-    @env.append "foo", "1"
-    assert_equal "bar 1", @env["foo"]
-  end
-
-  def test_append_existing_key_empty
-    @env["foo"] = ""
-    @env.append "foo", "1"
-    assert_equal "1", @env["foo"]
-  end
-
-  def test_append_missing_key
-    @env.append "foo", "1"
-    assert_equal "1", @env["foo"]
-  end
-
-  def test_prepend_existing_key
-    @env["foo"] = "bar"
-    @env.prepend "foo", "1"
-    assert_equal "1 bar", @env["foo"]
-  end
-
-  def test_prepend_existing_key_empty
-    @env["foo"] = ""
-    @env.prepend "foo", "1"
-    assert_equal "1", @env["foo"]
-  end
-
-  def test_prepend_missing_key
-    @env.prepend "foo", "1"
-    assert_equal "1", @env["foo"]
-  end
-
-  # NOTE: this may be a wrong behavior; we should probably reject objects that
-  # do not respond to #to_str. For now this documents existing behavior.
-  def test_append_coerces_value_to_string
-    @env.append "foo", 42
-    assert_equal "42", @env["foo"]
-  end
-
-  def test_prepend_coerces_value_to_string
-    @env.prepend "foo", 42
-    assert_equal "42", @env["foo"]
-  end
-
-  def test_append_path
-    @env.append_path "FOO", "/usr/bin"
-    assert_equal "/usr/bin", @env["FOO"]
-    @env.append_path "FOO", "/bin"
-    assert_equal "/usr/bin#{File::PATH_SEPARATOR}/bin", @env["FOO"]
-  end
-
-  def test_prepend_path
-    @env.prepend_path "FOO", "/usr/bin"
-    assert_equal "/usr/bin", @env["FOO"]
-    @env.prepend_path "FOO", "/bin"
-    assert_equal "/bin#{File::PATH_SEPARATOR}/usr/bin", @env["FOO"]
-  end
-
-  def test_switching_compilers_updates_compiler
-    [:clang, :gcc_4_2, :gcc_4_0].each do |compiler|
-      @env.send(compiler)
-      assert_equal compiler, @env.compiler
-    end
-  end
-
-  def test_deparallelize_block_form_restores_makeflags
-    @env["MAKEFLAGS"] = "-j4"
-    @env.deparallelize do
-      assert_nil @env["MAKEFLAGS"]
-    end
-    assert_equal "-j4", @env["MAKEFLAGS"]
-  end
-end
-
-class StdenvTests < Homebrew::TestCase
-  include SharedEnvTests
-
-  def setup
-    super
-    @env.extend(Stdenv)
-  end
-end
-
-class SuperenvTests < Homebrew::TestCase
-  include SharedEnvTests
-
-  def setup
-    super
-    @env.extend(Superenv)
-  end
-
-  def test_initializes_deps
-    assert_equal [], @env.deps
-    assert_equal [], @env.keg_only_deps
-  end
-
-  def test_unsupported_cxx11
-    %w[gcc gcc-4.7].each do |compiler|
-      @env["HOMEBREW_CC"] = compiler
-      assert_raises do
-        @env.cxx11
-      end
-      refute_match "x", @env["HOMEBREW_CCCFG"]
-    end
-  end
-
-  def test_supported_cxx11_gcc_5
-    @env["HOMEBREW_CC"] = "gcc-5"
-    @env.cxx11
-    assert_match "x", @env["HOMEBREW_CCCFG"]
-  end
-
-  def test_supported_cxx11_gcc_6
-    @env["HOMEBREW_CC"] = "gcc-6"
-    @env.cxx11
-    assert_match "x", @env["HOMEBREW_CCCFG"]
-  end
-
-  def test_supported_cxx11_clang
-    @env["HOMEBREW_CC"] = "clang"
-    @env.cxx11
-    assert_match "x", @env["HOMEBREW_CCCFG"]
-    assert_match "g", @env["HOMEBREW_CCCFG"]
-  end
-end
diff --git a/Library/Homebrew/test/Gemfile b/Library/Homebrew/test/Gemfile
index a7e9eb834..25c8ce7ec 100644
--- a/Library/Homebrew/test/Gemfile
+++ b/Library/Homebrew/test/Gemfile
@@ -1,20 +1,14 @@
 source "https://rubygems.org"
 
-gem "mocha", "~> 1.1"
-gem "minitest", "~> 5.3"
-gem "rake", "~> 10.3"
-gem "parallel_tests", "~> 2.9"
+gem "mocha"
+gem "minitest"
+gem "minitest-reporters"
+gem "parallel_tests"
+gem "rspec"
+gem "rspec-its", require: false
+gem "rspec-wait", require: false
 
 group :coverage 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",
-    ref: "83d8031ddde0927f87ef9327200a98583ca18d77",
-    require: false
+  gem "simplecov", require: false
   gem "codecov", require: false
 end
diff --git a/Library/Homebrew/test/Gemfile.lock b/Library/Homebrew/test/Gemfile.lock
index aa4800f34..fba45d77b 100644
--- a/Library/Homebrew/test/Gemfile.lock
+++ b/Library/Homebrew/test/Gemfile.lock
@@ -1,31 +1,50 @@
-GIT
-  remote: https://github.com/colszowka/simplecov.git
-  revision: 83d8031ddde0927f87ef9327200a98583ca18d77
-  ref: 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:
-    codecov (0.1.6)
+    ansi (1.5.0)
+    builder (3.2.3)
+    codecov (0.1.9)
       json
       simplecov
       url
+    diff-lcs (1.3)
     docile (1.1.5)
-    json (2.0.2)
+    json (2.0.3)
     metaclass (0.0.4)
-    minitest (5.9.1)
+    minitest (5.10.1)
+    minitest-reporters (1.1.14)
+      ansi
+      builder
+      minitest (>= 5.0)
+      ruby-progressbar
     mocha (1.2.1)
       metaclass (~> 0.0.1)
-    parallel (1.9.0)
-    parallel_tests (2.10.0)
+    parallel (1.10.0)
+    parallel_tests (2.13.0)
       parallel
-    rake (10.5.0)
+    rspec (3.5.0)
+      rspec-core (~> 3.5.0)
+      rspec-expectations (~> 3.5.0)
+      rspec-mocks (~> 3.5.0)
+    rspec-core (3.5.4)
+      rspec-support (~> 3.5.0)
+    rspec-expectations (3.5.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.5.0)
+    rspec-its (1.2.0)
+      rspec-core (>= 3.0.0)
+      rspec-expectations (>= 3.0.0)
+    rspec-mocks (3.5.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.5.0)
+    rspec-support (3.5.0)
+    rspec-wait (0.0.9)
+      rspec (>= 3, < 4)
+    ruby-progressbar (1.8.1)
+    simplecov (0.13.0)
+      docile (~> 1.1.0)
+      json (>= 1.8, < 3)
+      simplecov-html (~> 0.10.0)
     simplecov-html (0.10.0)
     url (0.3.2)
 
@@ -34,11 +53,14 @@ PLATFORMS
 
 DEPENDENCIES
   codecov
-  minitest (~> 5.3)
-  mocha (~> 1.1)
-  parallel_tests (~> 2.9)
-  rake (~> 10.3)
-  simplecov (= 0.12.0)!
+  minitest
+  minitest-reporters
+  mocha
+  parallel_tests
+  rspec
+  rspec-its
+  rspec-wait
+  simplecov
 
 BUNDLED WITH
-   1.13.6
+   1.14.3
diff --git a/Library/Homebrew/test/analytics_test.rb b/Library/Homebrew/test/analytics_test.rb
deleted file mode 100644
index 37040f3cd..000000000
--- a/Library/Homebrew/test/analytics_test.rb
+++ /dev/null
@@ -1,26 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestAnalytics < IntegrationCommandTestCase
-  def test_analytics
-    HOMEBREW_REPOSITORY.cd do
-      shutup do
-        system "git", "init"
-      end
-    end
-
-    assert_match "Analytics is disabled (by HOMEBREW_NO_ANALYTICS)",
-      cmd("analytics", "HOMEBREW_NO_ANALYTICS" => "1")
-
-    cmd("analytics", "off")
-    assert_match "Analytics is disabled",
-      cmd("analytics", "HOMEBREW_NO_ANALYTICS" => nil)
-
-    cmd("analytics", "on")
-    assert_match "Analytics is enabled", cmd("analytics",
-      "HOMEBREW_NO_ANALYTICS" => nil)
-
-    assert_match "Invalid usage", cmd_fail("analytics", "on", "off")
-    assert_match "Invalid usage", cmd_fail("analytics", "testball")
-    cmd("analytics", "regenerate-uuid")
-  end
-end
diff --git a/Library/Homebrew/test/audit_test.rb b/Library/Homebrew/test/audit_test.rb
index dace4dc2b..f4b7cae4a 100644
--- a/Library/Homebrew/test/audit_test.rb
+++ b/Library/Homebrew/test/audit_test.rb
@@ -6,13 +6,10 @@ require "dev-cmd/audit"
 
 class FormulaTextTests < Homebrew::TestCase
   def setup
+    super
     @dir = mktmpdir
   end
 
-  def teardown
-    FileUtils.rm_rf @dir
-  end
-
   def formula_text(name, body = nil, options = {})
     path = Pathname.new "#{@dir}/#{name}.rb"
     path.open("w") do |f|
@@ -58,13 +55,10 @@ end
 
 class FormulaAuditorTests < Homebrew::TestCase
   def setup
+    super
     @dir = mktmpdir
   end
 
-  def teardown
-    FileUtils.rm_rf @dir
-  end
-
   def formula_auditor(name, text, options = {})
     path = Pathname.new "#{@dir}/#{name}.rb"
     path.open("w") do |f|
@@ -249,7 +243,7 @@ class FormulaAuditorTests < Homebrew::TestCase
     needs_compat
     require "compat/formula_specialties"
 
-    ARGV.stubs(:homebrew_developer?).returns false
+    ENV.delete("HOMEBREW_DEVELOPER")
     fa = shutup do
       formula_auditor "foo", <<-EOS.undent
         class Foo < GithubGistFormula
@@ -266,7 +260,7 @@ class FormulaAuditorTests < Homebrew::TestCase
     needs_compat
     require "compat/formula_specialties"
 
-    ARGV.stubs(:homebrew_developer?).returns false
+    ENV.delete("HOMEBREW_DEVELOPER")
     fa = formula_auditor "foo", <<-EOS.undent
       class Foo < ScriptFileFormula
         url "http://example.com/foo-1.0.tgz"
@@ -281,7 +275,7 @@ class FormulaAuditorTests < Homebrew::TestCase
     needs_compat
     require "compat/formula_specialties"
 
-    ARGV.stubs(:homebrew_developer?).returns false
+    ENV.delete("HOMEBREW_DEVELOPER")
     fa = formula_auditor "foo", <<-EOS.undent
       class Foo < AmazonWebServicesFormula
         url "http://example.com/foo-1.0.tgz"
@@ -367,13 +361,10 @@ class FormulaAuditorTests < Homebrew::TestCase
       end
     EOS
 
-    original_value = ENV["HOMEBREW_NO_GITHUB_API"]
     ENV["HOMEBREW_NO_GITHUB_API"] = "1"
 
     fa.audit_github_repository
     assert_equal [], fa.problems
-  ensure
-    ENV["HOMEBREW_NO_GITHUB_API"] = original_value
   end
 
   def test_audit_caveats
@@ -428,9 +419,8 @@ class FormulaAuditorTests < Homebrew::TestCase
     EOS
 
     fa.audit_homepage
-    assert_equal ["The homepage should start with http or https " \
-      "(URL is #{fa.formula.homepage}).", "The homepage #{fa.formula.homepage} is not reachable " \
-      "(HTTP status code 000)"], fa.problems
+    assert_equal ["The homepage should start with http or https (URL is #{fa.formula.homepage})."],
+      fa.problems
 
     formula_homepages = {
       "bar" => "http://www.freedesktop.org/wiki/bar",
@@ -440,6 +430,10 @@ class FormulaAuditorTests < Homebrew::TestCase
       "corge" => "http://savannah.nongnu.org/corge",
       "grault" => "http://grault.github.io/",
       "garply" => "http://www.gnome.org/garply",
+      "sf1" => "http://foo.sourceforge.net/",
+      "sf2" => "http://foo.sourceforge.net",
+      "sf3" => "http://foo.sf.net/",
+      "sf4" => "http://foo.sourceforge.io/",
       "waldo" => "http://www.gnu.org/waldo",
     }
 
@@ -464,9 +458,45 @@ class FormulaAuditorTests < Homebrew::TestCase
         end
       elsif homepage =~ %r{https:\/\/code\.google\.com}
         assert_match "#{homepage} should end with a slash", fa.problems.first
+      elsif homepage =~ /foo\.(sf|sourceforge)\.net/
+        assert_match "#{homepage} should be `https://foo.sourceforge.io/`", fa.problems.first
       else
         assert_match "Please use https:// for #{homepage}", fa.problems.first
       end
     end
   end
+
+  def test_audit_xcodebuild_suggests_symroot
+    fa = formula_auditor "foo", <<-EOS.undent
+      class Foo < Formula
+        url "http://example.com/foo-1.0.tgz"
+        homepage "http://example.com"
+
+        def install
+          xcodebuild "-project", "meow.xcodeproject"
+        end
+      end
+    EOS
+
+    fa.audit_text
+
+    assert_match 'xcodebuild should be passed an explicit "SYMROOT"', fa.problems.first
+  end
+
+  def test_audit_bare_xcodebuild_suggests_symroot_also
+    fa = formula_auditor "foo", <<-EOS.undent
+      class Foo < Formula
+        url "http://example.com/foo-1.0.tgz"
+        homepage "http://example.com"
+
+        def install
+          xcodebuild
+        end
+      end
+    EOS
+
+    fa.audit_text
+
+    assert_match 'xcodebuild should be passed an explicit "SYMROOT"', fa.problems.first
+  end
 end
diff --git a/Library/Homebrew/test/bash_spec.rb b/Library/Homebrew/test/bash_spec.rb
new file mode 100644
index 000000000..1b0f15066
--- /dev/null
+++ b/Library/Homebrew/test/bash_spec.rb
@@ -0,0 +1,52 @@
+require "open3"
+
+RSpec::Matchers.define :have_valid_bash_syntax do
+  match do |file|
+    stdout, stderr, status = Open3.capture3("/bin/bash", "-n", file)
+
+    @actual = [file, stderr]
+
+    stdout.empty? && status.success?
+  end
+
+  failure_message do |(file, stderr)|
+    "expected that #{file} is a valid Bash file:\n#{stderr}"
+  end
+end
+
+describe "Bash" do
+  context "brew" do
+    subject { HOMEBREW_LIBRARY_PATH.parent.parent/"bin/brew" }
+    it { is_expected.to have_valid_bash_syntax }
+  end
+
+  context "every `.sh` file" do
+    it "has valid bash syntax" do
+      Pathname.glob("#{HOMEBREW_LIBRARY_PATH}/**/*.sh").each do |path|
+        relative_path = path.relative_path_from(HOMEBREW_LIBRARY_PATH)
+        next if relative_path.to_s.start_with?("shims/", "test/", "vendor/")
+
+        expect(path).to have_valid_bash_syntax
+      end
+    end
+  end
+
+  context "Bash completion" do
+    subject { HOMEBREW_LIBRARY_PATH.parent.parent/"completions/bash/brew" }
+    it { is_expected.to have_valid_bash_syntax }
+  end
+
+  context "every shim script" do
+    it "has valid bash syntax" do
+      # These have no file extension, but can be identified by their shebang.
+      (HOMEBREW_LIBRARY_PATH/"shims").find do |path|
+        next if path.directory?
+        next if path.symlink?
+        next unless path.executable?
+        next unless path.read(12) == "#!/bin/bash\n"
+
+        expect(path).to have_valid_bash_syntax
+      end
+    end
+  end
+end
diff --git a/Library/Homebrew/test/bash_test.rb b/Library/Homebrew/test/bash_test.rb
deleted file mode 100644
index 671ab5ec8..000000000
--- a/Library/Homebrew/test/bash_test.rb
+++ /dev/null
@@ -1,35 +0,0 @@
-require "testing_env"
-
-class BashTests < Homebrew::TestCase
-  def assert_valid_bash_syntax(file)
-    return unless file.exist?
-    output = Utils.popen_read("/bin/bash -n #{file} 2>&1")
-    assert $?.success?, output
-  end
-
-  def test_bin_brew
-    assert_valid_bash_syntax HOMEBREW_LIBRARY_PATH.parent.parent/"bin/brew"
-  end
-
-  def test_bash_code
-    Pathname.glob("#{HOMEBREW_LIBRARY_PATH}/**/*.sh").each do |pn|
-      pn_relative = pn.relative_path_from(HOMEBREW_LIBRARY_PATH)
-      next if pn_relative.to_s.start_with?("shims/", "test/", "vendor/")
-      assert_valid_bash_syntax pn
-    end
-  end
-
-  def test_bash_completion
-    script = HOMEBREW_LIBRARY_PATH.parent.parent/"completions/bash/brew"
-    assert_valid_bash_syntax script
-  end
-
-  def test_bash_shims
-    # These have no file extension, but can be identified by their shebang.
-    (HOMEBREW_LIBRARY_PATH/"shims").find do |pn|
-      next if pn.directory? || pn.symlink?
-      next unless pn.executable? && pn.read(12) == "#!/bin/bash\n"
-      assert_valid_bash_syntax pn
-    end
-  end
-end
diff --git a/Library/Homebrew/test/blacklist_spec.rb b/Library/Homebrew/test/blacklist_spec.rb
new file mode 100644
index 000000000..01882167d
--- /dev/null
+++ b/Library/Homebrew/test/blacklist_spec.rb
@@ -0,0 +1,115 @@
+require "blacklist"
+
+describe "Blacklist" do
+  matcher(:be_blacklisted) { match(&method(:blacklisted?)) }
+
+  context "rubygems" do
+    %w[gem rubygem rubygems].each do |s|
+      subject { s }
+
+      it { is_expected.to be_blacklisted }
+    end
+  end
+
+  context "latex" do
+    %w[latex tex tex-live texlive TexLive].each do |s|
+      subject { s }
+
+      it { is_expected.to be_blacklisted }
+    end
+  end
+
+  context "pip" do
+    subject { "pip" }
+
+    it { is_expected.to be_blacklisted }
+  end
+
+  context "pil" do
+    subject { "pil" }
+
+    it { is_expected.to be_blacklisted }
+  end
+
+  context "macruby" do
+    subject { "MacRuby" }
+
+    it { is_expected.to be_blacklisted }
+  end
+
+  context "lzma" do
+    %w[lzma liblzma].each do |s|
+      subject { s }
+
+      it { is_expected.to be_blacklisted }
+    end
+  end
+
+  context "gtest" do
+    %w[gtest googletest google-test].each do |s|
+      subject { s }
+
+      it { is_expected.to be_blacklisted }
+    end
+  end
+
+  context "gmock" do
+    %w[gmock googlemock google-mock].each do |s|
+      subject { s }
+
+      it { is_expected.to be_blacklisted }
+    end
+  end
+
+  context "sshpass" do
+    subject { "sshpass" }
+
+    it { is_expected.to be_blacklisted }
+  end
+
+  context "gsutil" do
+    subject { "gsutil" }
+
+    it { is_expected.to be_blacklisted }
+  end
+
+  context "clojure" do
+    subject { "clojure" }
+
+    it { is_expected.to be_blacklisted }
+  end
+
+  context "osmium" do
+    %w[osmium Osmium].each do |s|
+      subject { s }
+
+      it { is_expected.to be_blacklisted }
+    end
+  end
+
+  context "gfortran" do
+    subject { "gfortran" }
+
+    it { is_expected.to be_blacklisted }
+  end
+
+  context "play" do
+    subject { "play" }
+
+    it { is_expected.to be_blacklisted }
+  end
+
+  context "haskell-platform" do
+    subject { "haskell-platform" }
+
+    it { is_expected.to be_blacklisted }
+  end
+
+  context "xcode", :needs_macos do
+    %w[xcode Xcode].each do |s|
+      subject { s }
+
+      it { is_expected.to be_blacklisted }
+    end
+  end
+end
diff --git a/Library/Homebrew/test/blacklist_test.rb b/Library/Homebrew/test/blacklist_test.rb
deleted file mode 100644
index 585a35484..000000000
--- a/Library/Homebrew/test/blacklist_test.rb
+++ /dev/null
@@ -1,68 +0,0 @@
-require "testing_env"
-require "blacklist"
-
-class BlacklistTests < Homebrew::TestCase
-  def assert_blacklisted(s)
-    assert blacklisted?(s), "'#{s}' should be blacklisted"
-  end
-
-  def test_rubygems
-    %w[gem rubygem rubygems].each { |s| assert_blacklisted s }
-  end
-
-  def test_latex
-    %w[latex tex tex-live texlive TexLive].each { |s| assert_blacklisted s }
-  end
-
-  def test_pip
-    assert_blacklisted "pip"
-  end
-
-  def test_pil
-    assert_blacklisted "pil"
-  end
-
-  def test_macruby
-    assert_blacklisted "MacRuby"
-  end
-
-  def test_lzma
-    %w[lzma liblzma].each { |s| assert_blacklisted s }
-  end
-
-  def test_gtest
-    %w[gtest googletest google-test].each { |s| assert_blacklisted s }
-  end
-
-  def test_gmock
-    %w[gmock googlemock google-mock].each { |s| assert_blacklisted s }
-  end
-
-  def test_sshpass
-    assert_blacklisted "sshpass"
-  end
-
-  def test_gsutil
-    assert_blacklisted "gsutil"
-  end
-
-  def test_clojure
-    assert_blacklisted "clojure"
-  end
-
-  def test_osmium
-    %w[osmium Osmium].each { |s| assert_blacklisted s }
-  end
-
-  def test_gfortran
-    assert_blacklisted "gfortran"
-  end
-
-  def test_play
-    assert_blacklisted "play"
-  end
-
-  def test_haskell_platform
-    assert_blacklisted "haskell-platform"
-  end
-end
diff --git a/Library/Homebrew/test/bottle_collector_test.rb b/Library/Homebrew/test/bottle_collector_test.rb
deleted file mode 100644
index d75e29ec8..000000000
--- a/Library/Homebrew/test/bottle_collector_test.rb
+++ /dev/null
@@ -1,38 +0,0 @@
-require "testing_env"
-require "utils/bottles"
-
-class BottleCollectorTests < Homebrew::TestCase
-  def setup
-    @collector = Utils::Bottles::Collector.new
-  end
-
-  def checksum_for(tag)
-    @collector.fetch_checksum_for(tag)
-  end
-
-  def test_collector_returns_passed_tags
-    @collector[:lion] = "foo"
-    @collector[:mountain_lion] = "bar"
-    assert_equal ["bar", :mountain_lion], checksum_for(:mountain_lion)
-  end
-
-  def test_collector_returns_when_empty
-    assert_nil checksum_for(:foo)
-  end
-
-  def test_collector_returns_nil_for_no_match
-    @collector[:lion] = "foo"
-    assert_nil checksum_for(:foo)
-  end
-
-  def test_collector_returns_nil_for_no_match_when_later_tag_present
-    @collector[:lion_or_later] = "foo"
-    assert_nil checksum_for(:foo)
-  end
-
-  def test_collector_prefers_exact_matches
-    @collector[:lion_or_later] = "foo"
-    @collector[:mountain_lion] = "bar"
-    assert_equal ["bar", :mountain_lion], checksum_for(:mountain_lion)
-  end
-end
diff --git a/Library/Homebrew/test/bottle_hooks_spec.rb b/Library/Homebrew/test/bottle_hooks_spec.rb
new file mode 100644
index 000000000..05c6ea7f0
--- /dev/null
+++ b/Library/Homebrew/test/bottle_hooks_spec.rb
@@ -0,0 +1,50 @@
+require "formula_installer"
+require "hooks/bottles"
+
+RSpec::Matchers.alias_matcher :pour_bottle, :be_pour_bottle
+
+describe Homebrew::Hooks::Bottles do
+  subject { FormulaInstaller.new formula }
+
+  let(:formula) do
+    double(
+      bottle: nil,
+      local_bottle_path: nil,
+      bottle_disabled?: false,
+      some_random_method: true,
+    )
+  end
+
+  after(:each) do
+    described_class.reset_hooks
+  end
+
+  describe "#setup_formula_has_bottle" do
+    context "given a block which evaluates to true" do
+      before(:each) do
+        described_class.setup_formula_has_bottle(&:some_random_method)
+      end
+
+      it { is_expected.to pour_bottle }
+    end
+
+    context "given a block which evaluates to false" do
+      before(:each) do
+        described_class.setup_formula_has_bottle { |f| !f.some_random_method }
+      end
+
+      it { is_expected.not_to pour_bottle }
+    end
+  end
+
+  describe "#setup_pour_formula_bottle" do
+    before(:each) do
+      described_class.setup_formula_has_bottle { true }
+      described_class.setup_pour_formula_bottle(&:some_random_method)
+    end
+
+    it "does not raise an error" do
+      expect { subject.pour }.not_to raise_error
+    end
+  end
+end
diff --git a/Library/Homebrew/test/bottle_hooks_test.rb b/Library/Homebrew/test/bottle_hooks_test.rb
deleted file mode 100644
index 3535d80ef..000000000
--- a/Library/Homebrew/test/bottle_hooks_test.rb
+++ /dev/null
@@ -1,47 +0,0 @@
-require "testing_env"
-require "formula_installer"
-require "hooks/bottles"
-
-class BottleHookTests < Homebrew::TestCase
-  class FormulaDouble
-    def bottle; end
-    def local_bottle_path; end
-
-    def bottle_disabled?
-      false
-    end
-
-    def some_random_method
-      true
-    end
-  end
-
-  def setup
-    @fi = FormulaInstaller.new FormulaDouble.new
-  end
-
-  def test_has_bottle
-    Homebrew::Hooks::Bottles.setup_formula_has_bottle(&:some_random_method)
-    assert_predicate @fi, :pour_bottle?
-  end
-
-  def test_has_no_bottle
-    Homebrew::Hooks::Bottles.setup_formula_has_bottle do |f|
-      !f.some_random_method
-    end
-    refute_predicate @fi, :pour_bottle?
-  end
-
-  def test_pour_formula_bottle
-    Homebrew::Hooks::Bottles.setup_formula_has_bottle do |_f|
-      true
-    end
-
-    Homebrew::Hooks::Bottles.setup_pour_formula_bottle(&:some_random_method)
-    @fi.pour
-  end
-
-  def teardown
-    Homebrew::Hooks::Bottles.reset_hooks
-  end
-end
diff --git a/Library/Homebrew/test/bottle_test.rb b/Library/Homebrew/test/bottle_test.rb
deleted file mode 100644
index c10746e09..000000000
--- a/Library/Homebrew/test/bottle_test.rb
+++ /dev/null
@@ -1,21 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestBottle < IntegrationCommandTestCase
-  def test_bottle
-    cmd("install", "--build-bottle", testball)
-    assert_match "Formula not from core or any taps",
-                 cmd_fail("bottle", "--no-rebuild", testball)
-
-    setup_test_formula "testball"
-
-    # `brew bottle` should not fail with dead symlink
-    # https://github.com/Homebrew/legacy-homebrew/issues/49007
-    (HOMEBREW_CELLAR/"testball/0.1").cd do
-      FileUtils.ln_s "not-exist", "symlink"
-    end
-    assert_match(/testball-0\.1.*\.bottle\.tar\.gz/,
-                  cmd_output("bottle", "--no-rebuild", "testball"))
-  ensure
-    FileUtils.rm_f Dir["testball-0.1*.bottle.tar.gz"]
-  end
-end
diff --git a/Library/Homebrew/test/build_environment_spec.rb b/Library/Homebrew/test/build_environment_spec.rb
new file mode 100644
index 000000000..5a3cec452
--- /dev/null
+++ b/Library/Homebrew/test/build_environment_spec.rb
@@ -0,0 +1,66 @@
+require "build_environment"
+
+RSpec::Matchers.alias_matcher :use_userpaths, :be_userpaths
+
+describe BuildEnvironment do
+  let(:env) { described_class.new }
+
+  describe "#<<" do
+    it "returns itself" do
+      expect(env << :foo).to be env
+    end
+  end
+
+  describe "#merge" do
+    it "returns itself" do
+      expect(env.merge([])).to be env
+    end
+  end
+
+  describe "#std?" do
+    it "returns true if the environment contains :std" do
+      env << :std
+      expect(env).to be_std
+    end
+
+    it "returns false if the environment does not contain :std" do
+      expect(env).not_to be_std
+    end
+  end
+
+  describe "#userpaths?" do
+    it "returns true if the environment contains :userpaths" do
+      env << :userpaths
+      expect(env).to use_userpaths
+    end
+
+    it "returns false if the environment does not contain :userpaths" do
+      expect(env).not_to use_userpaths
+    end
+  end
+end
+
+describe BuildEnvironmentDSL do
+  subject { double.extend(described_class) }
+
+  context "single argument" do
+    before(:each) do
+      subject.instance_eval do
+        env :userpaths
+      end
+    end
+
+    its(:env) { is_expected.to use_userpaths }
+  end
+
+  context "multiple arguments" do
+    before(:each) do
+      subject.instance_eval do
+        env :userpaths, :std
+      end
+    end
+
+    its(:env) { is_expected.to be_std }
+    its(:env) { is_expected.to use_userpaths }
+  end
+end
diff --git a/Library/Homebrew/test/build_environment_test.rb b/Library/Homebrew/test/build_environment_test.rb
deleted file mode 100644
index 73a1c95f7..000000000
--- a/Library/Homebrew/test/build_environment_test.rb
+++ /dev/null
@@ -1,45 +0,0 @@
-require "testing_env"
-require "build_environment"
-
-class BuildEnvironmentTests < Homebrew::TestCase
-  def setup
-    @env = BuildEnvironment.new
-  end
-
-  def test_shovel_returns_self
-    assert_same @env, @env << :foo
-  end
-
-  def test_merge_returns_self
-    assert_same @env, @env.merge([])
-  end
-
-  def test_std?
-    @env << :std
-    assert_predicate @env, :std?
-  end
-
-  def test_userpaths?
-    @env << :userpaths
-    assert_predicate @env, :userpaths?
-  end
-end
-
-class BuildEnvironmentDSLTests < Homebrew::TestCase
-  def make_instance(&block)
-    obj = Object.new.extend(BuildEnvironmentDSL)
-    obj.instance_eval(&block)
-    obj
-  end
-
-  def test_env_single_argument
-    obj = make_instance { env :userpaths }
-    assert_predicate obj.env, :userpaths?
-  end
-
-  def test_env_multiple_arguments
-    obj = make_instance { env :userpaths, :std }
-    assert_predicate obj.env, :userpaths?
-    assert_predicate obj.env, :std?
-  end
-end
diff --git a/Library/Homebrew/test/build_options_spec.rb b/Library/Homebrew/test/build_options_spec.rb
new file mode 100644
index 000000000..5acc12f30
--- /dev/null
+++ b/Library/Homebrew/test/build_options_spec.rb
@@ -0,0 +1,52 @@
+require "build_options"
+require "options"
+
+RSpec::Matchers.alias_matcher :be_built_with, :be_with
+RSpec::Matchers.alias_matcher :be_built_without, :be_without
+
+describe BuildOptions do
+  subject { described_class.new(args, opts) }
+  let(:bad_build) { described_class.new(bad_args, opts) }
+  let(:args) { Options.create(%w[--with-foo --with-bar --without-qux]) }
+  let(:opts) { Options.create(%w[--with-foo --with-bar --without-baz --without-qux]) }
+  let(:bad_args) { Options.create(%w[--with-foo --with-bar --without-bas --without-qux --without-abc]) }
+
+  specify "#include?" do
+    expect(subject).to include("with-foo")
+    expect(subject).not_to include("with-qux")
+    expect(subject).not_to include("--with-foo")
+  end
+
+  specify "#with?" do
+    expect(subject).to be_built_with("foo")
+    expect(subject).to be_built_with("bar")
+    expect(subject).to be_built_with("baz")
+  end
+
+  specify "#without?" do
+    expect(subject).to be_built_without("qux")
+    expect(subject).to be_built_without("xyz")
+  end
+
+  specify "#used_options" do
+    expect(subject.used_options).to include("--with-foo")
+    expect(subject.used_options).to include("--with-bar")
+  end
+
+  specify "#unused_options" do
+    expect(subject.unused_options).to include("--without-baz")
+  end
+
+  specify "#invalid_options" do
+    expect(subject.invalid_options).to be_empty
+    expect(bad_build.invalid_options).to include("--without-bas")
+    expect(bad_build.invalid_options).to include("--without-abc")
+    expect(bad_build.invalid_options).not_to include("--with-foo")
+    expect(bad_build.invalid_options).not_to include("--with-baz")
+  end
+
+  specify "#invalid_option_names" do
+    expect(subject.invalid_option_names).to be_empty
+    expect(bad_build.invalid_option_names).to eq(%w[--without-abc --without-bas])
+  end
+end
diff --git a/Library/Homebrew/test/build_options_test.rb b/Library/Homebrew/test/build_options_test.rb
deleted file mode 100644
index e460d25cc..000000000
--- a/Library/Homebrew/test/build_options_test.rb
+++ /dev/null
@@ -1,49 +0,0 @@
-require "testing_env"
-require "build_options"
-require "options"
-
-class BuildOptionsTests < Homebrew::TestCase
-  def setup
-    args = Options.create(%w[--with-foo --with-bar --without-qux])
-    opts = Options.create(%w[--with-foo --with-bar --without-baz --without-qux])
-    @build = BuildOptions.new(args, opts)
-    bad_args = Options.create(%w[--with-foo --with-bar --without-bas --without-qux --without-abc])
-    @bad_build = BuildOptions.new(bad_args, opts)
-  end
-
-  def test_include
-    assert_includes @build, "with-foo"
-    refute_includes @build, "with-qux"
-    refute_includes @build, "--with-foo"
-  end
-
-  def test_with_without
-    assert @build.with?("foo")
-    assert @build.with?("bar")
-    assert @build.with?("baz")
-    assert @build.without?("qux")
-    assert @build.without?("xyz")
-  end
-
-  def test_used_options
-    assert_includes @build.used_options, "--with-foo"
-    assert_includes @build.used_options, "--with-bar"
-  end
-
-  def test_unused_options
-    assert_includes @build.unused_options, "--without-baz"
-  end
-
-  def test_invalid_options
-    assert_empty @build.invalid_options
-    assert_includes @bad_build.invalid_options, "--without-bas"
-    assert_includes @bad_build.invalid_options, "--without-abc"
-    refute_includes @bad_build.invalid_options, "--with-foo"
-    refute_includes @bad_build.invalid_options, "--with-baz"
-  end
-
-  def test_invalid_option_names
-    assert_empty @build.invalid_option_names
-    assert_equal @bad_build.invalid_option_names, %w[--without-abc --without-bas]
-  end
-end
diff --git a/Library/Homebrew/test/bundle_test.rb b/Library/Homebrew/test/bundle_test.rb
deleted file mode 100644
index ae47977d8..000000000
--- a/Library/Homebrew/test/bundle_test.rb
+++ /dev/null
@@ -1,22 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestBundle < IntegrationCommandTestCase
-  def test_bundle
-    needs_test_cmd_taps
-    setup_remote_tap("homebrew/bundle")
-    HOMEBREW_REPOSITORY.cd do
-      shutup do
-        system "git", "init"
-        system "git", "commit", "--allow-empty", "-m", "This is a test commit"
-      end
-    end
-
-    mktmpdir do |path|
-      FileUtils.touch "#{path}/Brewfile"
-      Dir.chdir path do
-        assert_equal "The Brewfile's dependencies are satisfied.",
-          cmd("bundle", "check")
-      end
-    end
-  end
-end
diff --git a/Library/Homebrew/test/cache_formula_test.rb b/Library/Homebrew/test/cache_formula_test.rb
deleted file mode 100644
index 6dcb6a745..000000000
--- a/Library/Homebrew/test/cache_formula_test.rb
+++ /dev/null
@@ -1,8 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestCacheFormula < IntegrationCommandTestCase
-  def test_cache_formula
-    assert_match %r{#{HOMEBREW_CACHE}/testball-},
-                 cmd("--cache", testball)
-  end
-end
diff --git a/Library/Homebrew/test/cache_test.rb b/Library/Homebrew/test/cache_test.rb
deleted file mode 100644
index 3a9e6b011..000000000
--- a/Library/Homebrew/test/cache_test.rb
+++ /dev/null
@@ -1,8 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestCache < IntegrationCommandTestCase
-  def test_cache
-    assert_equal HOMEBREW_CACHE.to_s,
-                 cmd("--cache")
-  end
-end
diff --git a/Library/Homebrew/test/cask_test.rb b/Library/Homebrew/test/cask_test.rb
deleted file mode 100644
index d5b81facb..000000000
--- a/Library/Homebrew/test/cask_test.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestCask < IntegrationCommandTestCase
-  def test_cask
-    needs_test_cmd_taps
-    needs_macos
-    setup_remote_tap("caskroom/cask")
-    cmd("cask", "list", "--caskroom=#{HOMEBREW_PREFIX}/Caskroom")
-  end
-end
diff --git a/Library/Homebrew/test/cat_test.rb b/Library/Homebrew/test/cat_test.rb
deleted file mode 100644
index bb37b5fde..000000000
--- a/Library/Homebrew/test/cat_test.rb
+++ /dev/null
@@ -1,8 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestCat < IntegrationCommandTestCase
-  def test_cat
-    formula_file = setup_test_formula "testball"
-    assert_equal formula_file.read.chomp, cmd("cat", "testball")
-  end
-end
diff --git a/Library/Homebrew/test/caveats_spec.rb b/Library/Homebrew/test/caveats_spec.rb
new file mode 100644
index 000000000..d8be9dc52
--- /dev/null
+++ b/Library/Homebrew/test/caveats_spec.rb
@@ -0,0 +1,29 @@
+require "formula"
+require "caveats"
+
+describe Caveats do
+  subject { described_class.new(f) }
+  let(:f) { formula { url "foo-1.0" } }
+
+  specify "#f" do
+    expect(subject.f).to eq(f)
+  end
+
+  describe "#empty?" do
+    it "returns true if the Formula has no caveats" do
+      expect(subject).to be_empty
+    end
+
+    it "returns false if the Formula has caveats" do
+      f = formula do
+        url "foo-1.0"
+
+        def caveats
+          "something"
+        end
+      end
+
+      expect(described_class.new(f)).not_to be_empty
+    end
+  end
+end
diff --git a/Library/Homebrew/test/caveats_test.rb b/Library/Homebrew/test/caveats_test.rb
deleted file mode 100644
index 9eaac5792..000000000
--- a/Library/Homebrew/test/caveats_test.rb
+++ /dev/null
@@ -1,29 +0,0 @@
-require "testing_env"
-require "formula"
-require "caveats"
-
-class CaveatsTests < Homebrew::TestCase
-  def setup
-    @f = formula { url "foo-1.0" }
-    @c = Caveats.new @f
-  end
-
-  def test_f
-    assert_equal @f, @c.f
-  end
-
-  def test_empty?
-    assert @c.empty?
-
-    f = formula do
-      url "foo-1.0"
-
-      def caveats
-        "something"
-      end
-    end
-    c = Caveats.new f
-
-    refute c.empty?
-  end
-end
diff --git a/Library/Homebrew/test/cellar_formula_test.rb b/Library/Homebrew/test/cellar_formula_test.rb
deleted file mode 100644
index 38a934a7b..000000000
--- a/Library/Homebrew/test/cellar_formula_test.rb
+++ /dev/null
@@ -1,8 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestCellarFormula < IntegrationCommandTestCase
-  def test_cellar_formula
-    assert_match "#{HOMEBREW_CELLAR}/testball",
-                 cmd("--cellar", testball)
-  end
-end
diff --git a/Library/Homebrew/test/cellar_test.rb b/Library/Homebrew/test/cellar_test.rb
deleted file mode 100644
index 74d5389f8..000000000
--- a/Library/Homebrew/test/cellar_test.rb
+++ /dev/null
@@ -1,8 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestCellar < IntegrationCommandTestCase
-  def test_cellar
-    assert_equal HOMEBREW_CELLAR.to_s,
-                 cmd("--cellar")
-  end
-end
diff --git a/Library/Homebrew/test/checksum_spec.rb b/Library/Homebrew/test/checksum_spec.rb
new file mode 100644
index 000000000..acab348b7
--- /dev/null
+++ b/Library/Homebrew/test/checksum_spec.rb
@@ -0,0 +1,19 @@
+require "checksum"
+
+describe Checksum do
+  describe "#empty?" do
+    subject { described_class.new(:sha256, "") }
+    it { is_expected.to be_empty }
+  end
+
+  describe "#==" do
+    subject { described_class.new(:sha256, TEST_SHA256) }
+    let(:other) { described_class.new(:sha256, TEST_SHA256) }
+    let(:other_reversed) { described_class.new(:sha256, TEST_SHA256.reverse) }
+    let(:other_sha1) { described_class.new(:sha1, TEST_SHA1) }
+
+    it { is_expected.to eq(other) }
+    it { is_expected.not_to eq(other_reversed) }
+    it { is_expected.not_to eq(other_sha1) }
+  end
+end
diff --git a/Library/Homebrew/test/checksum_test.rb b/Library/Homebrew/test/checksum_test.rb
deleted file mode 100644
index 5505f6824..000000000
--- a/Library/Homebrew/test/checksum_test.rb
+++ /dev/null
@@ -1,22 +0,0 @@
-require "testing_env"
-require "checksum"
-
-class ChecksumTests < Homebrew::TestCase
-  def test_empty?
-    assert_empty Checksum.new(:sha256, "")
-  end
-
-  def test_equality
-    a = Checksum.new(:sha256, TEST_SHA256)
-    b = Checksum.new(:sha256, TEST_SHA256)
-    assert_equal a, b
-
-    a = Checksum.new(:sha256, TEST_SHA256)
-    b = Checksum.new(:sha256, TEST_SHA256.reverse)
-    refute_equal a, b
-
-    a = Checksum.new(:sha1, TEST_SHA1)
-    b = Checksum.new(:sha256, TEST_SHA256)
-    refute_equal a, b
-  end
-end
diff --git a/Library/Homebrew/test/checksum_verification_test.rb b/Library/Homebrew/test/checksum_verification_test.rb
index 9017b528d..4c674edd2 100644
--- a/Library/Homebrew/test/checksum_verification_test.rb
+++ b/Library/Homebrew/test/checksum_verification_test.rb
@@ -17,10 +17,6 @@ class ChecksumVerificationTests < Homebrew::TestCase
     end
   end
 
-  def teardown
-    @_f.clear_cache
-  end
-
   def test_good_sha256
     formula do
       sha256 TESTBALL_SHA256
diff --git a/Library/Homebrew/test/cleaner_test.rb b/Library/Homebrew/test/cleaner_test.rb
index ac108421c..05a91b90b 100644
--- a/Library/Homebrew/test/cleaner_test.rb
+++ b/Library/Homebrew/test/cleaner_test.rb
@@ -6,14 +6,11 @@ class CleanerTests < Homebrew::TestCase
   include FileUtils
 
   def setup
+    super
     @f = formula("cleaner_test") { url "foo-1.0" }
     @f.prefix.mkpath
   end
 
-  def teardown
-    @f.rack.rmtree if @f.rack.exist?
-  end
-
   def test_clean_file
     @f.bin.mkpath
     @f.lib.mkpath
diff --git a/Library/Homebrew/test/cleanup_test.rb b/Library/Homebrew/test/cleanup_test.rb
index bb8e1cdc6..bc7a6713c 100644
--- a/Library/Homebrew/test/cleanup_test.rb
+++ b/Library/Homebrew/test/cleanup_test.rb
@@ -5,23 +5,16 @@ require "fileutils"
 require "pathname"
 require "testing_env"
 
-class IntegrationCommandTestCleanup < IntegrationCommandTestCase
-  def test_cleanup
-    (HOMEBREW_CACHE/"test").write "test"
-    assert_match "#{HOMEBREW_CACHE}/test", cmd("cleanup", "--prune=all")
-  end
-end
-
 class CleanupTests < Homebrew::TestCase
   def setup
+    super
     @ds_store = Pathname.new "#{HOMEBREW_PREFIX}/Library/.DS_Store"
     FileUtils.touch @ds_store
   end
 
   def teardown
     FileUtils.rm_f @ds_store
-    ARGV.delete "--dry-run"
-    ARGV.delete "--prune=all"
+    super
   end
 
   def test_cleanup
@@ -36,28 +29,40 @@ class CleanupTests < Homebrew::TestCase
   end
 
   def test_cleanup_formula
-    f1 = Class.new(Testball) { version "0.1" }.new
-    f2 = Class.new(Testball) { version "0.2" }.new
-    f3 = Class.new(Testball) { version "0.3" }.new
+    f1 = Class.new(Testball) do
+      version "1.0"
+    end.new
+    f2 = Class.new(Testball) do
+      version "0.2"
+      version_scheme 1
+    end.new
+    f3 = Class.new(Testball) do
+      version "0.3"
+      version_scheme 1
+    end.new
+    f4 = Class.new(Testball) do
+      version "0.1"
+      version_scheme 2
+    end.new
 
     shutup do
-      f1.brew { f1.install }
-      f2.brew { f2.install }
-      f3.brew { f3.install }
+      [f1, f2, f3, f4].each do |f|
+        f.brew { f.install }
+        Tab.create(f, DevelopmentTools.default_compiler, :libcxx).write
+      end
     end
 
     assert_predicate f1, :installed?
     assert_predicate f2, :installed?
     assert_predicate f3, :installed?
+    assert_predicate f4, :installed?
 
     shutup { Homebrew::Cleanup.cleanup_formula f3 }
 
     refute_predicate f1, :installed?
     refute_predicate f2, :installed?
     assert_predicate f3, :installed?
-  ensure
-    [f1, f2, f3].each(&:clear_cache)
-    f3.rack.rmtree
+    assert_predicate f4, :installed?
   end
 
   def test_cleanup_logs
diff --git a/Library/Homebrew/test/cmd/--cache_spec.rb b/Library/Homebrew/test/cmd/--cache_spec.rb
new file mode 100644
index 000000000..fb3c9cee6
--- /dev/null
+++ b/Library/Homebrew/test/cmd/--cache_spec.rb
@@ -0,0 +1,15 @@
+describe "brew --cache", :integration_test do
+  it "print the location of Homebrew's cache when no argument is given" do
+    expect { brew "--cache" }
+      .to output("#{HOMEBREW_CACHE}\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "prints all cache files for a given Formula" do
+    expect { brew "--cache", testball }
+      .to output(%r{#{HOMEBREW_CACHE}/testball-}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/--cellar_spec.rb b/Library/Homebrew/test/cmd/--cellar_spec.rb
new file mode 100644
index 000000000..6c8d7dea6
--- /dev/null
+++ b/Library/Homebrew/test/cmd/--cellar_spec.rb
@@ -0,0 +1,15 @@
+describe "brew --cellar", :integration_test do
+  it "print the location of Homebrew's Cellar when no argument is given" do
+    expect { brew "--cellar" }
+      .to output("#{HOMEBREW_CELLAR}\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "returns the Cellar subdirectory for a given Formula" do
+    expect { brew "--cellar", testball }
+      .to output(%r{#{HOMEBREW_CELLAR}/testball}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/--env_spec.rb b/Library/Homebrew/test/cmd/--env_spec.rb
new file mode 100644
index 000000000..7dd84132a
--- /dev/null
+++ b/Library/Homebrew/test/cmd/--env_spec.rb
@@ -0,0 +1,44 @@
+describe "brew --env", :integration_test do
+  it "prints the Homebrew build environment variables" do
+    expect { brew "--env" }
+      .to output(/CMAKE_PREFIX_PATH="#{Regexp.escape(HOMEBREW_PREFIX)}[:"]/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  describe "--shell=bash" do
+    it "prints the Homebrew build environment variables in Bash syntax" do
+      expect { brew "--env", "--shell=bash" }
+        .to output(/export CMAKE_PREFIX_PATH="#{Regexp.quote(HOMEBREW_PREFIX.to_s)}"/).to_stdout
+        .and not_to_output.to_stderr
+        .and be_a_success
+    end
+  end
+
+  describe "--shell=fish" do
+    it "prints the Homebrew build environment variables in Fish syntax" do
+      expect { brew "--env", "--shell=fish" }
+        .to output(/set [-]gx CMAKE_PREFIX_PATH "#{Regexp.quote(HOMEBREW_PREFIX.to_s)}"/).to_stdout
+        .and not_to_output.to_stderr
+        .and be_a_success
+    end
+  end
+
+  describe "--shell=tcsh" do
+    it "prints the Homebrew build environment variables in Tcsh syntax" do
+      expect { brew "--env", "--shell=tcsh" }
+        .to output(/setenv CMAKE_PREFIX_PATH #{Regexp.quote(HOMEBREW_PREFIX.to_s)};/).to_stdout
+        .and not_to_output.to_stderr
+        .and be_a_success
+    end
+  end
+
+  describe "--plain" do
+    it "prints the Homebrew build environment variables without quotes" do
+      expect { brew "--env", "--plain" }
+        .to output(/CMAKE_PREFIX_PATH: #{Regexp.quote(HOMEBREW_PREFIX)}/).to_stdout
+        .and not_to_output.to_stderr
+        .and be_a_success
+    end
+  end
+end
diff --git a/Library/Homebrew/test/cmd/--prefix_spec.rb b/Library/Homebrew/test/cmd/--prefix_spec.rb
new file mode 100644
index 000000000..80ef73a97
--- /dev/null
+++ b/Library/Homebrew/test/cmd/--prefix_spec.rb
@@ -0,0 +1,15 @@
+describe "brew --prefix", :integration_test do
+  it "prints the Homebrew prefix when no argument is given" do
+    expect { brew "--prefix" }
+      .to output("#{HOMEBREW_PREFIX}\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "prints a given Formula's prefix" do
+    expect { brew "--prefix", testball }
+      .to output(%r{#{HOMEBREW_CELLAR}/testball}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/--repository_spec.rb b/Library/Homebrew/test/cmd/--repository_spec.rb
new file mode 100644
index 000000000..d3e531f7b
--- /dev/null
+++ b/Library/Homebrew/test/cmd/--repository_spec.rb
@@ -0,0 +1,15 @@
+describe "brew --repository", :integration_test do
+  it "prints the path of the Homebrew repository" do
+    expect { brew "--repository" }
+      .to output("#{HOMEBREW_REPOSITORY}\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "prints the path of a given Tap" do
+    expect { brew "--repository", "foo/bar" }
+      .to output("#{HOMEBREW_LIBRARY}/Taps/foo/homebrew-bar\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/--version_spec.rb b/Library/Homebrew/test/cmd/--version_spec.rb
new file mode 100644
index 000000000..8992629d7
--- /dev/null
+++ b/Library/Homebrew/test/cmd/--version_spec.rb
@@ -0,0 +1,8 @@
+describe "brew --version", :integration_test do
+  it "prints the Homebrew version" do
+    expect { brew "--version" }
+      .to output(/^Homebrew #{Regexp.escape(HOMEBREW_VERSION.to_s)}\n/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/analytics_spec.rb b/Library/Homebrew/test/cmd/analytics_spec.rb
new file mode 100644
index 000000000..aed3a7a33
--- /dev/null
+++ b/Library/Homebrew/test/cmd/analytics_spec.rb
@@ -0,0 +1,52 @@
+describe "brew analytics", :integration_test do
+  before(:each) do
+    HOMEBREW_REPOSITORY.cd do
+      shutup do
+        system "git", "init"
+      end
+    end
+  end
+
+  it "is disabled when HOMEBREW_NO_ANALYTICS is set" do
+    expect { brew "analytics", "HOMEBREW_NO_ANALYTICS" => "1" }
+      .to output(/Analytics is disabled \(by HOMEBREW_NO_ANALYTICS\)/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  context "when HOMEBREW_NO_ANALYTICS is unset" do
+    it "is disabled after running `brew analytics off`" do
+      brew "analytics", "off"
+      expect { brew "analytics", "HOMEBREW_NO_ANALYTICS" => nil }
+        .to output(/Analytics is disabled/).to_stdout
+        .and not_to_output.to_stderr
+        .and be_a_success
+    end
+
+    it "is enabled after running `brew analytics on`" do
+      brew "analytics", "on"
+      expect { brew "analytics", "HOMEBREW_NO_ANALYTICS" => nil }
+        .to output(/Analytics is enabled/).to_stdout
+        .and not_to_output.to_stderr
+        .and be_a_success
+    end
+  end
+
+  it "fails when running `brew analytics on off`" do
+    expect { brew "analytics", "on", "off" }
+      .to output(/Invalid usage/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+  end
+
+  it "fails when running `brew analytics testball`" do
+    expect { brew "analytics", "testball" }
+      .to output(/Invalid usage/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+  end
+
+  it "can generate a new UUID" do
+    expect { brew "analytics", "regenerate-uuid" }.to be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/bundle_spec.rb b/Library/Homebrew/test/cmd/bundle_spec.rb
new file mode 100644
index 000000000..755f9ab3d
--- /dev/null
+++ b/Library/Homebrew/test/cmd/bundle_spec.rb
@@ -0,0 +1,24 @@
+describe "brew bundle", :integration_test, :needs_test_cmd_taps do
+  describe "check" do
+    it "checks if a Brewfile's dependencies are satisfied" do
+      setup_remote_tap "homebrew/bundle"
+
+      HOMEBREW_REPOSITORY.cd do
+        shutup do
+          system "git", "init"
+          system "git", "commit", "--allow-empty", "-m", "This is a test commit"
+        end
+      end
+
+      Dir.mktmpdir do |path|
+        FileUtils.touch "#{path}/Brewfile"
+        Dir.chdir path do
+          expect { brew "bundle", "check" }
+            .to output("The Brewfile's dependencies are satisfied.\n").to_stdout
+            .and not_to_output.to_stderr
+            .and be_a_success
+        end
+      end
+    end
+  end
+end
diff --git a/Library/Homebrew/test/cmd/cask_spec.rb b/Library/Homebrew/test/cmd/cask_spec.rb
new file mode 100644
index 000000000..e46843cab
--- /dev/null
+++ b/Library/Homebrew/test/cmd/cask_spec.rb
@@ -0,0 +1,8 @@
+describe "brew cask", :integration_test, :needs_macos, :needs_official_cmd_taps do
+  describe "list" do
+    it "returns a list of installed Casks" do
+      setup_remote_tap("caskroom/cask")
+      expect { brew "cask", "list" }.to be_a_success
+    end
+  end
+end
diff --git a/Library/Homebrew/test/cmd/cat_spec.rb b/Library/Homebrew/test/cmd/cat_spec.rb
new file mode 100644
index 000000000..8c230abee
--- /dev/null
+++ b/Library/Homebrew/test/cmd/cat_spec.rb
@@ -0,0 +1,11 @@
+describe "brew cat", :integration_test do
+  it "prints the content of a given Formula" do
+    formula_file = setup_test_formula "testball"
+    content = formula_file.read
+
+    expect { brew "cat", "testball" }
+      .to output(content).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/cleanup_spec.rb b/Library/Homebrew/test/cmd/cleanup_spec.rb
new file mode 100644
index 000000000..9e2cf493f
--- /dev/null
+++ b/Library/Homebrew/test/cmd/cleanup_spec.rb
@@ -0,0 +1,12 @@
+describe "brew cleanup", :integration_test do
+  describe "--prune=all" do
+    it "removes all files in Homebrew's cache" do
+      (HOMEBREW_CACHE/"test").write "test"
+
+      expect { brew "cleanup", "--prune=all" }
+        .to output(%r{#{Regexp.escape(HOMEBREW_CACHE)}/test}).to_stdout
+        .and not_to_output.to_stderr
+        .and be_a_success
+    end
+  end
+end
diff --git a/Library/Homebrew/test/cmd/command_spec.rb b/Library/Homebrew/test/cmd/command_spec.rb
new file mode 100644
index 000000000..5d6a67b70
--- /dev/null
+++ b/Library/Homebrew/test/cmd/command_spec.rb
@@ -0,0 +1,13 @@
+describe "brew command", :integration_test do
+  it "returns the file for a given command" do
+    expect { brew "command", "info" }
+      .to output(%r{#{Regexp.escape(HOMEBREW_LIBRARY_PATH)}/cmd/info.rb}).to_stdout
+      .and be_a_success
+  end
+
+  it "fails when the given command is unknown" do
+    expect { brew "command", "does-not-exist" }
+      .to output(/Unknown command/).to_stderr
+      .and be_a_failure
+  end
+end
diff --git a/Library/Homebrew/test/cmd/commands_spec.rb b/Library/Homebrew/test/cmd/commands_spec.rb
new file mode 100644
index 000000000..f42072956
--- /dev/null
+++ b/Library/Homebrew/test/cmd/commands_spec.rb
@@ -0,0 +1,7 @@
+describe "brew commands", :integration_test do
+  it "prints a list of all available commands" do
+    expect { brew "commands" }
+      .to output(/Built-in commands/).to_stdout
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/config_spec.rb b/Library/Homebrew/test/cmd/config_spec.rb
new file mode 100644
index 000000000..7687fcdc7
--- /dev/null
+++ b/Library/Homebrew/test/cmd/config_spec.rb
@@ -0,0 +1,8 @@
+describe "brew config", :integration_test do
+  it "prints information about the current Homebrew configuration" do
+    expect { brew "config" }
+      .to output(/HOMEBREW_VERSION: #{HOMEBREW_VERSION}/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/custom-external-command_spec.rb b/Library/Homebrew/test/cmd/custom-external-command_spec.rb
new file mode 100644
index 000000000..8ccc21fa7
--- /dev/null
+++ b/Library/Homebrew/test/cmd/custom-external-command_spec.rb
@@ -0,0 +1,21 @@
+describe "brew custom-external-command", :integration_test do
+  it "is supported" do
+    Dir.mktmpdir do |path|
+      path = Pathname.new(path)
+
+      cmd = "custom-external-command-#{rand}"
+      file = path/"brew-#{cmd}"
+
+      file.write <<-EOS.undent
+        #!/bin/sh
+        echo 'I am #{cmd}.'
+      EOS
+      FileUtils.chmod "+x", file
+
+      expect { brew cmd, "PATH" => "#{path}#{File::PATH_SEPARATOR}#{ENV["PATH"]}" }
+        .to output("I am #{cmd}.\n").to_stdout
+        .and not_to_output.to_stderr
+        .and be_a_success
+    end
+  end
+end
diff --git a/Library/Homebrew/test/cmd/desc_spec.rb b/Library/Homebrew/test/cmd/desc_spec.rb
new file mode 100644
index 000000000..b09819d81
--- /dev/null
+++ b/Library/Homebrew/test/cmd/desc_spec.rb
@@ -0,0 +1,40 @@
+describe "brew desc", :integration_test do
+  let(:desc_cache) { HOMEBREW_CACHE/"desc_cache.json" }
+
+  it "shows a given Formula's description" do
+    setup_test_formula "testball"
+
+    expect { brew "desc", "testball" }
+      .to output("testball: Some test\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "fails when both --search and --name are specified" do
+    expect { brew "desc", "--search", "--name" }
+      .to output(/Pick one, and only one/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+  end
+
+  describe "--search" do
+    it "fails when no search term is given" do
+      expect { brew "desc", "--search" }
+        .to output(/You must provide a search term/).to_stderr
+        .and not_to_output.to_stdout
+        .and be_a_failure
+    end
+  end
+
+  describe "--description" do
+    it "creates a description cache" do
+      expect(desc_cache).not_to exist
+
+      shutup do
+        expect { brew "desc", "--description", "testball" }.to be_a_success
+      end
+
+      expect(desc_cache).to exist
+    end
+  end
+end
diff --git a/Library/Homebrew/test/cmd/doctor_spec.rb b/Library/Homebrew/test/cmd/doctor_spec.rb
new file mode 100644
index 000000000..530adcd98
--- /dev/null
+++ b/Library/Homebrew/test/cmd/doctor_spec.rb
@@ -0,0 +1,6 @@
+describe "brew doctor", :integration_test do
+  specify "check_integration_test" do
+    expect { brew "doctor", "check_integration_test" }
+      .to output(/This is an integration test/).to_stderr
+  end
+end
diff --git a/Library/Homebrew/test/cmd/fetch_spec.rb b/Library/Homebrew/test/cmd/fetch_spec.rb
new file mode 100644
index 000000000..111d9f85c
--- /dev/null
+++ b/Library/Homebrew/test/cmd/fetch_spec.rb
@@ -0,0 +1,13 @@
+describe "brew fetch", :integration_test do
+  it "downloads the Formula's URL" do
+    setup_test_formula "testball"
+
+    expect(HOMEBREW_CACHE/"testball-0.1.tbz").not_to exist
+
+    shutup do
+      expect { brew "fetch", "testball" }.to be_a_success
+    end
+
+    expect(HOMEBREW_CACHE/"testball-0.1.tbz").to exist
+  end
+end
diff --git a/Library/Homebrew/test/cmd/help_spec.rb b/Library/Homebrew/test/cmd/help_spec.rb
new file mode 100644
index 000000000..6d94d7444
--- /dev/null
+++ b/Library/Homebrew/test/cmd/help_spec.rb
@@ -0,0 +1,47 @@
+describe "brew", :integration_test do
+  it "prints help when no argument is given" do
+    expect { brew }
+      .to output(/Example usage:\n/).to_stderr
+      .and be_a_failure
+  end
+
+  describe "help" do
+    it "prints help" do
+      expect { brew "help" }
+        .to output(/Example usage:\n/).to_stdout
+        .and be_a_success
+    end
+
+    it "prints help for a documented Ruby command" do
+      expect { brew "help", "cat" }
+        .to output(/^brew cat/).to_stdout
+        .and be_a_success
+    end
+
+    it "prints help for a documented shell command" do
+      expect { brew "help", "update" }
+        .to output(/^brew update/).to_stdout
+        .and be_a_success
+    end
+
+    it "prints help for a documented Ruby developer command" do
+      expect { brew "help", "update-test" }
+        .to output(/^brew update-test/).to_stdout
+        .and be_a_success
+    end
+
+    it "fails when given an unknown command" do
+      expect { brew "help", "command-that-does-not-exist" }
+        .to output(/Unknown command: command-that-does-not-exist/).to_stderr
+        .and be_a_failure
+    end
+  end
+
+  describe "cat" do
+    it "prints help when no argument is given" do
+      expect { brew "cat" }
+        .to output(/^brew cat/).to_stderr
+        .and be_a_failure
+    end
+  end
+end
diff --git a/Library/Homebrew/test/cmd/home_spec.rb b/Library/Homebrew/test/cmd/home_spec.rb
new file mode 100644
index 000000000..5a4070492
--- /dev/null
+++ b/Library/Homebrew/test/cmd/home_spec.rb
@@ -0,0 +1,17 @@
+describe "brew home", :integration_test do
+  it "opens the Homebrew homepage when no argument is given" do
+    expect { brew "home", "HOMEBREW_BROWSER" => "echo" }
+      .to output("#{HOMEBREW_WWW}\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "opens the homepage for a given Formula" do
+    setup_test_formula "testball"
+
+    expect { brew "home", "testball", "HOMEBREW_BROWSER" => "echo" }
+      .to output("#{Formula["testball"].homepage}\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/info_spec.rb b/Library/Homebrew/test/cmd/info_spec.rb
new file mode 100644
index 000000000..8deef3d23
--- /dev/null
+++ b/Library/Homebrew/test/cmd/info_spec.rb
@@ -0,0 +1,30 @@
+require "cmd/info"
+
+describe "brew info", :integration_test do
+  it "prints information about a given Formula" do
+    setup_test_formula "testball"
+
+    expect { brew "info", "testball" }
+      .to output(/testball: stable 0.1/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
+
+describe Homebrew do
+  let(:remote) { "https://github.com/Homebrew/homebrew-core" }
+
+  specify "::github_remote_path" do
+    expect(subject.github_remote_path(remote, "Formula/git.rb"))
+      .to eq("https://github.com/Homebrew/homebrew-core/blob/master/Formula/git.rb")
+
+    expect(subject.github_remote_path("#{remote}.git", "Formula/git.rb"))
+      .to eq("https://github.com/Homebrew/homebrew-core/blob/master/Formula/git.rb")
+
+    expect(subject.github_remote_path("git@github.com:user/repo", "foo.rb"))
+      .to eq("https://github.com/user/repo/blob/master/foo.rb")
+
+    expect(subject.github_remote_path("https://mywebsite.com", "foo/bar.rb"))
+      .to eq("https://mywebsite.com/foo/bar.rb")
+  end
+end
diff --git a/Library/Homebrew/test/cmd/install_spec.rb b/Library/Homebrew/test/cmd/install_spec.rb
new file mode 100644
index 000000000..c1240a30e
--- /dev/null
+++ b/Library/Homebrew/test/cmd/install_spec.rb
@@ -0,0 +1,243 @@
+describe "brew install", :integration_test do
+  it "installs Formulae" do
+    setup_test_formula "testball1"
+
+    expect { brew "install", "testball1", "--head" }
+      .to output(/Specify `\-\-HEAD`/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+
+    expect { brew "install", "testball1", "--HEAD" }
+      .to output(/No head is defined/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+
+    expect { brew "install", "testball1", "--devel" }
+      .to output(/No devel block/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+
+    expect { brew "install", "testball1" }
+      .to output(%r{#{HOMEBREW_CELLAR}/testball1/0\.1}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "install", "testball1" }
+      .to output(/testball1\-0\.1 already installed/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_success
+
+    expect { brew "install", "macruby" }
+      .to output(/MacRuby is not packaged/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+
+    expect { brew "install", "formula" }
+      .to output(/No available formula/).to_stderr
+      .and output(/Searching for similarly named formulae/).to_stdout
+      .and be_a_failure
+
+    expect { brew "install", "testball" }
+      .to output(/This similarly named formula was found/).to_stdout
+      .and output(/No available formula/).to_stderr
+      .and be_a_failure
+
+    setup_test_formula "testball2"
+    expect { brew "install", "testball" }
+      .to output(/These similarly named formulae were found/).to_stdout
+      .and output(/No available formula/).to_stderr
+      .and be_a_failure
+
+    install_and_rename_coretap_formula "testball1", "testball2"
+    expect { brew "install", "testball2" }
+      .to output(/testball1 already installed, it's just not migrated/).to_stderr
+      .and output(/You can migrate formula with `brew migrate testball2`/).to_stdout
+      .and be_a_success
+  end
+
+  specify "install failures" do
+    path = setup_test_formula "testball1", <<-EOS.undent
+      version "1.0"
+    EOS
+
+    expect { brew "install", "testball1" }
+      .to output(%r{#{HOMEBREW_CELLAR}/testball1/1\.0}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    FileUtils.rm path
+    setup_test_formula "testball1", <<-EOS.undent
+      version "2.0"
+
+      devel do
+        url "#{Formulary.factory("testball1").stable.url}"
+        sha256 "#{TESTBALL_SHA256}"
+        version "3.0"
+      end
+    EOS
+
+    expect { brew "install", "testball1" }
+      .to output(/first `brew unlink testball1`/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+
+    expect { brew "unlink", "testball1" }
+      .to output(%r{#{HOMEBREW_CELLAR}/testball1/1\.0}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "install", "testball1", "--devel" }
+      .to output(%r{#{HOMEBREW_CELLAR}/testball1/3\.0}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "unlink", "testball1" }
+      .to output(%r{#{HOMEBREW_CELLAR}/testball1/3\.0}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "install", "testball1" }
+      .to output(%r{#{HOMEBREW_CELLAR}/testball1/2\.0}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    shutup do
+      expect { brew "switch", "testball1", "3.0" }.to be_a_success
+    end
+
+    expect { brew "install", "testball1" }
+      .to output(/already installed, however linked version is/).to_stderr
+      .and output(/`brew switch testball1 2.0`/).to_stdout
+      .and be_a_success
+
+    expect { brew "unlink", "testball1" }
+      .to output(%r{#{HOMEBREW_CELLAR}/testball1/3\.0}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "install", "testball1" }
+      .to output(/just not linked/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_success
+  end
+
+  it "can install keg-only Formulae" do
+    path_keg_only = setup_test_formula "testball1", <<-EOS.undent
+      version "1.0"
+
+      keg_only "test reason"
+    EOS
+
+    expect { brew "install", "testball1" }
+      .to output(%r{#{HOMEBREW_CELLAR}/testball1/1\.0}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    FileUtils.rm path_keg_only
+    setup_test_formula "testball1", <<-EOS.undent
+      version "2.0"
+
+      keg_only "test reason"
+    EOS
+
+    expect { brew "install", "testball1" }
+      .to output(/keg-only and another version is linked to opt/).to_stderr
+      .and output(/Use `brew install --force`/).to_stdout
+      .and be_a_success
+
+    expect { brew "install", "testball1", "--force" }
+      .to output(%r{#{HOMEBREW_CELLAR}/testball1/2\.0}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "can install HEAD Formulae" do
+    repo_path = HOMEBREW_CACHE.join("repo")
+    repo_path.join("bin").mkpath
+
+    repo_path.cd do
+      shutup do
+        system "git", "init"
+        system "git", "remote", "add", "origin", "https://github.com/Homebrew/homebrew-foo"
+        FileUtils.touch "bin/something.bin"
+        FileUtils.touch "README"
+        system "git", "add", "--all"
+        system "git", "commit", "-m", "Initial repo commit"
+      end
+    end
+
+    setup_test_formula "testball1", <<-EOS.undent
+      version "1.0"
+
+      head "file://#{repo_path}", :using => :git
+
+      def install
+        prefix.install Dir["*"]
+      end
+    EOS
+
+    # Ignore dependencies, because we'll try to resolve requirements in build.rb
+    # and there will be the git requirement, but we cannot instantiate git
+    # formula since we only have testball1 formula.
+    expect { brew "install", "testball1", "--HEAD", "--ignore-dependencies" }
+      .to output(%r{#{HOMEBREW_CELLAR}/testball1/HEAD\-d5eb689}).to_stdout
+      .and output(/Cloning into/).to_stderr
+      .and be_a_success
+
+    expect { brew "install", "testball1", "--HEAD", "--ignore-dependencies" }
+      .to output(/testball1\-HEAD\-d5eb689 already installed/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_success
+
+    expect { brew "unlink", "testball1" }
+      .to output(%r{#{HOMEBREW_CELLAR}/testball1/HEAD\-d5eb689}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "install", "testball1" }
+      .to output(%r{#{HOMEBREW_CELLAR}/testball1/1\.0}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "ignores invalid options" do
+    setup_test_formula "testball1"
+    expect { brew "install", "testball1", "--with-fo" }
+      .to output(/testball1: this formula has no \-\-with\-fo option so it will be ignored!/).to_stderr
+      .and output(/Downloading file/).to_stdout
+      .and be_a_success
+  end
+
+  it "succeeds when a non-fatal requirement isn't satisfied" do
+    setup_test_formula "testball1", <<-EOS.undent
+      class NonFatalRequirement < Requirement
+        satisfy { false }
+      end
+
+      depends_on NonFatalRequirement
+    EOS
+
+    # FIXME: This should output to STDERR.
+    expect { brew "install", "testball1" }
+      .to output(/NonFatalRequirement unsatisfied!/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "fails when a fatal requirement isn't satisfied" do
+    setup_test_formula "testball1", <<-EOS.undent
+      class FatalRequirement < Requirement
+        fatal true
+        satisfy { false }
+      end
+
+      depends_on FatalRequirement
+    EOS
+
+    # FIXME: This should output to STDERR.
+    expect { brew "install", "testball1" }
+      .to output(/FatalRequirement unsatisfied!/).to_stdout
+      .and output(/An unsatisfied requirement failed this build./).to_stderr
+      .and be_a_failure
+  end
+end
diff --git a/Library/Homebrew/test/cmd/irb_spec.rb b/Library/Homebrew/test/cmd/irb_spec.rb
new file mode 100644
index 000000000..44410fabe
--- /dev/null
+++ b/Library/Homebrew/test/cmd/irb_spec.rb
@@ -0,0 +1,24 @@
+describe "brew irb", :integration_test do
+  it "starts an interactive Homebrew shell session" do
+    setup_test_formula "testball"
+
+    irb_test = HOMEBREW_TEMP/"irb-test.rb"
+    irb_test.write <<-EOS.undent
+      "testball".f
+      :testball.f
+      exit
+    EOS
+
+    expect { brew "irb", irb_test }
+      .to output(/Interactive Homebrew Shell/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  specify "--examples" do
+    expect { brew "irb", "--examples" }
+      .to output(/'v8'\.f # => instance of the v8 formula/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/leaves_spec.rb b/Library/Homebrew/test/cmd/leaves_spec.rb
new file mode 100644
index 000000000..cd93d7e3d
--- /dev/null
+++ b/Library/Homebrew/test/cmd/leaves_spec.rb
@@ -0,0 +1,23 @@
+describe "brew leaves", :integration_test do
+  it "prints all Formulae that are not dependencies of other Formulae" do
+    setup_test_formula "foo"
+    setup_test_formula "bar"
+
+    expect { brew "leaves" }
+      .to be_a_success
+      .and not_to_output.to_stdout
+      .and not_to_output.to_stderr
+
+    (HOMEBREW_CELLAR/"foo/0.1/somedir").mkpath
+    expect { brew "leaves" }
+      .to output("foo\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    (HOMEBREW_CELLAR/"bar/0.1/somedir").mkpath
+    expect { brew "leaves" }
+      .to output("bar\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/link_spec.rb b/Library/Homebrew/test/cmd/link_spec.rb
new file mode 100644
index 000000000..7b85c96dc
--- /dev/null
+++ b/Library/Homebrew/test/cmd/link_spec.rb
@@ -0,0 +1,56 @@
+describe "brew link", :integration_test do
+  it "fails when no argument is given" do
+    expect { brew "link" }
+      .to output(/This command requires a keg argument/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+  end
+
+  it "does not fail if the given Formula is already linked" do
+    setup_test_formula "testball1"
+
+    shutup do
+      expect { brew "install", "testball1" }.to be_a_success
+      expect { brew "link", "testball1" }.to be_a_success
+    end
+  end
+
+  it "links a given Formula" do
+    setup_test_formula "testball1"
+
+    shutup do
+      expect { brew "install", "testball1" }.to be_a_success
+      expect { brew "unlink", "testball1" }.to be_a_success
+    end
+
+    expect { brew "link", "--dry-run", "testball1" }
+      .to output(/Would link/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "link", "--dry-run", "--overwrite", "testball1" }
+      .to output(/Would remove/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "link", "testball1" }
+      .to output(/Linking/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "refuses to link keg-only Formulae" do
+    setup_test_formula "testball1", <<-EOS.undent
+      keg_only "just because"
+    EOS
+
+    shutup do
+      expect { brew "install", "testball1" }.to be_a_success
+    end
+
+    expect { brew "link", "testball1" }
+      .to output(/testball1 is keg-only/).to_stderr
+      .and output(/Note that doing so can interfere with building software\./).to_stdout
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/linkapps_spec.rb b/Library/Homebrew/test/cmd/linkapps_spec.rb
new file mode 100644
index 000000000..42118a215
--- /dev/null
+++ b/Library/Homebrew/test/cmd/linkapps_spec.rb
@@ -0,0 +1,24 @@
+describe "brew linkapps", :integration_test do
+  let(:home_dir) { @home_dir = Pathname.new(Dir.mktmpdir) }
+  let(:apps_dir) { home_dir/"Applications" }
+
+  after(:each) do
+    home_dir.rmtree unless @home_dir.nil?
+  end
+
+  it "symlinks applications" do
+    apps_dir.mkpath
+
+    setup_test_formula "testball"
+
+    source_app = HOMEBREW_CELLAR/"testball/0.1/TestBall.app"
+    source_app.mkpath
+
+    expect { brew "linkapps", "--local", "HOME" => home_dir }
+      .to output(/Linking: #{Regexp.escape(source_app)}/).to_stdout
+      .and output(/`brew linkapps` has been deprecated/).to_stderr
+      .and be_a_success
+
+    expect(apps_dir/"TestBall.app").to be_a_symlink
+  end
+end
diff --git a/Library/Homebrew/test/cmd/list_spec.rb b/Library/Homebrew/test/cmd/list_spec.rb
new file mode 100644
index 000000000..df7394d7b
--- /dev/null
+++ b/Library/Homebrew/test/cmd/list_spec.rb
@@ -0,0 +1,14 @@
+describe "brew list", :integration_test do
+  let(:formulae) { %w[bar foo qux] }
+
+  it "prints all installed Formulae" do
+    formulae.each do |f|
+      (HOMEBREW_CELLAR/f/"1.0/somedir").mkpath
+    end
+
+    expect { brew "list" }
+      .to output("#{formulae.join("\n")}\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/log_spec.rb b/Library/Homebrew/test/cmd/log_spec.rb
new file mode 100644
index 000000000..bdbca8912
--- /dev/null
+++ b/Library/Homebrew/test/cmd/log_spec.rb
@@ -0,0 +1,41 @@
+describe "brew log", :integration_test do
+  it "shows the Git log for the Homebrew repository when no argument is given" do
+    HOMEBREW_REPOSITORY.cd do
+      shutup do
+        system "git", "init"
+        system "git", "commit", "--allow-empty", "-m", "This is a test commit"
+      end
+    end
+
+    expect { brew "log" }
+      .to output(/This is a test commit/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "shows the Git log for a given Formula" do
+    setup_test_formula "testball"
+
+    core_tap = CoreTap.new
+    core_tap.path.cd do
+      shutup do
+        system "git", "init"
+        system "git", "add", "--all"
+        system "git", "commit", "-m", "This is a test commit for Testball"
+      end
+    end
+
+    core_tap_url = "file://#{core_tap.path}"
+    shallow_tap = Tap.fetch("homebrew", "shallow")
+    shutup do
+      system "git", "clone", "--depth=1", core_tap_url, shallow_tap.path
+    end
+
+    expect { brew "log", "#{shallow_tap}/testball" }
+      .to output(/This is a test commit for Testball/).to_stdout
+      .and output(/Warning: The git repository is a shallow clone/).to_stderr
+      .and be_a_success
+
+    expect(shallow_tap.path/".git/shallow").to exist, "A shallow clone should have been created."
+  end
+end
diff --git a/Library/Homebrew/test/cmd/migrate_spec.rb b/Library/Homebrew/test/cmd/migrate_spec.rb
new file mode 100644
index 000000000..18c94fa01
--- /dev/null
+++ b/Library/Homebrew/test/cmd/migrate_spec.rb
@@ -0,0 +1,46 @@
+describe "brew migrate", :integration_test do
+  before(:each) do
+    setup_test_formula "testball1"
+    setup_test_formula "testball2"
+  end
+
+  it "fails when no argument is given" do
+    expect { brew "migrate" }
+      .to output(/Invalid usage/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+  end
+
+  it "fails when a given Formula doesn't exist" do
+    expect { brew "migrate", "testball" }
+      .to output(/No available formula with the name "testball"/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+  end
+
+  it "fails if a given Formula doesn't replace another one" do
+    expect { brew "migrate", "testball1" }
+      .to output(/testball1 doesn't replace any formula/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+  end
+
+  it "migrates a renamed Formula" do
+    install_and_rename_coretap_formula "testball1", "testball2"
+
+    expect { brew "migrate", "testball1" }
+      .to output(/Migrating testball1 to testball2/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "fails if a given Formula is not installed" do
+    install_and_rename_coretap_formula "testball1", "testball2"
+    (HOMEBREW_CELLAR/"testball1").rmtree
+
+    expect { brew "migrate", "testball1" }
+      .to output(/Error: No such keg/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+  end
+end
diff --git a/Library/Homebrew/test/cmd/missing_spec.rb b/Library/Homebrew/test/cmd/missing_spec.rb
new file mode 100644
index 000000000..4668e72e0
--- /dev/null
+++ b/Library/Homebrew/test/cmd/missing_spec.rb
@@ -0,0 +1,41 @@
+describe "brew missing", :integration_test do
+  before(:each) do
+    setup_test_formula "foo"
+    setup_test_formula "bar"
+  end
+
+  def make_prefix(name)
+    (HOMEBREW_CELLAR/name/"1.0").mkpath
+  end
+
+  it "prints missing dependencies" do
+    make_prefix "bar"
+
+    expect { brew "missing" }
+      .to output("foo\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "prints nothing if all dependencies are installed" do
+    make_prefix "foo"
+    make_prefix "bar"
+
+    expect { brew "missing" }
+      .to be_a_success
+      .and not_to_output.to_stdout
+      .and not_to_output.to_stderr
+  end
+
+  describe "--hide=" do
+    it "pretends that the specified Formulae are not installed" do
+      make_prefix "foo"
+      make_prefix "bar"
+
+      expect { brew "missing", "--hide=foo" }
+        .to output("bar: foo\n").to_stdout
+        .and not_to_output.to_stderr
+        .and be_a_success
+    end
+  end
+end
diff --git a/Library/Homebrew/test/cmd/options_spec.rb b/Library/Homebrew/test/cmd/options_spec.rb
new file mode 100644
index 000000000..33fe8b107
--- /dev/null
+++ b/Library/Homebrew/test/cmd/options_spec.rb
@@ -0,0 +1,12 @@
+describe "brew options", :integration_test do
+  it "prints a given Formula's options" do
+    setup_test_formula "testball", <<-EOS.undent
+      depends_on "bar" => :recommended
+    EOS
+
+    expect { brew "options", "testball" }
+      .to output("--with-foo\n\tBuild with foo\n--without-bar\n\tBuild without bar support\n\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/outdated_spec.rb b/Library/Homebrew/test/cmd/outdated_spec.rb
new file mode 100644
index 000000000..2ce0825e8
--- /dev/null
+++ b/Library/Homebrew/test/cmd/outdated_spec.rb
@@ -0,0 +1,11 @@
+describe "brew outdated", :integration_test do
+  it "prints outdated Formulae" do
+    setup_test_formula "testball"
+    (HOMEBREW_CELLAR/"testball/0.0.1/foo").mkpath
+
+    expect { brew "outdated" }
+      .to output("testball\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/pin_spec.rb b/Library/Homebrew/test/cmd/pin_spec.rb
new file mode 100644
index 000000000..9ffc052c3
--- /dev/null
+++ b/Library/Homebrew/test/cmd/pin_spec.rb
@@ -0,0 +1,13 @@
+describe "brew pin", :integration_test do
+  it "pins a Formula's version" do
+    setup_test_formula "testball"
+    (HOMEBREW_CELLAR/"testball/0.0.1/foo").mkpath
+
+    shutup do
+      expect { brew "pin", "testball" }.to be_a_success
+      expect { brew "upgrade" }.to be_a_success
+    end
+
+    expect(HOMEBREW_CELLAR/"testball/0.1").not_to be_a_directory
+  end
+end
diff --git a/Library/Homebrew/test/cmd/prune_spec.rb b/Library/Homebrew/test/cmd/prune_spec.rb
new file mode 100644
index 000000000..c5a9df70c
--- /dev/null
+++ b/Library/Homebrew/test/cmd/prune_spec.rb
@@ -0,0 +1,28 @@
+describe "brew prune", :integration_test do
+  it "removes empty directories and broken symlinks" do
+    share = (HOMEBREW_PREFIX/"share")
+
+    (share/"pruneable/directory/here").mkpath
+    (share/"notpruneable/file").write "I'm here"
+    FileUtils.ln_s "/i/dont/exist/no/really/i/dont", share/"pruneable_symlink"
+
+    expect { brew "prune", "--dry-run" }
+      .to output(%r{Would remove \(empty directory\): .*/pruneable/directory/here}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "prune" }
+      .to output(/Pruned 1 symbolic links and 3 directories/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect(share/"pruneable").not_to be_a_directory
+    expect(share/"notpruneable").to be_a_directory
+    expect(share/"pruneable_symlink").not_to be_a_symlink
+
+    expect { brew "prune", "--verbose" }
+      .to output(/Nothing pruned/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/readall_spec.rb b/Library/Homebrew/test/cmd/readall_spec.rb
new file mode 100644
index 000000000..9165e0cb0
--- /dev/null
+++ b/Library/Homebrew/test/cmd/readall_spec.rb
@@ -0,0 +1,20 @@
+describe "brew readall", :integration_test do
+  it "imports all Formulae for a given Tap" do
+    formula_file = setup_test_formula "testball"
+
+    alias_file = CoreTap.new.alias_dir/"foobar"
+    alias_file.parent.mkpath
+
+    FileUtils.ln_s formula_file, alias_file
+
+    expect { brew "readall", "--aliases", "--syntax" }
+      .to be_a_success
+      .and not_to_output.to_stdout
+      .and not_to_output.to_stderr
+
+    expect { brew "readall", "homebrew/core" }
+      .to be_a_success
+      .and not_to_output.to_stdout
+      .and not_to_output.to_stderr
+  end
+end
diff --git a/Library/Homebrew/test/cmd/reinstall_spec.rb b/Library/Homebrew/test/cmd/reinstall_spec.rb
new file mode 100644
index 000000000..63584e6be
--- /dev/null
+++ b/Library/Homebrew/test/cmd/reinstall_spec.rb
@@ -0,0 +1,44 @@
+require "extend/ENV"
+
+describe "brew reinstall", :integration_test do
+  before(:each) do
+    setup_test_formula "testball"
+
+    shutup do
+      expect { brew "install", "testball", "--with-foo" }.to be_a_success
+    end
+  end
+
+  it "reinstalls a Formula" do
+    foo_dir = HOMEBREW_CELLAR/"testball/0.1/foo"
+    expect(foo_dir).to exist
+    foo_dir.rmtree
+
+    expect { brew "reinstall", "testball" }
+      .to output(/Reinstalling testball --with-foo/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect(foo_dir).to exist
+  end
+
+  it "reinstalls a Formula even when one of the options is invalid" do
+    expect { brew "reinstall", "testball", "--with-fo" }
+      .to output(/Reinstalling testball --with-foo/).to_stdout
+      .and output(/testball: this formula has no \-\-with-fo option so it will be ignored!/).to_stderr
+      .and be_a_success
+  end
+
+  it "refuses to reinstall a pinned Formula, but doesn't fail" do
+    (HOMEBREW_CELLAR/"testball/0.1").mkpath
+    HOMEBREW_PINNED_KEGS.mkpath
+    FileUtils.ln_s HOMEBREW_CELLAR/"testball/0.1", HOMEBREW_PINNED_KEGS/"testball"
+
+    expect { brew "reinstall", "testball" }
+      .to output(/testball is pinned. You must unpin it to reinstall./).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_success
+
+    HOMEBREW_PINNED_KEGS.rmtree
+  end
+end
diff --git a/Library/Homebrew/test/cmd/search_remote_tap_spec.rb b/Library/Homebrew/test/cmd/search_remote_tap_spec.rb
new file mode 100644
index 000000000..99c2cc20b
--- /dev/null
+++ b/Library/Homebrew/test/cmd/search_remote_tap_spec.rb
@@ -0,0 +1,19 @@
+require "cmd/search"
+
+describe Homebrew do
+  specify "#search_tap" do
+    json_response = {
+      "tree" => [
+        {
+          "path" => "Formula/not-a-formula.rb",
+          "type" => "blob",
+        },
+      ],
+    }
+
+    allow(GitHub).to receive(:open).and_yield(json_response)
+
+    expect(described_class.search_tap("homebrew", "not-a-tap", "not-a-formula"))
+      .to eq(["homebrew/not-a-tap/not-a-formula"])
+  end
+end
diff --git a/Library/Homebrew/test/cmd/search_spec.rb b/Library/Homebrew/test/cmd/search_spec.rb
new file mode 100644
index 000000000..06b7073d8
--- /dev/null
+++ b/Library/Homebrew/test/cmd/search_spec.rb
@@ -0,0 +1,57 @@
+describe "brew search", :integration_test do
+  before(:each) do
+    setup_test_formula "testball"
+  end
+
+  it "lists all available Formulae when no argument is given" do
+    expect { brew "search" }
+      .to output(/testball/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "supports searching by name" do
+    expect { brew "search", "testball" }
+      .to output(/testball/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  it "supports searching a fully-qualified name " do
+    expect { brew "search", "homebrew/homebrew-core/testball" }
+      .to output(/testball/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+
+  describe "--desc" do
+    let(:desc_cache) { HOMEBREW_CACHE/"desc_cache.json" }
+
+    it "supports searching in descriptions and creates a description cache" do
+      expect(desc_cache).not_to exist
+
+      expect { brew "search", "--desc", "Some test" }
+        .to output(/testball/).to_stdout
+        .and not_to_output.to_stderr
+        .and be_a_success
+
+      expect(desc_cache).to exist
+    end
+  end
+
+  {
+    "macports" => "https://www.macports.org/ports.php?by=name&substr=testball",
+    "fink" => "http://pdb.finkproject.org/pdb/browse.php?summary=testball",
+    "debian" => "https://packages.debian.org/search?keywords=testball&searchon=names&suite=all&section=all",
+    "opensuse" => "https://software.opensuse.org/search?q=testball",
+    "fedora" => "https://admin.fedoraproject.org/pkgdb/packages/%2Atestball%2A/",
+    "ubuntu" => "http://packages.ubuntu.com/search?keywords=testball&searchon=names&suite=all&section=all",
+  }.each do |flag, url|
+    specify "--#{flag}" do
+      expect { brew "search", "--#{flag}", "testball", "HOMEBREW_BROWSER" => "echo" }
+        .to output("#{url}\n").to_stdout
+        .and not_to_output.to_stderr
+        .and be_a_success
+    end
+  end
+end
diff --git a/Library/Homebrew/test/cmd/services_spec.rb b/Library/Homebrew/test/cmd/services_spec.rb
new file mode 100644
index 000000000..c456fea17
--- /dev/null
+++ b/Library/Homebrew/test/cmd/services_spec.rb
@@ -0,0 +1,10 @@
+describe "brew services", :integration_test, :needs_macos, :needs_official_cmd_taps do
+  it "allows controlling services" do
+    setup_remote_tap "homebrew/services"
+
+    expect { brew "services", "list" }
+      .to output("Warning: No services available to control with `brew services`\n").to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/sh_spec.rb b/Library/Homebrew/test/cmd/sh_spec.rb
new file mode 100644
index 000000000..5260ddb75
--- /dev/null
+++ b/Library/Homebrew/test/cmd/sh_spec.rb
@@ -0,0 +1,8 @@
+describe "brew sh", :integration_test do
+  it "runs a shell with the Homebrew environment" do
+    expect { brew "sh", "SHELL" => which("true") }
+      .to output(/Your shell has been configured/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/switch_spec.rb b/Library/Homebrew/test/cmd/switch_spec.rb
new file mode 100644
index 000000000..c27c96c14
--- /dev/null
+++ b/Library/Homebrew/test/cmd/switch_spec.rb
@@ -0,0 +1,34 @@
+describe "brew switch", :integration_test do
+  it "allows switching between Formula versions" do
+    expect { brew "switch" }
+      .to output(/Usage: brew switch <name> <version>/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+
+    expect { brew "switch", "testball", "0.1" }
+      .to output(/testball not found/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+
+    setup_test_formula "testball", <<-EOS.undent
+      keg_only "just because"
+    EOS
+
+    shutup do
+      expect { brew "install", "testball" }.to be_a_success
+    end
+
+    testball_rack = HOMEBREW_CELLAR/"testball"
+    FileUtils.cp_r testball_rack/"0.1", testball_rack/"0.2"
+
+    expect { brew "switch", "testball", "0.2" }
+      .to output(/link created/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "switch", "testball", "0.3" }
+      .to output("Versions available: 0.1, 0.2\n").to_stdout
+      .and output(/testball does not have a version "0.3"/).to_stderr
+      .and be_a_failure
+  end
+end
diff --git a/Library/Homebrew/test/cmd/tap-new_spec.rb b/Library/Homebrew/test/cmd/tap-new_spec.rb
new file mode 100644
index 000000000..ea4b8aa73
--- /dev/null
+++ b/Library/Homebrew/test/cmd/tap-new_spec.rb
@@ -0,0 +1,10 @@
+describe "brew tap-new", :integration_test do
+  it "initializes a new Tap with a ReadMe file" do
+    expect { brew "tap-new", "homebrew/foo", "--verbose" }
+      .to be_a_success
+      .and not_to_output.to_stdout
+      .and not_to_output.to_stderr
+
+    expect(HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-foo/README.md").to exist
+  end
+end
diff --git a/Library/Homebrew/test/cmd/uninstall_spec.rb b/Library/Homebrew/test/cmd/uninstall_spec.rb
new file mode 100644
index 000000000..65f69e802
--- /dev/null
+++ b/Library/Homebrew/test/cmd/uninstall_spec.rb
@@ -0,0 +1,12 @@
+describe "brew uninstall", :integration_test do
+  it "uninstalls a given Formula" do
+    shutup do
+      expect { brew "install", testball }.to be_a_success
+    end
+
+    expect { brew "uninstall", "--force", testball }
+      .to output(/Uninstalling testball/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/unlink_spec.rb b/Library/Homebrew/test/cmd/unlink_spec.rb
new file mode 100644
index 000000000..5961651fe
--- /dev/null
+++ b/Library/Homebrew/test/cmd/unlink_spec.rb
@@ -0,0 +1,14 @@
+describe "brew unlink", :integration_test do
+  it "unlinks a Formula" do
+    setup_test_formula "testball"
+
+    shutup do
+      expect { brew "install", "testball" }.to be_a_success
+    end
+
+    expect { brew "unlink", "--dry-run", "testball" }
+      .to output(/Would remove/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/unlinkapps_spec.rb b/Library/Homebrew/test/cmd/unlinkapps_spec.rb
new file mode 100644
index 000000000..1e21bd851
--- /dev/null
+++ b/Library/Homebrew/test/cmd/unlinkapps_spec.rb
@@ -0,0 +1,24 @@
+describe "brew unlinkapps", :integration_test do
+  let(:home_dir) { @home_dir = Pathname.new(Dir.mktmpdir) }
+  let(:apps_dir) { home_dir/"Applications" }
+
+  after(:each) do
+    home_dir.rmtree unless @home_dir.nil?
+  end
+
+  it "unlinks symlinked applications" do
+    apps_dir.mkpath
+
+    setup_test_formula "testball"
+
+    source_app = HOMEBREW_CELLAR/"testball/0.1/TestBall.app"
+    source_app.mkpath
+
+    FileUtils.ln_s source_app, apps_dir/"TestBall.app"
+
+    expect { brew "unlinkapps", "--local", "HOME" => home_dir }
+      .to output(%r{Unlinking: #{Regexp.escape(apps_dir)}/TestBall.app}).to_stdout
+      .and output(/`brew unlinkapps` has been deprecated/).to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/cmd/unpack_spec.rb b/Library/Homebrew/test/cmd/unpack_spec.rb
new file mode 100644
index 000000000..244fc0852
--- /dev/null
+++ b/Library/Homebrew/test/cmd/unpack_spec.rb
@@ -0,0 +1,16 @@
+describe "brew unpack", :integration_test do
+  it "unpacks a given Formula's archive" do
+    setup_test_formula "testball"
+
+    Dir.mktmpdir do |path|
+      path = Pathname.new(path)
+
+      shutup do
+        expect { brew "unpack", "testball", "--destdir=#{path}" }
+          .to be_a_success
+      end
+
+      expect(path/"testball-0.1").to be_a_directory
+    end
+  end
+end
diff --git a/Library/Homebrew/test/cmd/unpin_spec.rb b/Library/Homebrew/test/cmd/unpin_spec.rb
new file mode 100644
index 000000000..4f14626d8
--- /dev/null
+++ b/Library/Homebrew/test/cmd/unpin_spec.rb
@@ -0,0 +1,14 @@
+describe "brew unpin", :integration_test do
+  it "unpins a Formula's version" do
+    setup_test_formula "testball"
+    (HOMEBREW_CELLAR/"testball/0.0.1/foo").mkpath
+
+    shutup do
+      expect { brew "pin", "testball" }.to be_a_success
+      expect { brew "unpin", "testball" }.to be_a_success
+      expect { brew "upgrade" }.to be_a_success
+    end
+
+    expect(HOMEBREW_CELLAR/"testball/0.1").to be_a_directory
+  end
+end
diff --git a/Library/Homebrew/test/cmd/update-report_spec.rb b/Library/Homebrew/test/cmd/update-report_spec.rb
new file mode 100644
index 000000000..3665e3c78
--- /dev/null
+++ b/Library/Homebrew/test/cmd/update-report_spec.rb
@@ -0,0 +1,127 @@
+require "cmd/update-report"
+require "formula_versions"
+require "yaml"
+
+describe Reporter do
+  def perform_update(fixture_name = "")
+    allow(Formulary).to receive(:factory).and_return(double(pkg_version: "1.0"))
+    allow(FormulaVersions).to receive(:new).and_return(double(formula_at_revision: "2.0"))
+
+    diff = YAML.load_file("#{TEST_FIXTURE_DIR}/updater_fixture.yaml")[fixture_name]
+    allow(subject).to receive(:diff).and_return(diff || "")
+
+    hub.add(subject) if subject.updated?
+  end
+
+  let(:reporter_class) do
+    Class.new(described_class) do
+      def initialize(tap)
+        @tap = tap
+
+        ENV["HOMEBREW_UPDATE_BEFORE#{repo_var}"] = "12345678"
+        ENV["HOMEBREW_UPDATE_AFTER#{repo_var}"] = "abcdef00"
+
+        super(tap)
+      end
+    end
+  end
+  subject { reporter_class.new(tap) }
+  let(:tap) { CoreTap.new }
+  let(:hub) { ReporterHub.new }
+
+  specify "without revision variable" do
+    ENV.delete_if { |k, _v| k.start_with? "HOMEBREW_UPDATE" }
+
+    expect {
+      described_class.new(tap)
+    }.to raise_error(Reporter::ReporterRevisionUnsetError)
+  end
+
+  specify "without any changes" do
+    perform_update
+    expect(hub).to be_empty
+  end
+
+  specify "without Formula changes" do
+    perform_update("update_git_diff_output_without_formulae_changes")
+
+    expect(hub.select_formula(:M)).to be_empty
+    expect(hub.select_formula(:A)).to be_empty
+    expect(hub.select_formula(:D)).to be_empty
+  end
+
+  specify "with Formula changes" do
+    perform_update("update_git_diff_output_with_formulae_changes")
+
+    expect(hub.select_formula(:M)).to eq(%w[xar yajl])
+    expect(hub.select_formula(:A)).to eq(%w[antiword bash-completion ddrescue dict lua])
+  end
+
+  specify "with removed Formulae" do
+    perform_update("update_git_diff_output_with_removed_formulae")
+
+    expect(hub.select_formula(:D)).to eq(%w[libgsasl])
+  end
+
+  specify "with changed file type" do
+    perform_update("update_git_diff_output_with_changed_filetype")
+
+    expect(hub.select_formula(:M)).to eq(%w[elixir])
+    expect(hub.select_formula(:A)).to eq(%w[libbson])
+    expect(hub.select_formula(:D)).to eq(%w[libgsasl])
+  end
+
+  specify "with renamed Formula" do
+    allow(tap).to receive(:formula_renames).and_return("cv" => "progress")
+    perform_update("update_git_diff_output_with_formula_rename")
+
+    expect(hub.select_formula(:A)).to be_empty
+    expect(hub.select_formula(:D)).to be_empty
+    expect(hub.select_formula(:R)).to eq([["cv", "progress"]])
+  end
+
+  context "when updating a Tap other than the core Tap" do
+    let(:tap) { Tap.new("foo", "bar") }
+
+    before(:each) do
+      (tap.path/"Formula").mkpath
+    end
+
+    after(:each) do
+      tap.path.parent.rmtree
+    end
+
+    specify "with restructured Tap" do
+      perform_update("update_git_diff_output_with_restructured_tap")
+
+      expect(hub.select_formula(:A)).to be_empty
+      expect(hub.select_formula(:D)).to be_empty
+      expect(hub.select_formula(:R)).to be_empty
+    end
+
+    specify "with renamed Formula and restructured Tap" do
+      allow(tap).to receive(:formula_renames).and_return("xchat" => "xchat2")
+      perform_update("update_git_diff_output_with_formula_rename_and_restructuring")
+
+      expect(hub.select_formula(:A)).to be_empty
+      expect(hub.select_formula(:D)).to be_empty
+      expect(hub.select_formula(:R)).to eq([%w[foo/bar/xchat foo/bar/xchat2]])
+    end
+
+    specify "with simulated 'homebrew/php' restructuring" do
+      perform_update("update_git_diff_simulate_homebrew_php_restructuring")
+
+      expect(hub.select_formula(:A)).to be_empty
+      expect(hub.select_formula(:D)).to be_empty
+      expect(hub.select_formula(:R)).to be_empty
+    end
+
+    specify "with Formula changes" do
+      perform_update("update_git_diff_output_with_tap_formulae_changes")
+
+      expect(hub.select_formula(:A)).to eq(%w[foo/bar/lua])
+      expect(hub.select_formula(:M)).to eq(%w[foo/bar/git])
+      expect(hub.select_formula(:D)).to be_empty
+    end
+  end
+end
diff --git a/Library/Homebrew/test/cmd/upgrade_spec.rb b/Library/Homebrew/test/cmd/upgrade_spec.rb
new file mode 100644
index 000000000..84f5c09f4
--- /dev/null
+++ b/Library/Homebrew/test/cmd/upgrade_spec.rb
@@ -0,0 +1,12 @@
+describe "brew upgrade", :integration_test do
+  it "upgrades a Formula to the latest version" do
+    setup_test_formula "testball"
+    (HOMEBREW_CELLAR/"testball/0.0.1/foo").mkpath
+
+    shutup do
+      expect { brew "upgrade" }.to be_a_success
+    end
+
+    expect(HOMEBREW_CELLAR/"testball/0.1").to be_a_directory
+  end
+end
diff --git a/Library/Homebrew/test/cmd/uses_spec.rb b/Library/Homebrew/test/cmd/uses_spec.rb
new file mode 100644
index 000000000..2a6f48cb7
--- /dev/null
+++ b/Library/Homebrew/test/cmd/uses_spec.rb
@@ -0,0 +1,25 @@
+describe "brew uses", :integration_test do
+  it "prints the Formulae a given Formula is used by" do
+    setup_test_formula "foo"
+    setup_test_formula "bar"
+    setup_test_formula "baz", <<-EOS.undent
+      url "https://example.com/baz-1.0"
+      depends_on "bar"
+    EOS
+
+    expect { brew "uses", "baz" }
+      .to be_a_success
+      .and not_to_output.to_stdout
+      .and not_to_output.to_stderr
+
+    expect { brew "uses", "bar" }
+      .to output("baz\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "uses", "--recursive", "foo" }
+      .to output(/(bar\nbaz|baz\nbar)/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/command_test.rb b/Library/Homebrew/test/command_test.rb
deleted file mode 100644
index d5c7aaa88..000000000
--- a/Library/Homebrew/test/command_test.rb
+++ /dev/null
@@ -1,11 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestCommand < IntegrationCommandTestCase
-  def test_command
-    assert_equal "#{HOMEBREW_LIBRARY_PATH}/cmd/info.rb",
-                 cmd("command", "info")
-
-    assert_match "Unknown command",
-                 cmd_fail("command", "I-don't-exist")
-  end
-end
diff --git a/Library/Homebrew/test/commands_test.rb b/Library/Homebrew/test/commands_test.rb
index d44d2da0e..da88ee2d5 100644
--- a/Library/Homebrew/test/commands_test.rb
+++ b/Library/Homebrew/test/commands_test.rb
@@ -4,15 +4,9 @@ require "cmd/commands"
 require "fileutils"
 require "testing_env"
 
-class IntegrationCommandTestCommands < IntegrationCommandTestCase
-  def test_commands
-    assert_match "Built-in commands",
-                 cmd("commands")
-  end
-end
-
 class CommandsTests < Homebrew::TestCase
   def setup
+    super
     @cmds = [
       # internal commands
       HOMEBREW_LIBRARY_PATH/"cmd/rbcmd.rb",
@@ -28,6 +22,7 @@ class CommandsTests < Homebrew::TestCase
 
   def teardown
     @cmds.each(&:unlink)
+    super
   end
 
   def test_internal_commands
@@ -45,8 +40,6 @@ class CommandsTests < Homebrew::TestCase
   end
 
   def test_external_commands
-    env = ENV.to_hash
-
     mktmpdir do |dir|
       %w[brew-t1 brew-t2.rb brew-t3.py].each do |file|
         path = "#{dir}/#{file}"
@@ -65,8 +58,6 @@ class CommandsTests < Homebrew::TestCase
         "Executable files with a non Ruby extension shoudn't be included"
       refute cmds.include?("t4"), "Non-executable files shouldn't be included"
     end
-  ensure
-    ENV.replace(env)
   end
 
   def test_internal_command_path
diff --git a/Library/Homebrew/test/compiler_failure_spec.rb b/Library/Homebrew/test/compiler_failure_spec.rb
new file mode 100644
index 000000000..b4fab0b27
--- /dev/null
+++ b/Library/Homebrew/test/compiler_failure_spec.rb
@@ -0,0 +1,37 @@
+require "compilers"
+
+RSpec::Matchers.alias_matcher :fail_with, :be_fails_with
+
+describe CompilerFailure do
+  describe "::create" do
+    it "creates a failure when given a symbol" do
+      failure = described_class.create(:clang)
+      expect(failure).to fail_with(double("Compiler", name: :clang, version: 425))
+    end
+
+    it "can be given a build number in a block" do
+      failure = described_class.create(:clang) { build 211 }
+      expect(failure).to fail_with(double("Compiler", name: :clang, version: 210))
+      expect(failure).not_to fail_with(double("Compiler", name: :clang, version: 318))
+    end
+
+    it "can be given an empty block" do
+      failure = described_class.create(:clang) {}
+      expect(failure).to fail_with(double("Compiler", name: :clang, version: 425))
+    end
+
+    it "creates a failure when given a hash" do
+      failure = described_class.create(gcc: "4.8")
+      expect(failure).to fail_with(double("Compiler", name: "gcc-4.8", version: "4.8"))
+      expect(failure).to fail_with(double("Compiler", name: "gcc-4.8", version: "4.8.1"))
+      expect(failure).not_to fail_with(double("Compiler", name: "gcc-4.7", version: "4.7"))
+    end
+
+    it "creates a failure when given a hash and a block with aversion" do
+      failure = described_class.create(gcc: "4.8") { version "4.8.1" }
+      expect(failure).to fail_with(double("Compiler", name: "gcc-4.8", version: "4.8"))
+      expect(failure).to fail_with(double("Compiler", name: "gcc-4.8", version: "4.8.1"))
+      expect(failure).not_to fail_with(double("Compiler", name: "gcc-4.8", version: "4.8.2"))
+    end
+  end
+end
diff --git a/Library/Homebrew/test/compiler_failure_test.rb b/Library/Homebrew/test/compiler_failure_test.rb
deleted file mode 100644
index c0b74d128..000000000
--- a/Library/Homebrew/test/compiler_failure_test.rb
+++ /dev/null
@@ -1,52 +0,0 @@
-require "testing_env"
-require "compilers"
-
-class CompilerFailureTests < Homebrew::TestCase
-  Compiler = Struct.new(:name, :version)
-
-  def assert_fails_with(compiler, failure)
-    assert_operator failure, :fails_with?, compiler
-  end
-
-  def refute_fails_with(compiler, failure)
-    refute_operator failure, :fails_with?, compiler
-  end
-
-  def compiler(name, version)
-    Compiler.new(name, version)
-  end
-
-  def create(spec, &block)
-    CompilerFailure.create(spec, &block)
-  end
-
-  def test_create_with_symbol
-    failure = create(:clang)
-    assert_fails_with compiler(:clang, 425), failure
-  end
-
-  def test_create_with_block
-    failure = create(:clang) { build 211 }
-    assert_fails_with compiler(:clang, 210), failure
-    refute_fails_with compiler(:clang, 318), failure
-  end
-
-  def test_create_with_block_without_build
-    failure = create(:clang) {}
-    assert_fails_with compiler(:clang, 425), failure
-  end
-
-  def test_create_with_hash
-    failure = create(gcc: "4.8")
-    assert_fails_with compiler("gcc-4.8", "4.8"), failure
-    assert_fails_with compiler("gcc-4.8", "4.8.1"), failure
-    refute_fails_with compiler("gcc-4.7", "4.7"), failure
-  end
-
-  def test_create_with_hash_and_version
-    failure = create(gcc: "4.8") { version "4.8.1" }
-    assert_fails_with compiler("gcc-4.8", "4.8"), failure
-    assert_fails_with compiler("gcc-4.8", "4.8.1"), failure
-    refute_fails_with compiler("gcc-4.8", "4.8.2"), failure
-  end
-end
diff --git a/Library/Homebrew/test/compiler_selector_spec.rb b/Library/Homebrew/test/compiler_selector_spec.rb
new file mode 100644
index 000000000..0f6f6b5f2
--- /dev/null
+++ b/Library/Homebrew/test/compiler_selector_spec.rb
@@ -0,0 +1,122 @@
+require "compilers"
+require "software_spec"
+
+describe CompilerSelector do
+  subject { described_class.new(software_spec, versions, compilers) }
+  let(:compilers) { [:clang, :gcc, :llvm, :gnu] }
+  let(:software_spec) { SoftwareSpec.new }
+  let(:cc) { :clang }
+  let(:versions) do
+    double(
+      gcc_4_0_build_version: Version::NULL,
+      gcc_build_version: Version.create("5666"),
+      llvm_build_version: Version::NULL,
+      clang_build_version: Version.create("425"),
+    )
+  end
+
+  before(:each) do
+    allow(versions).to receive(:non_apple_gcc_version) do |name|
+      case name
+      when "gcc-4.8" then Version.create("4.8.1")
+      when "gcc-4.7" then Version.create("4.7.1")
+      else Version::NULL
+      end
+    end
+  end
+
+  describe "#compiler" do
+    it "raises an error if no matching compiler can be found" do
+      software_spec.fails_with(:clang)
+      software_spec.fails_with(:llvm)
+      software_spec.fails_with(:gcc)
+      software_spec.fails_with(gcc: "4.8")
+      software_spec.fails_with(gcc: "4.7")
+
+      expect { subject.compiler }.to raise_error(CompilerSelectionError)
+    end
+
+    it "defaults to cc" do
+      expect(subject.compiler).to eq(cc)
+    end
+
+    it "returns gcc if it fails with clang" do
+      software_spec.fails_with(:clang)
+      expect(subject.compiler).to eq(:gcc)
+    end
+
+    it "returns clang if it fails with llvm" do
+      software_spec.fails_with(:llvm)
+      expect(subject.compiler).to eq(:clang)
+    end
+
+    it "returns clang if it fails with gcc" do
+      software_spec.fails_with(:gcc)
+      expect(subject.compiler).to eq(:clang)
+    end
+
+    it "returns clang if it fails with non-Apple gcc" do
+      software_spec.fails_with(gcc: "4.8")
+      expect(subject.compiler).to eq(:clang)
+    end
+
+    it "still returns gcc-4.8 if it fails with gcc without a specific version" do
+      software_spec.fails_with(:clang)
+      software_spec.fails_with(:gcc)
+      expect(subject.compiler).to eq("gcc-4.8")
+    end
+
+    it "returns gcc if it fails with clang and llvm" do
+      software_spec.fails_with(:clang)
+      software_spec.fails_with(:llvm)
+      expect(subject.compiler).to eq(:gcc)
+    end
+
+    it "returns clang if it fails with gcc and llvm" do
+      software_spec.fails_with(:gcc)
+      software_spec.fails_with(:llvm)
+      expect(subject.compiler).to eq(:clang)
+    end
+
+    example "returns gcc if it fails with a specific gcc version" do
+      software_spec.fails_with(:clang)
+      software_spec.fails_with(gcc: "4.8")
+      expect(subject.compiler).to eq(:gcc)
+    end
+
+    example "returns a lower version of gcc if it fails with the highest version" do
+      software_spec.fails_with(:clang)
+      software_spec.fails_with(:gcc)
+      software_spec.fails_with(:llvm)
+      software_spec.fails_with(gcc: "4.8")
+      expect(subject.compiler).to eq("gcc-4.7")
+    end
+
+    it "prefers gcc" do
+      software_spec.fails_with(:clang)
+      software_spec.fails_with(:gcc)
+      expect(subject.compiler).to eq("gcc-4.8")
+    end
+
+    it "raises an error when gcc is missing" do
+      allow(versions).to receive(:gcc_build_version).and_return(Version::NULL)
+
+      software_spec.fails_with(:clang)
+      software_spec.fails_with(:llvm)
+      software_spec.fails_with(gcc: "4.8")
+      software_spec.fails_with(gcc: "4.7")
+
+      expect { subject.compiler }.to raise_error(CompilerSelectionError)
+    end
+
+    it "raises an error when llvm and gcc are missing" do
+      allow(versions).to receive(:gcc_build_version).and_return(Version::NULL)
+
+      software_spec.fails_with(:clang)
+      software_spec.fails_with(gcc: "4.8")
+      software_spec.fails_with(gcc: "4.7")
+
+      expect { subject.compiler }.to raise_error(CompilerSelectionError)
+    end
+  end
+end
diff --git a/Library/Homebrew/test/compiler_selector_test.rb b/Library/Homebrew/test/compiler_selector_test.rb
deleted file mode 100644
index b1591bdbe..000000000
--- a/Library/Homebrew/test/compiler_selector_test.rb
+++ /dev/null
@@ -1,116 +0,0 @@
-require "testing_env"
-require "compilers"
-require "software_spec"
-
-class CompilerSelectorTests < Homebrew::TestCase
-  class Double < SoftwareSpec
-    def <<(cc)
-      fails_with(cc)
-      self
-    end
-  end
-
-  class CompilerVersions
-    attr_accessor :gcc_4_0_build_version, :gcc_build_version,
-      :clang_build_version
-
-    def initialize
-      @gcc_4_0_build_version = Version::NULL
-      @gcc_build_version = Version.create("5666")
-      @llvm_build_version = Version::NULL
-      @clang_build_version = Version.create("425")
-    end
-
-    def non_apple_gcc_version(name)
-      case name
-      when "gcc-4.8" then Version.create("4.8.1")
-      when "gcc-4.7" then Version.create("4.7.1")
-      else Version::NULL
-      end
-    end
-  end
-
-  def setup
-    @f  = Double.new
-    @cc = :clang
-    @versions = CompilerVersions.new
-    @selector = CompilerSelector.new(
-      @f, @versions, [:clang, :gcc, :llvm, :gnu]
-    )
-  end
-
-  def actual_cc
-    @selector.compiler
-  end
-
-  def test_all_compiler_failures
-    @f << :clang << :llvm << :gcc << { gcc: "4.8" } << { gcc: "4.7" }
-    assert_raises(CompilerSelectionError) { actual_cc }
-  end
-
-  def test_no_compiler_failures
-    assert_equal @cc, actual_cc
-  end
-
-  def test_fails_with_clang
-    @f << :clang
-    assert_equal :gcc, actual_cc
-  end
-
-  def test_fails_with_llvm
-    @f << :llvm
-    assert_equal :clang, actual_cc
-  end
-
-  def test_fails_with_gcc
-    @f << :gcc
-    assert_equal :clang, actual_cc
-  end
-
-  def test_fails_with_non_apple_gcc
-    @f << { gcc: "4.8" }
-    assert_equal :clang, actual_cc
-  end
-
-  def test_mixed_failures_1
-    @f << :clang << :gcc
-    assert_equal "gcc-4.8", actual_cc
-  end
-
-  def test_mixed_failures_2
-    @f << :clang << :llvm
-    assert_equal :gcc, actual_cc
-  end
-
-  def test_mixed_failures_3
-    @f << :gcc << :llvm
-    assert_equal :clang, actual_cc
-  end
-
-  def test_mixed_failures_4
-    @f << :clang << { gcc: "4.8" }
-    assert_equal :gcc, actual_cc
-  end
-
-  def test_mixed_failures_5
-    @f << :clang << :gcc << :llvm << { gcc: "4.8" }
-    assert_equal "gcc-4.7", actual_cc
-  end
-
-  def test_gcc_precedence
-    @f << :clang << :gcc
-    assert_equal "gcc-4.8", actual_cc
-  end
-
-  def test_missing_gcc
-    @versions.gcc_build_version = Version::NULL
-    @f << :clang << :llvm << { gcc: "4.8" } << { gcc: "4.7" }
-    assert_raises(CompilerSelectionError) { actual_cc }
-  end
-
-  def test_missing_llvm_and_gcc
-    @versions.gcc_build_version = Version::NULL
-    @f << :clang << { gcc: "4.8" } << { gcc: "4.7" }
-    assert_raises(CompilerSelectionError) { actual_cc }
-  end
-end
diff --git a/Library/Homebrew/test/config_test.rb b/Library/Homebrew/test/config_test.rb
deleted file mode 100644
index 81da4660a..000000000
--- a/Library/Homebrew/test/config_test.rb
+++ /dev/null
@@ -1,8 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestConfig < IntegrationCommandTestCase
-  def test_config
-    assert_match "HOMEBREW_VERSION: #{HOMEBREW_VERSION}",
-                 cmd("config")
-  end
-end
diff --git a/Library/Homebrew/test/create_test.rb b/Library/Homebrew/test/create_test.rb
deleted file mode 100644
index aeee428aa..000000000
--- a/Library/Homebrew/test/create_test.rb
+++ /dev/null
@@ -1,12 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestCreate < IntegrationCommandTestCase
-  def test_create
-    url = "file://#{TEST_FIXTURE_DIR}/tarballs/testball-0.1.tbz"
-    cmd("create", url, "HOMEBREW_EDITOR" => "/bin/cat")
-
-    formula_file = CoreTap.new.formula_dir/"testball.rb"
-    assert formula_file.exist?, "The formula source should have been created"
-    assert_match %Q(sha256 "#{TESTBALL_SHA256}"), formula_file.read
-  end
-end
diff --git a/Library/Homebrew/test/custom_command_test.rb b/Library/Homebrew/test/custom_command_test.rb
deleted file mode 100644
index 8d05bc6c7..000000000
--- a/Library/Homebrew/test/custom_command_test.rb
+++ /dev/null
@@ -1,18 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestCustomCommand < IntegrationCommandTestCase
-  def test_custom_command
-    mktmpdir do |path|
-      cmd = "int-test-#{rand}"
-      file = "#{path}/brew-#{cmd}"
-
-      File.open(file, "w") do |f|
-        f.write "#!/bin/sh\necho 'I am #{cmd}'\n"
-      end
-      FileUtils.chmod 0777, file
-
-      assert_match "I am #{cmd}",
-        cmd(cmd, "PATH" => "#{path}#{File::PATH_SEPARATOR}#{ENV["PATH"]}")
-    end
-  end
-end
diff --git a/Library/Homebrew/test/cxxstdlib_spec.rb b/Library/Homebrew/test/cxxstdlib_spec.rb
new file mode 100644
index 000000000..dd2e4e1c6
--- /dev/null
+++ b/Library/Homebrew/test/cxxstdlib_spec.rb
@@ -0,0 +1,68 @@
+require "formula"
+require "cxxstdlib"
+
+describe CxxStdlib do
+  let(:clang) { CxxStdlib.create(:libstdcxx, :clang) }
+  let(:gcc) { CxxStdlib.create(:libstdcxx, :gcc) }
+  let(:gcc40) { CxxStdlib.create(:libstdcxx, :gcc_4_0) }
+  let(:gcc42) { CxxStdlib.create(:libstdcxx, :gcc_4_2) }
+  let(:gcc48) { CxxStdlib.create(:libstdcxx, "gcc-4.8") }
+  let(:gcc49) { CxxStdlib.create(:libstdcxx, "gcc-4.9") }
+  let(:lcxx) { CxxStdlib.create(:libcxx, :clang) }
+  let(:purec) { CxxStdlib.create(nil, :clang) }
+
+  describe "#compatible_with?" do
+    specify "Apple libstdcxx intercompatibility" do
+      expect(clang).to be_compatible_with(gcc)
+      expect(clang).to be_compatible_with(gcc42)
+    end
+
+    specify "compatibility with itself" do
+      expect(gcc).to be_compatible_with(gcc)
+      expect(gcc48).to be_compatible_with(gcc48)
+      expect(clang).to be_compatible_with(clang)
+    end
+
+    specify "Apple/GNU libstdcxx incompatibility" do
+      expect(clang).not_to be_compatible_with(gcc48)
+      expect(gcc48).not_to be_compatible_with(clang)
+    end
+
+    specify "GNU cross-version incompatibility" do
+      expect(gcc48).not_to be_compatible_with(gcc49)
+      expect(gcc49).not_to be_compatible_with(gcc48)
+    end
+
+    specify "libstdcxx and libcxx incompatibility" do
+      expect(clang).not_to be_compatible_with(lcxx)
+      expect(lcxx).not_to be_compatible_with(clang)
+    end
+
+    specify "compatibility for non-cxx software" do
+      expect(purec).to be_compatible_with(clang)
+      expect(clang).to be_compatible_with(purec)
+      expect(purec).to be_compatible_with(purec)
+      expect(purec).to be_compatible_with(gcc48)
+      expect(gcc48).to be_compatible_with(purec)
+    end
+  end
+
+  describe "#apple_compiler?" do
+    it "returns true for Apple compilers" do
+      expect(clang).to be_an_apple_compiler
+      expect(gcc).to be_an_apple_compiler
+      expect(gcc42).to be_an_apple_compiler
+    end
+
+    it "returns false for non-Apple compilers" do
+      expect(gcc48).not_to be_an_apple_compiler
+    end
+  end
+
+  describe "#type_string" do
+    specify "formatting" do
+      expect(clang.type_string).to eq("libstdc++")
+      expect(lcxx.type_string).to eq("libc++")
+    end
+  end
+end
diff --git a/Library/Homebrew/test/dependencies_test.rb b/Library/Homebrew/test/dependencies_test.rb
index db3b78226..c5444fcbc 100644
--- a/Library/Homebrew/test/dependencies_test.rb
+++ b/Library/Homebrew/test/dependencies_test.rb
@@ -5,6 +5,7 @@ require "requirements"
 
 class DependenciesTests < Homebrew::TestCase
   def setup
+    super
     @deps = Dependencies.new
   end
 
@@ -89,6 +90,7 @@ end
 
 class RequirementsTests < Homebrew::TestCase
   def setup
+    super
     @reqs = Requirements.new
   end
 
diff --git a/Library/Homebrew/test/dependency_collector_test.rb b/Library/Homebrew/test/dependency_collector_test.rb
index 1c7f70118..c63d04637 100644
--- a/Library/Homebrew/test/dependency_collector_test.rb
+++ b/Library/Homebrew/test/dependency_collector_test.rb
@@ -11,11 +11,13 @@ class DependencyCollectorTests < Homebrew::TestCase
   end
 
   def setup
+    super
     @d = DependencyCollector.new
   end
 
   def teardown
     DependencyCollector.clear_cache
+    super
   end
 
   def test_dependency_creation
diff --git a/Library/Homebrew/test/dependency_expansion_spec.rb b/Library/Homebrew/test/dependency_expansion_spec.rb
new file mode 100644
index 000000000..f955237a9
--- /dev/null
+++ b/Library/Homebrew/test/dependency_expansion_spec.rb
@@ -0,0 +1,136 @@
+require "dependency"
+
+describe Dependency do
+  def build_dep(name, tags = [], deps = [])
+    dep = described_class.new(name.to_s, tags)
+    allow(dep).to receive(:to_formula).and_return(double(deps: deps, name: name))
+    dep
+  end
+
+  let(:foo) { build_dep(:foo) }
+  let(:bar) { build_dep(:bar) }
+  let(:baz) { build_dep(:baz) }
+  let(:qux) { build_dep(:qux) }
+  let(:deps) { [foo, bar, baz, qux] }
+  let(:formula) { double(deps: deps, name: "f") }
+
+  describe "::expand" do
+    it "yields dependent and dependency pairs" do
+      i = 0
+      described_class.expand(formula) do |dependent, dep|
+        expect(dependent).to eq(formula)
+        expect(deps[i]).to eq(dep)
+        i += 1
+      end
+    end
+
+    it "returns the dependencies" do
+      expect(described_class.expand(formula)).to eq(deps)
+    end
+
+    it "prunes all when given a block with ::prune" do
+      expect(described_class.expand(formula) { described_class.prune }).to be_empty
+    end
+
+    it "can prune selectively" do
+      deps = described_class.expand(formula) do |_, dep|
+        described_class.prune if dep.name == "foo"
+      end
+
+      expect(deps).to eq([bar, baz, qux])
+    end
+
+    it "preserves dependency order" do
+      allow(foo).to receive(:to_formula).and_return(double(name: "f", deps: [qux, baz]))
+      expect(described_class.expand(formula)).to eq([qux, baz, foo, bar])
+    end
+  end
+
+  it "skips optionals by default" do
+    deps = [build_dep(:foo, [:optional]), bar, baz, qux]
+    f = double(deps: deps, build: double(with?: false), name: "f")
+    expect(described_class.expand(f)).to eq([bar, baz, qux])
+  end
+
+  it "keeps recommended dependencies by default" do
+    deps = [build_dep(:foo, [:recommended]), bar, baz, qux]
+    f = double(deps: deps, build: double(with?: true), name: "f")
+    expect(described_class.expand(f)).to eq(deps)
+  end
+
+  it "merges repeated dependencies with differing options" do
+    foo2 = build_dep(:foo, ["option"])
+    baz2 = build_dep(:baz, ["option"])
+    deps << foo2 << baz2
+    deps = [foo2, bar, baz2, qux]
+    deps.zip(described_class.expand(formula)) do |expected, actual|
+      expect(expected.tags).to eq(actual.tags)
+      expect(expected).to eq(actual)
+    end
+  end
+
+  it "merges dependencies and perserves env_proc" do
+    env_proc = double
+    dep = described_class.new("foo", [], env_proc)
+    allow(dep).to receive(:to_formula).and_return(double(deps: [], name: "foo"))
+    deps.replace([dep])
+    expect(described_class.expand(formula).first.env_proc).to eq(env_proc)
+  end
+
+  it "merges tags without duplicating them" do
+    foo2 = build_dep(:foo, ["option"])
+    foo3 = build_dep(:foo, ["option"])
+    deps << foo2 << foo3
+
+    expect(described_class.expand(formula).first.tags).to eq(%w[option])
+  end
+
+  it "skips parent but yields children with ::skip" do
+    f = double(
+      name: "f",
+      deps: [
+        build_dep(:foo, [], [bar, baz]),
+        build_dep(:foo, [], [baz]),
+      ],
+    )
+
+    deps = described_class.expand(f) do |_dependent, dep|
+      described_class.skip if %w[foo qux].include? dep.name
+    end
+
+    expect(deps).to eq([bar, baz])
+  end
+
+  it "keeps dependency but prunes recursive dependencies with ::keep_but_prune_recursive_deps" do
+    foo = build_dep(:foo, [:build], bar)
+    baz = build_dep(:baz, [:build])
+    f = double(name: "f", deps: [foo, baz])
+
+    deps = described_class.expand(f) do |_dependent, dep|
+      described_class.keep_but_prune_recursive_deps if dep.build?
+    end
+
+    expect(deps).to eq([foo, baz])
+  end
+
+  it "returns only the dependencies given as a collection as second argument" do
+    expect(formula.deps).to eq([foo, bar, baz, qux])
+    expect(described_class.expand(formula, [bar, baz])).to eq([bar, baz])
+  end
+
+  it "doesn't raise an error when a dependency is cyclic" do
+    foo = build_dep(:foo)
+    bar = build_dep(:bar, [], [foo])
+    allow(foo).to receive(:to_formula).and_return(double(deps: [bar], name: foo.name))
+    f = double(name: "f", deps: [foo, bar])
+    expect { described_class.expand(f) }.not_to raise_error
+  end
+
+  it "cleans the expand stack" do
+    foo = build_dep(:foo)
+    allow(foo).to receive(:to_formula).and_raise(FormulaUnavailableError, foo.name)
+    f = double(name: "f", deps: [foo])
+    expect { described_class.expand(f) }.to raise_error(FormulaUnavailableError)
+    expect(described_class.instance_variable_get(:@expand_stack)).to be_empty
+  end
+end
diff --git a/Library/Homebrew/test/dependency_expansion_test.rb b/Library/Homebrew/test/dependency_expansion_test.rb
deleted file mode 100644
index 9d6de35e2..000000000
--- a/Library/Homebrew/test/dependency_expansion_test.rb
+++ /dev/null
@@ -1,137 +0,0 @@
-require "testing_env"
-require "dependency"
-
-class DependencyExpansionTests < Homebrew::TestCase
-  def build_dep(name, tags = [], deps = [])
-    dep = Dependency.new(name.to_s, tags)
-    dep.stubs(:to_formula).returns(stub(deps: deps, name: name))
-    dep
-  end
-
-  def setup
-    @foo = build_dep(:foo)
-    @bar = build_dep(:bar)
-    @baz = build_dep(:baz)
-    @qux = build_dep(:qux)
-    @deps = [@foo, @bar, @baz, @qux]
-    @f    = stub(deps: @deps, name: "f")
-  end
-
-  def test_expand_yields_dependent_and_dep_pairs
-    i = 0
-    Dependency.expand(@f) do |dependent, dep|
-      assert_equal @f, dependent
-      assert_equal dep, @deps[i]
-      i += 1
-    end
-  end
-
-  def test_expand_no_block
-    assert_equal @deps, Dependency.expand(@f)
-  end
-
-  def test_expand_prune_all
-    assert_empty Dependency.expand(@f) { Dependency.prune }
-  end
-
-  def test_expand_selective_pruning
-    deps = Dependency.expand(@f) do |_, dep|
-      Dependency.prune if dep.name == "foo"
-    end
-
-    assert_equal [@bar, @baz, @qux], deps
-  end
-
-  def test_expand_preserves_dependency_order
-    @foo.stubs(:to_formula).returns(stub(name: "f", deps: [@qux, @baz]))
-    assert_equal [@qux, @baz, @foo, @bar], Dependency.expand(@f)
-  end
-
-  def test_expand_skips_optionals_by_default
-    deps = [build_dep(:foo, [:optional]), @bar, @baz, @qux]
-    f = stub(deps: deps, build: stub(with?: false), name: "f")
-    assert_equal [@bar, @baz, @qux], Dependency.expand(f)
-  end
-
-  def test_expand_keeps_recommendeds_by_default
-    deps = [build_dep(:foo, [:recommended]), @bar, @baz, @qux]
-    f = stub(deps: deps, build: stub(with?: true), name: "f")
-    assert_equal deps, Dependency.expand(f)
-  end
-
-  def test_merges_repeated_deps_with_differing_options
-    @foo2 = build_dep(:foo, ["option"])
-    @baz2 = build_dep(:baz, ["option"])
-    @deps << @foo2 << @baz2
-    deps = [@foo2, @bar, @baz2, @qux]
-    deps.zip(Dependency.expand(@f)) do |expected, actual|
-      assert_equal expected.tags, actual.tags
-      assert_equal expected, actual
-    end
-  end
-
-  def test_merger_preserves_env_proc
-    env_proc = stub
-    dep = Dependency.new("foo", [], env_proc)
-    dep.stubs(:to_formula).returns(stub(deps: [], name: "foo"))
-    @deps.replace [dep]
-    assert_equal env_proc, Dependency.expand(@f).first.env_proc
-  end
-
-  def test_merged_tags_no_dupes
-    @foo2 = build_dep(:foo, ["option"])
-    @foo3 = build_dep(:foo, ["option"])
-    @deps << @foo2 << @foo3
-
-    assert_equal %w[option], Dependency.expand(@f).first.tags
-  end
-
-  def test_skip_skips_parent_but_yields_children
-    f = stub(
-      name: "f",
-      deps: [
-        build_dep(:foo, [], [@bar, @baz]),
-        build_dep(:foo, [], [@baz]),
-      ]
-    )
-
-    deps = Dependency.expand(f) do |_dependent, dep|
-      Dependency.skip if %w[foo qux].include? dep.name
-    end
-
-    assert_equal [@bar, @baz], deps
-  end
-
-  def test_keep_dep_but_prune_recursive_deps
-    foo = build_dep(:foo, [:build], @bar)
-    baz = build_dep(:baz, [:build])
-    f = stub(name: "f", deps: [foo, baz])
-
-    deps = Dependency.expand(f) do |_dependent, dep|
-      Dependency.keep_but_prune_recursive_deps if dep.build?
-    end
-
-    assert_equal [foo, baz], deps
-  end
-
-  def test_deps_with_collection_argument
-    assert_equal [@foo, @bar, @baz, @qux], @f.deps
-    assert_equal [@bar, @baz], Dependency.expand(@f, [@bar, @baz])
-  end
-
-  def test_cyclic_dependency
-    foo = build_dep(:foo)
-    bar = build_dep(:bar, [], [foo])
-    foo.stubs(:to_formula).returns(stub(deps: [bar], name: "foo"))
-    f = stub(name: "f", deps: [foo, bar])
-    assert_nothing_raised { Dependency.expand(f) }
-  end
-
-  def test_clean_expand_stack
-    foo = build_dep(:foo)
-    foo.stubs(:to_formula).raises(FormulaUnavailableError, "foo")
-    f = stub(name: "f", deps: [foo])
-    assert_raises(FormulaUnavailableError) { Dependency.expand(f) }
-    assert_empty Dependency.instance_variable_get(:@expand_stack)
-  end
-end
diff --git a/Library/Homebrew/test/dependency_test.rb b/Library/Homebrew/test/dependency_test.rb
index 65255995e..404f26d79 100644
--- a/Library/Homebrew/test/dependency_test.rb
+++ b/Library/Homebrew/test/dependency_test.rb
@@ -3,6 +3,7 @@ require "dependency"
 
 class DependableTests < Homebrew::TestCase
   def setup
+    super
     @tags = ["foo", "bar", :build]
     @dep = Struct.new(:tags).new(@tags).extend(Dependable)
   end
@@ -118,6 +119,11 @@ class DependencyTests < Homebrew::TestCase
 end
 
 class TapDependencyTests < Homebrew::TestCase
+  def test_tap
+    dep = TapDependency.new("foo/bar/dog")
+    assert_equal Tap.new("foo", "bar"), dep.tap
+  end
+
   def test_option_names
     dep = TapDependency.new("foo/bar/dog")
     assert_equal %w[dog], dep.option_names
diff --git a/Library/Homebrew/test/deps_spec.rb b/Library/Homebrew/test/deps_spec.rb
new file mode 100644
index 000000000..4c892c93d
--- /dev/null
+++ b/Library/Homebrew/test/deps_spec.rb
@@ -0,0 +1,31 @@
+describe "brew deps", :integration_test do
+  before(:each) do
+    setup_test_formula "foo"
+    setup_test_formula "bar"
+    setup_test_formula "baz", <<-EOS.undent
+      url "https://example.com/baz-1.0"
+      depends_on "bar"
+    EOS
+  end
+
+  it "outputs no dependencies for a Formula that has no dependencies" do
+    expect { brew "deps", "foo" }
+      .to be_a_success
+      .and not_to_output.to_stdout
+      .and not_to_output.to_stderr
+  end
+
+  it "outputs a dependency for a Formula that has one dependency" do
+    expect { brew "deps", "bar" }
+      .to be_a_success
+      .and output("foo\n").to_stdout
+      .and not_to_output.to_stderr
+  end
+
+  it "outputs all of a Formula's dependencies and their dependencies on separate lines" do
+    expect { brew "deps", "baz" }
+      .to be_a_success
+      .and output("bar\nfoo\n").to_stdout
+      .and not_to_output.to_stderr
+  end
+end
diff --git a/Library/Homebrew/test/deps_test.rb b/Library/Homebrew/test/deps_test.rb
deleted file mode 100644
index 01639857c..000000000
--- a/Library/Homebrew/test/deps_test.rb
+++ /dev/null
@@ -1,16 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestDeps < IntegrationCommandTestCase
-  def test_deps
-    setup_test_formula "foo"
-    setup_test_formula "bar"
-    setup_test_formula "baz", <<-EOS.undent
-      url "https://example.com/baz-1.0"
-      depends_on "bar"
-    EOS
-
-    assert_equal "", cmd("deps", "foo")
-    assert_equal "foo", cmd("deps", "bar")
-    assert_equal "bar\nfoo", cmd("deps", "baz")
-  end
-end
diff --git a/Library/Homebrew/test/desc_test.rb b/Library/Homebrew/test/desc_test.rb
deleted file mode 100644
index 2ba498135..000000000
--- a/Library/Homebrew/test/desc_test.rb
+++ /dev/null
@@ -1,17 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestDesc < IntegrationCommandTestCase
-  def test_desc
-    setup_test_formula "testball"
-
-    assert_equal "testball: Some test", cmd("desc", "testball")
-    assert_match "Pick one, and only one", cmd_fail("desc", "--search", "--name")
-    assert_match "You must provide a search term", cmd_fail("desc", "--search")
-
-    desc_cache = HOMEBREW_CACHE/"desc_cache.json"
-    refute_predicate desc_cache, :exist?, "Cached file should not exist"
-
-    cmd("desc", "--description", "testball")
-    assert_predicate desc_cache, :exist?, "Cached file should not exist"
-  end
-end
diff --git a/Library/Homebrew/test/descriptions_spec.rb b/Library/Homebrew/test/descriptions_spec.rb
new file mode 100644
index 000000000..e873c73b4
--- /dev/null
+++ b/Library/Homebrew/test/descriptions_spec.rb
@@ -0,0 +1,42 @@
+require "descriptions"
+
+describe Descriptions do
+  subject { described_class.new(descriptions_hash) }
+  let(:descriptions_hash) { {} }
+
+  it "can print description for a core Formula" do
+    descriptions_hash["homebrew/core/foo"] = "Core foo"
+    expect { subject.print }.to output("foo: Core foo\n").to_stdout
+  end
+
+  it "can print description for an external Formula" do
+    descriptions_hash["somedev/external/foo"] = "External foo"
+    expect { subject.print }.to output("foo: External foo\n").to_stdout
+  end
+
+  it "can print descriptions for duplicate Formulae" do
+    descriptions_hash["homebrew/core/foo"] = "Core foo"
+    descriptions_hash["somedev/external/foo"] = "External foo"
+
+    expect { subject.print }.to output(
+      <<-EOS.undent
+        homebrew/core/foo: Core foo
+        somedev/external/foo: External foo
+      EOS
+    ).to_stdout
+  end
+
+  it "can print descriptions for duplicate core and external Formulae" do
+    descriptions_hash["homebrew/core/foo"] = "Core foo"
+    descriptions_hash["somedev/external/foo"] = "External foo"
+    descriptions_hash["otherdev/external/foo"] = "Other external foo"
+
+    expect { subject.print }.to output(
+      <<-EOS.undent
+        homebrew/core/foo: Core foo
+        otherdev/external/foo: Other external foo
+        somedev/external/foo: External foo
+      EOS
+    ).to_stdout
+  end
+end
diff --git a/Library/Homebrew/test/descriptions_test.rb b/Library/Homebrew/test/descriptions_test.rb
deleted file mode 100644
index de38fdbd1..000000000
--- a/Library/Homebrew/test/descriptions_test.rb
+++ /dev/null
@@ -1,45 +0,0 @@
-require "testing_env"
-require "descriptions"
-
-class DescriptionsTest < Homebrew::TestCase
-  def setup
-    @descriptions_hash = {}
-    @descriptions = Descriptions.new(@descriptions_hash)
-
-    @old_stdout = $stdout
-    $stdout = StringIO.new
-  end
-
-  def teardown
-    $stdout = @old_stdout
-  end
-
-  def test_single_core_formula
-    @descriptions_hash["homebrew/core/foo"] = "Core foo"
-    @descriptions.print
-    assert_equal "foo: Core foo", $stdout.string.chomp
-  end
-
-  def test_single_external_formula
-    @descriptions_hash["somedev/external/foo"] = "External foo"
-    @descriptions.print
-    assert_equal "foo: External foo", $stdout.string.chomp
-  end
-
-  def test_even_dupes
-    @descriptions_hash["homebrew/core/foo"] = "Core foo"
-    @descriptions_hash["somedev/external/foo"] = "External foo"
-    @descriptions.print
-    assert_equal "homebrew/core/foo: Core foo\nsomedev/external/foo: External foo",
-                 $stdout.string.chomp
-  end
-
-  def test_odd_dupes
-    @descriptions_hash["homebrew/core/foo"] = "Core foo"
-    @descriptions_hash["somedev/external/foo"] = "External foo"
-    @descriptions_hash["otherdev/external/foo"] = "Other external foo"
-    @descriptions.print
-    assert_equal "homebrew/core/foo: Core foo\notherdev/external/foo: Other external foo\nsomedev/external/foo: External foo",
-                 $stdout.string.chomp
-  end
-end
diff --git a/Library/Homebrew/test/dev-cmd/bottle_spec.rb b/Library/Homebrew/test/dev-cmd/bottle_spec.rb
new file mode 100644
index 000000000..468ef2e90
--- /dev/null
+++ b/Library/Homebrew/test/dev-cmd/bottle_spec.rb
@@ -0,0 +1,30 @@
+describe "brew bottle", :integration_test do
+  it "builds a bottle for the given Formula" do
+    begin
+      shutup do
+        expect { brew "install", "--build-bottle", testball }
+          .to be_a_success
+      end
+
+      expect { brew "bottle", "--no-rebuild", testball }
+        .to output(/Formula not from core or any taps/).to_stderr
+        .and not_to_output.to_stdout
+        .and be_a_failure
+
+      setup_test_formula "testball"
+
+      # `brew bottle` should not fail with dead symlink
+      # https://github.com/Homebrew/legacy-homebrew/issues/49007
+      (HOMEBREW_CELLAR/"testball/0.1").cd do
+        FileUtils.ln_s "not-exist", "symlink"
+      end
+
+      expect { brew "bottle", "--no-rebuild", "testball" }
+        .to output(/testball-0\.1.*\.bottle\.tar\.gz/).to_stdout
+        .and not_to_output.to_stderr
+        .and be_a_success
+    ensure
+      FileUtils.rm_f Dir.glob("testball-0.1*.bottle.tar.gz")
+    end
+  end
+end
diff --git a/Library/Homebrew/test/dev-cmd/create_spec.rb b/Library/Homebrew/test/dev-cmd/create_spec.rb
new file mode 100644
index 000000000..b7f96ec7f
--- /dev/null
+++ b/Library/Homebrew/test/dev-cmd/create_spec.rb
@@ -0,0 +1,13 @@
+describe "brew create", :integration_test do
+  let(:url) { "file://#{TEST_FIXTURE_DIR}/tarballs/testball-0.1.tbz" }
+  let(:formula_file) { CoreTap.new.formula_dir/"testball.rb" }
+
+  it "creates a new Formula file for a given URL" do
+    shutup do
+      brew "create", url, "HOMEBREW_EDITOR" => "/bin/cat"
+    end
+
+    expect(formula_file).to exist
+    expect(formula_file.read).to match(%Q(sha256 "#{TESTBALL_SHA256}"))
+  end
+end
diff --git a/Library/Homebrew/test/dev-cmd/edit_spec.rb b/Library/Homebrew/test/dev-cmd/edit_spec.rb
new file mode 100644
index 000000000..5cedb0524
--- /dev/null
+++ b/Library/Homebrew/test/dev-cmd/edit_spec.rb
@@ -0,0 +1,16 @@
+describe "brew edit", :integration_test do
+  it "opens a given Formula in an editor" do
+    HOMEBREW_REPOSITORY.cd do
+      shutup do
+        system "git", "init"
+      end
+    end
+
+    setup_test_formula "testball"
+
+    expect { brew "edit", "testball", "HOMEBREW_EDITOR" => "/bin/cat" }
+      .to output(/# something here/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/dev-cmd/formula_spec.rb b/Library/Homebrew/test/dev-cmd/formula_spec.rb
new file mode 100644
index 000000000..cc5b3e9e8
--- /dev/null
+++ b/Library/Homebrew/test/dev-cmd/formula_spec.rb
@@ -0,0 +1,10 @@
+describe "brew formula", :integration_test do
+  it "prints a given Formula's path" do
+    formula_file = setup_test_formula "testball"
+
+    expect { brew "formula", "testball" }
+      .to output("#{formula_file}\n").to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/dev-cmd/pull_spec.rb b/Library/Homebrew/test/dev-cmd/pull_spec.rb
new file mode 100644
index 000000000..3c0108df2
--- /dev/null
+++ b/Library/Homebrew/test/dev-cmd/pull_spec.rb
@@ -0,0 +1,60 @@
+describe "brew pull", :integration_test do
+  it "fails when no argument is given" do
+    expect { brew "pull" }
+      .to output(/This command requires at least one argument/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+  end
+
+  it "fetches a patch from a GitHub commit or pull request and applies it" do
+    skip "Requires network connection." if ENV["HOMEBREW_NO_GITHUB_API"]
+
+    CoreTap.instance.path.cd do
+      shutup do
+        system "git", "init"
+        system "git", "checkout", "-b", "new-branch"
+      end
+    end
+
+    expect { brew "pull", "https://bot.brew.sh/job/Homebrew\%20Testing/1028/" }
+      .to output(/Testing URLs require `\-\-bottle`!/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+
+    expect { brew "pull", "1" }
+      .to output(/Fetching patch/).to_stdout
+      .and output(/Current branch is new\-branch/).to_stderr
+      .and be_a_failure
+
+    expect { brew "pull", "--bump", "8" }
+      .to output(/Fetching patch/).to_stdout
+      .and output(/No changed formulae found to bump/).to_stderr
+      .and be_a_failure
+
+    expect { brew "pull", "--bump", "https://api.github.com/repos/Homebrew/homebrew-core/pulls/122" }
+      .to output(/Fetching patch/).to_stdout
+      .and output(/Can only bump one changed formula/).to_stderr
+      .and be_a_failure
+
+    expect { brew "pull", "https://github.com/Homebrew/homebrew-core/pull/1" }
+      .to output(/Fetching patch/).to_stdout
+      .and output(/Patch failed to apply/).to_stderr
+      .and be_a_failure
+  end
+
+  describe "--rebase" do
+    it "fails" do
+      expect { brew "pull", "--rebase" }
+        .to output(/You meant `git pull --rebase`./).to_stderr
+        .and not_to_output.to_stdout
+        .and be_a_failure
+    end
+  end
+
+  it "fails when given 0" do
+    expect { brew "pull", "0" }
+      .to output(/Not a GitHub pull request or commit/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+  end
+end
diff --git a/Library/Homebrew/test/dev-cmd/tap_spec.rb b/Library/Homebrew/test/dev-cmd/tap_spec.rb
new file mode 100644
index 000000000..a24c67aae
--- /dev/null
+++ b/Library/Homebrew/test/dev-cmd/tap_spec.rb
@@ -0,0 +1,75 @@
+describe "brew tap", :integration_test do
+  it "taps a given Tap" do
+    path = Tap::TAP_DIRECTORY/"homebrew/homebrew-foo"
+    path.mkpath
+    path.cd do
+      shutup do
+        system "git", "init"
+        system "git", "remote", "add", "origin", "https://github.com/Homebrew/homebrew-foo"
+        FileUtils.touch "readme"
+        system "git", "add", "--all"
+        system "git", "commit", "-m", "init"
+      end
+    end
+
+    expect { brew "tap" }
+      .to output(%r{homebrew/foo}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "tap", "--list-official" }
+      .to output(%r{homebrew/science}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "tap-info" }
+      .to output(/2 taps/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "tap-info", "homebrew/foo" }
+      .to output(%r{https://github\.com/Homebrew/homebrew-foo}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "tap-info", "--json=v1", "--installed" }
+      .to output(%r{https://github\.com/Homebrew/homebrew-foo}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "tap-pin", "homebrew/foo" }
+      .to output(%r{Pinned homebrew/foo}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "tap", "--list-pinned" }
+      .to output(%r{homebrew/foo}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "tap-unpin", "homebrew/foo" }
+      .to output(%r{Unpinned homebrew/foo}).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "tap", "homebrew/bar", path/".git" }
+      .to output(/Tapped/).to_stdout
+      .and output(/Cloning/).to_stderr
+      .and be_a_success
+
+    expect { brew "untap", "homebrew/bar" }
+      .to output(/Untapped/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "tap", "homebrew/bar", path/".git", "-q", "--full" }
+      .to be_a_success
+      .and not_to_output.to_stdout
+      .and not_to_output.to_stderr
+
+    expect { brew "untap", "homebrew/bar" }
+      .to output(/Untapped/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/dev-cmd/test_spec.rb b/Library/Homebrew/test/dev-cmd/test_spec.rb
new file mode 100644
index 000000000..b73d042e4
--- /dev/null
+++ b/Library/Homebrew/test/dev-cmd/test_spec.rb
@@ -0,0 +1,56 @@
+describe "brew test", :integration_test do
+  it "fails when no argument is given" do
+    expect { brew "test" }
+      .to output(/This command requires a formula argument/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+  end
+
+  it "fails when a Formula is not installed" do
+    expect { brew "test", testball }
+      .to output(/Testing requires the latest version of testball/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+  end
+
+  it "fails when a Formula has no test" do
+    shutup do
+      expect { brew "install", testball }.to be_a_success
+    end
+
+    expect { brew "test", testball }
+      .to output(/testball defines no test/).to_stderr
+      .and not_to_output.to_stdout
+      .and be_a_failure
+  end
+
+  it "tests a given Formula" do
+    setup_test_formula "testball", <<-EOS.undent
+      head "https://github.com/example/testball2.git"
+
+      devel do
+        url "file://#{TEST_FIXTURE_DIR}/tarballs/testball-0.1.tbz"
+        sha256 "#{TESTBALL_SHA256}"
+      end
+
+      keg_only "just because"
+
+      test do
+      end
+    EOS
+
+    shutup do
+      expect { brew "install", "testball" }.to be_a_success
+    end
+
+    expect { brew "test", "--HEAD", "testball" }
+      .to output(/Testing testball/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+
+    expect { brew "test", "--devel", "testball" }
+      .to output(/Testing testball/).to_stdout
+      .and not_to_output.to_stderr
+      .and be_a_success
+  end
+end
diff --git a/Library/Homebrew/test/diagnostic_spec.rb b/Library/Homebrew/test/diagnostic_spec.rb
new file mode 100644
index 000000000..e749a3b0f
--- /dev/null
+++ b/Library/Homebrew/test/diagnostic_spec.rb
@@ -0,0 +1,188 @@
+require "diagnostic"
+
+describe Homebrew::Diagnostic::Checks do
+  specify "#inject_file_list" do
+    expect(subject.inject_file_list([], "foo:\n")).to eq("foo:\n")
+    expect(subject.inject_file_list(%w[/a /b], "foo:\n")).to eq("foo:\n  /a\n  /b\n")
+  end
+
+  specify "#check_path_for_trailing_slashes" do
+    ENV["PATH"] += File::PATH_SEPARATOR + "/foo/bar/"
+    expect(subject.check_path_for_trailing_slashes)
+      .to match("Some directories in your path end in a slash")
+  end
+
+  specify "#check_for_anaconda" do
+    Dir.mktmpdir do |path|
+      anaconda = "#{path}/anaconda"
+      python = "#{path}/python"
+      FileUtils.touch anaconda
+      File.open(python, "w") do |file|
+        file.write("#! #{`which bash`}\necho -n '#{python}'\n")
+      end
+      FileUtils.chmod 0755, anaconda
+      FileUtils.chmod 0755, python
+
+      ENV["PATH"] = path + File::PATH_SEPARATOR + ENV["PATH"]
+
+      expect(subject.check_for_anaconda).to match("Anaconda")
+    end
+  end
+
+  specify "#check_access_homebrew_repository" do
+    begin
+      mode = HOMEBREW_REPOSITORY.stat.mode & 0777
+      HOMEBREW_REPOSITORY.chmod 0555
+
+      expect(subject.check_access_homebrew_repository)
+        .to match("#{HOMEBREW_REPOSITORY} is not writable.")
+    ensure
+      HOMEBREW_REPOSITORY.chmod mode
+    end
+  end
+
+  specify "#check_access_logs" do
+    begin
+      mode = HOMEBREW_LOGS.stat.mode & 0777
+      HOMEBREW_LOGS.chmod 0555
+
+      expect(subject.check_access_logs)
+        .to match("#{HOMEBREW_LOGS} isn't writable.")
+    ensure
+      HOMEBREW_LOGS.chmod mode
+    end
+  end
+
+  specify "#check_access_cache" do
+    begin
+      mode = HOMEBREW_CACHE.stat.mode & 0777
+      HOMEBREW_CACHE.chmod 0555
+      expect(subject.check_access_cache)
+        .to match("#{HOMEBREW_CACHE} isn't writable.")
+    ensure
+      HOMEBREW_CACHE.chmod mode
+    end
+  end
+
+  specify "#check_access_cellar" do
+    begin
+      mode = HOMEBREW_CELLAR.stat.mode & 0777
+      HOMEBREW_CELLAR.chmod 0555
+
+      expect(subject.check_access_cellar)
+        .to match("#{HOMEBREW_CELLAR} isn't writable.")
+    ensure
+      HOMEBREW_CELLAR.chmod mode
+    end
+  end
+
+  specify "#check_homebrew_prefix" do
+    ENV.delete("JENKINS_HOME")
+    # the integration tests are run in a special prefix
+    expect(subject.check_homebrew_prefix)
+      .to match("Your Homebrew's prefix is not /usr/local.")
+  end
+
+  specify "#check_user_path_1" do
+    bin = HOMEBREW_PREFIX/"bin"
+    sep = File::PATH_SEPARATOR
+    # ensure /usr/bin is before HOMEBREW_PREFIX/bin in the PATH
+    ENV["PATH"] = "/usr/bin#{sep}#{bin}#{sep}" +
+                  ENV["PATH"].gsub(%r{(?:^|#{sep})(?:/usr/bin|#{bin})}, "")
+
+    # ensure there's at least one file with the same name in both /usr/bin/ and
+    # HOMEBREW_PREFIX/bin/
+    (bin/File.basename(Dir["/usr/bin/*"].first)).mkpath
+
+    expect(subject.check_user_path_1)
+      .to match("/usr/bin occurs before #{HOMEBREW_PREFIX}/bin")
+  end
+
+  specify "#check_user_path_2" do
+    ENV["PATH"] = ENV["PATH"].gsub \
+      %r{(?:^|#{File::PATH_SEPARATOR})#{HOMEBREW_PREFIX}/bin}, ""
+
+    expect(subject.check_user_path_1).to be nil
+    expect(subject.check_user_path_2)
+      .to match("Homebrew's bin was not found in your PATH.")
+  end
+
+  specify "#check_user_path_3" do
+    begin
+      sbin = HOMEBREW_PREFIX/"sbin"
+      ENV["PATH"] = "#{HOMEBREW_PREFIX}/bin#{File::PATH_SEPARATOR}" +
+                    ENV["PATH"].gsub(/(?:^|#{Regexp.escape(File::PATH_SEPARATOR)})#{Regexp.escape(sbin)}/, "")
+      (sbin/"something").mkpath
+
+      expect(subject.check_user_path_1).to be nil
+      expect(subject.check_user_path_2).to be nil
+      expect(subject.check_user_path_3)
+        .to match("Homebrew's sbin was not found in your PATH")
+    ensure
+      sbin.rmtree
+    end
+  end
+
+  specify "#check_user_curlrc" do
+    Dir.mktmpdir do |path|
+      FileUtils.touch "#{path}/.curlrc"
+      ENV["CURL_HOME"] = path
+
+      expect(subject.check_user_curlrc).to match("You have a curlrc file")
+    end
+  end
+
+  specify "#check_for_config_scripts" do
+    Dir.mktmpdir do |path|
+      file = "#{path}/foo-config"
+      FileUtils.touch file
+      FileUtils.chmod 0755, file
+      ENV["PATH"] = "#{path}#{File::PATH_SEPARATOR}#{ENV["PATH"]}"
+
+      expect(subject.check_for_config_scripts)
+        .to match('"config" scripts exist')
+    end
+  end
+
+  specify "#check_dyld_vars" do
+    ENV["DYLD_INSERT_LIBRARIES"] = "foo"
+    expect(subject.check_dyld_vars).to match("Setting DYLD_INSERT_LIBRARIES")
+  end
+
+  specify "#check_for_symlinked_cellar" do
+    begin
+      HOMEBREW_CELLAR.rmtree
+
+      Dir.mktmpdir do |path|
+        FileUtils.ln_s path, HOMEBREW_CELLAR
+
+        expect(subject.check_for_symlinked_cellar).to match(path)
+      end
+    ensure
+      HOMEBREW_CELLAR.unlink
+      HOMEBREW_CELLAR.mkpath
+    end
+  end
+
+  specify "#check_tmpdir" do
+    ENV["TMPDIR"] = "/i/don/t/exis/t"
+    expect(subject.check_tmpdir).to match("doesn't exist")
+  end
+
+  specify "#check_for_external_cmd_name_conflict" do
+    Dir.mktmpdir do |path1|
+      Dir.mktmpdir do |path2|
+        [path1, path2].each do |path|
+          cmd = "#{path}/brew-foo"
+          FileUtils.touch cmd
+          FileUtils.chmod 0755, cmd
+        end
+
+        ENV["PATH"] = [path1, path2, ENV["PATH"]].join File::PATH_SEPARATOR
+
+        expect(subject.check_for_external_cmd_name_conflict)
+          .to match("brew-foo")
+      end
+    end
+  end
+end
diff --git a/Library/Homebrew/test/diagnostic_test.rb b/Library/Homebrew/test/diagnostic_test.rb
deleted file mode 100644
index c9bb524b0..000000000
--- a/Library/Homebrew/test/diagnostic_test.rb
+++ /dev/null
@@ -1,198 +0,0 @@
-require "testing_env"
-require "fileutils"
-require "pathname"
-require "diagnostic"
-
-class DiagnosticChecksTest < Homebrew::TestCase
-  def setup
-    @env = ENV.to_hash
-    @checks = Homebrew::Diagnostic::Checks.new
-  end
-
-  def teardown
-    ENV.replace(@env)
-  end
-
-  def test_inject_file_list
-    assert_equal "foo:\n",
-      @checks.inject_file_list([], "foo:\n")
-    assert_equal "foo:\n  /a\n  /b\n",
-      @checks.inject_file_list(%w[/a /b], "foo:\n")
-  end
-
-  def test_check_path_for_trailing_slashes
-    ENV["PATH"] += File::PATH_SEPARATOR + "/foo/bar/"
-    assert_match "Some directories in your path end in a slash",
-      @checks.check_path_for_trailing_slashes
-  end
-
-  def test_check_for_anaconda
-    mktmpdir do |path|
-      anaconda = "#{path}/anaconda"
-      python = "#{path}/python"
-      FileUtils.touch anaconda
-      File.open(python, "w") do |file|
-        file.write("#! #{`which bash`}\necho -n '#{python}'\n")
-      end
-      FileUtils.chmod 0755, anaconda
-      FileUtils.chmod 0755, python
-
-      ENV["PATH"] = path + File::PATH_SEPARATOR + ENV["PATH"]
-
-      assert_match "Anaconda",
-        @checks.check_for_anaconda
-    end
-  end
-
-  def test_check_access_homebrew_repository
-    mod = HOMEBREW_REPOSITORY.stat.mode & 0777
-    HOMEBREW_REPOSITORY.chmod 0555
-
-    assert_match "#{HOMEBREW_REPOSITORY} is not writable.",
-      @checks.check_access_homebrew_repository
-  ensure
-    HOMEBREW_REPOSITORY.chmod mod
-  end
-
-  def test_check_access_logs
-    mod = HOMEBREW_LOGS.stat.mode & 0777
-    HOMEBREW_LOGS.chmod 0555
-
-    assert_match "#{HOMEBREW_LOGS} isn't writable.",
-      @checks.check_access_logs
-  ensure
-    HOMEBREW_LOGS.chmod mod
-  end
-
-  def test_check_access_cache
-    mod = HOMEBREW_CACHE.stat.mode & 0777
-    HOMEBREW_CACHE.chmod 0555
-    assert_match "#{HOMEBREW_CACHE} isn't writable.",
-      @checks.check_access_cache
-  ensure
-    HOMEBREW_CACHE.chmod mod
-  end
-
-  def test_check_access_cellar
-    mod = HOMEBREW_CELLAR.stat.mode & 0777
-    HOMEBREW_CELLAR.chmod 0555
-
-    assert_match "#{HOMEBREW_CELLAR} isn't writable.",
-      @checks.check_access_cellar
-  ensure
-    HOMEBREW_CELLAR.chmod mod
-  end
-
-  def test_check_homebrew_prefix
-    ENV.delete("JENKINS_HOME")
-    # the integration tests are run in a special prefix
-    assert_match "Your Homebrew's prefix is not /usr/local.",
-      @checks.check_homebrew_prefix
-  end
-
-  def test_check_user_path_usr_bin_before_homebrew
-    bin = HOMEBREW_PREFIX/"bin"
-    sep = File::PATH_SEPARATOR
-    # ensure /usr/bin is before HOMEBREW_PREFIX/bin in the PATH
-    ENV["PATH"] = "/usr/bin#{sep}#{bin}#{sep}" +
-                  ENV["PATH"].gsub(%r{(?:^|#{sep})(?:/usr/bin|#{bin})}, "")
-
-    # ensure there's at least one file with the same name in both /usr/bin/ and
-    # HOMEBREW_PREFIX/bin/
-    (bin/File.basename(Dir["/usr/bin/*"].first)).mkpath
-
-    assert_match "/usr/bin occurs before #{HOMEBREW_PREFIX}/bin",
-      @checks.check_user_path_1
-  ensure
-    bin.rmtree
-  end
-
-  def test_check_user_path_bin
-    ENV["PATH"] = ENV["PATH"].gsub \
-      %r{(?:^|#{File::PATH_SEPARATOR})#{HOMEBREW_PREFIX}/bin}, ""
-
-    assert_nil @checks.check_user_path_1
-    assert_match "Homebrew's bin was not found in your PATH.",
-      @checks.check_user_path_2
-  end
-
-  def test_check_user_path_sbin
-    sbin = HOMEBREW_PREFIX/"sbin"
-    ENV["PATH"] = "#{HOMEBREW_PREFIX}/bin#{File::PATH_SEPARATOR}" +
-                  ENV["PATH"].gsub(/(?:^|#{Regexp.escape(File::PATH_SEPARATOR)})#{Regexp.escape(sbin)}/, "")
-    (sbin/"something").mkpath
-
-    assert_nil @checks.check_user_path_1
-    assert_nil @checks.check_user_path_2
-    assert_match "Homebrew's sbin was not found in your PATH",
-      @checks.check_user_path_3
-  ensure
-    sbin.rmtree
-  end
-
-  def test_check_user_curlrc
-    mktmpdir do |path|
-      FileUtils.touch "#{path}/.curlrc"
-      ENV["CURL_HOME"] = path
-
-      assert_match "You have a curlrc file",
-        @checks.check_user_curlrc
-    end
-  end
-
-  def test_check_for_config_scripts
-    mktmpdir do |path|
-      file = "#{path}/foo-config"
-      FileUtils.touch file
-      FileUtils.chmod 0755, file
-      ENV["PATH"] = "#{path}#{File::PATH_SEPARATOR}#{ENV["PATH"]}"
-
-      assert_match '"config" scripts exist',
-        @checks.check_for_config_scripts
-    end
-  end
-
-  def test_check_dyld_vars
-    ENV["DYLD_INSERT_LIBRARIES"] = "foo"
-    assert_match "Setting DYLD_INSERT_LIBRARIES",
-      @checks.check_dyld_vars
-  end
-
-  def test_check_for_symlinked_cellar
-    HOMEBREW_CELLAR.rmtree
-
-    mktmpdir do |path|
-      FileUtils.ln_s path, HOMEBREW_CELLAR
-
-      assert_match path,
-        @checks.check_for_symlinked_cellar
-    end
-
-  ensure
-    HOMEBREW_CELLAR.unlink
-    HOMEBREW_CELLAR.mkpath
-  end
-
-  def test_check_tmpdir
-    ENV["TMPDIR"] = "/i/don/t/exis/t"
-    assert_match "doesn't exist",
-      @checks.check_tmpdir
-  end
-
-  def test_check_for_external_cmd_name_conflict
-    mktmpdir do |path1|
-      mktmpdir do |path2|
-        [path1, path2].each do |path|
-          cmd = "#{path}/brew-foo"
-          FileUtils.touch cmd
-          FileUtils.chmod 0755, cmd
-        end
-
-        ENV["PATH"] = [path1, path2, ENV["PATH"]].join File::PATH_SEPARATOR
-
-        assert_match "brew-foo",
-          @checks.check_for_external_cmd_name_conflict
-      end
-    end
-  end
-end
diff --git a/Library/Homebrew/test/doctor_test.rb b/Library/Homebrew/test/doctor_test.rb
deleted file mode 100644
index d2dc871f4..000000000
--- a/Library/Homebrew/test/doctor_test.rb
+++ /dev/null
@@ -1,8 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestDoctor < IntegrationCommandTestCase
-  def test_doctor
-    assert_match "This is an integration test",
-                 cmd_fail("doctor", "check_integration_test")
-  end
-end
diff --git a/Library/Homebrew/test/download_strategies_spec.rb b/Library/Homebrew/test/download_strategies_spec.rb
new file mode 100644
index 000000000..f466b97f4
--- /dev/null
+++ b/Library/Homebrew/test/download_strategies_spec.rb
@@ -0,0 +1,232 @@
+require "download_strategy"
+
+describe AbstractDownloadStrategy do
+  subject { described_class.new(name, resource) }
+  let(:name) { "foo" }
+  let(:url) { "http://example.com/foo.tar.gz" }
+  let(:resource) { double(Resource, url: url, mirrors: [], specs: {}, version: nil) }
+  let(:args) { %w[foo bar baz] }
+
+  describe "#expand_safe_system_args" do
+    it "works with an explicit quiet flag" do
+      args << { quiet_flag: "--flag" }
+      expanded_args = subject.expand_safe_system_args(args)
+      expect(expanded_args).to eq(%w[foo bar baz --flag])
+    end
+
+    it "adds an implicit quiet flag" do
+      expanded_args = subject.expand_safe_system_args(args)
+      expect(expanded_args).to eq(%w[foo bar -q baz])
+    end
+
+    it "does not mutate the arguments" do
+      result = subject.expand_safe_system_args(args)
+      expect(args).to eq(%w[foo bar baz])
+      expect(result).not_to be args
+    end
+  end
+
+  specify "#source_modified_time" do
+    FileUtils.mktemp "mtime" do
+      FileUtils.touch "foo", mtime: Time.now - 10
+      FileUtils.touch "bar", mtime: Time.now - 100
+      FileUtils.ln_s "not-exist", "baz"
+      expect(subject.source_modified_time).to eq(File.mtime("foo"))
+    end
+  end
+end
+
+describe VCSDownloadStrategy do
+  let(:url) { "http://example.com/bar" }
+  let(:resource) { double(Resource, url: url, mirrors: [], specs: {}, version: nil) }
+
+  describe "#cached_location" do
+    it "returns the path of the cached resource" do
+      allow_any_instance_of(described_class).to receive(:cache_tag).and_return("foo")
+      downloader = described_class.new("baz", resource)
+      expect(downloader.cached_location).to eq(HOMEBREW_CACHE/"baz--foo")
+    end
+  end
+end
+
+describe GitHubPrivateRepositoryDownloadStrategy do
+  subject { described_class.new("foo", resource) }
+  let(:url) { "https://github.com/owner/repo/archive/1.1.5.tar.gz" }
+  let(:resource) { double(Resource, url: url, mirrors: [], specs: {}, version: nil) }
+
+  before(:each) do
+    ENV["HOMEBREW_GITHUB_API_TOKEN"] = "token"
+    allow(GitHub).to receive(:repository).and_return({})
+  end
+
+  it "sets the @github_token instance variable" do
+    expect(subject.instance_variable_get(:@github_token)).to eq("token")
+  end
+
+  it "parses the URL and sets the corresponding instance variables" do
+    expect(subject.instance_variable_get(:@owner)).to eq("owner")
+    expect(subject.instance_variable_get(:@repo)).to eq("repo")
+    expect(subject.instance_variable_get(:@filepath)).to eq("archive/1.1.5.tar.gz")
+  end
+
+  its(:download_url) { is_expected.to eq("https://token@github.com/owner/repo/archive/1.1.5.tar.gz") }
+end
+
+describe GitHubPrivateRepositoryReleaseDownloadStrategy do
+  subject { described_class.new("foo", resource) }
+  let(:url) { "https://github.com/owner/repo/releases/download/tag/foo_v0.1.0_darwin_amd64.tar.gz" }
+  let(:resource) { double(Resource, url: url, mirrors: [], specs: {}, version: nil) }
+
+  before(:each) do
+    ENV["HOMEBREW_GITHUB_API_TOKEN"] = "token"
+    allow(GitHub).to receive(:repository).and_return({})
+  end
+
+  it "parses the URL and sets the corresponding instance variables" do
+    expect(subject.instance_variable_get(:@owner)).to eq("owner")
+    expect(subject.instance_variable_get(:@repo)).to eq("repo")
+    expect(subject.instance_variable_get(:@tag)).to eq("tag")
+    expect(subject.instance_variable_get(:@filename)).to eq("foo_v0.1.0_darwin_amd64.tar.gz")
+  end
+
+  describe "#download_url" do
+    it "returns the download URL for a given resource" do
+      allow(subject).to receive(:resolve_asset_id).and_return(456)
+      expect(subject.download_url).to eq("https://token@api.github.com/repos/owner/repo/releases/assets/456")
+    end
+  end
+
+  specify "#resolve_asset_id" do
+    release_metadata = {
+      "assets" => [
+        {
+          "id" => 123,
+          "name" => "foo_v0.1.0_linux_amd64.tar.gz",
+        },
+        {
+          "id" => 456,
+          "name" => "foo_v0.1.0_darwin_amd64.tar.gz",
+        },
+      ],
+    }
+    allow(subject).to receive(:fetch_release_metadata).and_return(release_metadata)
+    expect(subject.send(:resolve_asset_id)).to eq(456)
+  end
+
+  describe "#fetch_release_metadata" do
+    it "fetches release metadata from GitHub" do
+      expected_release_url = "https://api.github.com/repos/owner/repo/releases/tags/tag"
+      expect(GitHub).to receive(:open).with(expected_release_url).and_return({})
+      subject.send(:fetch_release_metadata)
+    end
+  end
+end
+
+describe GitHubGitDownloadStrategy do
+  subject { described_class.new(name, resource) }
+  let(:name) { "brew" }
+  let(:url) { "https://github.com/homebrew/brew.git" }
+  let(:resource) { double(Resource, url: url, mirrors: [], specs: {}, version: nil) }
+
+  it "parses the URL and sets the corresponding instance variables" do
+    expect(subject.instance_variable_get(:@user)).to eq("homebrew")
+    expect(subject.instance_variable_get(:@repo)).to eq("brew")
+  end
+end
+
+describe GitDownloadStrategy do
+  subject { described_class.new(name, resource) }
+  let(:name) { "baz" }
+  let(:url) { "https://github.com/homebrew/foo" }
+  let(:resource) { double(Resource, url: url, mirrors: [], specs: {}, version: nil) }
+  let(:cached_location) { subject.cached_location }
+
+  before(:each) do
+    @commit_id = 1
+    FileUtils.mkpath cached_location
+  end
+
+  def git_commit_all
+    shutup do
+      system "git", "add", "--all"
+      system "git", "commit", "-m", "commit number #{@commit_id}"
+      @commit_id += 1
+    end
+  end
+
+  def setup_git_repo
+    shutup do
+      system "git", "init"
+      system "git", "remote", "add", "origin", "https://github.com/Homebrew/homebrew-foo"
+    end
+    FileUtils.touch "README"
+    git_commit_all
+  end
+
+  describe "#source_modified_time" do
+    it "returns the right modification time" do
+      cached_location.cd do
+        setup_git_repo
+      end
+      expect(subject.source_modified_time.to_i).to eq(1_485_115_153)
+    end
+  end
+
+  specify "#last_commit" do
+    cached_location.cd do
+      setup_git_repo
+      FileUtils.touch "LICENSE"
+      git_commit_all
+    end
+    expect(subject.last_commit).to eq("f68266e")
+  end
+
+  describe "#fetch_last_commit" do
+    let(:url) { "file://#{remote_repo}" }
+    let(:version) { Version.create("HEAD") }
+    let(:resource) { double(Resource, url: url, mirrors: [], specs: {}, version: version) }
+    let(:remote_repo) { HOMEBREW_PREFIX/"remote_repo" }
+
+    before(:each) { remote_repo.mkpath }
+
+    after(:each) { FileUtils.rm_rf remote_repo }
+
+    it "fetches the hash of the last commit" do
+      remote_repo.cd do
+        setup_git_repo
+        FileUtils.touch "LICENSE"
+        git_commit_all
+      end
+
+      subject.shutup!
+      expect(subject.fetch_last_commit).to eq("f68266e")
+    end
+  end
+end
+
+describe DownloadStrategyDetector do
+  describe "::detect" do
+    subject { described_class.detect(url) }
+    let(:url) { Object.new }
+
+    context "when given Git URL" do
+      let(:url) { "git://example.com/foo.git" }
+      it { is_expected.to eq(GitDownloadStrategy) }
+    end
+
+    context "when given a GitHub Git URL" do
+      let(:url) { "https://github.com/homebrew/brew.git" }
+      it { is_expected.to eq(GitHubGitDownloadStrategy) }
+    end
+
+    it "defaults to cURL" do
+      expect(subject).to eq(CurlDownloadStrategy)
+    end
+
+    it "raises an error when passed an unrecognized strategy" do
+      expect {
+        described_class.detect("foo", Class.new)
+      }.to raise_error(TypeError)
+    end
+  end
+end
diff --git a/Library/Homebrew/test/download_strategies_test.rb b/Library/Homebrew/test/download_strategies_test.rb
deleted file mode 100644
index 2b64abbf9..000000000
--- a/Library/Homebrew/test/download_strategies_test.rb
+++ /dev/null
@@ -1,262 +0,0 @@
-require "testing_env"
-require "download_strategy"
-
-class ResourceDouble
-  attr_reader :url, :specs, :version, :mirrors
-
-  def initialize(url = "http://example.com/foo.tar.gz", specs = {})
-    @url = url
-    @specs = specs
-    @mirrors = []
-  end
-end
-
-class AbstractDownloadStrategyTests < Homebrew::TestCase
-  include FileUtils
-
-  def setup
-    @name = "foo"
-    @resource = ResourceDouble.new
-    @strategy = AbstractDownloadStrategy.new(@name, @resource)
-    @args = %w[foo bar baz]
-  end
-
-  def test_expand_safe_system_args_with_explicit_quiet_flag
-    @args << { quiet_flag: "--flag" }
-    expanded_args = @strategy.expand_safe_system_args(@args)
-    assert_equal %w[foo bar baz --flag], expanded_args
-  end
-
-  def test_expand_safe_system_args_with_implicit_quiet_flag
-    expanded_args = @strategy.expand_safe_system_args(@args)
-    assert_equal %w[foo bar -q baz], expanded_args
-  end
-
-  def test_expand_safe_system_args_does_not_mutate_argument
-    result = @strategy.expand_safe_system_args(@args)
-    assert_equal %w[foo bar baz], @args
-    refute_same @args, result
-  end
-
-  def test_source_modified_time
-    mktemp "mtime" do
-      touch "foo", mtime: Time.now - 10
-      touch "bar", mtime: Time.now - 100
-      ln_s "not-exist", "baz"
-      assert_equal File.mtime("foo"), @strategy.source_modified_time
-    end
-  end
-end
-
-class VCSDownloadStrategyTests < Homebrew::TestCase
-  def test_cache_filename
-    resource = ResourceDouble.new("http://example.com/bar")
-    strategy = Class.new(VCSDownloadStrategy) do
-      def cache_tag
-        "foo"
-      end
-    end
-    downloader = strategy.new("baz", resource)
-    assert_equal HOMEBREW_CACHE.join("baz--foo"), downloader.cached_location
-  end
-end
-
-class GitHubPrivateRepositoryDownloadStrategyTests < Homebrew::TestCase
-  def setup
-    resource = ResourceDouble.new("https://github.com/owner/repo/archive/1.1.5.tar.gz")
-    ENV["HOMEBREW_GITHUB_API_TOKEN"] = "token"
-    GitHub.stubs(:repository).returns {}
-    @strategy = GitHubPrivateRepositoryDownloadStrategy.new("foo", resource)
-  end
-
-  def test_set_github_token
-    assert_equal "token", @strategy.instance_variable_get(:@github_token)
-  end
-
-  def test_parse_url_pattern
-    assert_equal "owner", @strategy.instance_variable_get(:@owner)
-    assert_equal "repo", @strategy.instance_variable_get(:@repo)
-    assert_equal "archive/1.1.5.tar.gz", @strategy.instance_variable_get(:@filepath)
-  end
-
-  def test_download_url
-    expected = "https://token@github.com/owner/repo/archive/1.1.5.tar.gz"
-    assert_equal expected, @strategy.download_url
-  end
-end
-
-class GitHubPrivateRepositoryReleaseDownloadStrategyTests < Homebrew::TestCase
-  def setup
-    resource = ResourceDouble.new("https://github.com/owner/repo/releases/download/tag/foo_v0.1.0_darwin_amd64.tar.gz")
-    ENV["HOMEBREW_GITHUB_API_TOKEN"] = "token"
-    GitHub.stubs(:repository).returns {}
-    @strategy = GitHubPrivateRepositoryReleaseDownloadStrategy.new("foo", resource)
-  end
-
-  def test_parse_url_pattern
-    assert_equal "owner", @strategy.instance_variable_get(:@owner)
-    assert_equal "repo", @strategy.instance_variable_get(:@repo)
-    assert_equal "tag", @strategy.instance_variable_get(:@tag)
-    assert_equal "foo_v0.1.0_darwin_amd64.tar.gz", @strategy.instance_variable_get(:@filename)
-  end
-
-  def test_download_url
-    @strategy.stubs(:resolve_asset_id).returns(456)
-    expected = "https://token@api.github.com/repos/owner/repo/releases/assets/456"
-    assert_equal expected, @strategy.download_url
-  end
-
-  def test_resolve_asset_id
-    release_metadata = {
-      "assets" => [
-        {
-          "id" => 123,
-          "name" => "foo_v0.1.0_linux_amd64.tar.gz",
-        },
-        {
-          "id" => 456,
-          "name" => "foo_v0.1.0_darwin_amd64.tar.gz",
-        },
-      ],
-    }
-    @strategy.stubs(:fetch_release_metadata).returns(release_metadata)
-    assert_equal 456, @strategy.send(:resolve_asset_id)
-  end
-
-  def test_fetch_release_metadata
-    expected_release_url = "https://api.github.com/repos/owner/repo/releases/tags/tag"
-    github_mock = MiniTest::Mock.new
-    github_mock.expect :call, {}, [expected_release_url]
-    GitHub.stub :open, github_mock do
-      @strategy.send(:fetch_release_metadata)
-    end
-    github_mock.verify
-  end
-end
-
-class GitDownloadStrategyTests < Homebrew::TestCase
-  include FileUtils
-
-  def setup
-    resource = ResourceDouble.new("https://github.com/homebrew/foo")
-    @commit_id = 1
-    @strategy = GitDownloadStrategy.new("baz", resource)
-    @cached_location = @strategy.cached_location
-    mkpath @cached_location
-  end
-
-  def teardown
-    rmtree @cached_location
-  end
-
-  def git_commit_all
-    shutup do
-      system "git", "add", "--all"
-      system "git", "commit", "-m", "commit number #{@commit_id}"
-      @commit_id += 1
-    end
-  end
-
-  def using_git_env
-    initial_env = ENV.to_hash
-    %w[AUTHOR COMMITTER].each do |role|
-      ENV["GIT_#{role}_NAME"] = "brew tests"
-      ENV["GIT_#{role}_EMAIL"] = "brew-tests@localhost"
-      ENV["GIT_#{role}_DATE"] = "Thu May 21 00:04:11 2009 +0100"
-    end
-    yield
-  ensure
-    ENV.replace(initial_env)
-  end
-
-  def setup_git_repo
-    using_git_env do
-      @cached_location.cd do
-        shutup do
-          system "git", "init"
-          system "git", "remote", "add", "origin", "https://github.com/Homebrew/homebrew-foo"
-        end
-        touch "README"
-        git_commit_all
-      end
-    end
-  end
-
-  def test_github_git_download_strategy_user_repo
-    resource = ResourceDouble.new("https://github.com/homebrew/brew.git")
-    strategy = GitHubGitDownloadStrategy.new("brew", resource)
-
-    assert_equal strategy.instance_variable_get(:@user), "homebrew"
-    assert_equal strategy.instance_variable_get(:@repo), "brew"
-  end
-
-  def test_source_modified_time
-    setup_git_repo
-    assert_equal 1_242_860_651, @strategy.source_modified_time.to_i
-  end
-
-  def test_last_commit
-    setup_git_repo
-    using_git_env do
-      @cached_location.cd do
-        touch "LICENSE"
-        git_commit_all
-      end
-    end
-    assert_equal "c50c79b", @strategy.last_commit
-  end
-
-  def test_fetch_last_commit
-    remote_repo = HOMEBREW_PREFIX.join("remote_repo")
-    remote_repo.mkdir
-
-    resource = ResourceDouble.new("file://#{remote_repo}")
-    resource.instance_variable_set(:@version, Version.create("HEAD"))
-    @strategy = GitDownloadStrategy.new("baz", resource)
-
-    using_git_env do
-      remote_repo.cd do
-        shutup do
-          system "git", "init"
-          system "git", "remote", "add", "origin", "https://github.com/Homebrew/homebrew-foo"
-        end
-        touch "README"
-        git_commit_all
-        touch "LICENSE"
-        git_commit_all
-      end
-    end
-
-    @strategy.shutup!
-    assert_equal "c50c79b", @strategy.fetch_last_commit
-  ensure
-    remote_repo.rmtree if remote_repo.directory?
-  end
-end
-
-class DownloadStrategyDetectorTests < Homebrew::TestCase
-  def setup
-    @d = DownloadStrategyDetector.new
-  end
-
-  def test_detect_git_download_startegy
-    @d = DownloadStrategyDetector.detect("git://example.com/foo.git")
-    assert_equal GitDownloadStrategy, @d
-  end
-
-  def test_detect_github_git_download_strategy
-    @d = DownloadStrategyDetector.detect("https://github.com/homebrew/brew.git")
-    assert_equal GitHubGitDownloadStrategy, @d
-  end
-
-  def test_default_to_curl_strategy
-    @d = DownloadStrategyDetector.detect(Object.new)
-    assert_equal CurlDownloadStrategy, @d
-  end
-
-  def test_raises_when_passed_unrecognized_strategy
-    assert_raises(TypeError) do
-      DownloadStrategyDetector.detect("foo", Class.new)
-    end
-  end
-end
diff --git a/Library/Homebrew/test/edit_test.rb b/Library/Homebrew/test/edit_test.rb
deleted file mode 100644
index 9b6ded651..000000000
--- a/Library/Homebrew/test/edit_test.rb
+++ /dev/null
@@ -1,11 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestEdit < IntegrationCommandTestCase
-  def test_edit
-    (HOMEBREW_REPOSITORY/".git").mkpath
-    setup_test_formula "testball"
-
-    assert_match "# something here",
-                 cmd("edit", "testball", "HOMEBREW_EDITOR" => "/bin/cat")
-  end
-end
diff --git a/Library/Homebrew/test/emoji_spec.rb b/Library/Homebrew/test/emoji_spec.rb
new file mode 100644
index 000000000..35d077ebe
--- /dev/null
+++ b/Library/Homebrew/test/emoji_spec.rb
@@ -0,0 +1,16 @@
+require "emoji"
+
+describe Emoji do
+  describe "#install_badge" do
+    subject { described_class.install_badge }
+
+    it "returns 🍺 by default" do
+      expect(subject).to eq "🍺"
+    end
+
+    it "returns the contents of HOMEBREW_INSTALL_BADGE if set" do
+      ENV["HOMEBREW_INSTALL_BADGE"] = "foo"
+      expect(subject).to eq "foo"
+    end
+  end
+end
diff --git a/Library/Homebrew/test/exceptions_spec.rb b/Library/Homebrew/test/exceptions_spec.rb
new file mode 100644
index 000000000..33547ea32
--- /dev/null
+++ b/Library/Homebrew/test/exceptions_spec.rb
@@ -0,0 +1,188 @@
+require "exceptions"
+
+describe MultipleVersionsInstalledError do
+  subject { described_class.new("foo") }
+  its(:to_s) { is_expected.to eq("foo has multiple installed versions") }
+end
+
+describe NoSuchKegError do
+  subject { described_class.new("foo") }
+  its(:to_s) { is_expected.to eq("No such keg: #{HOMEBREW_CELLAR}/foo") }
+end
+
+describe FormulaValidationError do
+  subject { described_class.new("foo", "sha257", "magic") }
+  its(:to_s) {
+    is_expected.to eq(%q(invalid attribute for formula 'foo': sha257 ("magic")))
+  }
+end
+
+describe FormulaUnavailableError do
+  subject { described_class.new("foo") }
+
+  describe "#dependent_s" do
+    it "returns nil if there is no dependent" do
+      expect(subject.dependent_s).to be nil
+    end
+
+    it "returns nil if it depended on by itself" do
+      subject.dependent = "foo"
+      expect(subject.dependent_s).to be nil
+    end
+
+    it "returns a string if there is a dependent" do
+      subject.dependent = "foobar"
+      expect(subject.dependent_s).to eq("(dependency of foobar)")
+    end
+  end
+
+  context "without a dependent" do
+    its(:to_s) { is_expected.to eq('No available formula with the name "foo" ') }
+  end
+
+  context "with a dependent" do
+    before(:each) do
+      subject.dependent = "foobar"
+    end
+
+    its(:to_s) {
+      is_expected.to eq('No available formula with the name "foo" (dependency of foobar)')
+    }
+  end
+end
+
+describe TapFormulaUnavailableError do
+  subject { described_class.new(tap, "foo") }
+  let(:tap) { double(Tap, user: "u", repo: "r", to_s: "u/r", installed?: false) }
+  its(:to_s) { is_expected.to match(%r{Please tap it and then try again: brew tap u/r}) }
+end
+
+describe FormulaClassUnavailableError do
+  subject { described_class.new("foo", "foo.rb", "Foo", list) }
+  let(:mod) do
+    Module.new do
+      class Bar < Requirement; end
+      class Baz < Formula; end
+    end
+  end
+
+  context "no classes" do
+    let(:list) { [] }
+    its(:to_s) {
+      is_expected.to match(/Expected to find class Foo, but found no classes\./)
+    }
+  end
+
+  context "class not derived from Formula" do
+    let(:list) { [mod.const_get(:Bar)] }
+    its(:to_s) {
+      is_expected.to match(/Expected to find class Foo, but only found: Bar \(not derived from Formula!\)\./)
+    }
+  end
+
+  context "class derived from Formula" do
+    let(:list) { [mod.const_get(:Baz)] }
+    its(:to_s) { is_expected.to match(/Expected to find class Foo, but only found: Baz\./) }
+  end
+end
+
+describe FormulaUnreadableError do
+  subject { described_class.new("foo", formula_error) }
+  let(:formula_error) { LoadError.new("bar") }
+  its(:to_s) { is_expected.to eq("foo: bar") }
+end
+
+describe TapUnavailableError do
+  subject { described_class.new("foo") }
+  its(:to_s) { is_expected.to eq("No available tap foo.\n") }
+end
+
+describe TapAlreadyTappedError do
+  subject { described_class.new("foo") }
+  its(:to_s) { is_expected.to eq("Tap foo already tapped.\n") }
+end
+
+describe TapPinStatusError do
+  context "pinned" do
+    subject { described_class.new("foo", true) }
+    its(:to_s) { is_expected.to eq("foo is already pinned.") }
+  end
+
+  context "unpinned" do
+    subject { described_class.new("foo", false) }
+    its(:to_s) { is_expected.to eq("foo is already unpinned.") }
+  end
+end
+
+describe BuildError do
+  subject { described_class.new(formula, "badprg", %w[arg1 arg2], {}) }
+  let(:formula) { double(Formula, name: "foo") }
+  its(:to_s) { is_expected.to eq("Failed executing: badprg arg1 arg2") }
+end
+
+describe OperationInProgressError do
+  subject { described_class.new("foo") }
+  its(:to_s) { is_expected.to match(/Operation already in progress for foo/) }
+end
+
+describe FormulaInstallationAlreadyAttemptedError do
+  subject { described_class.new(formula) }
+  let(:formula) { double(Formula, full_name: "foo/bar") }
+  its(:to_s) { is_expected.to eq("Formula installation already attempted: foo/bar") }
+end
+
+describe FormulaConflictError do
+  subject { described_class.new(formula, [conflict]) }
+  let(:formula) { double(Formula, full_name: "foo/qux") }
+  let(:conflict) { double(name: "bar", reason: "I decided to") }
+  its(:to_s) { is_expected.to match(/Please `brew unlink bar` before continuing\./) }
+end
+
+describe CompilerSelectionError do
+  subject { described_class.new(formula) }
+  let(:formula) { double(Formula, full_name: "foo") }
+  its(:to_s) { is_expected.to match(/foo cannot be built with any available compilers\./) }
+end
+
+describe CurlDownloadStrategyError do
+  context "file does not exist" do
+    subject { described_class.new("file:///tmp/foo") }
+    its(:to_s) { is_expected.to eq("File does not exist: /tmp/foo") }
+  end
+
+  context "download failed" do
+    subject { described_class.new("http://brew.sh") }
+    its(:to_s) { is_expected.to eq("Download failed: http://brew.sh") }
+  end
+end
+
+describe ErrorDuringExecution do
+  subject { described_class.new("badprg", %w[arg1 arg2]) }
+  its(:to_s) { is_expected.to eq("Failure while executing: badprg arg1 arg2") }
+end
+
+describe ChecksumMismatchError do
+  subject { described_class.new("/file.tar.gz", hash1, hash2) }
+  let(:hash1) { double(hash_type: "sha256", to_s: "deadbeef") }
+  let(:hash2) { double(hash_type: "sha256", to_s: "deadcafe") }
+  its(:to_s) { is_expected.to match(/SHA256 mismatch/) }
+end
+
+describe ResourceMissingError do
+  subject { described_class.new(formula, resource) }
+  let(:formula) { double(Formula, full_name: "bar") }
+  let(:resource) { double(inspect: "<resource foo>") }
+  its(:to_s) { is_expected.to eq("bar does not define resource <resource foo>") }
+end
+
+describe DuplicateResourceError do
+  subject { described_class.new(resource) }
+  let(:resource) { double(inspect: "<resource foo>") }
+  its(:to_s) { is_expected.to eq("Resource <resource foo> is defined more than once") }
+end
+
+describe BottleVersionMismatchError do
+  subject { described_class.new("/foo.bottle.tar.gz", "1.0", formula, "1.1") }
+  let(:formula) { double(Formula, full_name: "foo") }
+  its(:to_s) { is_expected.to match(/Bottle version mismatch/) }
+end
diff --git a/Library/Homebrew/test/exceptions_test.rb b/Library/Homebrew/test/exceptions_test.rb
deleted file mode 100644
index 689531c6e..000000000
--- a/Library/Homebrew/test/exceptions_test.rb
+++ /dev/null
@@ -1,142 +0,0 @@
-require "testing_env"
-require "exceptions"
-
-class ExceptionsTest < Homebrew::TestCase
-  def test_multiple_versions_installed_error
-    assert_equal "foo has multiple installed versions",
-      MultipleVersionsInstalledError.new("foo").to_s
-  end
-
-  def test_no_such_keg_error
-    assert_equal "No such keg: #{HOMEBREW_CELLAR}/foo",
-      NoSuchKegError.new("foo").to_s
-  end
-
-  def test_formula_validation_error
-    assert_equal %q(invalid attribute for formula 'foo': sha257 ("magic")),
-      FormulaValidationError.new("foo", "sha257", "magic").to_s
-  end
-
-  def test_formula_unavailable_error
-    e = FormulaUnavailableError.new "foo"
-    assert_nil e.dependent_s
-
-    e.dependent = "foo"
-    assert_nil e.dependent_s
-
-    e.dependent = "foobar"
-    assert_equal "(dependency of foobar)", e.dependent_s
-
-    assert_equal "No available formula with the name \"foo\" (dependency of foobar)",
-      e.to_s
-  end
-
-  def test_tap_formula_unavailable_error
-    t = stub(user: "u", repo: "r", to_s: "u/r", installed?: false)
-    assert_match "Please tap it and then try again: brew tap u/r",
-      TapFormulaUnavailableError.new(t, "foo").to_s
-  end
-
-  def test_formula_class_unavailable_error
-    mod = Module.new
-    mod.module_eval <<-EOS.undent
-      class Bar < Requirement; end
-      class Baz < Formula; end
-    EOS
-
-    assert_match "Expected to find class Foo, but found no classes.",
-      FormulaClassUnavailableError.new("foo", "foo.rb", "Foo", []).to_s
-
-    list = [mod.const_get(:Bar)]
-    assert_match "Expected to find class Foo, but only found: Bar (not derived from Formula!).",
-      FormulaClassUnavailableError.new("foo", "foo.rb", "Foo", list).to_s
-
-    list = [mod.const_get(:Baz)]
-    assert_match "Expected to find class Foo, but only found: Baz.",
-      FormulaClassUnavailableError.new("foo", "foo.rb", "Foo", list).to_s
-  end
-
-  def test_tap_unavailable_error
-    assert_equal "No available tap foo.\n", TapUnavailableError.new("foo").to_s
-  end
-
-  def test_tap_already_tapped_error
-    assert_equal "Tap foo already tapped.\n",
-      TapAlreadyTappedError.new("foo").to_s
-  end
-
-  def test_pin_status_error
-    assert_equal "foo is already pinned.",
-      TapPinStatusError.new("foo", true).to_s
-    assert_equal "foo is already unpinned.",
-      TapPinStatusError.new("foo", false).to_s
-  end
-
-  def test_build_error
-    f = stub(name: "foo")
-    assert_equal "Failed executing: badprg arg1 arg2",
-      BuildError.new(f, "badprg", %w[arg1 arg2], {}).to_s
-  end
-
-  def test_operation_in_progress_error
-    assert_match "Operation already in progress for bar",
-      OperationInProgressError.new("bar").to_s
-  end
-
-  def test_formula_installation_already_attempted_error
-    f = stub(full_name: "foo/bar")
-    assert_equal "Formula installation already attempted: foo/bar",
-      FormulaInstallationAlreadyAttemptedError.new(f).to_s
-  end
-
-  def test_formula_conflict_error
-    f = stub(full_name: "foo/qux")
-    c = stub(name: "bar", reason: "I decided to")
-    assert_match "Please `brew unlink bar` before continuing.",
-      FormulaConflictError.new(f, [c]).to_s
-  end
-
-  def test_compiler_selection_error
-    f = stub(full_name: "foo")
-    assert_match "foo cannot be built with any available compilers.",
-      CompilerSelectionError.new(f).to_s
-  end
-
-  def test_curl_download_strategy_error
-    assert_equal "File does not exist: /tmp/foo",
-      CurlDownloadStrategyError.new("file:///tmp/foo").to_s
-    assert_equal "Download failed: http://brew.sh",
-      CurlDownloadStrategyError.new("http://brew.sh").to_s
-  end
-
-  def test_error_during_execution
-    assert_equal "Failure while executing: badprg arg1 arg2",
-      ErrorDuringExecution.new("badprg", %w[arg1 arg2]).to_s
-  end
-
-  def test_checksum_mismatch_error
-    h1 = stub(hash_type: "sha256", to_s: "deadbeef")
-    h2 = stub(hash_type: "sha256", to_s: "deadcafe")
-    assert_match "SHA256 mismatch",
-      ChecksumMismatchError.new("/file.tar.gz", h1, h2).to_s
-  end
-
-  def test_resource_missing_error
-    f = stub(full_name: "bar")
-    r = stub(inspect: "<resource foo>")
-    assert_match "bar does not define resource <resource foo>",
-      ResourceMissingError.new(f, r).to_s
-  end
-
-  def test_duplicate_resource_error
-    r = stub(inspect: "<resource foo>")
-    assert_equal "Resource <resource foo> is defined more than once",
-      DuplicateResourceError.new(r).to_s
-  end
-
-  def test_bottle_version_mismatch_error
-    f = stub(full_name: "foo")
-    assert_match "Bottle version mismatch",
-      BottleVersionMismatchError.new("/foo.bottle.tar.gz", "1.0", f, "1.1").to_s
-  end
-end
diff --git a/Library/Homebrew/test/fetch_test.rb b/Library/Homebrew/test/fetch_test.rb
deleted file mode 100644
index e08e545e3..000000000
--- a/Library/Homebrew/test/fetch_test.rb
+++ /dev/null
@@ -1,11 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestFetch < IntegrationCommandTestCase
-  def test_fetch
-    setup_test_formula "testball"
-
-    cmd("fetch", "testball")
-    assert((HOMEBREW_CACHE/"testball-0.1.tbz").exist?,
-      "The tarball should have been cached")
-  end
-end
diff --git a/Library/Homebrew/test/formula_installer_test.rb b/Library/Homebrew/test/formula_installer_test.rb
index 652548bd7..c99b2de74 100644
--- a/Library/Homebrew/test/formula_installer_test.rb
+++ b/Library/Homebrew/test/formula_installer_test.rb
@@ -84,13 +84,10 @@ class InstallTests < Homebrew::TestCase
 
     cc_arg = "--cc=clang"
     ARGV << cc_arg
-    begin
-      temporary_install(TestballBottle.new) do |f|
-        tab = Tab.for_formula(f)
-        assert_equal "clang", tab.compiler
-      end
-    ensure
-      ARGV.delete_if { |x| x == cc_arg }
+
+    temporary_install(TestballBottle.new) do |f|
+      tab = Tab.for_formula(f)
+      assert_equal "clang", tab.compiler
     end
   end
 end
@@ -128,11 +125,7 @@ class FormulaInstallerTests < Homebrew::TestCase
     fi = FormulaInstaller.new(dependent)
     assert_raises(CannotInstallFormulaError) { fi.check_install_sanity }
   ensure
-    dependency.unpin
     dependency_keg.unlink
-    dependency_keg.uninstall
-    dependency.clear_cache
-    dep_path.unlink
     Formulary::FORMULAE.delete(dep_path)
   end
 end
diff --git a/Library/Homebrew/test/formula_lock_spec.rb b/Library/Homebrew/test/formula_lock_spec.rb
new file mode 100644
index 000000000..9b5ece813
--- /dev/null
+++ b/Library/Homebrew/test/formula_lock_spec.rb
@@ -0,0 +1,34 @@
+require "formula_lock"
+
+describe FormulaLock do
+  subject { described_class.new("foo") }
+
+  describe "#lock" do
+    it "does not raise an error when already locked" do
+      subject.lock
+
+      expect { subject.lock }.not_to raise_error
+    end
+
+    it "raises an error if a lock already exists" do
+      subject.lock
+
+      expect {
+        described_class.new("foo").lock
+      }.to raise_error(OperationInProgressError)
+    end
+  end
+
+  describe "#unlock" do
+    it "does not raise an error when already unlocked" do
+      expect { subject.unlock }.not_to raise_error
+    end
+
+    it "unlocks a locked Formula" do
+      subject.lock
+      subject.unlock
+
+      expect { described_class.new("foo").lock }.not_to raise_error
+    end
+  end
+end
diff --git a/Library/Homebrew/test/formula_lock_test.rb b/Library/Homebrew/test/formula_lock_test.rb
deleted file mode 100644
index 80ee9dd25..000000000
--- a/Library/Homebrew/test/formula_lock_test.rb
+++ /dev/null
@@ -1,22 +0,0 @@
-require "testing_env"
-require "formula_lock"
-
-class FormulaLockTests < Homebrew::TestCase
-  def setup
-    @lock = FormulaLock.new("foo")
-    @lock.lock
-  end
-
-  def teardown
-    @lock.unlock
-    HOMEBREW_LOCK_DIR.children.each(&:unlink)
-  end
-
-  def test_locking_file_with_existing_lock_raises_error
-    assert_raises(OperationInProgressError) { FormulaLock.new("foo").lock }
-  end
-
-  def test_locking_existing_lock_suceeds
-    assert_nothing_raised { @lock.lock }
-  end
-end
diff --git a/Library/Homebrew/test/formula_pin_spec.rb b/Library/Homebrew/test/formula_pin_spec.rb
new file mode 100644
index 000000000..909bfbc2b
--- /dev/null
+++ b/Library/Homebrew/test/formula_pin_spec.rb
@@ -0,0 +1,41 @@
+require "formula_pin"
+
+describe FormulaPin do
+  subject { described_class.new(formula) }
+  let(:name) { "double" }
+  let(:formula) { double(Formula, name: name, rack: HOMEBREW_CELLAR/name) }
+
+  before(:each) do
+    formula.rack.mkpath
+
+    allow(formula).to receive(:installed_prefixes) do
+      formula.rack.directory? ? formula.rack.subdirs : []
+    end
+
+    allow(formula).to receive(:installed_kegs) do
+      formula.installed_prefixes.map { |prefix| Keg.new(prefix) }
+    end
+  end
+
+  it "is not pinnable by default" do
+    expect(subject).not_to be_pinnable
+  end
+
+  it "is pinnable if the Keg exists" do
+    (formula.rack/"0.1").mkpath
+    expect(subject).to be_pinnable
+  end
+
+  specify "#pin and #unpin" do
+    (formula.rack/"0.1").mkpath
+
+    subject.pin
+    expect(subject).to be_pinned
+    expect(HOMEBREW_PINNED_KEGS/name).to be_a_directory
+    expect(HOMEBREW_PINNED_KEGS.children.count).to eq(1)
+
+    subject.unpin
+    expect(subject).not_to be_pinned
+    expect(HOMEBREW_PINNED_KEGS).not_to be_a_directory
+  end
+end
diff --git a/Library/Homebrew/test/formula_pin_test.rb b/Library/Homebrew/test/formula_pin_test.rb
deleted file mode 100644
index 297d7703e..000000000
--- a/Library/Homebrew/test/formula_pin_test.rb
+++ /dev/null
@@ -1,54 +0,0 @@
-require "testing_env"
-require "formula_pin"
-
-class FormulaPinTests < Homebrew::TestCase
-  class FormulaDouble
-    def name
-      "double"
-    end
-
-    def rack
-      HOMEBREW_CELLAR/name
-    end
-
-    def installed_prefixes
-      rack.directory? ? rack.subdirs : []
-    end
-
-    def installed_kegs
-      installed_prefixes.map { |d| Keg.new d }
-    end
-  end
-
-  def setup
-    @f   = FormulaDouble.new
-    @pin = FormulaPin.new(@f)
-    @f.rack.mkpath
-  end
-
-  def test_not_pinnable
-    refute_predicate @pin, :pinnable?
-  end
-
-  def test_pinnable_if_kegs_exist
-    (@f.rack/"0.1").mkpath
-    assert_predicate @pin, :pinnable?
-  end
-
-  def test_unpin
-    (@f.rack/"0.1").mkpath
-    @pin.pin
-
-    assert_predicate @pin, :pinned?
-    assert_equal 1, HOMEBREW_PINNED_KEGS.children.length
-
-    @pin.unpin
-
-    refute_predicate @pin, :pinned?
-    refute_predicate HOMEBREW_PINNED_KEGS, :directory?
-  end
-
-  def teardown
-    @f.rack.rmtree
-  end
-end
diff --git a/Library/Homebrew/test/formula_spec.rb b/Library/Homebrew/test/formula_spec.rb
new file mode 100644
index 000000000..1e064912f
--- /dev/null
+++ b/Library/Homebrew/test/formula_spec.rb
@@ -0,0 +1,1295 @@
+require "test/support/fixtures/testball"
+require "formula"
+
+RSpec::Matchers.alias_matcher :follow_installed_alias, :be_follow_installed_alias
+RSpec::Matchers.alias_matcher :have_any_version_installed, :be_any_version_installed
+RSpec::Matchers.alias_matcher :need_migration, :be_migration_needed
+
+RSpec::Matchers.alias_matcher :have_changed_installed_alias_target, :be_installed_alias_target_changed
+RSpec::Matchers.alias_matcher :supersede_an_installed_formula, :be_supersedes_an_installed_formula
+RSpec::Matchers.alias_matcher :have_changed_alias, :be_alias_changed
+
+RSpec::Matchers.alias_matcher :have_option_defined, :be_option_defined
+RSpec::Matchers.alias_matcher :have_post_install_defined, :be_post_install_defined
+RSpec::Matchers.alias_matcher :have_test_defined, :be_test_defined
+RSpec::Matchers.alias_matcher :pour_bottle, :be_pour_bottle
+
+describe Formula do
+  describe "::new" do
+    let(:klass) do
+      Class.new(described_class) do
+        url "http://example.com/foo-1.0.tar.gz"
+      end
+    end
+
+    let(:name) { "formula_name" }
+    let(:path) { Formulary.core_path(name) }
+    let(:spec) { :stable }
+    let(:alias_name) { "baz@1" }
+    let(:alias_path) { CoreTap.instance.alias_dir/alias_name }
+    let(:f) { klass.new(name, path, spec) }
+    let(:f_alias) { klass.new(name, path, spec, alias_path: alias_path) }
+
+    specify "formula instantiation" do
+      expect(f.name).to eq(name)
+      expect(f.specified_name).to eq(name)
+      expect(f.full_name).to eq(name)
+      expect(f.full_specified_name).to eq(name)
+      expect(f.path).to eq(path)
+      expect(f.alias_path).to be nil
+      expect(f.alias_name).to be nil
+      expect(f.full_alias_name).to be nil
+      expect { klass.new }.to raise_error(ArgumentError)
+    end
+
+    specify "formula instantiation with alias" do
+      expect(f_alias.name).to eq(name)
+      expect(f_alias.full_name).to eq(name)
+      expect(f_alias.path).to eq(path)
+      expect(f_alias.alias_path).to eq(alias_path)
+      expect(f_alias.alias_name).to eq(alias_name)
+      expect(f_alias.specified_name).to eq(alias_name)
+      expect(f_alias.full_alias_name).to eq(alias_name)
+      expect(f_alias.full_specified_name).to eq(alias_name)
+      expect { klass.new }.to raise_error(ArgumentError)
+    end
+
+    context "in a Tap" do
+      let(:tap) { Tap.new("foo", "bar") }
+      let(:path) { (tap.path/"Formula/#{name}.rb") }
+      let(:full_name) { "#{tap.user}/#{tap.repo}/#{name}" }
+      let(:full_alias_name) { "#{tap.user}/#{tap.repo}/#{alias_name}" }
+
+      specify "formula instantiation" do
+        expect(f.name).to eq(name)
+        expect(f.specified_name).to eq(name)
+        expect(f.full_name).to eq(full_name)
+        expect(f.full_specified_name).to eq(full_name)
+        expect(f.path).to eq(path)
+        expect(f.alias_path).to be nil
+        expect(f.alias_name).to be nil
+        expect(f.full_alias_name).to be nil
+        expect { klass.new }.to raise_error(ArgumentError)
+      end
+
+      specify "formula instantiation with alias" do
+        expect(f_alias.name).to eq(name)
+        expect(f_alias.full_name).to eq(full_name)
+        expect(f_alias.path).to eq(path)
+        expect(f_alias.alias_path).to eq(alias_path)
+        expect(f_alias.alias_name).to eq(alias_name)
+        expect(f_alias.specified_name).to eq(alias_name)
+        expect(f_alias.full_alias_name).to eq(full_alias_name)
+        expect(f_alias.full_specified_name).to eq(full_alias_name)
+        expect { klass.new }.to raise_error(ArgumentError)
+      end
+    end
+  end
+
+  describe "#follow_installed_alias?" do
+    let(:f) do
+      formula do
+        url "foo-1.0"
+      end
+    end
+
+    it "returns true by default" do
+      expect(f).to follow_installed_alias
+    end
+
+    it "can be set to true" do
+      f.follow_installed_alias = true
+      expect(f).to follow_installed_alias
+    end
+
+    it "can be set to false" do
+      f.follow_installed_alias = false
+      expect(f).not_to follow_installed_alias
+    end
+  end
+
+  example "installed alias with core" do
+    f = formula do
+      url "foo-1.0"
+    end
+
+    build_values_with_no_installed_alias = [
+      nil,
+      BuildOptions.new({}, {}),
+      Tab.new(source: { "path" => f.path.to_s }),
+    ]
+    build_values_with_no_installed_alias.each do |build|
+      f.build = build
+      expect(f.installed_alias_path).to be nil
+      expect(f.installed_alias_name).to be nil
+      expect(f.full_installed_alias_name).to be nil
+      expect(f.installed_specified_name).to eq(f.name)
+      expect(f.full_installed_specified_name).to eq(f.name)
+    end
+
+    alias_name = "bar"
+    alias_path = "#{CoreTap.instance.alias_dir}/#{alias_name}"
+
+    f.build = Tab.new(source: { "path" => alias_path })
+
+    expect(f.installed_alias_path).to eq(alias_path)
+    expect(f.installed_alias_name).to eq(alias_name)
+    expect(f.full_installed_alias_name).to eq(alias_name)
+    expect(f.installed_specified_name).to eq(alias_name)
+    expect(f.full_installed_specified_name).to eq(alias_name)
+  end
+
+  example "installed alias with tap" do
+    tap = Tap.new("user", "repo")
+    name = "foo"
+    path = "#{tap.path}/Formula/#{name}.rb"
+    f = formula name, path: path do
+      url "foo-1.0"
+    end
+
+    build_values_with_no_installed_alias = [nil, BuildOptions.new({}, {}), Tab.new(source: { "path" => f.path })]
+    build_values_with_no_installed_alias.each do |build|
+      f.build = build
+      expect(f.installed_alias_path).to be nil
+      expect(f.installed_alias_name).to be nil
+      expect(f.full_installed_alias_name).to be nil
+      expect(f.installed_specified_name).to eq(f.name)
+      expect(f.full_installed_specified_name).to eq(f.full_name)
+    end
+
+    alias_name = "bar"
+    full_alias_name = "#{tap.user}/#{tap.repo}/#{alias_name}"
+    alias_path = "#{tap.alias_dir}/#{alias_name}"
+
+    f.build = Tab.new(source: { "path" => alias_path })
+
+    expect(f.installed_alias_path).to eq(alias_path)
+    expect(f.installed_alias_name).to eq(alias_name)
+    expect(f.full_installed_alias_name).to eq(full_alias_name)
+    expect(f.installed_specified_name).to eq(alias_name)
+    expect(f.full_installed_specified_name).to eq(full_alias_name)
+  end
+
+  specify "#prefix" do
+    f = Testball.new
+    expect(f.prefix).to eq(HOMEBREW_CELLAR/f.name/"0.1")
+    expect(f.prefix).to be_kind_of(Pathname)
+  end
+
+  example "revised prefix" do
+    f = Class.new(Testball) { revision(1) }.new
+    expect(f.prefix).to eq(HOMEBREW_CELLAR/f.name/"0.1_1")
+  end
+
+  specify "#any_version_installed?" do
+    f = formula do
+      url "foo"
+      version "1.0"
+    end
+
+    expect(f).not_to have_any_version_installed
+
+    prefix = HOMEBREW_CELLAR/f.name/"0.1"
+    prefix.mkpath
+    FileUtils.touch prefix/Tab::FILENAME
+
+    expect(f).to have_any_version_installed
+  end
+
+  specify "#migration_needed" do
+    f = Testball.new("newname")
+    f.instance_variable_set(:@oldname, "oldname")
+    f.instance_variable_set(:@tap, CoreTap.instance)
+
+    oldname_prefix = (HOMEBREW_CELLAR/"oldname/2.20")
+    newname_prefix = (HOMEBREW_CELLAR/"newname/2.10")
+
+    oldname_prefix.mkpath
+    oldname_tab = Tab.empty
+    oldname_tab.tabfile = oldname_prefix/Tab::FILENAME
+    oldname_tab.write
+
+    expect(f).not_to need_migration
+
+    oldname_tab.tabfile.unlink
+    oldname_tab.source["tap"] = "homebrew/core"
+    oldname_tab.write
+
+    expect(f).to need_migration
+
+    newname_prefix.mkpath
+
+    expect(f).not_to need_migration
+  end
+
+  describe "#installed?" do
+    let(:f) { Testball.new }
+
+    it "returns false if the #installed_prefix is not a directory" do
+      allow(f).to receive(:installed_prefix).and_return(double(directory?: false))
+      expect(f).not_to be_installed
+    end
+
+    it "returns false if the #installed_prefix does not have children" do
+      allow(f).to receive(:installed_prefix).and_return(double(directory?: true, children: []))
+      expect(f).not_to be_installed
+    end
+
+    it "returns true if the #installed_prefix has children" do
+      allow(f).to receive(:installed_prefix).and_return(double(directory?: true, children: [double]))
+      expect(f).to be_installed
+    end
+  end
+
+  describe "#installed prefix" do
+    let(:f) do
+      formula do
+        url "foo"
+        version "1.9"
+
+        head "foo"
+
+        devel do
+          url "foo"
+          version "2.1-devel"
+        end
+      end
+    end
+
+    let(:stable_prefix) { HOMEBREW_CELLAR/f.name/f.version }
+    let(:devel_prefix) { HOMEBREW_CELLAR/f.name/f.devel.version }
+    let(:head_prefix) { HOMEBREW_CELLAR/f.name/f.head.version }
+
+    it "is the same as #prefix by default" do
+      expect(f.installed_prefix).to eq(f.prefix)
+    end
+
+    it "returns the stable prefix if it is installed" do
+      stable_prefix.mkpath
+      expect(f.installed_prefix).to eq(stable_prefix)
+    end
+
+    it "returns the devel prefix if it is installed" do
+      devel_prefix.mkpath
+      expect(f.installed_prefix).to eq(devel_prefix)
+    end
+
+    it "returns the head prefix if it is installed" do
+      head_prefix.mkpath
+      expect(f.installed_prefix).to eq(head_prefix)
+    end
+
+    it "returns the stable prefix if head is outdated" do
+      head_prefix.mkpath
+
+      tab = Tab.empty
+      tab.tabfile = head_prefix/Tab::FILENAME
+      tab.source["versions"] = { "stable" => "1.0" }
+      tab.write
+
+      expect(f.installed_prefix).to eq(stable_prefix)
+    end
+
+    it "returns the stable prefix if head and devel are outdated" do
+      head_prefix.mkpath
+
+      tab = Tab.empty
+      tab.tabfile = head_prefix/Tab::FILENAME
+      tab.source["versions"] = { "stable" => "1.9", "devel" => "2.0" }
+      tab.write
+
+      expect(f.installed_prefix).to eq(stable_prefix)
+    end
+
+    it "returns the devel prefix if the active specification is :devel" do
+      f.active_spec = :devel
+      expect(f.installed_prefix).to eq(devel_prefix)
+    end
+
+    it "returns the head prefix if the active specification is :head" do
+      f.active_spec = :head
+      expect(f.installed_prefix).to eq(head_prefix)
+    end
+  end
+
+  describe "#latest_head_prefix" do
+    let(:f) { Testball.new }
+
+    it "returns the latest head prefix" do
+      stamps_with_revisions = [
+        [111111, 1],
+        [222222, 0],
+        [222222, 1],
+        [222222, 2],
+      ]
+
+      stamps_with_revisions.each do |stamp, revision|
+        version = "HEAD-#{stamp}"
+        version << "_#{revision}" unless revision.zero?
+
+        prefix = f.rack/version
+        prefix.mkpath
+
+        tab = Tab.empty
+        tab.tabfile = prefix/Tab::FILENAME
+        tab.source_modified_time = stamp
+        tab.write
+      end
+
+      prefix = HOMEBREW_CELLAR/f.name/"HEAD-222222_2"
+
+      expect(f.latest_head_prefix).to eq(prefix)
+    end
+  end
+
+  specify "equality" do
+    x = Testball.new
+    y = Testball.new
+
+    expect(x).to eq(y)
+    expect(x).to eql(y)
+    expect(x.hash).to eq(y.hash)
+  end
+
+  specify "inequality" do
+    x = Testball.new("foo")
+    y = Testball.new("bar")
+
+    expect(x).not_to eq(y)
+    expect(x).not_to eql(y)
+    expect(x.hash).not_to eq(y.hash)
+  end
+
+  specify "comparison with non formula objects does not raise" do
+    expect(Object.new).not_to eq(Testball.new)
+  end
+
+  specify "#<=>" do
+    expect(Testball.new <=> Object.new).to be nil
+  end
+
+  describe "#installed_alias_path" do
+    example "alias paths with build options" do
+      alias_path = (CoreTap.instance.alias_dir/"another_name")
+
+      f = formula alias_path: alias_path do
+        url "foo-1.0"
+      end
+      f.build = BuildOptions.new({}, {})
+
+      expect(f.alias_path).to eq(alias_path)
+      expect(f.installed_alias_path).to be nil
+    end
+
+    example "alias paths with tab with non alias source path" do
+      alias_path = (CoreTap.instance.alias_dir/"another_name")
+      source_path = (CoreTap.instance.formula_dir/"another_other_name")
+
+      f = formula alias_path: alias_path do
+        url "foo-1.0"
+      end
+      f.build = Tab.new(source: { "path" => source_path.to_s })
+
+      expect(f.alias_path).to eq(alias_path)
+      expect(f.installed_alias_path).to be nil
+    end
+
+    example "alias paths with tab with alias source path" do
+      alias_path = (CoreTap.instance.alias_dir/"another_name")
+      source_path = (CoreTap.instance.alias_dir/"another_other_name")
+
+      f = formula alias_path: alias_path do
+        url "foo-1.0"
+      end
+      f.build = Tab.new(source: { "path" => source_path.to_s })
+
+      expect(f.alias_path).to eq(alias_path)
+      expect(f.installed_alias_path).to eq(source_path.to_s)
+    end
+  end
+
+  describe "::installed_with_alias_path" do
+    specify "with alias path with nil" do
+      expect(described_class.installed_with_alias_path(nil)).to be_empty
+    end
+
+    specify "with alias path with a path" do
+      alias_path = "#{CoreTap.instance.alias_dir}/alias"
+      different_alias_path = "#{CoreTap.instance.alias_dir}/another_alias"
+
+      formula_with_alias = formula "foo" do
+        url "foo-1.0"
+      end
+      formula_with_alias.build = Tab.empty
+      formula_with_alias.build.source["path"] = alias_path
+
+      formula_without_alias = formula "bar" do
+        url "bar-1.0"
+      end
+      formula_without_alias.build = Tab.empty
+      formula_without_alias.build.source["path"] = formula_without_alias.path.to_s
+
+      formula_with_different_alias = formula "baz" do
+        url "baz-1.0"
+      end
+      formula_with_different_alias.build = Tab.empty
+      formula_with_different_alias.build.source["path"] = different_alias_path
+
+      formulae = [
+        formula_with_alias,
+        formula_without_alias,
+        formula_with_different_alias,
+      ]
+
+      allow(described_class).to receive(:installed).and_return(formulae)
+
+      expect(described_class.installed_with_alias_path(alias_path))
+        .to eq([formula_with_alias])
+    end
+  end
+
+  specify "spec integration" do
+    f = formula do
+      homepage "http://example.com"
+
+      url "http://example.com/test-0.1.tbz"
+      mirror "http://example.org/test-0.1.tbz"
+      sha256 TEST_SHA256
+
+      head "http://example.com/test.git", tag: "foo"
+
+      devel do
+        url "http://example.com/test-0.2.tbz"
+        mirror "http://example.org/test-0.2.tbz"
+        sha256 TEST_SHA256
+      end
+    end
+
+    expect(f.homepage).to eq("http://example.com")
+    expect(f.version).to eq(Version.create("0.1"))
+    expect(f).to be_stable
+    expect(f.stable.version).to eq(Version.create("0.1"))
+    expect(f.devel.version).to eq(Version.create("0.2"))
+    expect(f.head.version).to eq(Version.create("HEAD"))
+  end
+
+  specify "#active_spec=" do
+    f = formula do
+      url "foo"
+      version "1.0"
+      revision 1
+
+      devel do
+        url "foo"
+        version "1.0beta"
+      end
+    end
+
+    expect(f.active_spec_sym).to eq(:stable)
+    expect(f.send(:active_spec)).to eq(f.stable)
+    expect(f.pkg_version.to_s).to eq("1.0_1")
+
+    f.active_spec = :devel
+
+    expect(f.active_spec_sym).to eq(:devel)
+    expect(f.send(:active_spec)).to eq(f.devel)
+    expect(f.pkg_version.to_s).to eq("1.0beta_1")
+    expect { f.active_spec = :head }.to raise_error(FormulaSpecificationError)
+  end
+
+  specify "class specs are always initialized" do
+    f = formula do
+      url "foo-1.0"
+    end
+
+    expect(f.class.stable).to be_kind_of(SoftwareSpec)
+    expect(f.class.devel).to be_kind_of(SoftwareSpec)
+    expect(f.class.head).to be_kind_of(SoftwareSpec)
+  end
+
+  specify "incomplete instance specs are not accessible" do
+    f = formula do
+      url "foo-1.0"
+    end
+
+    expect(f.devel).to be nil
+    expect(f.head).to be nil
+  end
+
+  it "honors attributes declared before specs" do
+    f = formula do
+      url "foo-1.0"
+
+      depends_on "foo"
+
+      devel do
+        url "foo-1.1"
+      end
+    end
+
+    expect(f.class.stable.deps.first.name).to eq("foo")
+    expect(f.class.devel.deps.first.name).to eq("foo")
+    expect(f.class.head.deps.first.name).to eq("foo")
+  end
+
+  describe "#pkg_version" do
+    specify "simple version" do
+      f = formula do
+        url "foo-1.0.bar"
+      end
+
+      expect(f.pkg_version).to eq(PkgVersion.parse("1.0"))
+    end
+
+    specify "version with revision" do
+      f = formula do
+        url "foo-1.0.bar"
+        revision 1
+      end
+
+      expect(f.pkg_version).to eq(PkgVersion.parse("1.0_1"))
+    end
+
+    specify "head uses revisions" do
+      f = formula "test", spec: :head do
+        url "foo-1.0.bar"
+        revision 1
+
+        head "foo"
+      end
+
+      expect(f.pkg_version).to eq(PkgVersion.parse("HEAD_1"))
+    end
+  end
+
+  specify "#update_head_version" do
+    f = formula do
+      head "foo", using: :git
+    end
+
+    cached_location = f.head.downloader.cached_location
+    cached_location.mkpath
+    cached_location.cd do
+      FileUtils.touch "LICENSE"
+
+      shutup do
+        system("git", "init")
+        system("git", "add", "--all")
+        system("git", "commit", "-m", "Initial commit")
+      end
+    end
+
+    f.update_head_version
+
+    expect(f.head.version).to eq(Version.create("HEAD-5658946"))
+  end
+
+  specify "legacy options" do
+    f = formula do
+      url "foo-1.0"
+
+      def options
+        [
+          ["--foo", "desc"],
+          ["--bar", "desc"],
+        ]
+      end
+
+      option("baz")
+    end
+
+    expect(f).to have_option_defined("foo")
+    expect(f).to have_option_defined("bar")
+    expect(f).to have_option_defined("baz")
+  end
+
+  specify "#desc" do
+    f = formula do
+      desc "a formula"
+
+      url "foo-1.0"
+    end
+
+    expect(f.desc).to eq("a formula")
+  end
+
+  specify "#post_install_defined?" do
+    f1 = formula do
+      url "foo-1.0"
+
+      def post_install
+        # do nothing
+      end
+    end
+
+    f2 = formula do
+      url "foo-1.0"
+    end
+
+    expect(f1).to have_post_install_defined
+    expect(f2).not_to have_post_install_defined
+  end
+
+  specify "#test_defined?" do
+    f1 = formula do
+      url "foo-1.0"
+
+      def test
+        # do nothing
+      end
+    end
+
+    f2 = formula do
+      url "foo-1.0"
+    end
+
+    expect(f1).to have_test_defined
+    expect(f2).not_to have_test_defined
+  end
+
+  specify "test fixtures" do
+    f1 = formula do
+      url "foo-1.0"
+    end
+
+    expect(f1.test_fixtures("foo")).to eq(Pathname.new("#{HOMEBREW_LIBRARY_PATH}/test/support/fixtures/foo"))
+  end
+
+  specify "dependencies" do
+    f1 = formula "f1" do
+      url "f1-1.0"
+    end
+
+    f2 = formula "f2" do
+      url "f2-1.0"
+    end
+
+    f3 = formula "f3" do
+      url "f3-1.0"
+
+      depends_on "f1" => :build
+      depends_on "f2"
+    end
+
+    f4 = formula "f4" do
+      url "f4-1.0"
+
+      depends_on "f1"
+    end
+
+    stub_formula_loader(f1)
+    stub_formula_loader(f2)
+    stub_formula_loader(f3)
+    stub_formula_loader(f4)
+
+    f5 = formula "f5" do
+      url "f5-1.0"
+
+      depends_on "f3" => :build
+      depends_on "f4"
+    end
+
+    expect(f5.deps.map(&:name)).to eq(["f3", "f4"])
+    expect(f5.recursive_dependencies.map(&:name)).to eq(["f1", "f2", "f3", "f4"])
+    expect(f5.runtime_dependencies.map(&:name)).to eq(["f1", "f4"])
+  end
+
+  specify "runtime dependencies with optional deps from tap" do
+    tap_loader = double
+
+    allow(tap_loader).to receive(:get_formula).and_raise(RuntimeError, "tried resolving tap formula")
+    allow(Formulary).to receive(:loader_for).with("foo/bar/f1", from: nil).and_return(tap_loader)
+    stub_formula_loader(formula("f2") { url("f2-1.0") }, "baz/qux/f2")
+
+    f3 = formula "f3" do
+      url "f3-1.0"
+
+      depends_on "foo/bar/f1" => :optional
+      depends_on "baz/qux/f2"
+    end
+
+    expect(f3.runtime_dependencies.map(&:name)).to eq(["baz/qux/f2"])
+
+    stub_formula_loader(formula("f1") { url("f1-1.0") }, "foo/bar/f1")
+    f3.build = BuildOptions.new(Options.create(["--with-f1"]), f3.options)
+
+    expect(f3.runtime_dependencies.map(&:name)).to eq(["foo/bar/f1", "baz/qux/f2"])
+  end
+
+  specify "requirements" do
+    f1 = formula "f1" do
+      url "f1-1"
+
+      depends_on :python
+      depends_on x11: :recommended
+      depends_on xcode: ["1.0", :optional]
+    end
+    stub_formula_loader(f1)
+
+    python = PythonRequirement.new
+    x11 = X11Requirement.new("x11", [:recommended])
+    xcode = XcodeRequirement.new(["1.0", :optional])
+
+    expect(Set.new(f1.recursive_requirements)).to eq(Set[python, x11])
+
+    f1.build = BuildOptions.new(["--with-xcode", "--without-x11"], f1.options)
+
+    expect(Set.new(f1.recursive_requirements)).to eq(Set[python, xcode])
+
+    f1.build = f1.stable.build
+    f2 = formula "f2" do
+      url "f2-1"
+
+      depends_on "f1"
+    end
+
+    expect(Set.new(f2.recursive_requirements)).to eq(Set[python, x11])
+    expect(Set.new(f2.recursive_requirements {})).to eq(Set[python, x11, xcode])
+
+    requirements = f2.recursive_requirements do |_dependent, requirement|
+      Requirement.prune if requirement.is_a?(PythonRequirement)
+    end
+
+    expect(Set.new(requirements)).to eq(Set[x11, xcode])
+  end
+
+  specify "#to_hash" do
+    f1 = formula "foo" do
+      url "foo-1.0"
+
+      bottle do
+        cellar(:any)
+        sha256(TEST_SHA256 => Utils::Bottles.tag)
+      end
+    end
+
+    h = f1.to_hash
+
+    expect(h).to be_a(Hash)
+    expect(h["name"]).to eq("foo")
+    expect(h["full_name"]).to eq("foo")
+    expect(h["versions"]["stable"]).to eq("1.0")
+    expect(h["versions"]["bottle"]).to be_truthy
+  end
+
+  describe "#eligible_kegs_for_cleanup" do
+    it "returns Kegs eligible for cleanup" do
+      f1 = Class.new(Testball) do
+        version("1.0")
+      end.new
+
+      f2 = Class.new(Testball) do
+        version("0.2")
+        version_scheme(1)
+      end.new
+
+      f3 = Class.new(Testball) do
+        version("0.3")
+        version_scheme(1)
+      end.new
+
+      f4 = Class.new(Testball) do
+        version("0.1")
+        version_scheme(2)
+      end.new
+
+      shutup do
+        [f1, f2, f3, f4].each do |f|
+          f.brew { f.install }
+          Tab.create(f, DevelopmentTools.default_compiler, :libcxx).write
+        end
+      end
+
+      expect(f1).to be_installed
+      expect(f2).to be_installed
+      expect(f3).to be_installed
+      expect(f4).to be_installed
+      expect(f3.eligible_kegs_for_cleanup.sort_by(&:version))
+        .to eq([f2, f1].map { |f| Keg.new(f.prefix) })
+    end
+
+    specify "with pinned Keg" do
+      f1 = Class.new(Testball) { version("0.1") }.new
+      f2 = Class.new(Testball) { version("0.2") }.new
+      f3 = Class.new(Testball) { version("0.3") }.new
+
+      shutup do
+        f1.brew { f1.install }
+        f1.pin
+        f2.brew { f2.install }
+        f3.brew { f3.install }
+      end
+
+      expect(f1.prefix).to eq((HOMEBREW_PINNED_KEGS/f1.name).resolved_path)
+      expect(f1).to be_installed
+      expect(f2).to be_installed
+      expect(f3).to be_installed
+      expect(shutup { f3.eligible_kegs_for_cleanup }).to eq([Keg.new(f2.prefix)])
+    end
+
+    specify "with HEAD installed" do
+      f = formula do
+        version("0.1")
+        head("foo")
+      end
+
+      stable_prefix = f.installed_prefix
+      stable_prefix.mkpath
+
+      [["000000_1", 1], ["111111", 2], ["111111_1", 2]].each do |pkg_version_suffix, stamp|
+        prefix = f.prefix("HEAD-#{pkg_version_suffix}")
+        prefix.mkpath
+        tab = Tab.empty
+        tab.tabfile = prefix/Tab::FILENAME
+        tab.source_modified_time = stamp
+        tab.write
+      end
+
+      eligible_kegs = f.installed_kegs - [Keg.new(f.prefix("HEAD-111111_1"))]
+      expect(f.eligible_kegs_for_cleanup).to eq(eligible_kegs)
+    end
+  end
+
+  describe "#pour_bottle?" do
+    it "returns false if set to false" do
+      f = formula "foo" do
+        url "foo-1.0"
+
+        def pour_bottle?
+          false
+        end
+      end
+
+      expect(f).not_to pour_bottle
+    end
+
+    it "returns true if set to true" do
+      f = formula "foo" do
+        url "foo-1.0"
+
+        def pour_bottle?
+          true
+        end
+      end
+
+      expect(f).to pour_bottle
+    end
+
+    it "returns false if set to false via DSL" do
+      f = formula "foo" do
+        url "foo-1.0"
+
+        pour_bottle? do
+          reason "false reason"
+          satisfy { (var == etc) }
+        end
+      end
+
+      expect(f).not_to pour_bottle
+    end
+
+    it "returns true if set to true via DSL" do
+      f = formula "foo" do
+        url "foo-1.0"
+
+        pour_bottle? do
+          reason "true reason"
+          satisfy { true }
+        end
+      end
+
+      expect(f).to pour_bottle
+    end
+  end
+
+  describe "alias changes" do
+    let(:f) do
+      formula "formula_name", alias_path: alias_path do
+        url "foo-1.0"
+      end
+    end
+
+    let(:new_formula) do
+      formula "new_formula_name", alias_path: alias_path do
+        url "foo-1.1"
+      end
+    end
+
+    let(:tab) { Tab.empty }
+    let(:alias_path) { "#{CoreTap.instance.alias_dir}/bar" }
+
+    before(:each) do
+      allow(described_class).to receive(:installed).and_return([f])
+
+      f.build = tab
+      new_formula.build = tab
+    end
+
+    specify "alias changes when not installed with alias" do
+      tab.source["path"] = Formulary.core_path(f.name).to_s
+
+      expect(f.current_installed_alias_target).to be nil
+      expect(f.latest_formula).to eq(f)
+      expect(f).not_to have_changed_installed_alias_target
+      expect(f).not_to supersede_an_installed_formula
+      expect(f).not_to have_changed_alias
+      expect(f.old_installed_formulae).to be_empty
+    end
+
+    specify "alias changes when not changed" do
+      tab.source["path"] = alias_path
+      stub_formula_loader(f, alias_path)
+
+      expect(f.current_installed_alias_target).to eq(f)
+      expect(f.latest_formula).to eq(f)
+      expect(f).not_to have_changed_installed_alias_target
+      expect(f).not_to supersede_an_installed_formula
+      expect(f).not_to have_changed_alias
+      expect(f.old_installed_formulae).to be_empty
+    end
+
+    specify "alias changes when new alias target" do
+      tab.source["path"] = alias_path
+      stub_formula_loader(new_formula, alias_path)
+
+      expect(f.current_installed_alias_target).to eq(new_formula)
+      expect(f.latest_formula).to eq(new_formula)
+      expect(f).to have_changed_installed_alias_target
+      expect(f).not_to supersede_an_installed_formula
+      expect(f).to have_changed_alias
+      expect(f.old_installed_formulae).to be_empty
+    end
+
+    specify "alias changes when old formulae installed" do
+      tab.source["path"] = alias_path
+      stub_formula_loader(new_formula, alias_path)
+
+      expect(new_formula.current_installed_alias_target).to eq(new_formula)
+      expect(new_formula.latest_formula).to eq(new_formula)
+      expect(new_formula).not_to have_changed_installed_alias_target
+      expect(new_formula).to supersede_an_installed_formula
+      expect(new_formula).to have_changed_alias
+      expect(new_formula.old_installed_formulae).to eq([f])
+    end
+  end
+
+  describe "#outdated_kegs" do
+    let(:outdated_prefix) { (HOMEBREW_CELLAR/"#{f.name}/1.11") }
+    let(:same_prefix) { (HOMEBREW_CELLAR/"#{f.name}/1.20") }
+    let(:greater_prefix) { (HOMEBREW_CELLAR/"#{f.name}/1.21") }
+    let(:head_prefix) { (HOMEBREW_CELLAR/"#{f.name}/HEAD") }
+    let(:old_alias_target_prefix) { (HOMEBREW_CELLAR/"#{old_formula.name}/1.0") }
+
+    let(:f) do
+      formula do
+        url "foo"
+        version "1.20"
+      end
+    end
+
+    let(:old_formula) do
+      formula "foo@1" do
+        url "foo-1.0"
+      end
+    end
+
+    let(:new_formula) do
+      formula "foo@2" do
+        url "foo-2.0"
+      end
+    end
+
+    let(:alias_path) { "#{f.tap.alias_dir}/bar" }
+
+    def setup_tab_for_prefix(prefix, options = {})
+      prefix.mkpath
+      tab = Tab.empty
+      tab.tabfile = prefix/Tab::FILENAME
+      tab.source["path"] = options[:path].to_s if options[:path]
+      tab.source["tap"] = options[:tap] if options[:tap]
+      tab.source["versions"] = options[:versions] if options[:versions]
+      tab.source_modified_time = options[:source_modified_time].to_i
+      tab.write unless options[:no_write]
+      tab
+    end
+
+    def reset_outdated_kegs
+      f.instance_variable_set(:@outdated_kegs, nil)
+    end
+
+    example "greater different tap installed" do
+      setup_tab_for_prefix(greater_prefix, tap: "user/repo")
+      expect(f.outdated_kegs).to be_empty
+    end
+
+    example "greater same tap installed" do
+      f.instance_variable_set(:@tap, CoreTap.instance)
+      setup_tab_for_prefix(greater_prefix, tap: "homebrew/core")
+      expect(f.outdated_kegs).to be_empty
+    end
+
+    example "outdated different tap installed" do
+      setup_tab_for_prefix(outdated_prefix, tap: "user/repo")
+      expect(f.outdated_kegs).not_to be_empty
+    end
+
+    example "outdated same tap installed" do
+      f.instance_variable_set(:@tap, CoreTap.instance)
+      setup_tab_for_prefix(outdated_prefix, tap: "homebrew/core")
+      expect(f.outdated_kegs).not_to be_empty
+    end
+
+    example "outdated follow alias and alias unchanged" do
+      f.follow_installed_alias = true
+      f.build = setup_tab_for_prefix(same_prefix, path: alias_path)
+      stub_formula_loader(f, alias_path)
+      expect(f.outdated_kegs).to be_empty
+    end
+
+    example "outdated follow alias and alias changed and new target not installed" do
+      f.follow_installed_alias = true
+      f.build = setup_tab_for_prefix(same_prefix, path: alias_path)
+      stub_formula_loader(new_formula, alias_path)
+      expect(f.outdated_kegs).not_to be_empty
+    end
+
+    example "outdated follow alias and alias changed and new target installed" do
+      f.follow_installed_alias = true
+      f.build = setup_tab_for_prefix(same_prefix, path: alias_path)
+      stub_formula_loader(new_formula, alias_path)
+      setup_tab_for_prefix(new_formula.prefix)
+      expect(f.outdated_kegs).to be_empty
+    end
+
+    example "outdated no follow alias and alias unchanged" do
+      f.follow_installed_alias = false
+      f.build = setup_tab_for_prefix(same_prefix, path: alias_path)
+      stub_formula_loader(f, alias_path)
+      expect(f.outdated_kegs).to be_empty
+    end
+
+    example "outdated no follow alias and alias changed" do
+      f.follow_installed_alias = false
+      f.build = setup_tab_for_prefix(same_prefix, path: alias_path)
+
+      f2 = formula "foo@2" do
+        url "foo-2.0"
+      end
+
+      stub_formula_loader(f2, alias_path)
+      expect(f.outdated_kegs).to be_empty
+    end
+
+    example "outdated old alias targets installed" do
+      f = formula alias_path: alias_path do
+        url "foo-1.0"
+      end
+
+      tab = setup_tab_for_prefix(old_alias_target_prefix, path: alias_path)
+      old_formula.build = tab
+      allow(described_class).to receive(:installed).and_return([old_formula])
+      expect(f.outdated_kegs).not_to be_empty
+    end
+
+    example "outdated old alias targets not installed" do
+      f = formula alias_path: alias_path do
+        url "foo-1.0"
+      end
+
+      tab = setup_tab_for_prefix(old_alias_target_prefix, path: old_formula.path)
+      old_formula.build = tab
+      allow(described_class).to receive(:installed).and_return([old_formula])
+      expect(f.outdated_kegs).to be_empty
+    end
+
+    example "outdated same head installed" do
+      f.instance_variable_set(:@tap, CoreTap.instance)
+      setup_tab_for_prefix(head_prefix, tap: "homebrew/core")
+      expect(f.outdated_kegs).to be_empty
+    end
+
+    example "outdated different head installed" do
+      f.instance_variable_set(:@tap, CoreTap.instance)
+      setup_tab_for_prefix(head_prefix, tap: "user/repo")
+      expect(f.outdated_kegs).to be_empty
+    end
+
+    example "outdated mixed taps greater version installed" do
+      f.instance_variable_set(:@tap, CoreTap.instance)
+      setup_tab_for_prefix(outdated_prefix, tap: "homebrew/core")
+      setup_tab_for_prefix(greater_prefix, tap: "user/repo")
+
+      expect(f.outdated_kegs).to be_empty
+
+      setup_tab_for_prefix(greater_prefix, tap: "homebrew/core")
+      reset_outdated_kegs
+
+      expect(f.outdated_kegs).to be_empty
+    end
+
+    example "outdated mixed taps outdated version installed" do
+      f.instance_variable_set(:@tap, CoreTap.instance)
+
+      extra_outdated_prefix = HOMEBREW_CELLAR/f.name/"1.0"
+
+      setup_tab_for_prefix(outdated_prefix)
+      setup_tab_for_prefix(extra_outdated_prefix, tap: "homebrew/core")
+      reset_outdated_kegs
+
+      expect(f.outdated_kegs).not_to be_empty
+
+      setup_tab_for_prefix(outdated_prefix, tap: "user/repo")
+      reset_outdated_kegs
+
+      expect(f.outdated_kegs).not_to be_empty
+    end
+
+    example "outdated same version tap installed" do
+      f.instance_variable_set(:@tap, CoreTap.instance)
+      setup_tab_for_prefix(same_prefix, tap: "homebrew/core")
+
+      expect(f.outdated_kegs).to be_empty
+
+      setup_tab_for_prefix(same_prefix, tap: "user/repo")
+      reset_outdated_kegs
+
+      expect(f.outdated_kegs).to be_empty
+    end
+
+    example "outdated installed head less than stable" do
+      tab = setup_tab_for_prefix(head_prefix, versions: { "stable" => "1.0" })
+
+      expect(f.outdated_kegs).not_to be_empty
+
+      tab.source["versions"] = { "stable" => f.version.to_s }
+      tab.write
+      reset_outdated_kegs
+
+      expect(f.outdated_kegs).to be_empty
+    end
+
+    describe ":fetch_head" do
+      let(:f) do
+        repo = testball_repo
+        formula "testball" do
+          url "foo"
+          version "2.10"
+          head "file://#{repo}", using: :git
+        end
+      end
+      let(:testball_repo) { HOMEBREW_PREFIX/"testball_repo" }
+
+      example do
+        begin
+          outdated_stable_prefix = HOMEBREW_CELLAR/"testball/1.0"
+          head_prefix_a = HOMEBREW_CELLAR/"testball/HEAD"
+          head_prefix_b = HOMEBREW_CELLAR/"testball/HEAD-aaaaaaa_1"
+          head_prefix_c = HOMEBREW_CELLAR/"testball/HEAD-18a7103"
+
+          setup_tab_for_prefix(outdated_stable_prefix)
+          tab_a = setup_tab_for_prefix(head_prefix_a, versions: { "stable" => "1.0" })
+          setup_tab_for_prefix(head_prefix_b)
+
+          testball_repo.mkdir
+          testball_repo.cd do
+            FileUtils.touch "LICENSE"
+
+            shutup do
+              system("git", "init")
+              system("git", "add", "--all")
+              system("git", "commit", "-m", "Initial commit")
+            end
+          end
+
+          expect(f.outdated_kegs(fetch_head: true)).not_to be_empty
+
+          tab_a.source["versions"] = { "stable" => f.version.to_s }
+          tab_a.write
+          reset_outdated_kegs
+          expect(f.outdated_kegs(fetch_head: true)).not_to be_empty
+
+          head_prefix_a.rmtree
+          reset_outdated_kegs
+          expect(f.outdated_kegs(fetch_head: true)).not_to be_empty
+
+          setup_tab_for_prefix(head_prefix_c, source_modified_time: 1)
+          reset_outdated_kegs
+          expect(f.outdated_kegs(fetch_head: true)).to be_empty
+        ensure
+          testball_repo.rmtree if testball_repo.exist?
+        end
+      end
+    end
+
+    describe "with changed version scheme" do
+      let(:f) do
+        formula "testball" do
+          url "foo"
+          version "20141010"
+          version_scheme 1
+        end
+      end
+
+      example do
+        prefix = HOMEBREW_CELLAR/"testball/0.1"
+        setup_tab_for_prefix(prefix, versions: { "stable" => "0.1" })
+
+        expect(f.outdated_kegs).not_to be_empty
+      end
+    end
+
+    describe "with mixed version schemes" do
+      let(:f) do
+        formula "testball" do
+          url "foo"
+          version "20141010"
+          version_scheme 3
+        end
+      end
+
+      example do
+        prefix_a = HOMEBREW_CELLAR/"testball/20141009"
+        setup_tab_for_prefix(prefix_a, versions: { "stable" => "20141009", "version_scheme" => 1 })
+
+        prefix_b = HOMEBREW_CELLAR/"testball/2.14"
+        setup_tab_for_prefix(prefix_b, versions: { "stable" => "2.14", "version_scheme" => 2 })
+
+        expect(f.outdated_kegs).not_to be_empty
+        reset_outdated_kegs
+
+        prefix_c = HOMEBREW_CELLAR/"testball/20141009"
+        setup_tab_for_prefix(prefix_c, versions: { "stable" => "20141009", "version_scheme" => 3 })
+
+        expect(f.outdated_kegs).not_to be_empty
+        reset_outdated_kegs
+
+        prefix_d = HOMEBREW_CELLAR/"testball/20141011"
+        setup_tab_for_prefix(prefix_d, versions: { "stable" => "20141009", "version_scheme" => 3 })
+        expect(f.outdated_kegs).to be_empty
+      end
+    end
+
+    describe "with version scheme" do
+      let(:f) do
+        formula "testball" do
+          url "foo"
+          version "1.0"
+          version_scheme 2
+        end
+      end
+
+      example do
+        head_prefix = HOMEBREW_CELLAR/"testball/HEAD"
+
+        setup_tab_for_prefix(head_prefix, versions: { "stable" => "1.0", "version_scheme" => 1 })
+        expect(f.outdated_kegs).not_to be_empty
+
+        reset_outdated_kegs
+        head_prefix.rmtree
+
+        setup_tab_for_prefix(head_prefix, versions: { "stable" => "1.0", "version_scheme" => 2 })
+        expect(f.outdated_kegs).to be_empty
+      end
+    end
+  end
+end
diff --git a/Library/Homebrew/test/formula_test.rb b/Library/Homebrew/test/formula_test.rb
deleted file mode 100644
index 81022d220..000000000
--- a/Library/Homebrew/test/formula_test.rb
+++ /dev/null
@@ -1,1210 +0,0 @@
-require "testing_env"
-require "test/support/fixtures/testball"
-require "formula"
-
-class FormulaTests < Homebrew::TestCase
-  def test_formula_instantiation
-    klass = Class.new(Formula) { url "http://example.com/foo-1.0.tar.gz" }
-    name = "formula_name"
-    path = Formulary.core_path(name)
-    spec = :stable
-
-    f = klass.new(name, path, spec)
-    assert_equal name, f.name
-    assert_equal name, f.specified_name
-    assert_equal name, f.full_name
-    assert_equal name, f.full_specified_name
-    assert_equal path, f.path
-    assert_nil f.alias_path
-    assert_nil f.alias_name
-    assert_nil f.full_alias_name
-    assert_raises(ArgumentError) { klass.new }
-  end
-
-  def test_formula_instantiation_with_alias
-    klass = Class.new(Formula) { url "http://example.com/foo-1.0.tar.gz" }
-    name = "formula_name"
-    path = Formulary.core_path(name)
-    spec = :stable
-    alias_name = "baz@1"
-    alias_path = CoreTap.instance.alias_dir/alias_name
-
-    f = klass.new(name, path, spec, alias_path: alias_path)
-    assert_equal name, f.name
-    assert_equal name, f.full_name
-    assert_equal path, f.path
-    assert_equal alias_path, f.alias_path
-    assert_equal alias_name, f.alias_name
-    assert_equal alias_name, f.specified_name
-    assert_equal alias_name, f.full_alias_name
-    assert_equal alias_name, f.full_specified_name
-    assert_raises(ArgumentError) { klass.new }
-  end
-
-  def test_tap_formula_instantiation
-    tap = Tap.new("foo", "bar")
-    klass = Class.new(Formula) { url "baz-1.0" }
-    name = "baz"
-    full_name = "#{tap.user}/#{tap.repo}/#{name}"
-    path = tap.path/"Formula/#{name}.rb"
-    spec = :stable
-
-    f = klass.new(name, path, spec)
-    assert_equal name, f.name
-    assert_equal name, f.specified_name
-    assert_equal full_name, f.full_name
-    assert_equal full_name, f.full_specified_name
-    assert_equal path, f.path
-    assert_nil f.alias_path
-    assert_nil f.alias_name
-    assert_nil f.full_alias_name
-    assert_raises(ArgumentError) { klass.new }
-  end
-
-  def test_tap_formula_instantiation_with_alias
-    tap = Tap.new("foo", "bar")
-    klass = Class.new(Formula) { url "baz-1.0" }
-    name = "baz"
-    full_name = "#{tap.user}/#{tap.repo}/#{name}"
-    path = tap.path/"Formula/#{name}.rb"
-    spec = :stable
-    alias_name = "baz@1"
-    full_alias_name = "#{tap.user}/#{tap.repo}/#{alias_name}"
-    alias_path = CoreTap.instance.alias_dir/alias_name
-
-    f = klass.new(name, path, spec, alias_path: alias_path)
-    assert_equal name, f.name
-    assert_equal full_name, f.full_name
-    assert_equal path, f.path
-    assert_equal alias_path, f.alias_path
-    assert_equal alias_name, f.alias_name
-    assert_equal alias_name, f.specified_name
-    assert_equal full_alias_name, f.full_alias_name
-    assert_equal full_alias_name, f.full_specified_name
-    assert_raises(ArgumentError) { klass.new }
-  end
-
-  def test_follow_installed_alias
-    f = formula { url "foo-1.0" }
-    assert_predicate f, :follow_installed_alias?
-
-    f.follow_installed_alias = true
-    assert_predicate f, :follow_installed_alias?
-
-    f.follow_installed_alias = false
-    refute_predicate f, :follow_installed_alias?
-  end
-
-  def test_installed_alias_with_core
-    f = formula { url "foo-1.0" }
-
-    build_values_with_no_installed_alias = [
-      nil,
-      BuildOptions.new({}, {}),
-      Tab.new(source: { "path" => f.path.to_s }),
-    ]
-
-    build_values_with_no_installed_alias.each do |build|
-      f.build = build
-      assert_nil f.installed_alias_path
-      assert_nil f.installed_alias_name
-      assert_nil f.full_installed_alias_name
-      assert_equal f.name, f.installed_specified_name
-      assert_equal f.name, f.full_installed_specified_name
-    end
-
-    alias_name = "bar"
-    alias_path = "#{CoreTap.instance.alias_dir}/#{alias_name}"
-    f.build = Tab.new(source: { "path" => alias_path })
-    assert_equal alias_path, f.installed_alias_path
-    assert_equal alias_name, f.installed_alias_name
-    assert_equal alias_name, f.full_installed_alias_name
-    assert_equal alias_name, f.installed_specified_name
-    assert_equal alias_name, f.full_installed_specified_name
-  end
-
-  def test_installed_alias_with_tap
-    tap = Tap.new("user", "repo")
-    name = "foo"
-    path = "#{tap.path}/Formula/#{name}.rb"
-    f = formula(name, path) { url "foo-1.0" }
-
-    build_values_with_no_installed_alias = [
-      nil,
-      BuildOptions.new({}, {}),
-      Tab.new(source: { "path" => f.path }),
-    ]
-
-    build_values_with_no_installed_alias.each do |build|
-      f.build = build
-      assert_nil f.installed_alias_path
-      assert_nil f.installed_alias_name
-      assert_nil f.full_installed_alias_name
-      assert_equal f.name, f.installed_specified_name
-      assert_equal f.full_name, f.full_installed_specified_name
-    end
-
-    alias_name = "bar"
-    full_alias_name = "#{tap.user}/#{tap.repo}/#{alias_name}"
-    alias_path = "#{tap.alias_dir}/#{alias_name}"
-    f.build = Tab.new(source: { "path" => alias_path })
-    assert_equal alias_path, f.installed_alias_path
-    assert_equal alias_name, f.installed_alias_name
-    assert_equal full_alias_name, f.full_installed_alias_name
-    assert_equal alias_name, f.installed_specified_name
-    assert_equal full_alias_name, f.full_installed_specified_name
-  end
-
-  def test_prefix
-    f = Testball.new
-    assert_equal HOMEBREW_CELLAR/f.name/"0.1", f.prefix
-    assert_kind_of Pathname, f.prefix
-  end
-
-  def test_revised_prefix
-    f = Class.new(Testball) { revision 1 }.new
-    assert_equal HOMEBREW_CELLAR/f.name/"0.1_1", f.prefix
-  end
-
-  def test_any_version_installed?
-    f = formula do
-      url "foo"
-      version "1.0"
-    end
-    refute_predicate f, :any_version_installed?
-    prefix = HOMEBREW_CELLAR+f.name+"0.1"
-    prefix.mkpath
-    FileUtils.touch prefix+Tab::FILENAME
-    assert_predicate f, :any_version_installed?
-  ensure
-    f.rack.rmtree
-  end
-
-  def test_migration_needed
-    f = Testball.new("newname")
-    f.instance_variable_set(:@oldname, "oldname")
-    f.instance_variable_set(:@tap, CoreTap.instance)
-
-    oldname_prefix = HOMEBREW_CELLAR/"oldname/2.20"
-    newname_prefix = HOMEBREW_CELLAR/"newname/2.10"
-    oldname_prefix.mkpath
-    oldname_tab = Tab.empty
-    oldname_tab.tabfile = oldname_prefix.join("INSTALL_RECEIPT.json")
-    oldname_tab.write
-
-    refute_predicate f, :migration_needed?
-
-    oldname_tab.tabfile.unlink
-    oldname_tab.source["tap"] = "homebrew/core"
-    oldname_tab.write
-
-    assert_predicate f, :migration_needed?
-
-    newname_prefix.mkpath
-
-    refute_predicate f, :migration_needed?
-  ensure
-    oldname_prefix.parent.rmtree
-    newname_prefix.parent.rmtree
-  end
-
-  def test_installed?
-    f = Testball.new
-    f.stubs(:installed_prefix).returns(stub(directory?: false))
-    refute_predicate f, :installed?
-
-    f.stubs(:installed_prefix).returns(
-      stub(directory?: true, children: [])
-    )
-    refute_predicate f, :installed?
-
-    f.stubs(:installed_prefix).returns(
-      stub(directory?: true, children: [stub])
-    )
-    assert_predicate f, :installed?
-  end
-
-  def test_installed_prefix
-    f = Testball.new
-    assert_equal f.prefix, f.installed_prefix
-  end
-
-  def test_installed_prefix_head_installed
-    f = formula do
-      head "foo"
-      devel do
-        url "foo"
-        version "1.0"
-      end
-    end
-    prefix = HOMEBREW_CELLAR+f.name+f.head.version
-    prefix.mkpath
-    assert_equal prefix, f.installed_prefix
-  ensure
-    f.rack.rmtree
-  end
-
-  def test_installed_prefix_devel_installed
-    f = formula do
-      head "foo"
-      devel do
-        url "foo"
-        version "1.0"
-      end
-    end
-    prefix = HOMEBREW_CELLAR+f.name+f.devel.version
-    prefix.mkpath
-    assert_equal prefix, f.installed_prefix
-  ensure
-    f.rack.rmtree
-  end
-
-  def test_installed_prefix_stable_installed
-    f = formula do
-      head "foo"
-      devel do
-        url "foo"
-        version "1.0-devel"
-      end
-    end
-    prefix = HOMEBREW_CELLAR+f.name+f.version
-    prefix.mkpath
-    assert_equal prefix, f.installed_prefix
-  ensure
-    f.rack.rmtree
-  end
-
-  def test_installed_prefix_outdated_stable_head_installed
-    f = formula do
-      url "foo"
-      version "1.9"
-      head "foo"
-    end
-
-    head_prefix = HOMEBREW_CELLAR/"#{f.name}/HEAD"
-    head_prefix.mkpath
-    tab = Tab.empty
-    tab.tabfile = head_prefix.join("INSTALL_RECEIPT.json")
-    tab.source["versions"] = { "stable" => "1.0" }
-    tab.write
-
-    assert_equal HOMEBREW_CELLAR/"#{f.name}/#{f.version}", f.installed_prefix
-  ensure
-    f.rack.rmtree
-  end
-
-  def test_installed_prefix_outdated_devel_head_installed
-    f = formula do
-      url "foo"
-      version "1.9"
-      devel do
-        url "foo"
-        version "2.1"
-      end
-    end
-
-    head_prefix = HOMEBREW_CELLAR/"#{f.name}/HEAD"
-    head_prefix.mkpath
-    tab = Tab.empty
-    tab.tabfile = head_prefix.join("INSTALL_RECEIPT.json")
-    tab.source["versions"] = { "stable" => "1.9", "devel" => "2.0" }
-    tab.write
-
-    assert_equal HOMEBREW_CELLAR/"#{f.name}/#{f.version}", f.installed_prefix
-  ensure
-    f.rack.rmtree
-  end
-
-  def test_installed_prefix_head
-    f = formula("test", Pathname.new(__FILE__).expand_path, :head) do
-      head "foo"
-      devel do
-        url "foo"
-        version "1.0-devel"
-      end
-    end
-    prefix = HOMEBREW_CELLAR+f.name+f.head.version
-    assert_equal prefix, f.installed_prefix
-  end
-
-  def test_installed_prefix_devel
-    f = formula("test", Pathname.new(__FILE__).expand_path, :devel) do
-      head "foo"
-      devel do
-        url "foo"
-        version "1.0-devel"
-      end
-    end
-    prefix = HOMEBREW_CELLAR+f.name+f.devel.version
-    assert_equal prefix, f.installed_prefix
-  end
-
-  def test_latest_head_prefix
-    f = Testball.new
-
-    stamps_with_revisions = [[111111, 1], [222222, 1], [222222, 2], [222222, 0]]
-
-    stamps_with_revisions.each do |stamp, revision|
-      version = "HEAD-#{stamp}"
-      version += "_#{revision}" if revision > 0
-      prefix = f.rack.join(version)
-      prefix.mkpath
-
-      tab = Tab.empty
-      tab.tabfile = prefix.join("INSTALL_RECEIPT.json")
-      tab.source_modified_time = stamp
-      tab.write
-    end
-
-    prefix = HOMEBREW_CELLAR/"#{f.name}/HEAD-222222_2"
-    assert_equal prefix, f.latest_head_prefix
-  ensure
-    f.rack.rmtree
-  end
-
-  def test_equality
-    x = Testball.new
-    y = Testball.new
-    assert_equal x, y
-    assert_eql x, y
-    assert_equal x.hash, y.hash
-  end
-
-  def test_inequality
-    x = Testball.new("foo")
-    y = Testball.new("bar")
-    refute_equal x, y
-    refute_eql x, y
-    refute_equal x.hash, y.hash
-  end
-
-  def test_comparison_with_non_formula_objects_does_not_raise
-    refute_equal Testball.new, Object.new
-  end
-
-  def test_sort_operator
-    assert_nil Testball.new <=> Object.new
-  end
-
-  def test_alias_paths_with_build_options
-    alias_path = CoreTap.instance.alias_dir/"another_name"
-    f = formula(alias_path: alias_path) { url "foo-1.0" }
-    f.build = BuildOptions.new({}, {})
-    assert_equal alias_path, f.alias_path
-    assert_nil f.installed_alias_path
-  end
-
-  def test_alias_paths_with_tab_with_non_alias_source_path
-    alias_path = CoreTap.instance.alias_dir/"another_name"
-    source_path = CoreTap.instance.formula_dir/"another_other_name"
-    f = formula(alias_path: alias_path) { url "foo-1.0" }
-    f.build = Tab.new(source: { "path" => source_path.to_s })
-    assert_equal alias_path, f.alias_path
-    assert_nil f.installed_alias_path
-  end
-
-  def test_alias_paths_with_tab_with_alias_source_path
-    alias_path = CoreTap.instance.alias_dir/"another_name"
-    source_path = CoreTap.instance.alias_dir/"another_other_name"
-    f = formula(alias_path: alias_path) { url "foo-1.0" }
-    f.build = Tab.new(source: { "path" => source_path.to_s })
-    assert_equal alias_path, f.alias_path
-    assert_equal source_path.to_s, f.installed_alias_path
-  end
-
-  def test_installed_with_alias_path_with_nil
-    assert_predicate Formula.installed_with_alias_path(nil), :empty?
-  end
-
-  def test_installed_with_alias_path_with_a_path
-    alias_path = "#{CoreTap.instance.alias_dir}/alias"
-    different_alias_path = "#{CoreTap.instance.alias_dir}/another_alias"
-
-    formula_with_alias = formula("foo") { url "foo-1.0" }
-    formula_with_alias.build = Tab.empty
-    formula_with_alias.build.source["path"] = alias_path
-
-    formula_without_alias = formula("bar") { url "bar-1.0" }
-    formula_without_alias.build = Tab.empty
-    formula_without_alias.build.source["path"] = formula_without_alias.path.to_s
-
-    formula_with_different_alias = formula("baz") { url "baz-1.0" }
-    formula_with_different_alias.build = Tab.empty
-    formula_with_different_alias.build.source["path"] = different_alias_path
-
-    formulae = [
-      formula_with_alias,
-      formula_without_alias,
-      formula_with_different_alias,
-    ]
-
-    Formula.stubs(:installed).returns(formulae)
-    assert_equal [formula_with_alias], Formula.installed_with_alias_path(alias_path)
-  end
-
-  def test_formula_spec_integration
-    f = formula do
-      homepage "http://example.com"
-      url "http://example.com/test-0.1.tbz"
-      mirror "http://example.org/test-0.1.tbz"
-      sha256 TEST_SHA256
-
-      head "http://example.com/test.git", tag: "foo"
-
-      devel do
-        url "http://example.com/test-0.2.tbz"
-        mirror "http://example.org/test-0.2.tbz"
-        sha256 TEST_SHA256
-      end
-    end
-
-    assert_equal "http://example.com", f.homepage
-    assert_version_equal "0.1", f.version
-    assert_predicate f, :stable?
-
-    assert_version_equal "0.1", f.stable.version
-    assert_version_equal "0.2", f.devel.version
-    assert_version_equal "HEAD", f.head.version
-  end
-
-  def test_formula_active_spec=
-    f = formula do
-      url "foo"
-      version "1.0"
-      revision 1
-
-      devel do
-        url "foo"
-        version "1.0beta"
-      end
-    end
-    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.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.active_spec = :head }
-  end
-
-  def test_path
-    name = "foo-bar"
-    assert_equal Pathname.new("#{HOMEBREW_LIBRARY}/Taps/homebrew/homebrew-core/Formula/#{name}.rb"), Formulary.core_path(name)
-  end
-
-  def test_class_specs_are_always_initialized
-    f = formula { url "foo-1.0" }
-
-    %w[stable devel head].each do |spec|
-      assert_kind_of SoftwareSpec, f.class.send(spec)
-    end
-  end
-
-  def test_incomplete_instance_specs_are_not_accessible
-    f = formula { url "foo-1.0" }
-
-    %w[devel head].each { |spec| assert_nil f.send(spec) }
-  end
-
-  def test_honors_attributes_declared_before_specs
-    f = formula do
-      url "foo-1.0"
-      depends_on "foo"
-      devel { url "foo-1.1" }
-    end
-
-    %w[stable devel head].each do |spec|
-      assert_equal "foo", f.class.send(spec).deps.first.name
-    end
-  end
-
-  def test_simple_version
-    assert_equal PkgVersion.parse("1.0"), formula { url "foo-1.0.bar" }.pkg_version
-  end
-
-  def test_version_with_revision
-    f = formula do
-      url "foo-1.0.bar"
-      revision 1
-    end
-
-    assert_equal PkgVersion.parse("1.0_1"), f.pkg_version
-  end
-
-  def test_head_uses_revisions
-    f = formula("test", Pathname.new(__FILE__).expand_path, :head) do
-      url "foo-1.0.bar"
-      revision 1
-      head "foo"
-    end
-
-    assert_equal PkgVersion.parse("HEAD_1"), f.pkg_version
-  end
-
-  def test_update_head_version
-    initial_env = ENV.to_hash
-
-    f = formula do
-      head "foo", using: :git
-    end
-
-    cached_location = f.head.downloader.cached_location
-    cached_location.mkpath
-
-    %w[AUTHOR COMMITTER].each do |role|
-      ENV["GIT_#{role}_NAME"] = "brew tests"
-      ENV["GIT_#{role}_EMAIL"] = "brew-tests@localhost"
-      ENV["GIT_#{role}_DATE"] = "Thu May 21 00:04:11 2009 +0100"
-    end
-
-    cached_location.cd do
-      FileUtils.touch "LICENSE"
-      shutup do
-        system "git", "init"
-        system "git", "add", "--all"
-        system "git", "commit", "-m", "Initial commit"
-      end
-    end
-
-    f.update_head_version
-    assert_equal Version.create("HEAD-5658946"), f.head.version
-  ensure
-    ENV.replace(initial_env)
-    cached_location.rmtree
-  end
-
-  def test_legacy_options
-    f = formula do
-      url "foo-1.0"
-
-      def options
-        [["--foo", "desc"], ["--bar", "desc"]]
-      end
-
-      option "baz"
-    end
-
-    assert f.option_defined?("foo")
-    assert f.option_defined?("bar")
-    assert f.option_defined?("baz")
-  end
-
-  def test_desc
-    f = formula do
-      desc "a formula"
-      url "foo-1.0"
-    end
-
-    assert_equal "a formula", f.desc
-  end
-
-  def test_post_install_defined
-    f1 = formula do
-      url "foo-1.0"
-
-      def post_install; end
-    end
-
-    f2 = formula do
-      url "foo-1.0"
-    end
-
-    assert f1.post_install_defined?
-    refute f2.post_install_defined?
-  end
-
-  def test_test_defined
-    f1 = formula do
-      url "foo-1.0"
-
-      def test; end
-    end
-
-    f2 = formula do
-      url "foo-1.0"
-    end
-
-    assert f1.test_defined?
-    refute f2.test_defined?
-  end
-
-  def test_test_fixtures
-    f1 = formula do
-      url "foo-1.0"
-    end
-
-    assert_equal Pathname.new("#{HOMEBREW_LIBRARY_PATH}/test/support/fixtures/foo"),
-      f1.test_fixtures("foo")
-  end
-
-  def test_dependencies
-    stub_formula_loader formula("f1") { url "f1-1.0" }
-    stub_formula_loader formula("f2") { url "f2-1.0" }
-
-    f3 = formula("f3") do
-      url "f3-1.0"
-      depends_on "f1" => :build
-      depends_on "f2"
-    end
-    stub_formula_loader f3
-
-    f4 = formula("f4") do
-      url "f4-1.0"
-      depends_on "f1"
-    end
-    stub_formula_loader f4
-
-    f5 = formula("f5") do
-      url "f5-1.0"
-      depends_on "f3" => :build
-      depends_on "f4"
-    end
-
-    assert_equal %w[f3 f4], f5.deps.map(&:name)
-    assert_equal %w[f1 f2 f3 f4], f5.recursive_dependencies.map(&:name)
-    assert_equal %w[f1 f4], f5.runtime_dependencies.map(&:name)
-  end
-
-  def test_runtime_dependencies_with_optional_deps_from_tap
-    tap_loader = mock
-    tap_loader.stubs(:get_formula).raises(RuntimeError, "tried resolving tap formula")
-    Formulary.stubs(:loader_for).with("foo/bar/f1", from: nil).returns(tap_loader)
-
-    stub_formula_loader formula("f2") { url "f2-1.0" }, "baz/qux/f2"
-
-    f3 = formula("f3") do
-      url "f3-1.0"
-      depends_on "foo/bar/f1" => :optional
-      depends_on "baz/qux/f2"
-    end
-
-    # f1 shouldn't be loaded by default.
-    # If it is, an exception will be raised.
-    assert_equal %w[baz/qux/f2], f3.runtime_dependencies.map(&:name)
-
-    # If --with-f1, f1 should be loaded.
-    stub_formula_loader formula("f1") { url "f1-1.0" }, "foo/bar/f1"
-    f3.build = BuildOptions.new(Options.create(%w[--with-f1]), f3.options)
-    assert_equal %w[foo/bar/f1 baz/qux/f2], f3.runtime_dependencies.map(&:name)
-  end
-
-  def test_to_hash
-    f1 = formula("foo") do
-      url "foo-1.0"
-    end
-
-    h = f1.to_hash
-    assert h.is_a?(Hash), "Formula#to_hash should return a Hash"
-    assert_equal "foo", h["name"]
-    assert_equal "foo", h["full_name"]
-    assert_equal "1.0", h["versions"]["stable"]
-  end
-
-  def test_to_hash_bottle
-    f1 = formula("foo") do
-      url "foo-1.0"
-
-      bottle do
-        cellar :any
-        sha256 TEST_SHA256 => Utils::Bottles.tag
-      end
-    end
-
-    h = f1.to_hash
-    assert h.is_a?(Hash), "Formula#to_hash should return a Hash"
-    assert h["versions"]["bottle"], "The hash should say the formula is bottled"
-  end
-
-  def test_eligible_kegs_for_cleanup
-    f1 = Class.new(Testball) { version "0.1" }.new
-    f2 = Class.new(Testball) { version "0.2" }.new
-    f3 = Class.new(Testball) { version "0.3" }.new
-
-    shutup do
-      f1.brew { f1.install }
-      f2.brew { f2.install }
-      f3.brew { f3.install }
-    end
-
-    assert_predicate f1, :installed?
-    assert_predicate f2, :installed?
-    assert_predicate f3, :installed?
-
-    assert_equal f3.installed_kegs.sort_by(&:version)[0..1],
-                 f3.eligible_kegs_for_cleanup.sort_by(&:version)
-  ensure
-    [f1, f2, f3].each(&:clear_cache)
-    f3.rack.rmtree
-  end
-
-  def test_eligible_kegs_for_cleanup_keg_pinned
-    f1 = Class.new(Testball) { version "0.1" }.new
-    f2 = Class.new(Testball) { version "0.2" }.new
-    f3 = Class.new(Testball) { version "0.3" }.new
-
-    shutup do
-      f1.brew { f1.install }
-      f1.pin
-      f2.brew { f2.install }
-      f3.brew { f3.install }
-    end
-
-    assert_equal (HOMEBREW_PINNED_KEGS/f1.name).resolved_path, f1.prefix
-
-    assert_predicate f1, :installed?
-    assert_predicate f2, :installed?
-    assert_predicate f3, :installed?
-
-    assert_equal [Keg.new(f2.prefix)], shutup { f3.eligible_kegs_for_cleanup }
-  ensure
-    f1.unpin
-    [f1, f2, f3].each(&:clear_cache)
-    f3.rack.rmtree
-  end
-
-  def test_eligible_kegs_for_cleanup_head_installed
-    f = formula do
-      version "0.1"
-      head "foo"
-    end
-
-    stable_prefix = f.installed_prefix
-    stable_prefix.mkpath
-
-    [["000000_1", 1], ["111111", 2], ["111111_1", 2]].each do |pkg_version_suffix, stamp|
-      prefix = f.prefix("HEAD-#{pkg_version_suffix}")
-      prefix.mkpath
-      tab = Tab.empty
-      tab.tabfile = prefix.join("INSTALL_RECEIPT.json")
-      tab.source_modified_time = stamp
-      tab.write
-    end
-
-    eligible_kegs = f.installed_kegs - [Keg.new(f.prefix("HEAD-111111_1"))]
-    assert_equal eligible_kegs, f.eligible_kegs_for_cleanup
-  ensure
-    f.rack.rmtree
-  end
-
-  def test_pour_bottle
-    f_false = formula("foo") do
-      url "foo-1.0"
-      def pour_bottle?
-        false
-      end
-    end
-    refute f_false.pour_bottle?
-
-    f_true = formula("foo") do
-      url "foo-1.0"
-      def pour_bottle?
-        true
-      end
-    end
-    assert f_true.pour_bottle?
-  end
-
-  def test_pour_bottle_dsl
-    f_false = formula("foo") do
-      url "foo-1.0"
-      pour_bottle? do
-        reason "false reason"
-        satisfy { var == etc }
-      end
-    end
-    refute f_false.pour_bottle?
-
-    f_true = formula("foo") do
-      url "foo-1.0"
-      pour_bottle? do
-        reason "true reason"
-        satisfy { true }
-      end
-    end
-    assert f_true.pour_bottle?
-  end
-end
-
-class AliasChangeTests < Homebrew::TestCase
-  attr_reader :f, :new_formula, :tab, :alias_path
-
-  def make_formula(name, version)
-    f = formula(name, alias_path: alias_path) { url "foo-#{version}" }
-    f.build = tab
-    f
-  end
-
-  def setup
-    alias_name = "bar"
-    @alias_path = "#{CoreTap.instance.alias_dir}/#{alias_name}"
-
-    @tab = Tab.empty
-
-    @f = make_formula("formula_name", "1.0")
-    @new_formula = make_formula("new_formula_name", "1.1")
-
-    Formula.stubs(:installed).returns([f])
-  end
-
-  def test_alias_changes_when_not_installed_with_alias
-    tab.source["path"] = Formulary.core_path(f.name).to_s
-
-    assert_nil f.current_installed_alias_target
-    assert_equal f, f.latest_formula
-    refute_predicate f, :installed_alias_target_changed?
-    refute_predicate f, :supersedes_an_installed_formula?
-    refute_predicate f, :alias_changed?
-    assert_predicate f.old_installed_formulae, :empty?
-  end
-
-  def test_alias_changes_when_not_changed
-    tab.source["path"] = alias_path
-    stub_formula_loader(f, alias_path)
-
-    assert_equal f, f.current_installed_alias_target
-    assert_equal f, f.latest_formula
-    refute_predicate f, :installed_alias_target_changed?
-    refute_predicate f, :supersedes_an_installed_formula?
-    refute_predicate f, :alias_changed?
-    assert_predicate f.old_installed_formulae, :empty?
-  end
-
-  def test_alias_changes_when_new_alias_target
-    tab.source["path"] = alias_path
-    stub_formula_loader(new_formula, alias_path)
-
-    assert_equal new_formula, f.current_installed_alias_target
-    assert_equal new_formula, f.latest_formula
-    assert_predicate f, :installed_alias_target_changed?
-    refute_predicate f, :supersedes_an_installed_formula?
-    assert_predicate f, :alias_changed?
-    assert_predicate f.old_installed_formulae, :empty?
-  end
-
-  def test_alias_changes_when_old_formulae_installed
-    tab.source["path"] = alias_path
-    stub_formula_loader(new_formula, alias_path)
-
-    assert_equal new_formula, new_formula.current_installed_alias_target
-    assert_equal new_formula, new_formula.latest_formula
-    refute_predicate new_formula, :installed_alias_target_changed?
-    assert_predicate new_formula, :supersedes_an_installed_formula?
-    assert_predicate new_formula, :alias_changed?
-    assert_equal [f], new_formula.old_installed_formulae
-  end
-end
-
-class OutdatedVersionsTests < Homebrew::TestCase
-  attr_reader :outdated_prefix,
-              :same_prefix,
-              :greater_prefix,
-              :head_prefix,
-              :old_alias_target_prefix
-  attr_reader :f, :old_formula, :new_formula
-
-  def setup
-    @f = formula do
-      url "foo"
-      version "1.20"
-    end
-
-    @old_formula = formula("foo@1") { url "foo-1.0" }
-    @new_formula = formula("foo@2") { url "foo-2.0" }
-
-    @outdated_prefix = HOMEBREW_CELLAR/"#{f.name}/1.11"
-    @same_prefix = HOMEBREW_CELLAR/"#{f.name}/1.20"
-    @greater_prefix = HOMEBREW_CELLAR/"#{f.name}/1.21"
-    @head_prefix = HOMEBREW_CELLAR/"#{f.name}/HEAD"
-    @old_alias_target_prefix = HOMEBREW_CELLAR/"#{old_formula.name}/1.0"
-  end
-
-  def teardown
-    formulae = [@f, @old_formula, @new_formula]
-    formulae.map(&:rack).select(&:exist?).each(&:rmtree)
-  end
-
-  def alias_path
-    "#{@f.tap.alias_dir}/bar"
-  end
-
-  def setup_tab_for_prefix(prefix, options = {})
-    prefix.mkpath
-    tab = Tab.empty
-    tab.tabfile = prefix.join("INSTALL_RECEIPT.json")
-    tab.source["path"] = options[:path].to_s if options[:path]
-    tab.source["tap"] = options[:tap] if options[:tap]
-    tab.source["versions"] = options[:versions] if options[:versions]
-    tab.source_modified_time = options[:source_modified_time].to_i
-    tab.write unless options[:no_write]
-    tab
-  end
-
-  def reset_outdated_kegs
-    f.instance_variable_set(:@outdated_kegs, nil)
-  end
-
-  def test_greater_different_tap_installed
-    setup_tab_for_prefix(greater_prefix, tap: "user/repo")
-    assert_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_greater_same_tap_installed
-    f.instance_variable_set(:@tap, CoreTap.instance)
-    setup_tab_for_prefix(greater_prefix, tap: "homebrew/core")
-    assert_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_different_tap_installed
-    setup_tab_for_prefix(outdated_prefix, tap: "user/repo")
-    refute_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_same_tap_installed
-    f.instance_variable_set(:@tap, CoreTap.instance)
-    setup_tab_for_prefix(outdated_prefix, tap: "homebrew/core")
-    refute_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_follow_alias_and_alias_unchanged
-    f.follow_installed_alias = true
-    f.build = setup_tab_for_prefix(same_prefix, path: alias_path)
-    stub_formula_loader(f, alias_path)
-    assert_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_follow_alias_and_alias_changed_and_new_target_not_installed
-    f.follow_installed_alias = true
-    f.build = setup_tab_for_prefix(same_prefix, path: alias_path)
-    stub_formula_loader(new_formula, alias_path)
-    refute_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_follow_alias_and_alias_changed_and_new_target_installed
-    f.follow_installed_alias = true
-    f.build = setup_tab_for_prefix(same_prefix, path: alias_path)
-    stub_formula_loader(new_formula, alias_path)
-    setup_tab_for_prefix(new_formula.prefix) # install new_formula
-    assert_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_no_follow_alias_and_alias_unchanged
-    f.follow_installed_alias = false
-    f.build = setup_tab_for_prefix(same_prefix, path: alias_path)
-    stub_formula_loader(f, alias_path)
-    assert_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_no_follow_alias_and_alias_changed
-    f.follow_installed_alias = false
-    f.build = setup_tab_for_prefix(same_prefix, path: alias_path)
-    stub_formula_loader(formula("foo@2") { url "foo-2.0" }, alias_path)
-    assert_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_old_alias_targets_installed
-    @f = formula(alias_path: alias_path) { url "foo-1.0" }
-    tab = setup_tab_for_prefix(old_alias_target_prefix, path: alias_path)
-    old_formula.build = tab
-    Formula.stubs(:installed).returns([old_formula])
-    refute_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_old_alias_targets_not_installed
-    @f = formula(alias_path: alias_path) { url "foo-1.0" }
-    tab = setup_tab_for_prefix(old_alias_target_prefix, path: old_formula.path)
-    old_formula.build = tab
-    Formula.stubs(:installed).returns([old_formula])
-    assert_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_same_head_installed
-    f.instance_variable_set(:@tap, CoreTap.instance)
-    setup_tab_for_prefix(head_prefix, tap: "homebrew/core")
-    assert_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_different_head_installed
-    f.instance_variable_set(:@tap, CoreTap.instance)
-    setup_tab_for_prefix(head_prefix, tap: "user/repo")
-    assert_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_mixed_taps_greater_version_installed
-    f.instance_variable_set(:@tap, CoreTap.instance)
-    setup_tab_for_prefix(outdated_prefix, tap: "homebrew/core")
-    setup_tab_for_prefix(greater_prefix, tap: "user/repo")
-
-    assert_predicate f.outdated_kegs, :empty?
-
-    setup_tab_for_prefix(greater_prefix, tap: "homebrew/core")
-    reset_outdated_kegs
-
-    assert_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_mixed_taps_outdated_version_installed
-    f.instance_variable_set(:@tap, CoreTap.instance)
-
-    extra_outdated_prefix = HOMEBREW_CELLAR/"#{f.name}/1.0"
-
-    setup_tab_for_prefix(outdated_prefix)
-    setup_tab_for_prefix(extra_outdated_prefix, tap: "homebrew/core")
-    reset_outdated_kegs
-
-    refute_predicate f.outdated_kegs, :empty?
-
-    setup_tab_for_prefix(outdated_prefix, tap: "user/repo")
-    reset_outdated_kegs
-
-    refute_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_same_version_tap_installed
-    f.instance_variable_set(:@tap, CoreTap.instance)
-    setup_tab_for_prefix(same_prefix, tap: "homebrew/core")
-
-    assert_predicate f.outdated_kegs, :empty?
-
-    setup_tab_for_prefix(same_prefix, tap: "user/repo")
-    reset_outdated_kegs
-
-    assert_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_installed_head_less_than_stable
-    tab = setup_tab_for_prefix(head_prefix, versions: { "stable" => "1.0" })
-    refute_predicate f.outdated_kegs, :empty?
-
-    # Tab.for_keg(head_prefix) will be fetched from CACHE but we write it anyway
-    tab.source["versions"] = { "stable" => f.version.to_s }
-    tab.write
-    reset_outdated_kegs
-
-    assert_predicate f.outdated_kegs, :empty?
-  end
-
-  def test_outdated_fetch_head
-    outdated_stable_prefix = HOMEBREW_CELLAR.join("testball/1.0")
-    head_prefix_a = HOMEBREW_CELLAR.join("testball/HEAD")
-    head_prefix_b = HOMEBREW_CELLAR.join("testball/HEAD-aaaaaaa_1")
-    head_prefix_c = HOMEBREW_CELLAR.join("testball/HEAD-5658946")
-
-    setup_tab_for_prefix(outdated_stable_prefix)
-    tab_a = setup_tab_for_prefix(head_prefix_a, versions: { "stable" => "1.0" })
-    setup_tab_for_prefix(head_prefix_b)
-
-    initial_env = ENV.to_hash
-    testball_repo = HOMEBREW_PREFIX.join("testball_repo")
-    testball_repo.mkdir
-
-    @f = formula("testball") do
-      url "foo"
-      version "2.10"
-      head "file://#{testball_repo}", using: :git
-    end
-
-    %w[AUTHOR COMMITTER].each do |role|
-      ENV["GIT_#{role}_NAME"] = "brew tests"
-      ENV["GIT_#{role}_EMAIL"] = "brew-tests@localhost"
-      ENV["GIT_#{role}_DATE"] = "Thu May 21 00:04:11 2009 +0100"
-    end
-
-    testball_repo.cd do
-      FileUtils.touch "LICENSE"
-      shutup do
-        system "git", "init"
-        system "git", "add", "--all"
-        system "git", "commit", "-m", "Initial commit"
-      end
-    end
-
-    refute_predicate f.outdated_kegs(fetch_head: true), :empty?
-
-    tab_a.source["versions"] = { "stable" => f.version.to_s }
-    tab_a.write
-    reset_outdated_kegs
-    refute_predicate f.outdated_kegs(fetch_head: true), :empty?
-
-    head_prefix_a.rmtree
-    reset_outdated_kegs
-    refute_predicate f.outdated_kegs(fetch_head: true), :empty?
-
-    setup_tab_for_prefix(head_prefix_c, source_modified_time: 1)
-    reset_outdated_kegs
-    assert_predicate f.outdated_kegs(fetch_head: true), :empty?
-  ensure
-    ENV.replace(initial_env)
-    testball_repo.rmtree if testball_repo.exist?
-    outdated_stable_prefix.rmtree if outdated_stable_prefix.exist?
-    head_prefix_b.rmtree if head_prefix.exist?
-    head_prefix_c.rmtree if head_prefix_c.exist?
-    FileUtils.rm_rf HOMEBREW_CACHE/"testball--git"
-    FileUtils.rm_rf HOMEBREW_CELLAR/"testball"
-  end
-
-  def test_outdated_kegs_version_scheme_changed
-    @f = formula("testball") do
-      url "foo"
-      version "20141010"
-      version_scheme 1
-    end
-
-    prefix = HOMEBREW_CELLAR.join("testball/0.1")
-    setup_tab_for_prefix(prefix, versions: { "stable" => "0.1" })
-
-    refute_predicate f.outdated_kegs, :empty?
-  ensure
-    prefix.rmtree
-  end
-
-  def test_outdated_kegs_mixed_version_schemes
-    @f = formula("testball") do
-      url "foo"
-      version "20141010"
-      version_scheme 3
-    end
-
-    prefix_a = HOMEBREW_CELLAR.join("testball/20141009")
-    setup_tab_for_prefix(prefix_a, versions: { "stable" => "20141009", "version_scheme" => 1 })
-
-    prefix_b = HOMEBREW_CELLAR.join("testball/2.14")
-    setup_tab_for_prefix(prefix_b, versions: { "stable" => "2.14", "version_scheme" => 2 })
-
-    refute_predicate f.outdated_kegs, :empty?
-    reset_outdated_kegs
-
-    prefix_c = HOMEBREW_CELLAR.join("testball/20141009")
-    setup_tab_for_prefix(prefix_c, versions: { "stable" => "20141009", "version_scheme" => 3 })
-
-    refute_predicate f.outdated_kegs, :empty?
-    reset_outdated_kegs
-
-    prefix_d = HOMEBREW_CELLAR.join("testball/20141011")
-    setup_tab_for_prefix(prefix_d, versions: { "stable" => "20141009", "version_scheme" => 3 })
-    assert_predicate f.outdated_kegs, :empty?
-  ensure
-    f.rack.rmtree
-  end
-
-  def test_outdated_kegs_head_with_version_scheme
-    @f = formula("testball") do
-      url "foo"
-      version "1.0"
-      version_scheme 2
-    end
-
-    head_prefix = HOMEBREW_CELLAR.join("testball/HEAD")
-
-    setup_tab_for_prefix(head_prefix, versions: { "stable" => "1.0", "version_scheme" => 1 })
-    refute_predicate f.outdated_kegs, :empty?
-
-    reset_outdated_kegs
-    head_prefix.rmtree
-
-    setup_tab_for_prefix(head_prefix, versions: { "stable" => "1.0", "version_scheme" => 2 })
-    assert_predicate f.outdated_kegs, :empty?
-  ensure
-    head_prefix.rmtree
-  end
-end
diff --git a/Library/Homebrew/test/formulary_spec.rb b/Library/Homebrew/test/formulary_spec.rb
new file mode 100644
index 000000000..213ad511d
--- /dev/null
+++ b/Library/Homebrew/test/formulary_spec.rb
@@ -0,0 +1,227 @@
+require "formula"
+require "formula_installer"
+require "utils/bottles"
+
+describe Formulary do
+  let(:formula_name) { "testball_bottle" }
+  let(:formula_path) { CoreTap.new.formula_dir/"#{formula_name}.rb" }
+  let(:formula_content) do
+    <<-EOS.undent
+      class #{subject.class_s(formula_name)} < Formula
+        url "file://#{TEST_FIXTURE_DIR}/tarballs/testball-0.1.tbz"
+        sha256 TESTBALL_SHA256
+
+        bottle do
+          cellar :any_skip_relocation
+          root_url "file://#{bottle_dir}"
+          sha256 "9abc8ce779067e26556002c4ca6b9427b9874d25f0cafa7028e05b5c5c410cb4" => :#{Utils::Bottles.tag}
+        end
+
+        def install
+          prefix.install "bin"
+          prefix.install "libexec"
+        end
+      end
+    EOS
+  end
+  let(:bottle_dir) { Pathname.new("#{TEST_FIXTURE_DIR}/bottles") }
+  let(:bottle) { bottle_dir/"testball_bottle-0.1.#{Utils::Bottles.tag}.bottle.tar.gz" }
+
+  describe "::class_s" do
+    it "replaces '+' with 'x'" do
+      expect(subject.class_s("foo++")).to eq("Fooxx")
+    end
+
+    it "converts a string to PascalCase" do
+      expect(subject.class_s("shell.fm")).to eq("ShellFm")
+      expect(subject.class_s("s-lang")).to eq("SLang")
+      expect(subject.class_s("pkg-config")).to eq("PkgConfig")
+      expect(subject.class_s("foo_bar")).to eq("FooBar")
+    end
+
+    it "replaces '@' with 'AT'" do
+      expect(subject.class_s("openssl@1.1")).to eq("OpensslAT11")
+    end
+  end
+
+  describe "::factory" do
+    before(:each) do
+      formula_path.write formula_content
+    end
+
+    it "returns a Formula" do
+      expect(subject.factory(formula_name)).to be_kind_of(Formula)
+    end
+
+    it "returns a Formula when given a fully qualified name" do
+      expect(subject.factory("homebrew/core/#{formula_name}")).to be_kind_of(Formula)
+    end
+
+    it "raises an error if the Formula cannot be found" do
+      expect {
+        subject.factory("not_existed_formula")
+      }.to raise_error(FormulaUnavailableError)
+    end
+
+    context "if the Formula has the wrong class" do
+      let(:formula_name) { "giraffe" }
+      let(:formula_content) do
+        <<-EOS.undent
+          class Wrong#{subject.class_s(formula_name)} < Formula
+          end
+        EOS
+      end
+
+      it "raises an error" do
+        expect {
+          subject.factory(formula_name)
+        }.to raise_error(FormulaClassUnavailableError)
+      end
+    end
+
+    it "returns a Formula when given a path" do
+      expect(subject.factory(formula_path)).to be_kind_of(Formula)
+    end
+
+    it "returns a Formula when given a URL" do
+      formula = shutup do
+        subject.factory("file://#{formula_path}")
+      end
+
+      expect(formula).to be_kind_of(Formula)
+    end
+
+    it "returns a Formula when given a bottle" do
+      formula = subject.factory(bottle)
+      expect(formula).to be_kind_of(Formula)
+      expect(formula.local_bottle_path).to eq(bottle.realpath)
+    end
+
+    it "returns a Formula when given an alias" do
+      alias_dir = CoreTap.instance.alias_dir
+      alias_dir.mkpath
+      alias_path = alias_dir/"foo"
+      FileUtils.ln_s formula_path, alias_path
+      result = subject.factory("foo")
+      expect(result).to be_kind_of(Formula)
+      expect(result.alias_path).to eq(alias_path.to_s)
+    end
+
+    context "with installed Formula" do
+      let(:formula) { subject.factory(formula_path) }
+      let(:installer) { FormulaInstaller.new(formula) }
+
+      it "returns a Formula when given a rack" do
+        shutup do
+          installer.install
+        end
+
+        f = subject.from_rack(formula.rack)
+        expect(f).to be_kind_of(Formula)
+        expect(f.build).to be_kind_of(Tab)
+      end
+
+      it "returns a Formula when given a Keg" do
+        shutup do
+          installer.install
+        end
+
+        keg = Keg.new(formula.prefix)
+        f = subject.from_keg(keg)
+        expect(f).to be_kind_of(Formula)
+        expect(f.build).to be_kind_of(Tab)
+      end
+    end
+
+    context "from Tap" do
+      let(:tap) { Tap.new("homebrew", "foo") }
+      let(:formula_path) { tap.path/"#{formula_name}.rb" }
+
+      it "returns a Formula when given a name" do
+        expect(subject.factory(formula_name)).to be_kind_of(Formula)
+      end
+
+      it "returns a Formula from an Alias path" do
+        alias_dir = tap.path/"Aliases"
+        alias_dir.mkpath
+        FileUtils.ln_s formula_path, alias_dir/"bar"
+        expect(subject.factory("bar")).to be_kind_of(Formula)
+      end
+
+      it "raises an error when the Formula cannot be found" do
+        expect {
+          subject.factory("#{tap}/not_existed_formula")
+        }.to raise_error(TapFormulaUnavailableError)
+      end
+
+      it "returns a Formula when given a fully qualified name" do
+        expect(subject.factory("#{tap}/#{formula_name}")).to be_kind_of(Formula)
+      end
+
+      it "raises an error if a Formula is in multiple Taps" do
+        begin
+          another_tap = Tap.new("homebrew", "bar")
+          (another_tap.path/"#{formula_name}.rb").write formula_content
+          expect {
+            subject.factory(formula_name)
+          }.to raise_error(TapFormulaAmbiguityError)
+        ensure
+          another_tap.path.rmtree
+        end
+      end
+    end
+  end
+
+  specify "::from_contents" do
+    expect(subject.from_contents(formula_name, formula_path, formula_content)).to be_kind_of(Formula)
+  end
+
+  specify "::to_rack" do
+    expect(subject.to_rack(formula_name)).to eq(HOMEBREW_CELLAR/formula_name)
+
+    (HOMEBREW_CELLAR/formula_name).mkpath
+    expect(subject.to_rack(formula_name)).to eq(HOMEBREW_CELLAR/formula_name)
+
+    expect {
+      subject.to_rack("a/b/#{formula_name}")
+    }.to raise_error(TapFormulaUnavailableError)
+  end
+
+  describe "::find_with_priority" do
+    let(:core_path) { CoreTap.new.formula_dir/"#{formula_name}.rb" }
+    let(:tap) { Tap.new("homebrew", "foo") }
+    let(:tap_path) { tap.path/"#{formula_name}.rb" }
+
+    before(:each) do
+      core_path.write formula_content
+      tap_path.write formula_content
+    end
+
+    it "prioritizes core Formulae" do
+      formula = subject.find_with_priority(formula_name)
+      expect(formula).to be_kind_of(Formula)
+      expect(formula.path).to eq(core_path)
+    end
+
+    it "prioritizes Formulae from pinned Taps" do
+      begin
+        tap.pin
+        formula = shutup do
+          subject.find_with_priority(formula_name)
+        end
+        expect(formula).to be_kind_of(Formula)
+        expect(formula.path).to eq(tap_path.realpath)
+      ensure
+        tap.pinned_symlink_path.parent.parent.rmtree
+      end
+    end
+  end
+
+  describe "::core_path" do
+    it "returns the path to a Formula in the core tap" do
+      name = "foo-bar"
+      expect(subject.core_path(name))
+        .to eq(Pathname.new("#{HOMEBREW_LIBRARY}/Taps/homebrew/homebrew-core/Formula/#{name}.rb"))
+    end
+  end
+end
diff --git a/Library/Homebrew/test/formulary_test.rb b/Library/Homebrew/test/formulary_test.rb
deleted file mode 100644
index 3d88c8407..000000000
--- a/Library/Homebrew/test/formulary_test.rb
+++ /dev/null
@@ -1,208 +0,0 @@
-require "testing_env"
-require "formula"
-require "formula_installer"
-require "utils/bottles"
-
-class FormularyTest < Homebrew::TestCase
-  def test_class_naming
-    assert_equal "ShellFm", Formulary.class_s("shell.fm")
-    assert_equal "Fooxx", Formulary.class_s("foo++")
-    assert_equal "SLang", Formulary.class_s("s-lang")
-    assert_equal "PkgConfig", Formulary.class_s("pkg-config")
-    assert_equal "FooBar", Formulary.class_s("foo_bar")
-    assert_equal "OpensslAT11", Formulary.class_s("openssl@1.1")
-  end
-end
-
-class FormularyFactoryTest < Homebrew::TestCase
-  def setup
-    @name = "testball_bottle"
-    @path = CoreTap.new.formula_dir/"#{@name}.rb"
-    @bottle_dir = Pathname.new("#{TEST_FIXTURE_DIR}/bottles")
-    @bottle = @bottle_dir/"testball_bottle-0.1.#{Utils::Bottles.tag}.bottle.tar.gz"
-    @path.write <<-EOS.undent
-      class #{Formulary.class_s(@name)} < Formula
-        url "file://#{TEST_FIXTURE_DIR}/tarballs/testball-0.1.tbz"
-        sha256 TESTBALL_SHA256
-
-        bottle do
-          cellar :any_skip_relocation
-          root_url "file://#{@bottle_dir}"
-          sha256 "9abc8ce779067e26556002c4ca6b9427b9874d25f0cafa7028e05b5c5c410cb4" => :#{Utils::Bottles.tag}
-        end
-
-        def install
-          prefix.install "bin"
-          prefix.install "libexec"
-        end
-      end
-    EOS
-  end
-
-  def teardown
-    @path.unlink
-  end
-
-  def test_factory
-    assert_kind_of Formula, Formulary.factory(@name)
-  end
-
-  def test_factory_with_fully_qualified_name
-    assert_kind_of Formula, Formulary.factory("homebrew/core/#{@name}")
-  end
-
-  def test_formula_unavailable_error
-    assert_raises(FormulaUnavailableError) { Formulary.factory("not_existed_formula") }
-  end
-
-  def test_formula_class_unavailable_error
-    name = "giraffe"
-    path = CoreTap.new.formula_dir/"#{name}.rb"
-    path.write "class Wrong#{Formulary.class_s(name)} < Formula\nend\n"
-
-    assert_raises(FormulaClassUnavailableError) { Formulary.factory(name) }
-  ensure
-    path.unlink
-  end
-
-  def test_factory_from_path
-    assert_kind_of Formula, Formulary.factory(@path)
-  end
-
-  def test_factory_from_url
-    formula = shutup { Formulary.factory("file://#{@path}") }
-    assert_kind_of Formula, formula
-  ensure
-    formula.path.unlink
-  end
-
-  def test_factory_from_bottle
-    formula = Formulary.factory(@bottle)
-    assert_kind_of Formula, formula
-    assert_equal @bottle.realpath, formula.local_bottle_path
-  end
-
-  def test_factory_from_alias
-    alias_dir = CoreTap.instance.alias_dir
-    alias_dir.mkpath
-    alias_path = alias_dir/"foo"
-    FileUtils.ln_s @path, alias_path
-    result = Formulary.factory("foo")
-    assert_kind_of Formula, result
-    assert_equal alias_path.to_s, result.alias_path
-  ensure
-    alias_dir.rmtree
-  end
-
-  def test_factory_from_rack_and_from_keg
-    formula = Formulary.factory(@path)
-    installer = FormulaInstaller.new(formula)
-    shutup { installer.install }
-    keg = Keg.new(formula.prefix)
-    f = Formulary.from_rack(formula.rack)
-    assert_kind_of Formula, f
-    assert_kind_of Tab, f.build
-    f = Formulary.from_keg(keg)
-    assert_kind_of Formula, f
-    assert_kind_of Tab, f.build
-  ensure
-    keg.unlink
-    keg.uninstall
-    formula.clear_cache
-    formula.bottle.clear_cache
-  end
-
-  def test_load_from_contents
-    assert_kind_of Formula, Formulary.from_contents(@name, @path, @path.read)
-  end
-
-  def test_to_rack
-    assert_equal HOMEBREW_CELLAR/@name, Formulary.to_rack(@name)
-    (HOMEBREW_CELLAR/@name).mkpath
-    assert_equal HOMEBREW_CELLAR/@name, Formulary.to_rack(@name)
-    assert_raises(TapFormulaUnavailableError) { Formulary.to_rack("a/b/#{@name}") }
-  ensure
-    FileUtils.rm_rf HOMEBREW_CELLAR/@name
-  end
-end
-
-class FormularyTapFactoryTest < Homebrew::TestCase
-  def setup
-    @name = "foo"
-    @tap = Tap.new "homebrew", "foo"
-    @path = @tap.path/"#{@name}.rb"
-    @code = <<-EOS.undent
-      class #{Formulary.class_s(@name)} < Formula
-        url "foo-1.0"
-      end
-    EOS
-    @path.write @code
-  end
-
-  def teardown
-    @tap.path.rmtree
-  end
-
-  def test_factory_tap_formula
-    assert_kind_of Formula, Formulary.factory(@name)
-  end
-
-  def test_factory_tap_alias
-    alias_dir = @tap.path/"Aliases"
-    alias_dir.mkpath
-    FileUtils.ln_s @path, alias_dir/"bar"
-    assert_kind_of Formula, Formulary.factory("bar")
-  end
-
-  def test_tap_formula_unavailable_error
-    assert_raises(TapFormulaUnavailableError) { Formulary.factory("#{@tap}/not_existed_formula") }
-  end
-
-  def test_factory_tap_formula_with_fully_qualified_name
-    assert_kind_of Formula, Formulary.factory("#{@tap}/#{@name}")
-  end
-
-  def test_factory_ambiguity_tap_formulae
-    another_tap = Tap.new "homebrew", "bar"
-    (another_tap.path/"#{@name}.rb").write @code
-    assert_raises(TapFormulaAmbiguityError) { Formulary.factory(@name) }
-  ensure
-    another_tap.path.rmtree
-  end
-end
-
-class FormularyTapPriorityTest < Homebrew::TestCase
-  def setup
-    @name = "foo"
-    @core_path = CoreTap.new.formula_dir/"#{@name}.rb"
-    @tap = Tap.new "homebrew", "foo"
-    @tap_path = @tap.path/"#{@name}.rb"
-    code = <<-EOS.undent
-      class #{Formulary.class_s(@name)} < Formula
-        url "foo-1.0"
-      end
-    EOS
-    @core_path.write code
-    @tap_path.write code
-  end
-
-  def teardown
-    @core_path.unlink
-    @tap.path.rmtree
-  end
-
-  def test_find_with_priority_core_formula
-    formula = Formulary.find_with_priority(@name)
-    assert_kind_of Formula, formula
-    assert_equal @core_path, formula.path
-  end
-
-  def test_find_with_priority_tap_formula
-    @tap.pin
-    formula = shutup { Formulary.find_with_priority(@name) }
-    assert_kind_of Formula, formula
-    assert_equal @tap_path.realpath, formula.path
-  ensure
-    @tap.pinned_symlink_path.parent.parent.rmtree
-  end
-end
diff --git a/Library/Homebrew/test/gpg2_requirement_spec.rb b/Library/Homebrew/test/gpg2_requirement_spec.rb
new file mode 100644
index 000000000..f46b31196
--- /dev/null
+++ b/Library/Homebrew/test/gpg2_requirement_spec.rb
@@ -0,0 +1,23 @@
+require "requirements/gpg2_requirement"
+require "fileutils"
+
+describe GPG2Requirement do
+  let(:dir) { @dir = Pathname.new(Dir.mktmpdir) }
+
+  after(:each) do
+    FileUtils.rm_rf dir unless @dir.nil?
+  end
+
+  describe "#satisfied?" do
+    it "returns true if GPG2 is installed" do
+      ENV["PATH"] = dir/"bin"
+      (dir/"bin/gpg").write <<-EOS.undent
+        #!/bin/bash
+        echo 2.0.30
+      EOS
+      FileUtils.chmod 0755, dir/"bin/gpg"
+
+      expect(subject).to be_satisfied
+    end
+  end
+end
diff --git a/Library/Homebrew/test/gpg2_requirement_test.rb b/Library/Homebrew/test/gpg2_requirement_test.rb
deleted file mode 100644
index fa7fc9ea4..000000000
--- a/Library/Homebrew/test/gpg2_requirement_test.rb
+++ /dev/null
@@ -1,24 +0,0 @@
-require "testing_env"
-require "requirements/gpg2_requirement"
-require "fileutils"
-
-class GPG2RequirementTests < Homebrew::TestCase
-  def setup
-    @dir = Pathname.new(mktmpdir)
-    (@dir/"bin/gpg").write <<-EOS.undent
-      #!/bin/bash
-      echo 2.0.30
-    EOS
-    FileUtils.chmod 0755, @dir/"bin/gpg"
-  end
-
-  def teardown
-    FileUtils.rm_rf @dir
-  end
-
-  def test_satisfied
-    with_environment("PATH" => @dir/"bin") do
-      assert_predicate GPG2Requirement.new, :satisfied?
-    end
-  end
-end
diff --git a/Library/Homebrew/test/gpg_spec.rb b/Library/Homebrew/test/gpg_spec.rb
new file mode 100644
index 000000000..9809dccb5
--- /dev/null
+++ b/Library/Homebrew/test/gpg_spec.rb
@@ -0,0 +1,21 @@
+require "gpg"
+
+describe Gpg do
+  subject { described_class }
+
+  describe "::create_test_key" do
+    it "creates a test key in the home directory" do
+      skip "GPG Unavailable" unless subject.available?
+
+      Dir.mktmpdir do |dir|
+        ENV["HOME"] = dir
+        dir = Pathname.new(dir)
+
+        shutup do
+          subject.create_test_key(dir)
+        end
+        expect(dir/".gnupg/secring.gpg").to exist
+      end
+    end
+  end
+end
diff --git a/Library/Homebrew/test/gpg_test.rb b/Library/Homebrew/test/gpg_test.rb
deleted file mode 100644
index 0374bdab4..000000000
--- a/Library/Homebrew/test/gpg_test.rb
+++ /dev/null
@@ -1,20 +0,0 @@
-require "testing_env"
-require "gpg"
-
-class GpgTest < Homebrew::TestCase
-  def setup
-    skip "GPG Unavailable" unless Gpg.available?
-    @dir = Pathname.new(mktmpdir)
-  end
-
-  def test_create_test_key
-    Dir.chdir(@dir) do
-      with_environment("HOME" => @dir) do
-        shutup { Gpg.create_test_key(@dir) }
-        assert_predicate @dir/".gnupg/secring.gpg", :exist?
-      end
-    end
-  ensure
-    @dir.rmtree
-  end
-end
diff --git a/Library/Homebrew/test/hardware_spec.rb b/Library/Homebrew/test/hardware_spec.rb
new file mode 100644
index 000000000..c5f8daf4e
--- /dev/null
+++ b/Library/Homebrew/test/hardware_spec.rb
@@ -0,0 +1,40 @@
+require "hardware"
+
+module Hardware
+  describe CPU do
+    describe "::type" do
+      it "returns the current CPU's type as a symbol, or :dunno if it cannot be detected" do
+        expect(
+          [
+            :intel,
+            :ppc,
+            :dunno,
+          ],
+        ).to include(described_class.type)
+      end
+    end
+
+    describe "::family" do
+      it "returns the current CPU's family name as a symbol, or :dunno if it cannot be detected" do
+        skip "Needs an Intel CPU." unless described_class.intel?
+
+        expect(
+          [
+            :core,
+            :core2,
+            :penryn,
+            :nehalem,
+            :arrandale,
+            :sandybridge,
+            :ivybridge,
+            :haswell,
+            :broadwell,
+            :skylake,
+            :kabylake,
+            :dunno,
+          ],
+        ).to include(described_class.family)
+      end
+    end
+  end
+end
diff --git a/Library/Homebrew/test/hardware_test.rb b/Library/Homebrew/test/hardware_test.rb
deleted file mode 100644
index 69f881a60..000000000
--- a/Library/Homebrew/test/hardware_test.rb
+++ /dev/null
@@ -1,15 +0,0 @@
-require "testing_env"
-require "hardware"
-
-class HardwareTests < Homebrew::TestCase
-  def test_hardware_cpu_type
-    assert_includes [:intel, :ppc, :dunno], Hardware::CPU.type
-  end
-
-  if Hardware::CPU.intel?
-    def test_hardware_intel_family
-      families = [:core, :core2, :penryn, :nehalem, :arrandale, :sandybridge, :ivybridge, :haswell, :broadwell, :skylake, :kabylake, :dunno]
-      assert_includes families, Hardware::CPU.family
-    end
-  end
-end
diff --git a/Library/Homebrew/test/help_test.rb b/Library/Homebrew/test/help_test.rb
deleted file mode 100644
index 92dd99721..000000000
--- a/Library/Homebrew/test/help_test.rb
+++ /dev/null
@@ -1,21 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestHelp < IntegrationCommandTestCase
-  def test_help
-    assert_match "Example usage:\n",
-                 cmd_fail # Generic help (empty argument list).
-    assert_match "Unknown command: command-that-does-not-exist",
-                 cmd_fail("help", "command-that-does-not-exist")
-    assert_match(/^brew cat /,
-                 cmd_fail("cat")) # Missing formula argument triggers help.
-
-    assert_match "Example usage:\n",
-                 cmd("help") # Generic help.
-    assert_match(/^brew cat /,
-                 cmd("help", "cat")) # Internal command (documented, Ruby).
-    assert_match(/^brew update /,
-                 cmd("help", "update")) # Internal command (documented, Shell).
-    assert_match(/^brew update-test /,
-                 cmd("help", "update-test")) # Internal developer command (documented, Ruby).
-  end
-end
diff --git a/Library/Homebrew/test/home_test.rb b/Library/Homebrew/test/home_test.rb
deleted file mode 100644
index ff06b72c1..000000000
--- a/Library/Homebrew/test/home_test.rb
+++ /dev/null
@@ -1,12 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestHome < IntegrationCommandTestCase
-  def test_home
-    setup_test_formula "testball"
-
-    assert_equal HOMEBREW_WWW,
-                 cmd("home", "HOMEBREW_BROWSER" => "echo")
-    assert_equal Formula["testball"].homepage,
-                 cmd("home", "testball", "HOMEBREW_BROWSER" => "echo")
-  end
-end
diff --git a/Library/Homebrew/test/info_test.rb b/Library/Homebrew/test/info_test.rb
deleted file mode 100644
index f71044bf0..000000000
--- a/Library/Homebrew/test/info_test.rb
+++ /dev/null
@@ -1,29 +0,0 @@
-require "testing_env"
-require "cmd/info"
-require "formula"
-require "testing_env"
-
-class IntegrationCommandTestInfo < IntegrationCommandTestCase
-  def test_info
-    setup_test_formula "testball"
-
-    assert_match "testball: stable 0.1",
-                 cmd("info", "testball")
-  end
-end
-
-class InfoCommandTests < Homebrew::TestCase
-  def test_github_remote_path
-    remote = "https://github.com/Homebrew/homebrew-core"
-    assert_equal "https://github.com/Homebrew/homebrew-core/blob/master/Formula/git.rb",
-      Homebrew.github_remote_path(remote, "Formula/git.rb")
-    assert_equal "https://github.com/Homebrew/homebrew-core/blob/master/Formula/git.rb",
-      Homebrew.github_remote_path("#{remote}.git", "Formula/git.rb")
-
-    assert_equal "https://github.com/user/repo/blob/master/foo.rb",
-      Homebrew.github_remote_path("git@github.com:user/repo", "foo.rb")
-
-    assert_equal "https://mywebsite.com/foo/bar.rb",
-      Homebrew.github_remote_path("https://mywebsite.com", "foo/bar.rb")
-  end
-end
diff --git a/Library/Homebrew/test/inreplace_spec.rb b/Library/Homebrew/test/inreplace_spec.rb
new file mode 100644
index 000000000..5be44f50d
--- /dev/null
+++ b/Library/Homebrew/test/inreplace_spec.rb
@@ -0,0 +1,251 @@
+require "extend/string"
+require "tempfile"
+require "utils/inreplace"
+
+describe StringInreplaceExtension do
+  subject { string.extend(described_class) }
+
+  describe "#change_make_var!" do
+    context "flag" do
+      context "with spaces" do
+        let(:string) do
+          <<-EOS.undent
+            OTHER=def
+            FLAG = abc
+            FLAG2=abc
+          EOS
+        end
+
+        it "is successfully replaced" do
+          subject.change_make_var! "FLAG", "def"
+          expect(subject).to eq <<-EOS.undent
+            OTHER=def
+            FLAG=def
+            FLAG2=abc
+          EOS
+        end
+
+        it "is successfully appended" do
+          subject.change_make_var! "FLAG", "\\1 def"
+          expect(subject).to eq <<-EOS.undent
+            OTHER=def
+            FLAG=abc def
+            FLAG2=abc
+          EOS
+        end
+      end
+
+      context "with tabs" do
+        let(:string) do
+          <<-EOS.undent
+            CFLAGS\t=\t-Wall -O2
+            LDFLAGS\t=\t-lcrypto -lssl
+          EOS
+        end
+
+        it "is successfully replaced" do
+          subject.change_make_var! "CFLAGS", "-O3"
+          expect(subject).to eq <<-EOS.undent
+            CFLAGS=-O3
+            LDFLAGS\t=\t-lcrypto -lssl
+          EOS
+        end
+      end
+    end
+
+    context "empty flag between other flags" do
+      let(:string) do
+        <<-EOS.undent
+          OTHER=def
+          FLAG =
+          FLAG2=abc
+        EOS
+      end
+
+      it "is successfully replaced" do
+        subject.change_make_var! "FLAG", "def"
+        expect(subject).to eq <<-EOS.undent
+          OTHER=def
+          FLAG=def
+          FLAG2=abc
+        EOS
+      end
+    end
+
+    context "empty flag" do
+      let(:string) do
+        <<-EOS.undent
+          FLAG =
+          mv file_a file_b
+        EOS
+      end
+
+      it "is successfully replaced" do
+        subject.change_make_var! "FLAG", "def"
+        expect(subject).to eq <<-EOS.undent
+          FLAG=def
+          mv file_a file_b
+        EOS
+      end
+    end
+
+    context "shell-style variable" do
+      let(:string) do
+        <<-EOS.undent
+          OTHER=def
+          FLAG=abc
+          FLAG2=abc
+        EOS
+      end
+
+      it "is successfully replaced" do
+        subject.change_make_var! "FLAG", "def"
+        expect(subject).to eq <<-EOS.undent
+          OTHER=def
+          FLAG=def
+          FLAG2=abc
+        EOS
+      end
+    end
+  end
+
+  describe "#remove_make_var!" do
+    context "flag" do
+      context "with spaces" do
+        let(:string) do
+          <<-EOS.undent
+            OTHER=def
+            FLAG = abc
+            FLAG2 = def
+          EOS
+        end
+
+        it "is successfully removed" do
+          subject.remove_make_var! "FLAG"
+          expect(subject).to eq <<-EOS.undent
+            OTHER=def
+            FLAG2 = def
+          EOS
+        end
+      end
+
+      context "with tabs" do
+        let(:string) do
+          <<-EOS.undent
+            CFLAGS\t=\t-Wall -O2
+            LDFLAGS\t=\t-lcrypto -lssl
+          EOS
+        end
+
+        it "is successfully removed" do
+          subject.remove_make_var! "LDFLAGS"
+          expect(subject).to eq <<-EOS.undent
+            CFLAGS\t=\t-Wall -O2
+          EOS
+        end
+      end
+    end
+
+    context "multiple flags" do
+      let(:string) do
+        <<-EOS.undent
+          OTHER=def
+          FLAG = abc
+          FLAG2 = def
+          OTHER2=def
+        EOS
+      end
+
+      specify "are be successfully removed" do
+        subject.remove_make_var! ["FLAG", "FLAG2"]
+        expect(subject).to eq <<-EOS.undent
+          OTHER=def
+          OTHER2=def
+        EOS
+      end
+    end
+  end
+
+  describe "#get_make_var" do
+    context "with spaces" do
+      let(:string) do
+        <<-EOS.undent
+          CFLAGS = -Wall -O2
+          LDFLAGS = -lcrypto -lssl
+        EOS
+      end
+
+      it "extracts the value for a given variable" do
+        expect(subject.get_make_var("CFLAGS")).to eq("-Wall -O2")
+      end
+    end
+
+    context "with tabs" do
+      let(:string) do
+        <<-EOS.undent
+          CFLAGS\t=\t-Wall -O2
+          LDFLAGS\t=\t-lcrypto -lssl
+        EOS
+      end
+
+      it "extracts the value for a given variable" do
+        expect(subject.get_make_var("CFLAGS")).to eq("-Wall -O2")
+      end
+    end
+  end
+
+  describe "#sub!" do
+    let(:string) { "foo" }
+
+    it "replaces the first occurence" do
+      subject.sub!("o", "e")
+      expect(subject).to eq("feo")
+    end
+  end
+
+  describe "#gsub!" do
+    let(:string) { "foo" }
+
+    it "replaces the all occurences" do
+      subject.gsub!("o", "e") # rubocop:disable Performance/StringReplacement
+      expect(subject).to eq("fee")
+    end
+  end
+end
+
+describe Utils::Inreplace do
+  let(:file) { Tempfile.new("test") }
+
+  before(:each) do
+    file.write <<-EOS.undent
+      a
+      b
+      c
+    EOS
+  end
+
+  after(:each) { file.unlink }
+
+  it "raises error if there is nothing to replace" do
+    expect {
+      described_class.inreplace file.path, "d", "f"
+    }.to raise_error(Utils::InreplaceError)
+  end
+
+  it "raises error if there is nothing to replace" do
+    expect {
+      described_class.inreplace(file.path) do |s|
+        s.gsub!("d", "f") # rubocop:disable Performance/StringReplacement
+      end
+    }.to raise_error(Utils::InreplaceError)
+  end
+
+  it "raises error if there is nothing to replace" do
+    expect {
+      described_class.inreplace(file.path) do |s|
+        s.change_make_var! "VAR", "value"
+        s.remove_make_var! "VAR2"
+      end
+    }.to raise_error(Utils::InreplaceError)
+  end
+end
diff --git a/Library/Homebrew/test/inreplace_test.rb b/Library/Homebrew/test/inreplace_test.rb
deleted file mode 100644
index 0e62f9d3f..000000000
--- a/Library/Homebrew/test/inreplace_test.rb
+++ /dev/null
@@ -1,119 +0,0 @@
-require "testing_env"
-require "extend/string"
-require "utils/inreplace"
-
-class InreplaceTest < Homebrew::TestCase
-  def test_change_make_var
-    # Replace flag
-    s1 = "OTHER=def\nFLAG = abc\nFLAG2=abc"
-    s1.extend(StringInreplaceExtension)
-    s1.change_make_var! "FLAG", "def"
-    assert_equal "OTHER=def\nFLAG=def\nFLAG2=abc", s1
-  end
-
-  def test_change_make_var_empty
-    # Replace empty flag
-    s1 = "OTHER=def\nFLAG = \nFLAG2=abc"
-    s1.extend(StringInreplaceExtension)
-    s1.change_make_var! "FLAG", "def"
-    assert_equal "OTHER=def\nFLAG=def\nFLAG2=abc", s1
-  end
-
-  def test_change_make_var_empty_2
-    # Replace empty flag
-    s1 = "FLAG = \nmv file_a file_b"
-    s1.extend(StringInreplaceExtension)
-    s1.change_make_var! "FLAG", "def"
-    assert_equal "FLAG=def\nmv file_a file_b", s1
-  end
-
-  def test_change_make_var_append
-    # Append to flag
-    s1 = "OTHER=def\nFLAG = abc\nFLAG2=abc"
-    s1.extend(StringInreplaceExtension)
-    s1.change_make_var! "FLAG", "\\1 def"
-    assert_equal "OTHER=def\nFLAG=abc def\nFLAG2=abc", s1
-  end
-
-  def test_change_make_var_shell_style
-    # Shell variables have no spaces around =
-    s1 = "OTHER=def\nFLAG=abc\nFLAG2=abc"
-    s1.extend(StringInreplaceExtension)
-    s1.change_make_var! "FLAG", "def"
-    assert_equal "OTHER=def\nFLAG=def\nFLAG2=abc", s1
-  end
-
-  def test_remove_make_var
-    # Replace flag
-    s1 = "OTHER=def\nFLAG = abc\nFLAG2 = def"
-    s1.extend(StringInreplaceExtension)
-    s1.remove_make_var! "FLAG"
-    assert_equal "OTHER=def\nFLAG2 = def", s1
-  end
-
-  def test_remove_make_vars
-    # Replace flag
-    s1 = "OTHER=def\nFLAG = abc\nFLAG2 = def\nOTHER2=def"
-    s1.extend(StringInreplaceExtension)
-    s1.remove_make_var! ["FLAG", "FLAG2"]
-    assert_equal "OTHER=def\nOTHER2=def", s1
-  end
-
-  def test_get_make_var
-    s = "CFLAGS = -Wall -O2\nLDFLAGS = -lcrypto -lssl"
-    s.extend(StringInreplaceExtension)
-    assert_equal "-Wall -O2", s.get_make_var("CFLAGS")
-  end
-
-  def test_change_make_var_with_tabs
-    s = "CFLAGS\t=\t-Wall -O2\nLDFLAGS\t=\t-lcrypto -lssl"
-    s.extend(StringInreplaceExtension)
-
-    assert_equal "-Wall -O2", s.get_make_var("CFLAGS")
-
-    s.change_make_var! "CFLAGS", "-O3"
-    assert_equal "CFLAGS=-O3\nLDFLAGS\t=\t-lcrypto -lssl", s
-
-    s.remove_make_var! "LDFLAGS"
-    assert_equal "CFLAGS=-O3\n", s
-  end
-
-  def test_sub_gsub
-    s = "foo"
-    s.extend(StringInreplaceExtension)
-
-    s.sub!("f", "b")
-    assert_equal "boo", s
-
-    # Under current context, we are testing `String#gsub!`, so let's disable rubocop temporarily.
-    s.gsub!("o", "e") # rubocop:disable Performance/StringReplacement
-    assert_equal "bee", s
-  end
-
-  def test_inreplace_errors
-    require "tempfile"
-    extend(Utils::Inreplace)
-
-    file = Tempfile.new("test")
-
-    file.write "a\nb\nc\n"
-
-    assert_raises(Utils::InreplaceError) do
-      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(file.path) { |s| s.gsub!("d", "f") } # rubocop:disable Performance/StringReplacement
-    end
-
-    assert_raises(Utils::InreplaceError) do
-      inreplace(file.path) do |s|
-        s.change_make_var! "VAR", "value"
-        s.remove_make_var! "VAR2"
-      end
-    end
-  ensure
-    file.unlink
-  end
-end
diff --git a/Library/Homebrew/test/install_test.rb b/Library/Homebrew/test/install_test.rb
deleted file mode 100644
index e047c0030..000000000
--- a/Library/Homebrew/test/install_test.rb
+++ /dev/null
@@ -1,147 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestInstall < IntegrationCommandTestCase
-  def test_install
-    setup_test_formula "testball1"
-    assert_match "Specify `--HEAD`", cmd_fail("install", "testball1", "--head")
-    assert_match "No head is defined", cmd_fail("install", "testball1", "--HEAD")
-    assert_match "No devel block", cmd_fail("install", "testball1", "--devel")
-    assert_match "#{HOMEBREW_CELLAR}/testball1/0.1", cmd("install", "testball1")
-    assert_match "testball1-0.1 already installed", cmd("install", "testball1")
-    assert_match "MacRuby is not packaged", cmd_fail("install", "macruby")
-    assert_match "No available formula", cmd_fail("install", "formula")
-    assert_match "This similarly named formula was found",
-      cmd_fail("install", "testball")
-
-    setup_test_formula "testball2"
-    assert_match "These similarly named formulae were found",
-      cmd_fail("install", "testball")
-
-    install_and_rename_coretap_formula "testball1", "testball2"
-    assert_match "testball1 already installed, it's just not migrated",
-      cmd("install", "testball2")
-  end
-
-  def test_install_failures
-    path = setup_test_formula "testball1", "version \"1.0\""
-    devel_content = <<-EOS.undent
-      version "3.0"
-      devel do
-        url "#{Formulary.factory("testball1").stable.url}"
-        sha256 "#{TESTBALL_SHA256}"
-        version "2.0"
-      end
-    EOS
-
-    assert_match "#{HOMEBREW_CELLAR}/testball1/1.0", cmd("install", "testball1")
-
-    FileUtils.rm path
-    setup_test_formula "testball1", devel_content
-
-    assert_match "first `brew unlink testball1`", cmd_fail("install", "testball1")
-    assert_match "#{HOMEBREW_CELLAR}/testball1/1.0", cmd("unlink", "testball1")
-    assert_match "#{HOMEBREW_CELLAR}/testball1/2.0", cmd("install", "testball1", "--devel")
-    assert_match "#{HOMEBREW_CELLAR}/testball1/2.0", cmd("unlink", "testball1")
-    assert_match "#{HOMEBREW_CELLAR}/testball1/3.0", cmd("install", "testball1")
-
-    cmd("switch", "testball1", "2.0")
-    assert_match "already installed, however linked version is",
-      cmd("install", "testball1")
-    assert_match "#{HOMEBREW_CELLAR}/testball1/2.0", cmd("unlink", "testball1")
-    assert_match "just not linked", cmd("install", "testball1")
-  end
-
-  def test_install_keg_only_outdated
-    path_keg_only = setup_test_formula "testball1", <<-EOS.undent
-    version "1.0"
-    keg_only "test reason"
-    EOS
-
-    assert_match "#{HOMEBREW_CELLAR}/testball1/1.0", cmd("install", "testball1")
-
-    FileUtils.rm path_keg_only
-    setup_test_formula "testball1", <<-EOS.undent
-      version "2.0"
-      keg_only "test reason"
-    EOS
-
-    assert_match "keg-only and another version is linked to opt",
-      cmd("install", "testball1")
-
-    assert_match "#{HOMEBREW_CELLAR}/testball1/2.0",
-      cmd("install", "testball1", "--force")
-  end
-
-  def test_install_head_installed
-    initial_env = ENV.to_hash
-    %w[AUTHOR COMMITTER].each do |role|
-      ENV["GIT_#{role}_NAME"] = "brew tests"
-      ENV["GIT_#{role}_EMAIL"] = "brew-tests@localhost"
-      ENV["GIT_#{role}_DATE"] = "Thu May 21 00:04:11 2009 +0100"
-    end
-
-    repo_path = HOMEBREW_CACHE.join("repo")
-    repo_path.join("bin").mkpath
-
-    repo_path.cd do
-      shutup do
-        system "git", "init"
-        system "git", "remote", "add", "origin", "https://github.com/Homebrew/homebrew-foo"
-        FileUtils.touch "bin/something.bin"
-        FileUtils.touch "README"
-        system "git", "add", "--all"
-        system "git", "commit", "-m", "Initial repo commit"
-      end
-    end
-
-    setup_test_formula "testball1", <<-EOS.undent
-      version "1.0"
-      head "file://#{repo_path}", :using => :git
-      def install
-        prefix.install Dir["*"]
-      end
-    EOS
-
-    # Ignore dependencies, because we'll try to resolve requirements in build.rb
-    # and there will be the git requirement, but we cannot instantiate git
-    # formula since we only have testball1 formula.
-    assert_match "#{HOMEBREW_CELLAR}/testball1/HEAD-2ccdf4f", cmd("install", "testball1", "--HEAD", "--ignore-dependencies")
-    assert_match "testball1-HEAD-2ccdf4f already installed",
-      cmd("install", "testball1", "--HEAD", "--ignore-dependencies")
-    assert_match "#{HOMEBREW_CELLAR}/testball1/HEAD-2ccdf4f", cmd("unlink", "testball1")
-    assert_match "#{HOMEBREW_CELLAR}/testball1/1.0", cmd("install", "testball1")
-
-  ensure
-    ENV.replace(initial_env)
-    repo_path.rmtree
-  end
-
-  def test_install_with_invalid_option
-    setup_test_formula "testball1"
-    assert_match "testball1: this formula has no --with-fo option so it will be ignored!",
-      cmd("install", "testball1", "--with-fo")
-  end
-
-  def test_install_with_nonfatal_requirement
-    setup_test_formula "testball1", <<-EOS.undent
-      class NonFatalRequirement < Requirement
-        satisfy { false }
-      end
-      depends_on NonFatalRequirement
-    EOS
-    message = "NonFatalRequirement unsatisfied!"
-    assert_equal 1, cmd("install", "testball1").scan(message).size
-  end
-
-  def test_install_with_fatal_requirement
-    setup_test_formula "testball1", <<-EOS.undent
-      class FatalRequirement < Requirement
-        fatal true
-        satisfy { false }
-      end
-      depends_on FatalRequirement
-    EOS
-    message = "FatalRequirement unsatisfied!"
-    assert_equal 1, cmd_fail("install", "testball1").scan(message).size
-  end
-end
diff --git a/Library/Homebrew/test/irb_test.rb b/Library/Homebrew/test/irb_test.rb
deleted file mode 100644
index 832ca39a5..000000000
--- a/Library/Homebrew/test/irb_test.rb
+++ /dev/null
@@ -1,19 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestIrb < IntegrationCommandTestCase
-  def test_irb
-    assert_match "'v8'.f # => instance of the v8 formula",
-      cmd("irb", "--examples")
-
-    setup_test_formula "testball"
-
-    irb_test = HOMEBREW_TEMP/"irb-test.rb"
-    irb_test.write <<-EOS.undent
-      "testball".f
-      :testball.f
-      exit
-    EOS
-
-    assert_match "Interactive Homebrew Shell", cmd("irb", irb_test)
-  end
-end
diff --git a/Library/Homebrew/test/java_requirement_spec.rb b/Library/Homebrew/test/java_requirement_spec.rb
new file mode 100644
index 000000000..5adf64c7c
--- /dev/null
+++ b/Library/Homebrew/test/java_requirement_spec.rb
@@ -0,0 +1,107 @@
+require "requirements/java_requirement"
+
+describe JavaRequirement do
+  subject { described_class.new([]) }
+
+  before(:each) do
+    ENV["JAVA_HOME"] = nil
+  end
+
+  describe "#message" do
+    its(:message) { is_expected.to match(/Java is required to install this formula./) }
+  end
+
+  describe "#inspect" do
+    subject { described_class.new(%w[1.7+]) }
+    its(:inspect) { is_expected.to eq('#<JavaRequirement: "java" [] version="1.7+">') }
+  end
+
+  describe "#display_s" do
+    context "without specific version" do
+      its(:display_s) { is_expected.to eq("java") }
+    end
+
+    context "with version 1.8" do
+      subject { described_class.new(%w[1.8]) }
+      its(:display_s) { is_expected.to eq("java = 1.8") }
+    end
+
+    context "with version 1.8+" do
+      subject { described_class.new(%w[1.8+]) }
+      its(:display_s) { is_expected.to eq("java >= 1.8") }
+    end
+  end
+
+  describe "#satisfied?" do
+    subject { described_class.new(%w[1.8]) }
+
+    it "returns false if no `java` executable can be found" do
+      allow(File).to receive(:executable?).and_return(false)
+      expect(subject).not_to be_satisfied
+    end
+
+    it "returns true if #preferred_java returns a path" do
+      allow(subject).to receive(:preferred_java).and_return(Pathname.new("/usr/bin/java"))
+      expect(subject).to be_satisfied
+    end
+
+    context "when #possible_javas contains paths" do
+      let(:path) { Pathname.new(Dir.mktmpdir) }
+      let(:java) { path/"java" }
+
+      def setup_java_with_version(version)
+        IO.write java, <<-EOS.undent
+          #!/bin/sh
+          echo 'java version "#{version}"'
+        EOS
+        FileUtils.chmod "+x", java
+      end
+
+      before(:each) do
+        allow(subject).to receive(:possible_javas).and_return([java])
+      end
+
+      after(:each) do
+        path.rmtree
+      end
+
+      context "and 1.7 is required" do
+        subject { described_class.new(%w[1.7]) }
+
+        it "returns false if all are lower" do
+          setup_java_with_version "1.6.0_5"
+          expect(subject).not_to be_satisfied
+        end
+
+        it "returns true if one is equal" do
+          setup_java_with_version "1.7.0_5"
+          expect(subject).to be_satisfied
+        end
+
+        it "returns false if all are higher" do
+          setup_java_with_version "1.8.0_5"
+          expect(subject).not_to be_satisfied
+        end
+      end
+
+      context "and 1.7+ is required" do
+        subject { described_class.new(%w[1.7+]) }
+
+        it "returns false if all are lower" do
+          setup_java_with_version "1.6.0_5"
+          expect(subject).not_to be_satisfied
+        end
+
+        it "returns true if one is equal" do
+          setup_java_with_version "1.7.0_5"
+          expect(subject).to be_satisfied
+        end
+
+        it "returns true if one is higher" do
+          setup_java_with_version "1.8.0_5"
+          expect(subject).to be_satisfied
+        end
+      end
+    end
+  end
+end
diff --git a/Library/Homebrew/test/json_test.rb b/Library/Homebrew/test/json_test.rb
deleted file mode 100644
index 7c4c3671d..000000000
--- a/Library/Homebrew/test/json_test.rb
+++ /dev/null
@@ -1,20 +0,0 @@
-require "testing_env"
-require "json"
-
-class JsonSmokeTest < Homebrew::TestCase
-  def test_encode
-    hash = { "foo" => ["bar", "baz"] }
-    json = '{"foo":["bar","baz"]}'
-    assert_equal json, JSON.generate(hash)
-  end
-
-  def test_decode
-    hash = { "foo" => ["bar", "baz"], "qux" => 1 }
-    json = '{"foo":["bar","baz"],"qux":1}'
-    assert_equal hash, JSON.parse(json)
-  end
-
-  def test_decode_failure
-    assert_raises(JSON::ParserError) { JSON.parse("nope") }
-  end
-end
diff --git a/Library/Homebrew/test/keg_spec.rb b/Library/Homebrew/test/keg_spec.rb
new file mode 100644
index 000000000..f40002dd2
--- /dev/null
+++ b/Library/Homebrew/test/keg_spec.rb
@@ -0,0 +1,486 @@
+require "keg"
+require "stringio"
+
+describe Keg do
+  include FileUtils
+
+  def setup_test_keg(name, version)
+    path = HOMEBREW_CELLAR/name/version
+    (path/"bin").mkpath
+
+    %w[hiworld helloworld goodbye_cruel_world].each do |file|
+      touch path/"bin"/file
+    end
+
+    keg = described_class.new(path)
+    kegs << keg
+    keg
+  end
+
+  around(:each) do |example|
+    begin
+      @old_stdout = $stdout
+      $stdout = StringIO.new
+
+      example.run
+    ensure
+      $stdout = @old_stdout
+    end
+  end
+
+  let(:dst) { HOMEBREW_PREFIX/"bin"/"helloworld" }
+  let(:nonexistent) { Pathname.new("/some/nonexistent/path") }
+  let(:mode) { OpenStruct.new }
+  let!(:keg) { setup_test_keg("foo", "1.0") }
+  let(:kegs) { [] }
+
+  before(:each) do
+    (HOMEBREW_PREFIX/"bin").mkpath
+    (HOMEBREW_PREFIX/"lib").mkpath
+  end
+
+  after(:each) do
+    kegs.each(&:unlink)
+    rmtree HOMEBREW_PREFIX/"lib"
+  end
+
+  specify "::all" do
+    Formula.clear_racks_cache
+    expect(described_class.all).to eq([keg])
+  end
+
+  specify "#empty_installation?" do
+    %w[.DS_Store INSTALL_RECEIPT.json LICENSE.txt].each do |file|
+      touch keg/file
+    end
+
+    expect(keg).to exist
+    expect(keg).to be_a_directory
+    expect(keg).not_to be_an_empty_installation
+
+    (keg/"bin").rmtree
+    expect(keg).to be_an_empty_installation
+  end
+
+  specify "#oldname_opt_record" do
+    expect(keg.oldname_opt_record).to be nil
+    oldname_opt_record = HOMEBREW_PREFIX/"opt/oldfoo"
+    oldname_opt_record.make_relative_symlink(HOMEBREW_CELLAR/"foo/1.0")
+    expect(keg.oldname_opt_record).to eq(oldname_opt_record)
+  end
+
+  specify "#remove_oldname_opt_record" do
+    oldname_opt_record = HOMEBREW_PREFIX/"opt/oldfoo"
+    oldname_opt_record.make_relative_symlink(HOMEBREW_CELLAR/"foo/2.0")
+    keg.remove_oldname_opt_record
+    expect(oldname_opt_record).to be_a_symlink
+    oldname_opt_record.unlink
+    oldname_opt_record.make_relative_symlink(HOMEBREW_CELLAR/"foo/1.0")
+    keg.remove_oldname_opt_record
+    expect(oldname_opt_record).not_to be_a_symlink
+  end
+
+  describe "#link" do
+    it "links a Keg" do
+      expect(keg.link).to eq(3)
+      (HOMEBREW_PREFIX/"bin").children.each do |c|
+        expect(c.readlink).to be_relative
+      end
+    end
+
+    context "with dry run set to true" do
+      it "only prints what would be done" do
+        mode.dry_run = true
+
+        expect(keg.link(mode)).to eq(0)
+        expect(keg).not_to be_linked
+
+        ["hiworld", "helloworld", "goodbye_cruel_world"].each do |file|
+          expect($stdout.string).to match("#{HOMEBREW_PREFIX}/bin/#{file}")
+        end
+        expect($stdout.string.lines.count).to eq(3)
+      end
+    end
+
+    it "fails when already linked" do
+      keg.link
+
+      expect { keg.link }.to raise_error(Keg::AlreadyLinkedError)
+    end
+
+    it "fails when files exist" do
+      touch dst
+
+      expect { keg.link }.to raise_error(Keg::ConflictError)
+    end
+
+    it "ignores broken symlinks at target" do
+      src = keg/"bin"/"helloworld"
+      dst.make_symlink(nonexistent)
+      keg.link
+      expect(dst.readlink).to eq(src.relative_path_from(dst.dirname))
+    end
+
+    context "with overwrite set to true" do
+      it "overwrite existing files" do
+        touch dst
+        mode.overwrite = true
+        expect(keg.link(mode)).to eq(3)
+        expect(keg).to be_linked
+      end
+
+      it "overwrites broken symlinks" do
+        dst.make_symlink "nowhere"
+        mode.overwrite = true
+        expect(keg.link(mode)).to eq(3)
+        expect(keg).to be_linked
+      end
+
+      it "still supports dryrun" do
+        touch dst
+        mode.overwrite = true
+        mode.dry_run = true
+
+        expect(keg.link(mode)).to eq(0)
+        expect(keg).not_to be_linked
+
+        expect($stdout.string).to eq("#{dst}\n")
+      end
+    end
+
+    it "also creates an opt link" do
+      expect(keg).not_to be_optlinked
+      keg.link
+      expect(keg).to be_optlinked
+    end
+
+    specify "pkgconfig directory is created" do
+      link = HOMEBREW_PREFIX/"lib"/"pkgconfig"
+      (keg/"lib"/"pkgconfig").mkpath
+      keg.link
+      expect(link.lstat).to be_a_directory
+    end
+
+    specify "cmake directory is created" do
+      link = HOMEBREW_PREFIX/"lib"/"cmake"
+      (keg/"lib"/"cmake").mkpath
+      keg.link
+      expect(link.lstat).to be_a_directory
+    end
+
+    specify "symlinks are linked directly" do
+      link = HOMEBREW_PREFIX/"lib"/"pkgconfig"
+
+      (keg/"lib"/"example").mkpath
+      (keg/"lib"/"pkgconfig").make_symlink "example"
+      keg.link
+
+      expect(link.resolved_path).to be_a_symlink
+      expect(link.lstat).to be_a_symlink
+    end
+  end
+
+  describe "#unlink" do
+    it "unlinks a Keg" do
+      keg.link
+      expect(dst).to be_a_symlink
+      expect(keg.unlink).to eq(3)
+      expect(dst).not_to be_a_symlink
+    end
+
+    it "prunes empty top-level directories" do
+      mkpath HOMEBREW_PREFIX/"lib/foo/bar"
+      mkpath keg/"lib/foo/bar"
+      touch keg/"lib/foo/bar/file1"
+
+      keg.unlink
+
+      expect(HOMEBREW_PREFIX/"lib/foo").not_to be_a_directory
+    end
+
+    it "ignores .DS_Store when pruning empty directories" do
+      mkpath HOMEBREW_PREFIX/"lib/foo/bar"
+      touch HOMEBREW_PREFIX/"lib/foo/.DS_Store"
+      mkpath keg/"lib/foo/bar"
+      touch keg/"lib/foo/bar/file1"
+
+      keg.unlink
+
+      expect(HOMEBREW_PREFIX/"lib/foo").not_to be_a_directory
+      expect(HOMEBREW_PREFIX/"lib/foo/.DS_Store").not_to exist
+    end
+
+    it "doesn't remove opt link" do
+      keg.link
+      keg.unlink
+      expect(keg).to be_optlinked
+    end
+
+    it "preverves broken symlinks pointing outside the Keg" do
+      keg.link
+      dst.delete
+      dst.make_symlink(nonexistent)
+      keg.unlink
+      expect(dst).to be_a_symlink
+    end
+
+    it "preverves broken symlinks pointing into the Keg" do
+      keg.link
+      dst.resolved_path.delete
+      keg.unlink
+      expect(dst).to be_a_symlink
+    end
+
+    it "preverves symlinks pointing outside the Keg" do
+      keg.link
+      dst.delete
+      dst.make_symlink(Pathname.new("/bin/sh"))
+      keg.unlink
+      expect(dst).to be_a_symlink
+    end
+
+    it "preserves real files" do
+      keg.link
+      dst.delete
+      touch dst
+      keg.unlink
+      expect(dst).to be_a_file
+    end
+
+    it "ignores nonexistent file" do
+      keg.link
+      dst.delete
+      expect(keg.unlink).to eq(2)
+    end
+
+    it "doesn't remove links to symlinks" do
+      a = HOMEBREW_CELLAR/"a"/"1.0"
+      b = HOMEBREW_CELLAR/"b"/"1.0"
+
+      (a/"lib"/"example").mkpath
+      (a/"lib"/"example2").make_symlink "example"
+      (b/"lib"/"example2").mkpath
+
+      a = described_class.new(a)
+      b = described_class.new(b)
+      a.link
+
+      lib = HOMEBREW_PREFIX/"lib"
+      expect(lib.children.length).to eq(2)
+      expect { b.link }.to raise_error(Keg::ConflictError)
+      expect(lib.children.length).to eq(2)
+    end
+
+    it "removes broken symlinks that conflict with directories" do
+      a = HOMEBREW_CELLAR/"a"/"1.0"
+      (a/"lib"/"foo").mkpath
+
+      keg = described_class.new(a)
+
+      link = HOMEBREW_PREFIX/"lib"/"foo"
+      link.parent.mkpath
+      link.make_symlink(nonexistent)
+
+      keg.link
+    end
+  end
+
+  describe "#optlink" do
+    it "creates an opt link" do
+      oldname_opt_record = HOMEBREW_PREFIX/"opt/oldfoo"
+      oldname_opt_record.make_relative_symlink(HOMEBREW_CELLAR/"foo/1.0")
+      keg_record = HOMEBREW_CELLAR/"foo"/"2.0"
+      (keg_record/"bin").mkpath
+      keg = described_class.new(keg_record)
+      keg.optlink
+      expect(keg_record).to eq(oldname_opt_record.resolved_path)
+      keg.uninstall
+      expect(oldname_opt_record).not_to be_a_symlink
+    end
+
+    it "doesn't fail if already opt-linked" do
+      keg.opt_record.make_relative_symlink Pathname.new(keg)
+      keg.optlink
+      expect(keg).to be_optlinked
+    end
+
+    it "replaces an existing directory" do
+      keg.opt_record.mkpath
+      keg.optlink
+      expect(keg).to be_optlinked
+    end
+
+    it "replaces an existing file" do
+      keg.opt_record.parent.mkpath
+      keg.opt_record.write("foo")
+      keg.optlink
+      expect(keg).to be_optlinked
+    end
+  end
+
+  specify "#link and #unlink" do
+    expect(keg).not_to be_linked
+    keg.link
+    expect(keg).to be_linked
+    keg.unlink
+    expect(keg).not_to be_linked
+  end
+
+  describe "::find_some_installed_dependents" do
+    def stub_formula_name(name)
+      f = formula(name) { url "foo-1.0" }
+      stub_formula_loader f
+      stub_formula_loader f, "homebrew/core/#{f}"
+      f
+    end
+
+    def setup_test_keg(name, version)
+      f = stub_formula_name(name)
+      keg = super
+      Tab.create(f, DevelopmentTools.default_compiler, :libcxx).write
+      keg
+    end
+
+    before(:each) do
+      keg.link
+    end
+
+    def alter_tab(keg = dependent)
+      tab = Tab.for_keg(keg)
+      yield tab
+      tab.write
+    end
+
+    # 1.1.6 is the earliest version of Homebrew that generates correct runtime
+    # dependency lists in Tabs.
+    def dependencies(deps, homebrew_version: "1.1.6")
+      alter_tab do |tab|
+        tab.homebrew_version = homebrew_version
+        tab.tabfile = dependent/Tab::FILENAME
+        tab.runtime_dependencies = deps
+      end
+    end
+
+    def unreliable_dependencies(deps)
+      # 1.1.5 is (hopefully!) the last version of Homebrew that generates
+      # incorrect runtime dependency lists in Tabs.
+      dependencies(deps, homebrew_version: "1.1.5")
+    end
+
+    let(:dependent) { setup_test_keg("bar", "1.0") }
+
+    # Test with a keg whose formula isn't known.
+    # This can happen if e.g. a formula is installed
+    # from a file path or URL.
+    specify "unknown Formula" do
+      allow(Formulary).to receive(:loader_for).and_call_original
+      alter_tab(keg) do |t|
+        t.source["tap"] = "some/tap"
+        t.source["path"] = nil
+      end
+
+      dependencies [{ "full_name" => "some/tap/foo", "version" => "1.0" }]
+      expect(keg.installed_dependents).to eq([dependent])
+      expect(described_class.find_some_installed_dependents([keg])).to eq([[keg], ["bar 1.0"]])
+
+      dependencies nil
+      # It doesn't make sense for a keg with no formula to have any dependents,
+      # so that can't really be tested.
+      expect(described_class.find_some_installed_dependents([keg])).to be nil
+    end
+
+    specify "a dependency with no Tap in Tab" do
+      tap_dep = setup_test_keg("baz", "1.0")
+
+      alter_tab(keg) { |t| t.source["tap"] = nil }
+
+      dependencies nil
+      Formula["bar"].class.depends_on "foo"
+      Formula["bar"].class.depends_on "baz"
+
+      result = described_class.find_some_installed_dependents([keg, tap_dep])
+      expect(result).to eq([[keg, tap_dep], ["bar"]])
+    end
+
+    specify "no dependencies anywhere" do
+      dependencies nil
+      expect(keg.installed_dependents).to be_empty
+      expect(described_class.find_some_installed_dependents([keg])).to be nil
+    end
+
+    specify "missing Formula dependency" do
+      dependencies nil
+      Formula["bar"].class.depends_on "foo"
+      expect(keg.installed_dependents).to be_empty
+      expect(described_class.find_some_installed_dependents([keg])).to eq([[keg], ["bar"]])
+    end
+
+    specify "uninstalling dependent and dependency" do
+      dependencies nil
+      Formula["bar"].class.depends_on "foo"
+      expect(keg.installed_dependents).to be_empty
+      expect(described_class.find_some_installed_dependents([keg, dependent])).to be nil
+    end
+
+    specify "renamed dependency" do
+      dependencies nil
+
+      stub_formula_loader Formula["foo"], "homebrew/core/foo-old"
+      renamed_path = HOMEBREW_CELLAR/"foo-old"
+      (HOMEBREW_CELLAR/"foo").rename(renamed_path)
+      renamed_keg = described_class.new(renamed_path/"1.0")
+
+      Formula["bar"].class.depends_on "foo"
+
+      result = described_class.find_some_installed_dependents([renamed_keg])
+      expect(result).to eq([[renamed_keg], ["bar"]])
+    end
+
+    specify "empty dependencies in Tab" do
+      dependencies []
+      expect(keg.installed_dependents).to be_empty
+      expect(described_class.find_some_installed_dependents([keg])).to be nil
+    end
+
+    specify "same name but different version in Tab" do
+      dependencies [{ "full_name" => "foo", "version" => "1.1" }]
+      expect(keg.installed_dependents).to eq([dependent])
+      expect(described_class.find_some_installed_dependents([keg])).to eq([[keg], ["bar 1.0"]])
+    end
+
+    specify "different name and same version in Tab" do
+      stub_formula_name("baz")
+      dependencies [{ "full_name" => "baz", "version" => keg.version.to_s }]
+      expect(keg.installed_dependents).to be_empty
+      expect(described_class.find_some_installed_dependents([keg])).to be nil
+    end
+
+    specify "same name and version in Tab" do
+      dependencies [{ "full_name" => "foo", "version" => "1.0" }]
+      expect(keg.installed_dependents).to eq([dependent])
+      expect(described_class.find_some_installed_dependents([keg])).to eq([[keg], ["bar 1.0"]])
+    end
+
+    specify "fallback for old versions" do
+      unreliable_dependencies [{ "full_name" => "baz", "version" => "1.0" }]
+      Formula["bar"].class.depends_on "foo"
+      expect(keg.installed_dependents).to be_empty
+      expect(described_class.find_some_installed_dependents([keg])).to eq([[keg], ["bar"]])
+    end
+
+    specify "non-opt-linked" do
+      keg.remove_opt_record
+      dependencies [{ "full_name" => "foo", "version" => "1.0" }]
+      expect(keg.installed_dependents).to be_empty
+      expect(described_class.find_some_installed_dependents([keg])).to be nil
+    end
+
+    specify "keg-only" do
+      keg.unlink
+      Formula["foo"].class.keg_only "a good reason"
+      dependencies [{ "full_name" => "foo", "version" => "1.1" }] # different version
+      expect(keg.installed_dependents).to eq([dependent])
+      expect(described_class.find_some_installed_dependents([keg])).to eq([[keg], ["bar 1.0"]])
+    end
+  end
+end
diff --git a/Library/Homebrew/test/keg_test.rb b/Library/Homebrew/test/keg_test.rb
deleted file mode 100644
index 40b47b5e9..000000000
--- a/Library/Homebrew/test/keg_test.rb
+++ /dev/null
@@ -1,484 +0,0 @@
-require "testing_env"
-require "keg"
-require "stringio"
-
-class LinkTestCase < Homebrew::TestCase
-  include FileUtils
-
-  def setup_test_keg(name, version)
-    path = HOMEBREW_CELLAR.join(name, version)
-    path.join("bin").mkpath
-
-    %w[hiworld helloworld goodbye_cruel_world].each do |file|
-      touch path.join("bin", file)
-    end
-
-    keg = Keg.new(path)
-    @kegs ||= []
-    @kegs << keg
-    keg
-  end
-
-  def setup
-    @keg = setup_test_keg("foo", "1.0")
-    @dst = HOMEBREW_PREFIX.join("bin", "helloworld")
-    @nonexistent = Pathname.new("/some/nonexistent/path")
-
-    @mode = OpenStruct.new
-
-    @old_stdout = $stdout
-    $stdout = StringIO.new
-
-    mkpath HOMEBREW_PREFIX/"bin"
-    mkpath HOMEBREW_PREFIX/"lib"
-  end
-
-  def teardown
-    @kegs.each do |keg|
-      keg.unlink
-      keg.uninstall
-    end
-
-    $stdout = @old_stdout
-
-    rmtree HOMEBREW_PREFIX/"bin"
-    rmtree HOMEBREW_PREFIX/"lib"
-  end
-end
-
-class LinkTests < LinkTestCase
-  def test_all
-    Formula.clear_racks_cache
-    assert_equal [@keg], Keg.all
-  end
-
-  def test_empty_installation
-    %w[.DS_Store INSTALL_RECEIPT.json LICENSE.txt].each do |file|
-      touch @keg/file
-    end
-    assert_predicate @keg, :exist?
-    assert_predicate @keg, :directory?
-    refute_predicate @keg, :empty_installation?
-
-    (@keg/"bin").rmtree
-    assert_predicate @keg, :empty_installation?
-  end
-
-  def test_linking_keg
-    assert_equal 3, @keg.link
-    (HOMEBREW_PREFIX/"bin").children.each { |c| assert_predicate c.readlink, :relative? }
-  end
-
-  def test_unlinking_keg
-    @keg.link
-    assert_predicate @dst, :symlink?
-    assert_equal 3, @keg.unlink
-    refute_predicate @dst, :symlink?
-  end
-
-  def test_oldname_opt_record
-    assert_nil @keg.oldname_opt_record
-    oldname_opt_record = HOMEBREW_PREFIX/"opt/oldfoo"
-    oldname_opt_record.make_relative_symlink(HOMEBREW_CELLAR/"foo/1.0")
-    assert_equal oldname_opt_record, @keg.oldname_opt_record
-  end
-
-  def test_optlink_relink
-    oldname_opt_record = HOMEBREW_PREFIX/"opt/oldfoo"
-    oldname_opt_record.make_relative_symlink(HOMEBREW_CELLAR/"foo/1.0")
-    keg_record = HOMEBREW_CELLAR.join("foo", "2.0")
-    keg_record.join("bin").mkpath
-    keg = Keg.new(keg_record)
-    keg.optlink
-    assert_equal keg_record, oldname_opt_record.resolved_path
-    keg.uninstall
-    refute_predicate oldname_opt_record, :symlink?
-  end
-
-  def test_remove_oldname_opt_record
-    oldname_opt_record = HOMEBREW_PREFIX/"opt/oldfoo"
-    oldname_opt_record.make_relative_symlink(HOMEBREW_CELLAR/"foo/2.0")
-    @keg.remove_oldname_opt_record
-    assert_predicate oldname_opt_record, :symlink?
-    oldname_opt_record.unlink
-    oldname_opt_record.make_relative_symlink(HOMEBREW_CELLAR/"foo/1.0")
-    @keg.remove_oldname_opt_record
-    refute_predicate oldname_opt_record, :symlink?
-  end
-
-  def test_link_dry_run
-    @mode.dry_run = true
-
-    assert_equal 0, @keg.link(@mode)
-    refute_predicate @keg, :linked?
-
-    ["hiworld", "helloworld", "goodbye_cruel_world"].each do |file|
-      assert_match "#{HOMEBREW_PREFIX}/bin/#{file}", $stdout.string
-    end
-    assert_equal 3, $stdout.string.lines.count
-  end
-
-  def test_linking_fails_when_already_linked
-    @keg.link
-    assert_raises(Keg::AlreadyLinkedError) { @keg.link }
-  end
-
-  def test_linking_fails_when_files_exist
-    touch @dst
-    assert_raises(Keg::ConflictError) { @keg.link }
-  end
-
-  def test_link_ignores_broken_symlinks_at_target
-    src = @keg.join("bin", "helloworld")
-    @dst.make_symlink(@nonexistent)
-    @keg.link
-    assert_equal src.relative_path_from(@dst.dirname), @dst.readlink
-  end
-
-  def test_link_overwrite
-    touch @dst
-    @mode.overwrite = true
-    assert_equal 3, @keg.link(@mode)
-    assert_predicate @keg, :linked?
-  end
-
-  def test_link_overwrite_broken_symlinks
-    @dst.make_symlink "nowhere"
-    @mode.overwrite = true
-    assert_equal 3, @keg.link(@mode)
-    assert_predicate @keg, :linked?
-  end
-
-  def test_link_overwrite_dryrun
-    touch @dst
-    @mode.overwrite = true
-    @mode.dry_run = true
-
-    assert_equal 0, @keg.link(@mode)
-    refute_predicate @keg, :linked?
-
-    assert_equal "#{@dst}\n", $stdout.string
-  end
-
-  def test_unlink_prunes_empty_toplevel_directories
-    mkpath HOMEBREW_PREFIX/"lib/foo/bar"
-    mkpath @keg/"lib/foo/bar"
-    touch @keg/"lib/foo/bar/file1"
-
-    @keg.unlink
-
-    refute_predicate HOMEBREW_PREFIX/"lib/foo", :directory?
-  end
-
-  def test_unlink_ignores_ds_store_when_pruning_empty_dirs
-    mkpath HOMEBREW_PREFIX/"lib/foo/bar"
-    touch HOMEBREW_PREFIX/"lib/foo/.DS_Store"
-    mkpath @keg/"lib/foo/bar"
-    touch @keg/"lib/foo/bar/file1"
-
-    @keg.unlink
-
-    refute_predicate HOMEBREW_PREFIX/"lib/foo", :directory?
-    refute_predicate HOMEBREW_PREFIX/"lib/foo/.DS_Store", :exist?
-  end
-
-  def test_linking_creates_opt_link
-    refute_predicate @keg, :optlinked?
-    @keg.link
-    assert_predicate @keg, :optlinked?
-  end
-
-  def test_unlinking_does_not_remove_opt_link
-    @keg.link
-    @keg.unlink
-    assert_predicate @keg, :optlinked?
-  end
-
-  def test_existing_opt_link
-    @keg.opt_record.make_relative_symlink Pathname.new(@keg)
-    @keg.optlink
-    assert_predicate @keg, :optlinked?
-  end
-
-  def test_existing_opt_link_directory
-    @keg.opt_record.mkpath
-    @keg.optlink
-    assert_predicate @keg, :optlinked?
-  end
-
-  def test_existing_opt_link_file
-    @keg.opt_record.parent.mkpath
-    @keg.opt_record.write("foo")
-    @keg.optlink
-    assert_predicate @keg, :optlinked?
-  end
-
-  def test_linked_keg
-    refute_predicate @keg, :linked?
-    @keg.link
-    assert_predicate @keg, :linked?
-    @keg.unlink
-    refute_predicate @keg, :linked?
-  end
-
-  def test_unlink_preserves_broken_symlink_pointing_outside_the_keg
-    @keg.link
-    @dst.delete
-    @dst.make_symlink(@nonexistent)
-    @keg.unlink
-    assert_predicate @dst, :symlink?
-  end
-
-  def test_unlink_preserves_broken_symlink_pointing_into_the_keg
-    @keg.link
-    @dst.resolved_path.delete
-    @keg.unlink
-    assert_predicate @dst, :symlink?
-  end
-
-  def test_unlink_preserves_symlink_pointing_outside_of_keg
-    @keg.link
-    @dst.delete
-    @dst.make_symlink(Pathname.new("/bin/sh"))
-    @keg.unlink
-    assert_predicate @dst, :symlink?
-  end
-
-  def test_unlink_preserves_real_file
-    @keg.link
-    @dst.delete
-    touch @dst
-    @keg.unlink
-    assert_predicate @dst, :file?
-  end
-
-  def test_unlink_ignores_nonexistent_file
-    @keg.link
-    @dst.delete
-    assert_equal 2, @keg.unlink
-  end
-
-  def test_pkgconfig_is_mkpathed
-    link = HOMEBREW_PREFIX.join("lib", "pkgconfig")
-    @keg.join("lib", "pkgconfig").mkpath
-    @keg.link
-    assert_predicate link.lstat, :directory?
-  end
-
-  def test_cmake_is_mkpathed
-    link = HOMEBREW_PREFIX.join("lib", "cmake")
-    @keg.join("lib", "cmake").mkpath
-    @keg.link
-    assert_predicate link.lstat, :directory?
-  end
-
-  def test_symlinks_are_linked_directly
-    link = HOMEBREW_PREFIX.join("lib", "pkgconfig")
-
-    @keg.join("lib", "example").mkpath
-    @keg.join("lib", "pkgconfig").make_symlink "example"
-    @keg.link
-
-    assert_predicate link.resolved_path, :symlink?
-    assert_predicate link.lstat, :symlink?
-  end
-
-  def test_links_to_symlinks_are_not_removed
-    a = HOMEBREW_CELLAR.join("a", "1.0")
-    b = HOMEBREW_CELLAR.join("b", "1.0")
-
-    a.join("lib", "example").mkpath
-    a.join("lib", "example2").make_symlink "example"
-    b.join("lib", "example2").mkpath
-
-    a = Keg.new(a)
-    b = Keg.new(b)
-    a.link
-
-    lib = HOMEBREW_PREFIX.join("lib")
-    assert_equal 2, lib.children.length
-    assert_raises(Keg::ConflictError) { b.link }
-    assert_equal 2, lib.children.length
-  ensure
-    a.unlink
-    a.uninstall
-    b.uninstall
-  end
-
-  def test_removes_broken_symlinks_that_conflict_with_directories
-    a = HOMEBREW_CELLAR.join("a", "1.0")
-    a.join("lib", "foo").mkpath
-
-    keg = Keg.new(a)
-
-    link = HOMEBREW_PREFIX.join("lib", "foo")
-    link.parent.mkpath
-    link.make_symlink(@nonexistent)
-
-    keg.link
-  ensure
-    keg.unlink
-    keg.uninstall
-  end
-end
-
-class InstalledDependantsTests < LinkTestCase
-  def stub_formula_name(name)
-    f = formula(name) { url "foo-1.0" }
-    stub_formula_loader f
-    stub_formula_loader f, "homebrew/core/#{f}"
-    f
-  end
-
-  def setup_test_keg(name, version)
-    f = stub_formula_name(name)
-    keg = super
-    Tab.create(f, DevelopmentTools.default_compiler, :libcxx).write
-    keg
-  end
-
-  def setup
-    super
-    @dependent = setup_test_keg("bar", "1.0")
-    @keg.link
-  end
-
-  def alter_tab(keg = @dependent)
-    tab = Tab.for_keg(keg)
-    yield tab
-    tab.write
-  end
-
-  # 1.1.6 is the earliest version of Homebrew that generates correct runtime
-  # dependency lists in tabs.
-  def dependencies(deps, homebrew_version: "1.1.6")
-    alter_tab do |tab|
-      tab.homebrew_version = homebrew_version
-      tab.tabfile = @dependent.join("INSTALL_RECEIPT.json")
-      tab.runtime_dependencies = deps
-    end
-  end
-
-  def unreliable_dependencies(deps)
-    # 1.1.5 is (hopefully!) the last version of Homebrew that generates
-    # incorrect runtime dependency lists in tabs.
-    dependencies(deps, homebrew_version: "1.1.5")
-  end
-
-  # Test with a keg whose formula isn't known.
-  # This can happen if e.g. a formula is installed
-  # from a file path or URL.
-  def test_unknown_formula
-    Formulary.unstub(:loader_for)
-    alter_tab(@keg) do |t|
-      t.source["tap"] = "some/tap"
-      t.source["path"] = nil
-    end
-
-    dependencies [{ "full_name" => "some/tap/foo", "version" => "1.0" }]
-    assert_equal [@dependent], @keg.installed_dependents
-    assert_equal [[@keg], ["bar 1.0"]], Keg.find_some_installed_dependents([@keg])
-
-    dependencies nil
-    # It doesn't make sense for a keg with no formula to have any dependents,
-    # so that can't really be tested.
-    assert_nil Keg.find_some_installed_dependents([@keg])
-  end
-
-  def test_a_dependency_with_no_tap_in_tab
-    @tap_dep = setup_test_keg("baz", "1.0")
-
-    alter_tab(@keg) { |t| t.source["tap"] = nil }
-
-    dependencies nil
-    Formula["bar"].class.depends_on "foo"
-    Formula["bar"].class.depends_on "baz"
-
-    result = Keg.find_some_installed_dependents([@keg, @tap_dep])
-    assert_equal [[@keg, @tap_dep], ["bar"]], result
-  end
-
-  def test_no_dependencies_anywhere
-    dependencies nil
-    assert_empty @keg.installed_dependents
-    assert_nil Keg.find_some_installed_dependents([@keg])
-  end
-
-  def test_missing_formula_dependency
-    dependencies nil
-    Formula["bar"].class.depends_on "foo"
-    assert_empty @keg.installed_dependents
-    assert_equal [[@keg], ["bar"]], Keg.find_some_installed_dependents([@keg])
-  end
-
-  def test_uninstalling_dependent_and_dependency
-    dependencies nil
-    Formula["bar"].class.depends_on "foo"
-    assert_empty @keg.installed_dependents
-    assert_nil Keg.find_some_installed_dependents([@keg, @dependent])
-  end
-
-  def test_renamed_dependency
-    dependencies nil
-
-    stub_formula_loader Formula["foo"], "homebrew/core/foo-old"
-    renamed_path = HOMEBREW_CELLAR/"foo-old"
-    (HOMEBREW_CELLAR/"foo").rename(renamed_path)
-    renamed_keg = Keg.new(renamed_path.join("1.0"))
-
-    Formula["bar"].class.depends_on "foo"
-
-    result = Keg.find_some_installed_dependents([renamed_keg])
-    assert_equal [[renamed_keg], ["bar"]], result
-  ensure
-    # Move it back to where it was so it'll be cleaned up.
-    (HOMEBREW_CELLAR/"foo-old").rename(HOMEBREW_CELLAR/"foo")
-  end
-
-  def test_empty_dependencies_in_tab
-    dependencies []
-    assert_empty @keg.installed_dependents
-    assert_nil Keg.find_some_installed_dependents([@keg])
-  end
-
-  def test_same_name_different_version_in_tab
-    dependencies [{ "full_name" => "foo", "version" => "1.1" }]
-    assert_equal [@dependent], @keg.installed_dependents
-    assert_equal [[@keg], ["bar 1.0"]], Keg.find_some_installed_dependents([@keg])
-  end
-
-  def test_different_name_same_version_in_tab
-    stub_formula_name("baz")
-    dependencies [{ "full_name" => "baz", "version" => @keg.version.to_s }]
-    assert_empty @keg.installed_dependents
-    assert_nil Keg.find_some_installed_dependents([@keg])
-  end
-
-  def test_same_name_and_version_in_tab
-    dependencies [{ "full_name" => "foo", "version" => "1.0" }]
-    assert_equal [@dependent], @keg.installed_dependents
-    assert_equal [[@keg], ["bar 1.0"]], Keg.find_some_installed_dependents([@keg])
-  end
-
-  def test_fallback_for_old_versions
-    unreliable_dependencies [{ "full_name" => "baz", "version" => "1.0" }]
-    Formula["bar"].class.depends_on "foo"
-    assert_empty @keg.installed_dependents
-    assert_equal [[@keg], ["bar"]], Keg.find_some_installed_dependents([@keg])
-  end
-
-  def test_nonoptlinked
-    @keg.remove_opt_record
-    dependencies [{ "full_name" => "foo", "version" => "1.0" }]
-    assert_empty @keg.installed_dependents
-    assert_nil Keg.find_some_installed_dependents([@keg])
-  end
-
-  def test_keg_only
-    @keg.unlink
-    Formula["foo"].class.keg_only "a good reason"
-    dependencies [{ "full_name" => "foo", "version" => "1.1" }] # different version
-    assert_equal [@dependent], @keg.installed_dependents
-    assert_equal [[@keg], ["bar 1.0"]], Keg.find_some_installed_dependents([@keg])
-  end
-end
diff --git a/Library/Homebrew/test/language/go_spec.rb b/Library/Homebrew/test/language/go_spec.rb
new file mode 100644
index 000000000..24db78594
--- /dev/null
+++ b/Library/Homebrew/test/language/go_spec.rb
@@ -0,0 +1,15 @@
+require "language/go"
+
+describe Language::Go do
+  specify "#stage_deps" do
+    ENV.delete("HOMEBREW_DEVELOPER")
+
+    expect(described_class).to receive(:opoo).once
+
+    Dir.mktmpdir do |path|
+      shutup do
+        described_class.stage_deps [], path
+      end
+    end
+  end
+end
diff --git a/Library/Homebrew/test/language/python_spec.rb b/Library/Homebrew/test/language/python_spec.rb
new file mode 100644
index 000000000..c78520897
--- /dev/null
+++ b/Library/Homebrew/test/language/python_spec.rb
@@ -0,0 +1,106 @@
+require "language/python"
+require "resource"
+
+describe Language::Python::Virtualenv::Virtualenv do
+  subject { described_class.new(formula, dir, "python") }
+
+  let(:dir) { @dir = Pathname.new(Dir.mktmpdir) }
+
+  let(:resource) { double("resource", stage: true) }
+  let(:formula_bin) { dir/"formula_bin" }
+  let(:formula) { double("formula", resource: resource, bin: formula_bin) }
+
+  after(:each) { dir.rmtree unless @dir.nil? }
+
+  describe "#create" do
+    it "creates a virtual environment" do
+      expect(formula).to receive(:resource).with("homebrew-virtualenv").and_return(resource)
+      subject.create
+    end
+
+    specify "virtual environment creation is idempotent" do
+      expect(formula).to receive(:resource).with("homebrew-virtualenv").and_return(resource)
+      subject.create
+      FileUtils.mkdir_p dir/"bin"
+      FileUtils.touch dir/"bin/python"
+      subject.create
+      FileUtils.rm dir/"bin/python"
+    end
+  end
+
+  describe "#pip_install" do
+    it "accepts a string" do
+      expect(formula).to receive(:system)
+        .with(dir/"bin/pip", "install", "-v", "--no-deps",
+              "--no-binary", ":all:", "--ignore-installed", "foo")
+        .and_return(true)
+      subject.pip_install "foo"
+    end
+
+    it "accepts a multi-line strings" do
+      expect(formula).to receive(:system)
+        .with(dir/"bin/pip", "install", "-v", "--no-deps",
+              "--no-binary", ":all:", "--ignore-installed", "foo", "bar")
+        .and_return(true)
+
+      subject.pip_install <<-EOS.undent
+        foo
+        bar
+      EOS
+    end
+
+    it "accepts an array" do
+      expect(formula).to receive(:system)
+        .with(dir/"bin/pip", "install", "-v", "--no-deps",
+              "--no-binary", ":all:", "--ignore-installed", "foo")
+        .and_return(true)
+
+      expect(formula).to receive(:system)
+        .with(dir/"bin/pip", "install", "-v", "--no-deps",
+              "--no-binary", ":all:", "--ignore-installed", "bar")
+        .and_return(true)
+
+      subject.pip_install ["foo", "bar"]
+    end
+
+    it "accepts a Resource" do
+      res = Resource.new("test")
+
+      expect(res).to receive(:stage).and_yield
+      expect(formula).to receive(:system)
+        .with(dir/"bin/pip", "install", "-v", "--no-deps",
+              "--no-binary", ":all:", "--ignore-installed", Pathname.pwd)
+        .and_return(true)
+
+      subject.pip_install res
+    end
+  end
+
+  describe "#pip_install_and_link" do
+    let(:src_bin) { dir/"bin" }
+    let(:dest_bin) { formula.bin }
+
+    it "can link scripts" do
+      src_bin.mkpath
+
+      expect(src_bin/"kilroy").not_to exist
+      expect(dest_bin/"kilroy").not_to exist
+
+      FileUtils.touch src_bin/"irrelevant"
+      bin_before = Dir.glob(src_bin/"*")
+      FileUtils.touch src_bin/"kilroy"
+      bin_after = Dir.glob(src_bin/"*")
+
+      expect(subject).to receive(:pip_install).with("foo")
+      expect(Dir).to receive(:[]).with(src_bin/"*").twice.and_return(bin_before, bin_after)
+
+      subject.pip_install_and_link "foo"
+
+      expect(src_bin/"kilroy").to exist
+      expect(dest_bin/"kilroy").to exist
+      expect(dest_bin/"kilroy").to be_a_symlink
+      expect((src_bin/"kilroy").realpath).to eq((dest_bin/"kilroy").realpath)
+      expect(dest_bin/"irrelevant").not_to exist
+    end
+  end
+end
diff --git a/Library/Homebrew/test/language_go_test.rb b/Library/Homebrew/test/language_go_test.rb
deleted file mode 100644
index 692a5d2cc..000000000
--- a/Library/Homebrew/test/language_go_test.rb
+++ /dev/null
@@ -1,17 +0,0 @@
-# -*- coding: UTF-8 -*-
-
-require "testing_env"
-require "language/go"
-
-class LanguageGoTests < Homebrew::TestCase
-  def test_stage_deps_empty
-    if ARGV.homebrew_developer?
-      Language::Go.expects(:odie).once
-    else
-      Language::Go.expects(:opoo).once
-    end
-    mktmpdir do |path|
-      shutup { Language::Go.stage_deps [], path }
-    end
-  end
-end
diff --git a/Library/Homebrew/test/language_module_requirement_spec.rb b/Library/Homebrew/test/language_module_requirement_spec.rb
new file mode 100644
index 000000000..7f2666855
--- /dev/null
+++ b/Library/Homebrew/test/language_module_requirement_spec.rb
@@ -0,0 +1,49 @@
+require "requirements/language_module_requirement"
+
+describe LanguageModuleRequirement do
+  specify "unique dependencies are not equal" do
+    x = described_class.new(:node, "less")
+    y = described_class.new(:node, "coffee-script")
+    expect(x).not_to eq(y)
+    expect(x.hash).not_to eq(y.hash)
+  end
+
+  context "when module and import name differ" do
+    subject { described_class.new(:python, mod_name, import_name) }
+    let(:mod_name) { "foo" }
+    let(:import_name) { "bar" }
+
+    its(:message) { is_expected.to include(mod_name) }
+    its(:the_test) { is_expected.to include("import #{import_name}") }
+  end
+
+  context "when the language is Perl" do
+    it "does not satisfy invalid dependencies" do
+      expect(described_class.new(:perl, "notapackage")).not_to be_satisfied
+    end
+
+    it "satisfies valid dependencies" do
+      expect(described_class.new(:perl, "Env")).to be_satisfied
+    end
+  end
+
+  context "when the language is Python", :needs_python do
+    it "does not satisfy invalid dependencies" do
+      expect(described_class.new(:python, "notapackage")).not_to be_satisfied
+    end
+
+    it "satisfies valid dependencies" do
+      expect(described_class.new(:python, "datetime")).to be_satisfied
+    end
+  end
+
+  context "when the language is Ruby" do
+    it "does not satisfy invalid dependencies" do
+      expect(described_class.new(:ruby, "notapackage")).not_to be_satisfied
+    end
+
+    it "satisfies valid dependencies" do
+      expect(described_class.new(:ruby, "date")).to be_satisfied
+    end
+  end
+end
diff --git a/Library/Homebrew/test/language_module_requirement_test.rb b/Library/Homebrew/test/language_module_requirement_test.rb
deleted file mode 100644
index dfa992287..000000000
--- a/Library/Homebrew/test/language_module_requirement_test.rb
+++ /dev/null
@@ -1,55 +0,0 @@
-require "testing_env"
-require "requirements/language_module_requirement"
-
-class LanguageModuleRequirementTests < Homebrew::TestCase
-  parallelize_me!
-
-  def assert_deps_fail(spec)
-    refute_predicate LanguageModuleRequirement.new(*spec.shift.reverse), :satisfied?
-  end
-
-  def assert_deps_pass(spec)
-    assert_predicate LanguageModuleRequirement.new(*spec.shift.reverse), :satisfied?
-  end
-
-  def test_unique_deps_are_not_eql
-    x = LanguageModuleRequirement.new(:node, "less")
-    y = LanguageModuleRequirement.new(:node, "coffee-script")
-    refute_eql x, y
-    refute_equal x.hash, y.hash
-  end
-
-  def test_differing_module_and_import_name
-    mod_name = "foo"
-    import_name = "bar"
-    l = LanguageModuleRequirement.new(:python, mod_name, import_name)
-    assert_includes l.message, mod_name
-    assert_includes l.the_test, "import #{import_name}"
-  end
-
-  def test_bad_perl_deps
-    assert_deps_fail "notapackage" => :perl
-  end
-
-  def test_good_perl_deps
-    assert_deps_pass "Env" => :perl
-  end
-
-  def test_bad_python_deps
-    needs_python
-    assert_deps_fail "notapackage" => :python
-  end
-
-  def test_good_python_deps
-    needs_python
-    assert_deps_pass "datetime" => :python
-  end
-
-  def test_bad_ruby_deps
-    assert_deps_fail "notapackage" => :ruby
-  end
-
-  def test_good_ruby_deps
-    assert_deps_pass "date" => :ruby
-  end
-end
diff --git a/Library/Homebrew/test/language_python_test.rb b/Library/Homebrew/test/language_python_test.rb
deleted file mode 100644
index d1e3867f7..000000000
--- a/Library/Homebrew/test/language_python_test.rb
+++ /dev/null
@@ -1,99 +0,0 @@
-require "testing_env"
-require "language/python"
-require "resource"
-
-class LanguagePythonTests < Homebrew::TestCase
-  def setup
-    @dir = Pathname.new(mktmpdir)
-    resource = stub("resource", stage: true)
-    formula_bin = @dir/"formula_bin"
-    @formula = mock("formula") do
-      stubs(:resource).returns(resource)
-      stubs(:bin).returns(formula_bin)
-    end
-    @venv = Language::Python::Virtualenv::Virtualenv.new(@formula, @dir, "python")
-  end
-
-  def teardown
-    FileUtils.rm_rf @dir
-  end
-
-  def test_virtualenv_creation
-    @formula.expects(:resource).with("homebrew-virtualenv").returns(
-      mock("resource", stage: true)
-    )
-    @venv.create
-  end
-
-  # or at least doesn't crash the second time
-  def test_virtualenv_creation_is_idempotent
-    @formula.expects(:resource).with("homebrew-virtualenv").returns(
-      mock("resource", stage: true)
-    )
-    @venv.create
-    FileUtils.mkdir_p @dir/"bin"
-    FileUtils.touch @dir/"bin/python"
-    @venv.create
-    FileUtils.rm @dir/"bin/python"
-  end
-
-  def test_pip_install_accepts_string
-    @formula.expects(:system).returns(true).with do |*params|
-      params.first == @dir/"bin/pip" && params.last == "foo"
-    end
-    @venv.pip_install "foo"
-  end
-
-  def test_pip_install_accepts_multiline_string
-    @formula.expects(:system).returns(true).with do |*params|
-      params.first == @dir/"bin/pip" && params[-2..-1] == ["foo", "bar"]
-    end
-    @venv.pip_install <<-EOS.undent
-      foo
-      bar
-    EOS
-  end
-
-  def test_pip_install_accepts_array
-    @formula.expects(:system).returns(true).with do |*params|
-      params.first == @dir/"bin/pip" && params.last == "foo"
-    end
-    @formula.expects(:system).returns(true).with do |*params|
-      params.first == @dir/"bin/pip" && params.last == "bar"
-    end
-    @venv.pip_install ["foo", "bar"]
-  end
-
-  def test_pip_install_accepts_resource
-    res = Resource.new "test"
-    res.expects(:stage).yields(nil)
-    @formula.expects(:system).returns(true).with do |*params|
-      params.first == @dir/"bin/pip" && params.last == Pathname.pwd
-    end
-    @venv.pip_install res
-  end
-
-  def test_pip_install_and_link_links_scripts
-    bin = @dir/"bin"
-    bin.mkpath
-    dest = @formula.bin
-
-    refute_predicate bin/"kilroy", :exist?
-    refute_predicate dest/"kilroy", :exist?
-
-    FileUtils.touch bin/"irrelevant"
-    bin_before = Dir[bin/"*"]
-    FileUtils.touch bin/"kilroy"
-    bin_after = Dir[bin/"*"]
-    @venv.expects(:pip_install).with("foo")
-    Dir.expects(:[]).twice.returns(bin_before, bin_after)
-
-    @venv.pip_install_and_link "foo"
-
-    assert_predicate bin/"kilroy", :exist?
-    assert_predicate dest/"kilroy", :exist?
-    assert_predicate dest/"kilroy", :symlink?
-    assert_equal((bin/"kilroy").realpath, (dest/"kilroy").realpath)
-    refute_predicate dest/"irrelevant", :exist?
-  end
-end
diff --git a/Library/Homebrew/test/leaves_test.rb b/Library/Homebrew/test/leaves_test.rb
deleted file mode 100644
index f73fba1ea..000000000
--- a/Library/Homebrew/test/leaves_test.rb
+++ /dev/null
@@ -1,15 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestLeaves < IntegrationCommandTestCase
-  def test_leaves
-    setup_test_formula "foo"
-    setup_test_formula "bar"
-    assert_equal "", cmd("leaves")
-
-    (HOMEBREW_CELLAR/"foo/0.1/somedir").mkpath
-    assert_equal "foo", cmd("leaves")
-
-    (HOMEBREW_CELLAR/"bar/0.1/somedir").mkpath
-    assert_equal "bar", cmd("leaves")
-  end
-end
diff --git a/Library/Homebrew/test/link_test.rb b/Library/Homebrew/test/link_test.rb
deleted file mode 100644
index 062caa0c0..000000000
--- a/Library/Homebrew/test/link_test.rb
+++ /dev/null
@@ -1,23 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestLink < IntegrationCommandTestCase
-  def test_link
-    assert_match "This command requires a keg argument", cmd_fail("link")
-
-    setup_test_formula "testball1"
-    cmd("install", "testball1")
-    cmd("link", "testball1")
-
-    cmd("unlink", "testball1")
-    assert_match "Would link", cmd("link", "--dry-run", "testball1")
-    assert_match "Would remove",
-      cmd("link", "--dry-run", "--overwrite", "testball1")
-    assert_match "Linking", cmd("link", "testball1")
-
-    setup_test_formula "testball2", <<-EOS.undent
-      keg_only "just because"
-    EOS
-    cmd("install", "testball2")
-    assert_match "testball2 is keg-only", cmd("link", "testball2")
-  end
-end
diff --git a/Library/Homebrew/test/linkapps_test.rb b/Library/Homebrew/test/linkapps_test.rb
deleted file mode 100644
index 4c5b8ec13..000000000
--- a/Library/Homebrew/test/linkapps_test.rb
+++ /dev/null
@@ -1,15 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestLinkapps < IntegrationCommandTestCase
-  def test_linkapps
-    home_dir = Pathname.new(mktmpdir)
-    (home_dir/"Applications").mkpath
-
-    setup_test_formula "testball"
-
-    source_dir = HOMEBREW_CELLAR/"testball/0.1/TestBall.app"
-    source_dir.mkpath
-    assert_match "Linking: #{source_dir}",
-      cmd("linkapps", "--local", "HOME" => home_dir)
-  end
-end
diff --git a/Library/Homebrew/test/list_test.rb b/Library/Homebrew/test/list_test.rb
deleted file mode 100644
index 3c691e3ad..000000000
--- a/Library/Homebrew/test/list_test.rb
+++ /dev/null
@@ -1,13 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestList < IntegrationCommandTestCase
-  def test_list
-    formulae = %w[bar foo qux]
-    formulae.each do |f|
-      (HOMEBREW_CELLAR/"#{f}/1.0/somedir").mkpath
-    end
-
-    assert_equal formulae.join("\n"),
-                 cmd("list")
-  end
-end
diff --git a/Library/Homebrew/test/log_formula_test.rb b/Library/Homebrew/test/log_formula_test.rb
deleted file mode 100644
index bb6a1f661..000000000
--- a/Library/Homebrew/test/log_formula_test.rb
+++ /dev/null
@@ -1,27 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestLogFormula < IntegrationCommandTestCase
-  def test_log_formula
-    core_tap = CoreTap.new
-    setup_test_formula "testball"
-
-    core_tap.path.cd do
-      shutup do
-        system "git", "init"
-        system "git", "add", "--all"
-        system "git", "commit", "-m", "This is a test commit for Testball"
-      end
-    end
-
-    core_tap_url = "file://#{core_tap.path}"
-    shallow_tap = Tap.fetch("homebrew", "shallow")
-    shutup do
-      system "git", "clone", "--depth=1", core_tap_url, shallow_tap.path
-    end
-
-    assert_match "This is a test commit for Testball",
-                 cmd("log", "#{shallow_tap}/testball")
-    assert_predicate shallow_tap.path/".git/shallow", :exist?,
-                     "A shallow clone should have been created."
-  end
-end
diff --git a/Library/Homebrew/test/log_test.rb b/Library/Homebrew/test/log_test.rb
deleted file mode 100644
index b2e150ccd..000000000
--- a/Library/Homebrew/test/log_test.rb
+++ /dev/null
@@ -1,13 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestLog < IntegrationCommandTestCase
-  def test_log
-    FileUtils.cd HOMEBREW_REPOSITORY do
-      shutup do
-        system "git", "init"
-        system "git", "commit", "--allow-empty", "-m", "This is a test commit"
-      end
-    end
-    assert_match "This is a test commit", cmd("log")
-  end
-end
diff --git a/Library/Homebrew/test/migrate_test.rb b/Library/Homebrew/test/migrate_test.rb
deleted file mode 100644
index 17929d038..000000000
--- a/Library/Homebrew/test/migrate_test.rb
+++ /dev/null
@@ -1,18 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestMigrate < IntegrationCommandTestCase
-  def test_migrate
-    setup_test_formula "testball1"
-    setup_test_formula "testball2"
-    assert_match "Invalid usage", cmd_fail("migrate")
-    assert_match "No available formula with the name \"testball\"",
-      cmd_fail("migrate", "testball")
-    assert_match "testball1 doesn't replace any formula",
-      cmd_fail("migrate", "testball1")
-
-    install_and_rename_coretap_formula "testball1", "testball2"
-    assert_match "Migrating testball1 to testball2", cmd("migrate", "testball1")
-    (HOMEBREW_CELLAR/"testball1").unlink
-    assert_match "Error: No such keg", cmd_fail("migrate", "testball1")
-  end
-end
diff --git a/Library/Homebrew/test/migrator_spec.rb b/Library/Homebrew/test/migrator_spec.rb
new file mode 100644
index 000000000..90ee9d8ff
--- /dev/null
+++ b/Library/Homebrew/test/migrator_spec.rb
@@ -0,0 +1,264 @@
+require "migrator"
+require "test/support/fixtures/testball"
+require "tab"
+require "keg"
+
+describe Migrator do
+  subject { described_class.new(new_formula) }
+
+  let(:new_formula) { Testball.new("newname") }
+  let(:old_formula) { Testball.new("oldname") }
+
+  let(:new_keg_record) { HOMEBREW_CELLAR/"newname/0.1" }
+  let(:old_keg_record) { HOMEBREW_CELLAR/"oldname/0.1" }
+
+  let(:old_tab) { Tab.empty }
+
+  let(:keg) { Keg.new(old_keg_record) }
+  let(:old_pin) { HOMEBREW_PINNED_KEGS/"oldname" }
+
+  before(:each) do |example|
+    allow(new_formula).to receive(:oldname).and_return("oldname")
+
+    # do not create directories for error tests
+    next if example.metadata[:description].start_with?("raises an error")
+
+    (old_keg_record/"bin").mkpath
+
+    %w[inside bindir].each do |file|
+      FileUtils.touch old_keg_record/"bin/#{file}"
+    end
+
+    old_tab.tabfile = HOMEBREW_CELLAR/"oldname/0.1/INSTALL_RECEIPT.json"
+    old_tab.source["path"] = "/oldname"
+    old_tab.write
+
+    keg.link
+    keg.optlink
+
+    old_pin.make_relative_symlink old_keg_record
+
+    subject # needs to be evaluated eagerly
+
+    (HOMEBREW_PREFIX/"bin").mkpath
+  end
+
+  after(:each) do
+    if !old_keg_record.parent.symlink? && old_keg_record.directory?
+      keg.unlink
+    end
+
+    if new_keg_record.directory?
+      new_keg = Keg.new(new_keg_record)
+      new_keg.unlink
+    end
+  end
+
+  describe "::new" do
+    it "raises an error if there is no old name" do
+      expect {
+        described_class.new(old_formula)
+      }.to raise_error(Migrator::MigratorNoOldnameError)
+    end
+
+    it "raises an error if there is no old path" do
+      expect {
+        described_class.new(new_formula)
+      }.to raise_error(Migrator::MigratorNoOldpathError)
+    end
+
+    it "raises an error if the Taps differ" do
+      keg = HOMEBREW_CELLAR/"oldname/0.1"
+      keg.mkpath
+      tab = Tab.empty
+      tab.tabfile = HOMEBREW_CELLAR/"oldname/0.1/INSTALL_RECEIPT.json"
+      tab.source["tap"] = "homebrew/core"
+      tab.write
+
+      expect {
+        described_class.new(new_formula)
+      }.to raise_error(Migrator::MigratorDifferentTapsError)
+    end
+  end
+
+  specify "#move_to_new_directory" do
+    keg.unlink
+    shutup do
+      subject.move_to_new_directory
+    end
+
+    expect(new_keg_record).to be_a_directory
+    expect(new_keg_record/"bin").to be_a_directory
+    expect(new_keg_record/"bin/inside").to be_a_file
+    expect(new_keg_record/"bin/bindir").to be_a_file
+    expect(old_keg_record).not_to be_a_directory
+  end
+
+  specify "#backup_oldname_cellar" do
+    old_keg_record.parent.rmtree
+    (new_keg_record/"bin").mkpath
+
+    subject.backup_oldname_cellar
+
+    expect(old_keg_record/"bin").to be_a_directory
+    expect(old_keg_record/"bin").to be_a_directory
+  end
+
+  specify "#repin" do
+    (new_keg_record/"bin").mkpath
+    expected_relative = new_keg_record.relative_path_from HOMEBREW_PINNED_KEGS
+
+    subject.repin
+
+    expect(subject.new_pin_record).to be_a_symlink
+    expect(subject.new_pin_record.readlink).to eq(expected_relative)
+    expect(subject.old_pin_record).not_to exist
+  end
+
+  specify "#unlink_oldname" do
+    expect(HOMEBREW_LINKED_KEGS.children.count).to eq(1)
+    expect((HOMEBREW_PREFIX/"opt").children.count).to eq(1)
+
+    shutup do
+      subject.unlink_oldname
+    end
+
+    expect(HOMEBREW_LINKED_KEGS).not_to exist
+    expect(HOMEBREW_LIBRARY/"bin").not_to exist
+  end
+
+  specify "#link_newname" do
+    keg.unlink
+    keg.uninstall
+
+    (new_keg_record/"bin").mkpath
+    %w[inside bindir].each do |file|
+      FileUtils.touch new_keg_record/"bin"/file
+    end
+
+    shutup do
+      subject.link_newname
+    end
+
+    expect(HOMEBREW_LINKED_KEGS.children.count).to eq(1)
+    expect((HOMEBREW_PREFIX/"opt").children.count).to eq(1)
+  end
+
+  specify "#link_oldname_opt" do
+    new_keg_record.mkpath
+    subject.link_oldname_opt
+    expect((HOMEBREW_PREFIX/"opt/oldname").realpath).to eq(new_keg_record.realpath)
+  end
+
+  specify "#link_oldname_cellar" do
+    (new_keg_record/"bin").mkpath
+    keg.unlink
+    keg.uninstall
+    subject.link_oldname_cellar
+    expect((HOMEBREW_CELLAR/"oldname").realpath).to eq(new_keg_record.parent.realpath)
+  end
+
+  specify "#update_tabs" do
+    (new_keg_record/"bin").mkpath
+    tab = Tab.empty
+    tab.tabfile = HOMEBREW_CELLAR/"newname/0.1/INSTALL_RECEIPT.json"
+    tab.source["path"] = "/path/that/must/be/changed/by/update_tabs"
+    tab.write
+    subject.update_tabs
+    expect(Tab.for_keg(new_keg_record).source["path"]).to eq(new_formula.path.to_s)
+  end
+
+  specify "#migrate" do
+    tab = Tab.empty
+    tab.tabfile = HOMEBREW_CELLAR/"oldname/0.1/INSTALL_RECEIPT.json"
+    tab.source["path"] = old_formula.path.to_s
+    tab.write
+
+    shutup do
+      subject.migrate
+    end
+
+    expect(new_keg_record).to exist
+    expect(old_keg_record.parent).to be_a_symlink
+    expect(HOMEBREW_LINKED_KEGS/"oldname").not_to exist
+    expect((HOMEBREW_LINKED_KEGS/"newname").realpath).to eq(new_keg_record.realpath)
+    expect(old_keg_record.realpath).to eq(new_keg_record.realpath)
+    expect((HOMEBREW_PREFIX/"opt/oldname").realpath).to eq(new_keg_record.realpath)
+    expect((HOMEBREW_CELLAR/"oldname").realpath).to eq(new_keg_record.parent.realpath)
+    expect((HOMEBREW_PINNED_KEGS/"newname").realpath).to eq(new_keg_record.realpath)
+    expect(Tab.for_keg(new_keg_record).source["path"]).to eq(new_formula.path.to_s)
+  end
+
+  specify "#unlinik_oldname_opt" do
+    new_keg_record.mkpath
+    old_opt_record = HOMEBREW_PREFIX/"opt/oldname"
+    old_opt_record.unlink if old_opt_record.symlink?
+    old_opt_record.make_relative_symlink(new_keg_record)
+    subject.unlink_oldname_opt
+    expect(old_opt_record).not_to be_a_symlink
+  end
+
+  specify "#unlink_oldname_cellar" do
+    new_keg_record.mkpath
+    keg.unlink
+    keg.uninstall
+    old_keg_record.parent.make_relative_symlink(new_keg_record.parent)
+    subject.unlink_oldname_cellar
+    expect(old_keg_record.parent).not_to be_a_symlink
+  end
+
+  specify "#backup_oldname_cellar" do
+    (new_keg_record/"bin").mkpath
+    keg.unlink
+    keg.uninstall
+    subject.backup_oldname_cellar
+    expect(old_keg_record.subdirs).not_to be_empty
+  end
+
+  specify "#backup_old_tabs" do
+    tab = Tab.empty
+    tab.tabfile = HOMEBREW_CELLAR/"oldname/0.1/INSTALL_RECEIPT.json"
+    tab.source["path"] = "/should/be/the/same"
+    tab.write
+    migrator = Migrator.new(new_formula)
+    tab.tabfile.delete
+    migrator.backup_old_tabs
+    expect(Tab.for_keg(old_keg_record).source["path"]).to eq("/should/be/the/same")
+  end
+
+  describe "#backup_oldname" do
+    after(:each) do
+      expect(old_keg_record.parent).to be_a_directory
+      expect(old_keg_record.parent.subdirs).not_to be_empty
+      expect(HOMEBREW_LINKED_KEGS/"oldname").to exist
+      expect(HOMEBREW_PREFIX/"opt/oldname").to exist
+      expect(HOMEBREW_PINNED_KEGS/"oldname").to be_a_symlink
+      expect(keg).to be_linked
+    end
+
+    context "when cellar exists" do
+      it "backs up the old name" do
+        subject.backup_oldname
+      end
+    end
+
+    context "when cellar is removed" do
+      it "backs up the old name" do
+        (new_keg_record/"bin").mkpath
+        keg.unlink
+        keg.uninstall
+        subject.backup_oldname
+      end
+    end
+
+    context "when cellar is linked" do
+      it "backs up the old name" do
+        (new_keg_record/"bin").mkpath
+        keg.unlink
+        keg.uninstall
+        old_keg_record.parent.make_relative_symlink(new_keg_record.parent)
+        subject.backup_oldname
+      end
+    end
+  end
+end
diff --git a/Library/Homebrew/test/migrator_test.rb b/Library/Homebrew/test/migrator_test.rb
deleted file mode 100644
index 8a2b6ad63..000000000
--- a/Library/Homebrew/test/migrator_test.rb
+++ /dev/null
@@ -1,264 +0,0 @@
-require "testing_env"
-require "migrator"
-require "test/support/fixtures/testball"
-require "tab"
-require "keg"
-
-class Formula
-  attr_writer :oldname
-end
-
-class MigratorErrorsTests < Homebrew::TestCase
-  def setup
-    @new_f = Testball.new("newname")
-    @new_f.oldname = "oldname"
-    @old_f = Testball.new("oldname")
-  end
-
-  def test_no_oldname
-    assert_raises(Migrator::MigratorNoOldnameError) { Migrator.new(@old_f) }
-  end
-
-  def test_no_oldpath
-    assert_raises(Migrator::MigratorNoOldpathError) { Migrator.new(@new_f) }
-  end
-
-  def test_different_taps
-    keg = HOMEBREW_CELLAR/"oldname/0.1"
-    keg.mkpath
-    tab = Tab.empty
-    tab.tabfile = HOMEBREW_CELLAR/"oldname/0.1/INSTALL_RECEIPT.json"
-    tab.source["tap"] = "homebrew/core"
-    tab.write
-    assert_raises(Migrator::MigratorDifferentTapsError) { Migrator.new(@new_f) }
-  ensure
-    keg.parent.rmtree
-  end
-end
-
-class MigratorTests < Homebrew::TestCase
-  include FileUtils
-
-  def setup
-    @new_f = Testball.new("newname")
-    @new_f.oldname = "oldname"
-
-    @old_f = Testball.new("oldname")
-
-    @old_keg_record = HOMEBREW_CELLAR/"oldname/0.1"
-    @old_keg_record.join("bin").mkpath
-    @new_keg_record = HOMEBREW_CELLAR/"newname/0.1"
-
-    %w[inside bindir].each { |file| touch @old_keg_record.join("bin", file) }
-
-    @old_tab = Tab.empty
-    @old_tab.tabfile = HOMEBREW_CELLAR/"oldname/0.1/INSTALL_RECEIPT.json"
-    @old_tab.source["path"] = "/oldname"
-    @old_tab.write
-
-    @keg = Keg.new(@old_keg_record)
-    @keg.link
-    @keg.optlink
-
-    @old_pin = HOMEBREW_PINNED_KEGS/"oldname"
-    @old_pin.make_relative_symlink @old_keg_record
-
-    @migrator = Migrator.new(@new_f)
-
-    mkpath HOMEBREW_PREFIX/"bin"
-  end
-
-  def teardown
-    @old_pin.unlink if @old_pin.symlink?
-
-    if @old_keg_record.parent.symlink?
-      @old_keg_record.parent.unlink
-    elsif @old_keg_record.directory?
-      @keg.unlink
-      @keg.uninstall
-    end
-
-    if @new_keg_record.directory?
-      new_keg = Keg.new(@new_keg_record)
-      new_keg.unlink
-      new_keg.uninstall
-    end
-
-    @old_keg_record.parent.rmtree if @old_keg_record.parent.directory?
-    @new_keg_record.parent.rmtree if @new_keg_record.parent.directory?
-
-    rmtree HOMEBREW_PREFIX/"bin"
-    rmtree HOMEBREW_PREFIX/"opt" if (HOMEBREW_PREFIX/"opt").directory?
-    # What to do with pin?
-    @new_f.unpin
-
-    HOMEBREW_LOCK_DIR.children.each(&:unlink)
-  end
-
-  def test_move_cellar
-    @keg.unlink
-    shutup { @migrator.move_to_new_directory }
-    assert_predicate @new_keg_record, :directory?
-    assert_predicate @new_keg_record/"bin", :directory?
-    assert_predicate @new_keg_record/"bin/inside", :file?
-    assert_predicate @new_keg_record/"bin/bindir", :file?
-    refute_predicate @old_keg_record, :directory?
-  end
-
-  def test_backup_cellar
-    @old_keg_record.parent.rmtree
-    @new_keg_record.join("bin").mkpath
-
-    @migrator.backup_oldname_cellar
-
-    assert_predicate @old_keg_record, :directory?
-    assert_predicate @old_keg_record/"bin", :directory?
-  end
-
-  def test_repin
-    @new_keg_record.join("bin").mkpath
-    expected_relative = @new_keg_record.relative_path_from HOMEBREW_PINNED_KEGS
-
-    @migrator.repin
-
-    assert_predicate @migrator.new_pin_record, :symlink?
-    assert_equal expected_relative, @migrator.new_pin_record.readlink
-    refute_predicate @migrator.old_pin_record, :exist?
-  end
-
-  def test_unlink_oldname
-    assert_equal 1, HOMEBREW_LINKED_KEGS.children.size
-    assert_equal 1, (HOMEBREW_PREFIX/"opt").children.size
-
-    shutup { @migrator.unlink_oldname }
-
-    refute_predicate HOMEBREW_LINKED_KEGS, :exist?
-    refute_predicate HOMEBREW_LIBRARY/"bin", :exist?
-  end
-
-  def test_link_newname
-    @keg.unlink
-    @keg.uninstall
-    @new_keg_record.join("bin").mkpath
-    %w[inside bindir].each { |file| touch @new_keg_record.join("bin", file) }
-
-    shutup { @migrator.link_newname }
-
-    assert_equal 1, HOMEBREW_LINKED_KEGS.children.size
-    assert_equal 1, (HOMEBREW_PREFIX/"opt").children.size
-  end
-
-  def test_link_oldname_opt
-    @new_keg_record.mkpath
-    @migrator.link_oldname_opt
-    assert_equal @new_keg_record.realpath, (HOMEBREW_PREFIX/"opt/oldname").realpath
-  end
-
-  def test_link_oldname_cellar
-    @new_keg_record.join("bin").mkpath
-    @keg.unlink
-    @keg.uninstall
-    @migrator.link_oldname_cellar
-    assert_equal @new_keg_record.parent.realpath, (HOMEBREW_CELLAR/"oldname").realpath
-  end
-
-  def test_update_tabs
-    @new_keg_record.join("bin").mkpath
-    tab = Tab.empty
-    tab.tabfile = HOMEBREW_CELLAR/"newname/0.1/INSTALL_RECEIPT.json"
-    tab.source["path"] = "/path/that/must/be/changed/by/update_tabs"
-    tab.write
-    @migrator.update_tabs
-    assert_equal @new_f.path.to_s, Tab.for_keg(@new_keg_record).source["path"]
-  end
-
-  def test_migrate
-    tab = Tab.empty
-    tab.tabfile = HOMEBREW_CELLAR/"oldname/0.1/INSTALL_RECEIPT.json"
-    tab.source["path"] = @old_f.path.to_s
-    tab.write
-
-    shutup { @migrator.migrate }
-
-    assert_predicate @new_keg_record, :exist?
-    assert_predicate @old_keg_record.parent, :symlink?
-    refute_predicate HOMEBREW_LINKED_KEGS/"oldname", :exist?
-    assert_equal @new_keg_record.realpath, (HOMEBREW_LINKED_KEGS/"newname").realpath
-    assert_equal @new_keg_record.realpath, @old_keg_record.realpath
-    assert_equal @new_keg_record.realpath, (HOMEBREW_PREFIX/"opt/oldname").realpath
-    assert_equal @new_keg_record.parent.realpath, (HOMEBREW_CELLAR/"oldname").realpath
-    assert_equal @new_keg_record.realpath, (HOMEBREW_PINNED_KEGS/"newname").realpath
-    assert_equal @new_f.path.to_s, Tab.for_keg(@new_keg_record).source["path"]
-  end
-
-  def test_unlinik_oldname_opt
-    @new_keg_record.mkpath
-    old_opt_record = HOMEBREW_PREFIX/"opt/oldname"
-    old_opt_record.unlink if old_opt_record.symlink?
-    old_opt_record.make_relative_symlink(@new_keg_record)
-    @migrator.unlink_oldname_opt
-    refute_predicate old_opt_record, :symlink?
-  end
-
-  def test_unlink_oldname_cellar
-    @new_keg_record.mkpath
-    @keg.unlink
-    @keg.uninstall
-    @old_keg_record.parent.make_relative_symlink(@new_keg_record.parent)
-    @migrator.unlink_oldname_cellar
-    refute_predicate @old_keg_record.parent, :symlink?
-  end
-
-  def test_backup_oldname_cellar
-    @new_keg_record.join("bin").mkpath
-    @keg.unlink
-    @keg.uninstall
-    @migrator.backup_oldname_cellar
-    refute_predicate @old_keg_record.subdirs, :empty?
-  end
-
-  def test_backup_old_tabs
-    tab = Tab.empty
-    tab.tabfile = HOMEBREW_CELLAR/"oldname/0.1/INSTALL_RECEIPT.json"
-    tab.source["path"] = "/should/be/the/same"
-    tab.write
-    migrator = Migrator.new(@new_f)
-    tab.tabfile.delete
-    migrator.backup_old_tabs
-    assert_equal "/should/be/the/same", Tab.for_keg(@old_keg_record).source["path"]
-  end
-
-  # Backup tests are divided into three groups: when oldname Cellar is deleted
-  # and when it still exists and when it's a symlink
-
-  def check_after_backup
-    assert_predicate @old_keg_record.parent, :directory?
-    refute_predicate @old_keg_record.parent.subdirs, :empty?
-    assert_predicate HOMEBREW_LINKED_KEGS/"oldname", :exist?
-    assert_predicate HOMEBREW_PREFIX/"opt/oldname", :exist?
-    assert_predicate HOMEBREW_PINNED_KEGS/"oldname", :symlink?
-    assert_predicate @keg, :linked?
-  end
-
-  def test_backup_cellar_exist
-    @migrator.backup_oldname
-    check_after_backup
-  end
-
-  def test_backup_cellar_removed
-    @new_keg_record.join("bin").mkpath
-    @keg.unlink
-    @keg.uninstall
-    @migrator.backup_oldname
-    check_after_backup
-  end
-
-  def test_backup_cellar_linked
-    @new_keg_record.join("bin").mkpath
-    @keg.unlink
-    @keg.uninstall
-    @old_keg_record.parent.make_relative_symlink(@new_keg_record.parent)
-    @migrator.backup_oldname
-    check_after_backup
-  end
-end
diff --git a/Library/Homebrew/test/missing_test.rb b/Library/Homebrew/test/missing_test.rb
deleted file mode 100644
index 4f20d8a7a..000000000
--- a/Library/Homebrew/test/missing_test.rb
+++ /dev/null
@@ -1,34 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestMissing < IntegrationCommandTestCase
-  def setup
-    super
-
-    setup_test_formula "foo"
-    setup_test_formula "bar"
-  end
-
-  def make_prefix(name)
-    (HOMEBREW_CELLAR/name/"1.0").mkpath
-  end
-
-  def test_missing_missing
-    make_prefix "bar"
-
-    assert_match "foo", cmd("missing")
-  end
-
-  def test_missing_not_missing
-    make_prefix "foo"
-    make_prefix "bar"
-
-    assert_empty cmd("missing")
-  end
-
-  def test_missing_hide
-    make_prefix "foo"
-    make_prefix "bar"
-
-    assert_match "foo", cmd("missing", "--hide=foo")
-  end
-end
diff --git a/Library/Homebrew/test/mpi_requirement_spec.rb b/Library/Homebrew/test/mpi_requirement_spec.rb
new file mode 100644
index 000000000..f32b27993
--- /dev/null
+++ b/Library/Homebrew/test/mpi_requirement_spec.rb
@@ -0,0 +1,14 @@
+require "requirements/mpi_requirement"
+
+describe MPIRequirement do
+  describe "::new" do
+    subject { described_class.new(*(wrappers + tags)) }
+    let(:wrappers) { [:cc, :cxx, :f77] }
+    let(:tags) { [:optional, "some-other-tag"] }
+
+    it "untangles wrappers and tags" do
+      expect(subject.lang_list).to eq(wrappers)
+      expect(subject.tags).to eq(tags)
+    end
+  end
+end
diff --git a/Library/Homebrew/test/mpi_requirement_test.rb b/Library/Homebrew/test/mpi_requirement_test.rb
deleted file mode 100644
index e0f97e8ee..000000000
--- a/Library/Homebrew/test/mpi_requirement_test.rb
+++ /dev/null
@@ -1,12 +0,0 @@
-require "testing_env"
-require "requirements/mpi_requirement"
-
-class MPIRequirementTests < Homebrew::TestCase
-  def test_initialize_untangles_tags_and_wrapper_symbols
-    wrappers = [:cc, :cxx, :f77]
-    tags = [:optional, "some-other-tag"]
-    dep = MPIRequirement.new(*wrappers + tags)
-    assert_equal wrappers, dep.lang_list
-    assert_equal tags, dep.tags
-  end
-end
diff --git a/Library/Homebrew/test/options_spec.rb b/Library/Homebrew/test/options_spec.rb
new file mode 100644
index 000000000..a05bb139e
--- /dev/null
+++ b/Library/Homebrew/test/options_spec.rb
@@ -0,0 +1,148 @@
+require "options"
+
+describe Option do
+  subject { described_class.new("foo") }
+
+  specify "#to_s" do
+    expect(subject.to_s).to eq("--foo")
+  end
+
+  specify "equality" do
+    foo = Option.new("foo")
+    bar = Option.new("bar")
+    expect(subject).to eq(foo)
+    expect(subject).not_to eq(bar)
+    expect(subject).to eql(foo)
+    expect(subject).not_to eql(bar)
+  end
+
+  specify "#description" do
+    expect(subject.description).to be_empty
+    expect(Option.new("foo", "foo").description).to eq("foo")
+  end
+
+  specify "#inspect" do
+    expect(subject.inspect).to eq("#<Option: \"--foo\">")
+  end
+end
+
+describe DeprecatedOption do
+  subject { described_class.new("foo", "bar") }
+
+  specify "#old" do
+    expect(subject.old).to eq("foo")
+  end
+
+  specify "#old_flag" do
+    expect(subject.old_flag).to eq("--foo")
+  end
+
+  specify "#current" do
+    expect(subject.current).to eq("bar")
+  end
+
+  specify "#current_flag" do
+    expect(subject.current_flag).to eq("--bar")
+  end
+
+  specify "equality" do
+    foobar = DeprecatedOption.new("foo", "bar")
+    boofar = DeprecatedOption.new("boo", "far")
+    expect(foobar).to eq(subject)
+    expect(subject).to eq(foobar)
+    expect(boofar).not_to eq(subject)
+    expect(subject).not_to eq(boofar)
+  end
+end
+
+describe Options do
+  it "removes duplicate options" do
+    subject << Option.new("foo")
+    subject << Option.new("foo")
+    expect(subject).to include("--foo")
+    expect(subject.count).to eq(1)
+  end
+
+  it "preserves  existing member when adding a duplicate" do
+    a = Option.new("foo", "bar")
+    b = Option.new("foo", "qux")
+    subject << a << b
+    expect(subject.count).to eq(1)
+    expect(subject.first).to be(a)
+    expect(subject.first.description).to eq(a.description)
+  end
+
+  specify "#include?" do
+    subject << Option.new("foo")
+    expect(subject).to include("--foo")
+    expect(subject).to include("foo")
+    expect(subject).to include(Option.new("foo"))
+  end
+
+  describe "#+" do
+    it "returns options" do
+      expect(subject + Options.new).to be_an_instance_of(Options)
+    end
+  end
+
+  describe "#-" do
+    it "returns options" do
+      expect(subject - Options.new).to be_an_instance_of(Options)
+    end
+  end
+
+  specify "#&" do
+    foo, bar, baz = %w[foo bar baz].map { |o| Option.new(o) }
+    options = Options.new << foo << bar
+    subject << foo << baz
+    expect((subject & options).to_a).to eq([foo])
+  end
+
+  specify "#|" do
+    foo, bar, baz = %w[foo bar baz].map { |o| Option.new(o) }
+    options = Options.new << foo << bar
+    subject << foo << baz
+    expect((subject | options).sort).to eq([foo, bar, baz].sort)
+  end
+
+  specify "#*" do
+    subject << Option.new("aa") << Option.new("bb") << Option.new("cc")
+    expect((subject * "XX").split("XX").sort).to eq(%w[--aa --bb --cc])
+  end
+
+  describe "<<" do
+    it "returns itself" do
+      expect(subject << Option.new("foo")).to be subject
+    end
+  end
+
+  specify "#as_flags" do
+    subject << Option.new("foo")
+    expect(subject.as_flags).to eq(%w[--foo])
+  end
+
+  specify "#to_a" do
+    option = Option.new("foo")
+    subject << option
+    expect(subject.to_a).to eq([option])
+  end
+
+  specify "#to_ary" do
+    option = Option.new("foo")
+    subject << option
+    expect(subject.to_ary).to eq([option])
+  end
+
+  specify "::create_with_array" do
+    array = %w[--foo --bar]
+    option1 = Option.new("foo")
+    option2 = Option.new("bar")
+    expect(Options.create(array).sort).to eq([option1, option2].sort)
+  end
+
+  specify "#inspect" do
+    expect(subject.inspect).to eq("#<Options: []>")
+    subject << Option.new("foo")
+    expect(subject.inspect).to eq("#<Options: [#<Option: \"--foo\">]>")
+  end
+end
diff --git a/Library/Homebrew/test/options_test.rb b/Library/Homebrew/test/options_test.rb
deleted file mode 100644
index e7189a604..000000000
--- a/Library/Homebrew/test/options_test.rb
+++ /dev/null
@@ -1,157 +0,0 @@
-require "testing_env"
-require "options"
-require "testing_env"
-
-class IntegrationCommandTestOptions < IntegrationCommandTestCase
-  def test_options
-    setup_test_formula "testball", <<-EOS.undent
-      depends_on "bar" => :recommended
-    EOS
-
-    assert_equal "--with-foo\n\tBuild with foo\n--without-bar\n\tBuild without bar support",
-      cmd_output("options", "testball").chomp
-  end
-end
-
-class OptionTests < Homebrew::TestCase
-  def setup
-    @option = Option.new("foo")
-  end
-
-  def test_to_s
-    assert_equal "--foo", @option.to_s
-  end
-
-  def test_equality
-    foo = Option.new("foo")
-    bar = Option.new("bar")
-    assert_equal foo, @option
-    refute_equal bar, @option
-    assert_eql @option, foo
-    refute_eql @option, bar
-  end
-
-  def test_description
-    assert_empty @option.description
-    assert_equal "foo", Option.new("foo", "foo").description
-  end
-
-  def test_inspect
-    assert_equal "#<Option: \"--foo\">", @option.inspect
-  end
-end
-
-class DeprecatedOptionTests < Homebrew::TestCase
-  def setup
-    @deprecated_option = DeprecatedOption.new("foo", "bar")
-  end
-
-  def test_old
-    assert_equal "foo", @deprecated_option.old
-    assert_equal "--foo", @deprecated_option.old_flag
-  end
-
-  def test_current
-    assert_equal "bar", @deprecated_option.current
-    assert_equal "--bar", @deprecated_option.current_flag
-  end
-
-  def test_equality
-    foobar = DeprecatedOption.new("foo", "bar")
-    boofar = DeprecatedOption.new("boo", "far")
-    assert_equal foobar, @deprecated_option
-    refute_equal boofar, @deprecated_option
-    assert_eql @deprecated_option, foobar
-    refute_eql @deprecated_option, boofar
-  end
-end
-
-class OptionsTests < Homebrew::TestCase
-  def setup
-    @options = Options.new
-  end
-
-  def test_no_duplicate_options
-    @options << Option.new("foo")
-    @options << Option.new("foo")
-    assert_includes @options, "--foo"
-    assert_equal 1, @options.count
-  end
-
-  def test_preserves_existing_member_when_pushing_duplicate
-    a = Option.new("foo", "bar")
-    b = Option.new("foo", "qux")
-    @options << a << b
-    assert_equal 1, @options.count
-    assert_same a, @options.first
-    assert_equal a.description, @options.first.description
-  end
-
-  def test_include
-    @options << Option.new("foo")
-    assert_includes @options, "--foo"
-    assert_includes @options, "foo"
-    assert_includes @options, Option.new("foo")
-  end
-
-  def test_union_returns_options
-    assert_instance_of Options, @options + Options.new
-  end
-
-  def test_difference_returns_options
-    assert_instance_of Options, @options - Options.new
-  end
-
-  def test_shovel_returns_self
-    assert_same @options, @options << Option.new("foo")
-  end
-
-  def test_as_flags
-    @options << Option.new("foo")
-    assert_equal %w[--foo], @options.as_flags
-  end
-
-  def test_to_a
-    option = Option.new("foo")
-    @options << option
-    assert_equal [option], @options.to_a
-  end
-
-  def test_to_ary
-    option = Option.new("foo")
-    @options << option
-    assert_equal [option], @options.to_ary
-  end
-
-  def test_intersection
-    foo, bar, baz = %w[foo bar baz].map { |o| Option.new(o) }
-    options = Options.new << foo << bar
-    @options << foo << baz
-    assert_equal [foo], (@options & options).to_a
-  end
-
-  def test_set_union
-    foo, bar, baz = %w[foo bar baz].map { |o| Option.new(o) }
-    options = Options.new << foo << bar
-    @options << foo << baz
-    assert_equal [foo, bar, baz].sort, (@options | options).sort
-  end
-
-  def test_times
-    @options << Option.new("aa") << Option.new("bb") << Option.new("cc")
-    assert_equal %w[--aa --bb --cc], (@options * "XX").split("XX").sort
-  end
-
-  def test_create_with_array
-    array = %w[--foo --bar]
-    option1 = Option.new("foo")
-    option2 = Option.new("bar")
-    assert_equal [option1, option2].sort, Options.create(array).sort
-  end
-
-  def test_inspect
-    assert_equal "#<Options: []>", @options.inspect
-    @options << Option.new("foo")
-    assert_equal "#<Options: [#<Option: \"--foo\">]>", @options.inspect
-  end
-end
diff --git a/Library/Homebrew/test/os/mac/blacklist_test.rb b/Library/Homebrew/test/os/mac/blacklist_test.rb
deleted file mode 100644
index 26dd84ed9..000000000
--- a/Library/Homebrew/test/os/mac/blacklist_test.rb
+++ /dev/null
@@ -1,12 +0,0 @@
-require "testing_env"
-require "blacklist"
-
-class OSMacBlacklistTests < Homebrew::TestCase
-  def assert_blacklisted(s)
-    assert blacklisted?(s), "'#{s}' should be blacklisted"
-  end
-
-  def test_xcode
-    %w[xcode Xcode].each { |s| assert_blacklisted s }
-  end
-end
diff --git a/Library/Homebrew/test/os/mac/bottle_collector_test.rb b/Library/Homebrew/test/os/mac/bottle_collector_test.rb
deleted file mode 100644
index 2f88050ae..000000000
--- a/Library/Homebrew/test/os/mac/bottle_collector_test.rb
+++ /dev/null
@@ -1,26 +0,0 @@
-require "testing_env"
-require "utils/bottles"
-
-class OSMacBottleCollectorTests < Homebrew::TestCase
-  def setup
-    @collector = Utils::Bottles::Collector.new
-  end
-
-  def checksum_for(tag)
-    @collector.fetch_checksum_for(tag)
-  end
-
-  def test_collector_finds_or_later_tags
-    @collector[:lion_or_later] = "foo"
-    assert_equal ["foo", :lion_or_later], checksum_for(:mountain_lion)
-    assert_nil checksum_for(:snow_leopard)
-  end
-
-  def test_collector_finds_altivec_tags
-    @collector[:tiger_altivec] = "foo"
-    assert_equal ["foo", :tiger_altivec], checksum_for(:tiger_g4)
-    assert_equal ["foo", :tiger_altivec], checksum_for(:tiger_g4e)
-    assert_equal ["foo", :tiger_altivec], checksum_for(:tiger_g5)
-    assert_nil checksum_for(:tiger_g3)
-  end
-end
diff --git a/Library/Homebrew/test/os/mac/bottle_tag_test.rb b/Library/Homebrew/test/os/mac/bottle_tag_test.rb
deleted file mode 100644
index 996bd4d53..000000000
--- a/Library/Homebrew/test/os/mac/bottle_tag_test.rb
+++ /dev/null
@@ -1,79 +0,0 @@
-require "testing_env"
-require "utils/bottles"
-
-class OSMacBottleTagTests < Homebrew::TestCase
-  def test_tag_tiger_ppc
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.4"))
-    Hardware::CPU.stubs(:type).returns(:ppc)
-    Hardware::CPU.stubs(:family).returns(:foo)
-    MacOS.stubs(:prefer_64_bit?).returns(false)
-    assert_equal :tiger_foo, Utils::Bottles.tag
-  end
-
-  def test_tag_tiger_intel
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.4"))
-    Hardware::CPU.stubs(:type).returns(:intel)
-    MacOS.stubs(:prefer_64_bit?).returns(false)
-    assert_equal :tiger, Utils::Bottles.tag
-  end
-
-  def test_tag_tiger_ppc_64
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.4"))
-    Hardware::CPU.stubs(:type).returns(:ppc)
-    Hardware::CPU.stubs(:family).returns(:g5)
-    MacOS.stubs(:prefer_64_bit?).returns(true)
-    assert_equal :tiger_g5_64, Utils::Bottles.tag
-  end
-
-  # Note that this will probably never be used
-  def test_tag_tiger_intel_64
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.4"))
-    Hardware::CPU.stubs(:type).returns(:intel)
-    MacOS.stubs(:prefer_64_bit?).returns(true)
-    assert_equal :tiger_64, Utils::Bottles.tag
-  end
-
-  def test_tag_leopard_intel
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.5"))
-    Hardware::CPU.stubs(:type).returns(:intel)
-    MacOS.stubs(:prefer_64_bit?).returns(false)
-    assert_equal :leopard, Utils::Bottles.tag
-  end
-
-  def test_tag_leopard_ppc_64
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.5"))
-    Hardware::CPU.stubs(:type).returns(:ppc)
-    Hardware::CPU.stubs(:family).returns(:g5)
-    MacOS.stubs(:prefer_64_bit?).returns(true)
-    assert_equal :leopard_g5_64, Utils::Bottles.tag
-  end
-
-  def test_tag_leopard_intel_64
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.5"))
-    Hardware::CPU.stubs(:type).returns(:intel)
-    MacOS.stubs(:prefer_64_bit?).returns(true)
-    assert_equal :leopard_64, Utils::Bottles.tag
-  end
-
-  def test_tag_snow_leopard_32
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.6"))
-    Hardware::CPU.stubs(:is_64_bit?).returns(false)
-    assert_equal :snow_leopard_32, Utils::Bottles.tag
-  end
-
-  def test_tag_snow_leopard_64
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.6"))
-    Hardware::CPU.stubs(:is_64_bit?).returns(true)
-    assert_equal :snow_leopard, Utils::Bottles.tag
-  end
-
-  def test_tag_lion
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.7"))
-    assert_equal :lion, Utils::Bottles.tag
-  end
-
-  def test_tag_mountain_lion
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.8"))
-    assert_equal :mountain_lion, Utils::Bottles.tag
-  end
-end
diff --git a/Library/Homebrew/test/os/mac/dependency_collector_spec.rb b/Library/Homebrew/test/os/mac/dependency_collector_spec.rb
new file mode 100644
index 000000000..21b15cd99
--- /dev/null
+++ b/Library/Homebrew/test/os/mac/dependency_collector_spec.rb
@@ -0,0 +1,50 @@
+require "dependency_collector"
+
+RSpec::Matchers.alias_matcher :need_tar_xz_dependency, :be_tar_needs_xz_dependency
+
+describe DependencyCollector do
+  after(:each) do
+    described_class.clear_cache
+  end
+
+  specify "#tar_needs_xz_dependency?" do
+    allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.9"))
+    expect(described_class).not_to need_tar_xz_dependency
+  end
+
+  specify "LD64 pre-Leopard dependency" do
+    allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.4"))
+    expect(subject.build(:ld64)).to eq(LD64Dependency.new)
+  end
+
+  specify "LD64 Leopard or newer dependency" do
+    allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.5"))
+    expect(subject.build(:ld64)).to be nil
+  end
+
+  specify "ant Mavericks or newer dependency" do
+    allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.9"))
+    subject.add ant: :build
+    expect(subject.deps.find { |dep| dep.name == "ant" }).to eq(Dependency.new("ant", [:build]))
+  end
+
+  specify "ant pre-Mavericks dependency" do
+    allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.7"))
+    subject.add ant: :build
+    expect(subject.deps.find { |dep| dep.name == "ant" }).to be nil
+  end
+
+  specify "Resource xz pre-Mavericks dependency" do
+    allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.8"))
+    resource = Resource.new
+    resource.url("http://example.com/foo.tar.xz")
+    expect(subject.add(resource)).to eq(Dependency.new("xz", [:build]))
+  end
+
+  specify "Resource xz Mavericks or newer dependency" do
+    allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.9"))
+    resource = Resource.new
+    resource.url("http://example.com/foo.tar.xz")
+    expect(subject.add(resource)).to be nil
+  end
+end
diff --git a/Library/Homebrew/test/os/mac/dependency_collector_test.rb b/Library/Homebrew/test/os/mac/dependency_collector_test.rb
deleted file mode 100644
index 4fdf3ebe4..000000000
--- a/Library/Homebrew/test/os/mac/dependency_collector_test.rb
+++ /dev/null
@@ -1,57 +0,0 @@
-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
-
-  def teardown
-    DependencyCollector.clear_cache
-  end
-
-  def test_tar_needs_xz_dependency
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.9"))
-    refute DependencyCollector.tar_needs_xz_dependency?
-  end
-
-  def test_ld64_dep_pre_leopard
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.4"))
-    assert_equal LD64Dependency.new, @d.build(:ld64)
-  end
-
-  def test_ld64_dep_leopard_or_newer
-    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
-
-  def test_resource_dep_xz_pre_mavericks
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.8"))
-    resource = Resource.new
-    resource.url("http://example.com/foo.tar.xz")
-    assert_equal Dependency.new("xz", [:build]), @d.add(resource)
-  end
-
-  def test_resource_dep_xz_mavericks_or_newer
-    MacOS.stubs(:version).returns(MacOS::Version.new("10.9"))
-    resource = Resource.new
-    resource.url("http://example.com/foo.tar.xz")
-    assert_nil @d.add(resource)
-  end
-end
diff --git a/Library/Homebrew/test/os/mac/diagnostic_spec.rb b/Library/Homebrew/test/os/mac/diagnostic_spec.rb
new file mode 100644
index 000000000..d2b38a332
--- /dev/null
+++ b/Library/Homebrew/test/os/mac/diagnostic_spec.rb
@@ -0,0 +1,42 @@
+require "diagnostic"
+
+describe Homebrew::Diagnostic::Checks do
+  specify "#check_for_other_package_managers" do
+    allow(MacOS).to receive(:macports_or_fink).and_return(["fink"])
+    expect(subject.check_for_other_package_managers)
+      .to match("You have MacPorts or Fink installed:")
+  end
+
+  specify "#check_for_unsupported_macos" do
+    ENV.delete("HOMEBREW_DEVELOPER")
+    allow(OS::Mac).to receive(:prerelease?).and_return(true)
+
+    expect(subject.check_for_unsupported_macos)
+      .to match("We do not provide support for this pre-release version.")
+  end
+
+  specify "#check_for_unsupported_curl_vars" do
+    allow(MacOS).to receive(:version).and_return(OS::Mac::Version.new("10.10"))
+    ENV["SSL_CERT_DIR"] = "/some/path"
+
+    expect(subject.check_for_unsupported_curl_vars)
+      .to match("SSL_CERT_DIR support was removed from Apple's curl.")
+  end
+
+  specify "#check_for_beta_xquartz" do
+    allow(MacOS::XQuartz).to receive(:version).and_return("2.7.10_beta2")
+
+    expect(subject.check_for_beta_xquartz)
+      .to match("The following beta release of XQuartz is installed: 2.7.10_beta2")
+  end
+
+  specify "#check_xcode_8_without_clt_on_el_capitan" do
+    allow(MacOS).to receive(:version).and_return(OS::Mac::Version.new("10.11"))
+    allow(MacOS::Xcode).to receive(:installed?).and_return(true)
+    allow(MacOS::Xcode).to receive(:version).and_return("8.0")
+    allow(MacOS::Xcode).to receive(:without_clt?).and_return(true)
+
+    expect(subject.check_xcode_8_without_clt_on_el_capitan)
+      .to match("You have Xcode 8 installed without the CLT")
+  end
+end
diff --git a/Library/Homebrew/test/os/mac/diagnostic_test.rb b/Library/Homebrew/test/os/mac/diagnostic_test.rb
deleted file mode 100644
index 655aa1d46..000000000
--- a/Library/Homebrew/test/os/mac/diagnostic_test.rb
+++ /dev/null
@@ -1,49 +0,0 @@
-require "testing_env"
-require "fileutils"
-require "pathname"
-require "diagnostic"
-
-class OSMacDiagnosticChecksTest < Homebrew::TestCase
-  def setup
-    @env = ENV.to_hash
-    @checks = Homebrew::Diagnostic::Checks.new
-  end
-
-  def teardown
-    ENV.replace(@env)
-  end
-
-  def test_check_for_other_package_managers
-    MacOS.stubs(:macports_or_fink).returns ["fink"]
-    assert_match "You have MacPorts or Fink installed:",
-      @checks.check_for_other_package_managers
-  end
-
-  def test_check_for_unsupported_macos
-    ARGV.stubs(:homebrew_developer?).returns false
-    OS::Mac.stubs(:prerelease?).returns true
-    assert_match "We do not provide support for this pre-release version.",
-      @checks.check_for_unsupported_macos
-  end
-
-  def test_check_for_unsupported_curl_vars
-    MacOS.stubs(:version).returns OS::Mac::Version.new("10.10")
-    ENV["SSL_CERT_DIR"] = "/some/path"
-
-    assert_match "SSL_CERT_DIR support was removed from Apple's curl.",
-      @checks.check_for_unsupported_curl_vars
-  end
-
-  def test_check_for_beta_xquartz
-    MacOS::XQuartz.stubs(:version).returns("2.7.10_beta2")
-    assert_match "The following beta release of XQuartz is installed: 2.7.10_beta2", @checks.check_for_beta_xquartz
-  end
-
-  def test_check_xcode_8_without_clt_on_el_capitan
-    MacOS.stubs(:version).returns OS::Mac::Version.new("10.11")
-    MacOS::Xcode.stubs(:installed?).returns true
-    MacOS::Xcode.stubs(:version).returns "8.0"
-    MacOS::Xcode.stubs(:without_clt?).returns true
-    assert_match "You have Xcode 8 installed without the CLT", @checks.check_xcode_8_without_clt_on_el_capitan
-  end
-end
diff --git a/Library/Homebrew/test/os/mac/java_requirement_spec.rb b/Library/Homebrew/test/os/mac/java_requirement_spec.rb
new file mode 100644
index 000000000..f6404db92
--- /dev/null
+++ b/Library/Homebrew/test/os/mac/java_requirement_spec.rb
@@ -0,0 +1,34 @@
+require "requirements/java_requirement"
+require "fileutils"
+
+describe JavaRequirement do
+  subject { described_class.new(%w[1.8]) }
+  let(:java_home) { Dir.mktmpdir }
+  let(:java_home_path) { Pathname.new(java_home) }
+
+  before(:each) do
+    FileUtils.mkdir java_home_path/"bin"
+    FileUtils.touch java_home_path/"bin/java"
+    allow(subject).to receive(:preferred_java).and_return(java_home_path/"bin/java")
+    expect(subject).to be_satisfied
+  end
+
+  after(:each) { java_home_path.rmtree }
+
+  specify "Apple Java environment" do
+    expect(ENV).to receive(:prepend_path)
+    expect(ENV).to receive(:append_to_cflags)
+
+    subject.modify_build_environment
+    expect(ENV["JAVA_HOME"]).to eq(java_home)
+  end
+
+  specify "Oracle Java environment" do
+    FileUtils.mkdir java_home_path/"include"
+    expect(ENV).to receive(:prepend_path)
+    expect(ENV).to receive(:append_to_cflags).twice
+
+    subject.modify_build_environment
+    expect(ENV["JAVA_HOME"]).to eq(java_home)
+  end
+end
diff --git a/Library/Homebrew/test/os/mac/keg_spec.rb b/Library/Homebrew/test/os/mac/keg_spec.rb
new file mode 100644
index 000000000..562c2ba6a
--- /dev/null
+++ b/Library/Homebrew/test/os/mac/keg_spec.rb
@@ -0,0 +1,32 @@
+require "keg"
+
+describe Keg do
+  include FileUtils
+
+  subject { described_class.new(keg_path) }
+
+  describe "#mach_o_files" do
+    let(:keg_path) { HOMEBREW_CELLAR/"a/1.0" }
+
+    before(:each) { (keg_path/"lib").mkpath }
+
+    after(:each) { subject.unlink }
+
+    it "skips hardlinks" do
+      cp dylib_path("i386"), keg_path/"lib/i386.dylib"
+      ln keg_path/"lib/i386.dylib", keg_path/"lib/i386_hardlink.dylib"
+
+      subject.link
+      expect(subject.mach_o_files.count).to eq(1)
+    end
+
+    it "isn't confused by symlinks" do
+      cp dylib_path("i386"), keg_path/"lib/i386.dylib"
+      ln keg_path/"lib/i386.dylib", keg_path/"lib/i386_hardlink.dylib"
+      ln_s keg_path/"lib/i386.dylib", keg_path/"lib/i386_symlink.dylib"
+
+      subject.link
+      expect(subject.mach_o_files.count).to eq(1)
+    end
+  end
+end
diff --git a/Library/Homebrew/test/os/mac/keg_test.rb b/Library/Homebrew/test/os/mac/keg_test.rb
deleted file mode 100644
index e79cbc921..000000000
--- a/Library/Homebrew/test/os/mac/keg_test.rb
+++ /dev/null
@@ -1,69 +0,0 @@
-require "testing_env"
-require "keg"
-require "stringio"
-
-class OSMacLinkTests < Homebrew::TestCase
-  include FileUtils
-
-  def setup
-    keg = HOMEBREW_CELLAR.join("foo", "1.0")
-    keg.join("bin").mkpath
-
-    %w[hiworld helloworld goodbye_cruel_world].each do |file|
-      touch keg.join("bin", file)
-    end
-
-    @keg = Keg.new(keg)
-    @dst = HOMEBREW_PREFIX.join("bin", "helloworld")
-    @nonexistent = Pathname.new("/some/nonexistent/path")
-
-    @mode = OpenStruct.new
-
-    @old_stdout = $stdout
-    $stdout = StringIO.new
-
-    mkpath HOMEBREW_PREFIX/"bin"
-    mkpath HOMEBREW_PREFIX/"lib"
-  end
-
-  def teardown
-    @keg.unlink
-    @keg.uninstall
-
-    $stdout = @old_stdout
-
-    rmtree HOMEBREW_PREFIX/"bin"
-    rmtree HOMEBREW_PREFIX/"lib"
-  end
-
-  def test_mach_o_files_skips_hardlinks
-    a = HOMEBREW_CELLAR/"a/1.0"
-    (a/"lib").mkpath
-    FileUtils.cp dylib_path("i386"), a/"lib/i386.dylib"
-    FileUtils.ln a/"lib/i386.dylib", a/"lib/i386_link.dylib"
-
-    keg = Keg.new(a)
-    keg.link
-
-    assert_equal 1, keg.mach_o_files.size
-  ensure
-    keg.unlink
-    keg.uninstall
-  end
-
-  def test_mach_o_files_isnt_confused_by_symlinks
-    a = HOMEBREW_CELLAR/"a/1.0"
-    (a/"lib").mkpath
-    FileUtils.cp dylib_path("i386"), a/"lib/i386.dylib"
-    FileUtils.ln a/"lib/i386.dylib", a/"lib/i386_link.dylib"
-    FileUtils.ln_s a/"lib/i386.dylib", a/"lib/1.dylib"
-
-    keg = Keg.new(a)
-    keg.link
-
-    assert_equal 1, keg.mach_o_files.size
-  ensure
-    keg.unlink
-    keg.uninstall
-  end
-end
diff --git a/Library/Homebrew/test/os/mac/language_test.rb b/Library/Homebrew/test/os/mac/language_test.rb
deleted file mode 100644
index e328db5e0..000000000
--- a/Library/Homebrew/test/os/mac/language_test.rb
+++ /dev/null
@@ -1,19 +0,0 @@
-require "testing_env"
-require "locale"
-require "os/mac"
-
-class OSMacLanguageTests < Homebrew::TestCase
-  def test_languages_format
-    OS::Mac.languages.each do |language|
-      assert_nothing_raised do
-        Locale.parse(language)
-      end
-    end
-  end
-
-  def test_language_format
-    assert_nothing_raised do
-      Locale.parse(OS::Mac.language)
-    end
-  end
-end
diff --git a/Library/Homebrew/test/os/mac/mach_spec.rb b/Library/Homebrew/test/os/mac/mach_spec.rb
new file mode 100644
index 000000000..5c9aafcbb
--- /dev/null
+++ b/Library/Homebrew/test/os/mac/mach_spec.rb
@@ -0,0 +1,198 @@
+describe "Mach-O Pathname tests" do
+  specify "fat dylib" do
+    pn = dylib_path("fat")
+    expect(pn).to be_universal
+    expect(pn).not_to be_i386
+    expect(pn).not_to be_x86_64
+    expect(pn).not_to be_ppc7400
+    expect(pn).not_to be_ppc64
+    expect(pn).to be_dylib
+    expect(pn).not_to be_mach_o_executable
+    expect(pn).not_to be_text_executable
+    expect(pn.arch).to eq(:universal)
+  end
+
+  specify "i386 dylib" do
+    pn = dylib_path("i386")
+    expect(pn).not_to be_universal
+    expect(pn).to be_i386
+    expect(pn).not_to be_x86_64
+    expect(pn).not_to be_ppc7400
+    expect(pn).not_to be_ppc64
+    expect(pn).to be_dylib
+    expect(pn).not_to be_mach_o_executable
+    expect(pn).not_to be_text_executable
+    expect(pn).not_to be_mach_o_bundle
+  end
+
+  specify "x86_64 dylib" do
+    pn = dylib_path("x86_64")
+    expect(pn).not_to be_universal
+    expect(pn).not_to be_i386
+    expect(pn).to be_x86_64
+    expect(pn).not_to be_ppc7400
+    expect(pn).not_to be_ppc64
+    expect(pn).to be_dylib
+    expect(pn).not_to be_mach_o_executable
+    expect(pn).not_to be_text_executable
+    expect(pn).not_to be_mach_o_bundle
+  end
+
+  specify "Mach-O executable" do
+    pn = Pathname.new("#{TEST_FIXTURE_DIR}/mach/a.out")
+    expect(pn).to be_universal
+    expect(pn).not_to be_i386
+    expect(pn).not_to be_x86_64
+    expect(pn).not_to be_ppc7400
+    expect(pn).not_to be_ppc64
+    expect(pn).not_to be_dylib
+    expect(pn).to be_mach_o_executable
+    expect(pn).not_to be_text_executable
+    expect(pn).not_to be_mach_o_bundle
+  end
+
+  specify "fat bundle" do
+    pn = bundle_path("fat")
+    expect(pn).to be_universal
+    expect(pn).not_to be_i386
+    expect(pn).not_to be_x86_64
+    expect(pn).not_to be_ppc7400
+    expect(pn).not_to be_ppc64
+    expect(pn).not_to be_dylib
+    expect(pn).not_to be_mach_o_executable
+    expect(pn).not_to be_text_executable
+    expect(pn).to be_mach_o_bundle
+  end
+
+  specify "i386 bundle" do
+    pn = bundle_path("i386")
+    expect(pn).not_to be_universal
+    expect(pn).to be_i386
+    expect(pn).not_to be_x86_64
+    expect(pn).not_to be_ppc7400
+    expect(pn).not_to be_ppc64
+    expect(pn).not_to be_dylib
+    expect(pn).not_to be_mach_o_executable
+    expect(pn).not_to be_text_executable
+    expect(pn).to be_mach_o_bundle
+  end
+
+  specify "x86_64 bundle" do
+    pn = bundle_path("x86_64")
+    expect(pn).not_to be_universal
+    expect(pn).not_to be_i386
+    expect(pn).to be_x86_64
+    expect(pn).not_to be_ppc7400
+    expect(pn).not_to be_ppc64
+    expect(pn).not_to be_dylib
+    expect(pn).not_to be_mach_o_executable
+    expect(pn).not_to be_text_executable
+    expect(pn).to be_mach_o_bundle
+  end
+
+  specify "non-Mach-O" do
+    pn = Pathname.new("#{TEST_FIXTURE_DIR}/tarballs/testball-0.1.tbz")
+    expect(pn).not_to be_universal
+    expect(pn).not_to be_i386
+    expect(pn).not_to be_x86_64
+    expect(pn).not_to be_ppc7400
+    expect(pn).not_to be_ppc64
+    expect(pn).not_to be_dylib
+    expect(pn).not_to be_mach_o_executable
+    expect(pn).not_to be_text_executable
+    expect(pn).not_to be_mach_o_bundle
+    expect(pn.arch).to eq(:dunno)
+  end
+end
+
+describe ArchitectureListExtension do
+  let(:archs) { [:i386, :x86_64, :ppc7400, :ppc64].extend(described_class) }
+
+  specify "universal checks" do
+    expect(archs).to be_universal
+    expect(archs).to be_intel_universal
+    expect(archs).to be_ppc_universal
+    expect(archs).to be_cross_universal
+    expect(archs).to be_fat
+
+    non_universal = [:i386].extend(described_class)
+    expect(non_universal).not_to be_universal
+
+    intel_only = [:i386, :x86_64].extend(described_class)
+    expect(intel_only).to be_universal
+    expect(intel_only).not_to be_ppc_universal
+    expect(intel_only).not_to be_cross_universal
+
+    ppc_only = [:ppc970, :ppc64].extend(described_class)
+    expect(ppc_only).to be_universal
+    expect(ppc_only).not_to be_intel_universal
+    expect(ppc_only).not_to be_cross_universal
+
+    cross = [:ppc7400, :i386].extend(described_class)
+    expect(cross).to be_universal
+    expect(cross).not_to be_intel_universal
+    expect(cross).not_to be_ppc_universal
+  end
+
+  specify "messaging flags" do
+    archs.remove_ppc!
+    expect(archs.length).to eq(2)
+    expect(archs.as_arch_flags).to match(/-arch i386/)
+    expect(archs.as_arch_flags).to match(/-arch x86_64/)
+  end
+
+  specify "architecture flags" do
+    pn = dylib_path("fat")
+    expect(pn.archs).to be_intel_universal
+    expect(pn.archs.as_arch_flags).to eq("-arch x86_64 -arch i386")
+    expect(pn.archs.as_cmake_arch_flags).to eq("x86_64;i386")
+  end
+end
+
+describe "text executables" do
+  let(:pn) { HOMEBREW_PREFIX/"an_executable" }
+
+  after(:each) { pn.unlink }
+
+  specify "simple shebang" do
+    pn.write "#!/bin/sh"
+    expect(pn).not_to be_universal
+    expect(pn).not_to be_i386
+    expect(pn).not_to be_x86_64
+    expect(pn).not_to be_ppc7400
+    expect(pn).not_to be_ppc64
+    expect(pn).not_to be_dylib
+    expect(pn).not_to be_mach_o_executable
+    expect(pn).to be_text_executable
+    expect(pn.archs).to eq([])
+    expect(pn.arch).to eq(:dunno)
+  end
+
+  specify "shebang with options" do
+    pn.write "#! /usr/bin/perl -w"
+    expect(pn).not_to be_universal
+    expect(pn).not_to be_i386
+    expect(pn).not_to be_x86_64
+    expect(pn).not_to be_ppc7400
+    expect(pn).not_to be_ppc64
+    expect(pn).not_to be_dylib
+    expect(pn).not_to be_mach_o_executable
+    expect(pn).to be_text_executable
+    expect(pn.archs).to eq([])
+    expect(pn.arch).to eq(:dunno)
+  end
+
+  specify "malformed shebang" do
+    pn.write " #!"
+    expect(pn).not_to be_universal
+    expect(pn).not_to be_i386
+    expect(pn).not_to be_x86_64
+    expect(pn).not_to be_ppc7400
+    expect(pn).not_to be_ppc64
+    expect(pn).not_to be_dylib
+    expect(pn).not_to be_mach_o_executable
+    expect(pn).not_to be_text_executable
+    expect(pn.archs).to eq([])
+    expect(pn.arch).to eq(:dunno)
+  end
+end
diff --git a/Library/Homebrew/test/os/mac/mach_test.rb b/Library/Homebrew/test/os/mac/mach_test.rb
deleted file mode 100644
index a42f7316b..000000000
--- a/Library/Homebrew/test/os/mac/mach_test.rb
+++ /dev/null
@@ -1,208 +0,0 @@
-require "testing_env"
-
-class MachOPathnameTests < Homebrew::TestCase
-  def test_fat_dylib
-    pn = dylib_path("fat")
-    assert_predicate pn, :universal?
-    refute_predicate pn, :i386?
-    refute_predicate pn, :x86_64?
-    refute_predicate pn, :ppc7400?
-    refute_predicate pn, :ppc64?
-    assert_predicate pn, :dylib?
-    refute_predicate pn, :mach_o_executable?
-    refute_predicate pn, :text_executable?
-    assert_equal :universal, pn.arch
-  end
-
-  def test_i386_dylib
-    pn = dylib_path("i386")
-    refute_predicate pn, :universal?
-    assert_predicate pn, :i386?
-    refute_predicate pn, :x86_64?
-    refute_predicate pn, :ppc7400?
-    refute_predicate pn, :ppc64?
-    assert_predicate pn, :dylib?
-    refute_predicate pn, :mach_o_executable?
-    refute_predicate pn, :text_executable?
-    refute_predicate pn, :mach_o_bundle?
-  end
-
-  def test_x86_64_dylib
-    pn = dylib_path("x86_64")
-    refute_predicate pn, :universal?
-    refute_predicate pn, :i386?
-    assert_predicate pn, :x86_64?
-    refute_predicate pn, :ppc7400?
-    refute_predicate pn, :ppc64?
-    assert_predicate pn, :dylib?
-    refute_predicate pn, :mach_o_executable?
-    refute_predicate pn, :text_executable?
-    refute_predicate pn, :mach_o_bundle?
-  end
-
-  def test_mach_o_executable
-    pn = Pathname.new("#{TEST_FIXTURE_DIR}/mach/a.out")
-    assert_predicate pn, :universal?
-    refute_predicate pn, :i386?
-    refute_predicate pn, :x86_64?
-    refute_predicate pn, :ppc7400?
-    refute_predicate pn, :ppc64?
-    refute_predicate pn, :dylib?
-    assert_predicate pn, :mach_o_executable?
-    refute_predicate pn, :text_executable?
-    refute_predicate pn, :mach_o_bundle?
-  end
-
-  def test_fat_bundle
-    pn = bundle_path("fat")
-    assert_predicate pn, :universal?
-    refute_predicate pn, :i386?
-    refute_predicate pn, :x86_64?
-    refute_predicate pn, :ppc7400?
-    refute_predicate pn, :ppc64?
-    refute_predicate pn, :dylib?
-    refute_predicate pn, :mach_o_executable?
-    refute_predicate pn, :text_executable?
-    assert_predicate pn, :mach_o_bundle?
-  end
-
-  def test_i386_bundle
-    pn = bundle_path("i386")
-    refute_predicate pn, :universal?
-    assert_predicate pn, :i386?
-    refute_predicate pn, :x86_64?
-    refute_predicate pn, :ppc7400?
-    refute_predicate pn, :ppc64?
-    refute_predicate pn, :dylib?
-    refute_predicate pn, :mach_o_executable?
-    refute_predicate pn, :text_executable?
-    assert_predicate pn, :mach_o_bundle?
-  end
-
-  def test_x86_64_bundle
-    pn = bundle_path("x86_64")
-    refute_predicate pn, :universal?
-    refute_predicate pn, :i386?
-    assert_predicate pn, :x86_64?
-    refute_predicate pn, :ppc7400?
-    refute_predicate pn, :ppc64?
-    refute_predicate pn, :dylib?
-    refute_predicate pn, :mach_o_executable?
-    refute_predicate pn, :text_executable?
-    assert_predicate pn, :mach_o_bundle?
-  end
-
-  def test_non_mach_o
-    pn = Pathname.new("#{TEST_FIXTURE_DIR}/tarballs/testball-0.1.tbz")
-    refute_predicate pn, :universal?
-    refute_predicate pn, :i386?
-    refute_predicate pn, :x86_64?
-    refute_predicate pn, :ppc7400?
-    refute_predicate pn, :ppc64?
-    refute_predicate pn, :dylib?
-    refute_predicate pn, :mach_o_executable?
-    refute_predicate pn, :text_executable?
-    refute_predicate pn, :mach_o_bundle?
-    assert_equal :dunno, pn.arch
-  end
-end
-
-class ArchitectureListExtensionTests < MachOPathnameTests
-  def setup
-    @archs = [:i386, :x86_64, :ppc7400, :ppc64].extend(ArchitectureListExtension)
-  end
-
-  def test_architecture_list_extension_universal_checks
-    assert_predicate @archs, :universal?
-    assert_predicate @archs, :intel_universal?
-    assert_predicate @archs, :ppc_universal?
-    assert_predicate @archs, :cross_universal?
-    assert_predicate @archs, :fat?
-
-    non_universal = [:i386].extend ArchitectureListExtension
-    refute_predicate non_universal, :universal?
-
-    intel_only = [:i386, :x86_64].extend ArchitectureListExtension
-    assert_predicate intel_only, :universal?
-    refute_predicate intel_only, :ppc_universal?
-    refute_predicate intel_only, :cross_universal?
-
-    ppc_only = [:ppc970, :ppc64].extend ArchitectureListExtension
-    assert_predicate ppc_only, :universal?
-    refute_predicate ppc_only, :intel_universal?
-    refute_predicate ppc_only, :cross_universal?
-
-    cross = [:ppc7400, :i386].extend ArchitectureListExtension
-    assert_predicate cross, :universal?
-    refute_predicate cross, :intel_universal?
-    refute_predicate cross, :ppc_universal?
-  end
-
-  def test_architecture_list_extension_massaging_flags
-    @archs.remove_ppc!
-    assert_equal 2, @archs.length
-    assert_match(/-arch i386/, @archs.as_arch_flags)
-    assert_match(/-arch x86_64/, @archs.as_arch_flags)
-  end
-
-  def test_architecture_list_arch_flags_methods
-    pn = dylib_path("fat")
-    assert_predicate pn.archs, :intel_universal?
-    assert_equal "-arch x86_64 -arch i386", pn.archs.as_arch_flags
-    assert_equal "x86_64;i386", pn.archs.as_cmake_arch_flags
-  end
-end
-
-class TextExecutableTests < Homebrew::TestCase
-  attr_reader :pn
-
-  def setup
-    @pn = HOMEBREW_PREFIX.join("an_executable")
-  end
-
-  def teardown
-    HOMEBREW_PREFIX.join("an_executable").unlink
-  end
-
-  def test_simple_shebang
-    pn.write "#!/bin/sh"
-    refute_predicate pn, :universal?
-    refute_predicate pn, :i386?
-    refute_predicate pn, :x86_64?
-    refute_predicate pn, :ppc7400?
-    refute_predicate pn, :ppc64?
-    refute_predicate pn, :dylib?
-    refute_predicate pn, :mach_o_executable?
-    assert_predicate pn, :text_executable?
-    assert_equal [], pn.archs
-    assert_equal :dunno, pn.arch
-  end
-
-  def test_shebang_with_options
-    pn.write "#! /usr/bin/perl -w"
-    refute_predicate pn, :universal?
-    refute_predicate pn, :i386?
-    refute_predicate pn, :x86_64?
-    refute_predicate pn, :ppc7400?
-    refute_predicate pn, :ppc64?
-    refute_predicate pn, :dylib?
-    refute_predicate pn, :mach_o_executable?
-    assert_predicate pn, :text_executable?
-    assert_equal [], pn.archs
-    assert_equal :dunno, pn.arch
-  end
-
-  def test_malformed_shebang
-    pn.write " #!"
-    refute_predicate pn, :universal?
-    refute_predicate pn, :i386?
-    refute_predicate pn, :x86_64?
-    refute_predicate pn, :ppc7400?
-    refute_predicate pn, :ppc64?
-    refute_predicate pn, :dylib?
-    refute_predicate pn, :mach_o_executable?
-    refute_predicate pn, :text_executable?
-    assert_equal [], pn.archs
-    assert_equal :dunno, pn.arch
-  end
-end
diff --git a/Library/Homebrew/test/os/mac/version_spec.rb b/Library/Homebrew/test/os/mac/version_spec.rb
new file mode 100644
index 000000000..797207b67
--- /dev/null
+++ b/Library/Homebrew/test/os/mac/version_spec.rb
@@ -0,0 +1,51 @@
+require "version"
+require "os/mac/version"
+
+describe OS::Mac::Version do
+  subject { described_class.new("10.7") }
+
+  specify "comparison with Symbol" do
+    expect(subject).to be > :snow_leopard
+    expect(subject).to be == :lion
+    expect(subject).to be === :lion # rubocop:disable Style/CaseEquality
+    expect(subject).to be < :mountain_lion
+  end
+
+  specify "comparison with Fixnum" do
+    expect(subject).to be > 10
+    expect(subject).to be < 11
+  end
+
+  specify "comparison with Float" do
+    expect(subject).to be > 10.6
+    expect(subject).to be == 10.7
+    expect(subject).to be === 10.7 # rubocop:disable Style/CaseEquality
+    expect(subject).to be < 10.8
+  end
+
+  specify "comparison with String" do
+    expect(subject).to be > "10.6"
+    expect(subject).to be == "10.7"
+    expect(subject).to be === "10.7" # rubocop:disable Style/CaseEquality
+    expect(subject).to be < "10.8"
+  end
+
+  specify "comparison with Version" do
+    expect(subject).to be > Version.create("10.6")
+    expect(subject).to be == Version.create("10.7")
+    expect(subject).to be === Version.create("10.7") # rubocop:disable Style/CaseEquality
+    expect(subject).to be < Version.create("10.8")
+  end
+
+  specify "#from_symbol" do
+    expect(described_class.from_symbol(:lion)).to eq(subject)
+    expect { described_class.from_symbol(:foo) }
+      .to raise_error(ArgumentError)
+  end
+
+  specify "#pretty_name" do
+    expect(described_class.new("10.11").pretty_name).to eq("El Capitan")
+    expect(described_class.new("10.8").pretty_name).to eq("Mountain Lion")
+    expect(described_class.new("10.10").pretty_name).to eq("Yosemite")
+  end
+end
diff --git a/Library/Homebrew/test/os/mac/version_test.rb b/Library/Homebrew/test/os/mac/version_test.rb
deleted file mode 100644
index f702c7097..000000000
--- a/Library/Homebrew/test/os/mac/version_test.rb
+++ /dev/null
@@ -1,53 +0,0 @@
-require "testing_env"
-require "version"
-require "os/mac/version"
-
-class OSMacVersionTests < Homebrew::TestCase
-  def setup
-    @v = MacOS::Version.new("10.7")
-  end
-
-  def test_compare_with_symbol
-    assert_operator @v, :>, :snow_leopard
-    assert_operator @v, :==, :lion
-    assert_operator @v, :===, :lion
-    assert_operator @v, :<, :mountain_lion
-  end
-
-  def test_compare_with_fixnum
-    assert_operator @v, :>, 10
-    assert_operator @v, :<, 11
-  end
-
-  def test_compare_with_float
-    assert_operator @v, :>, 10.6
-    assert_operator @v, :==, 10.7
-    assert_operator @v, :===, 10.7
-    assert_operator @v, :<, 10.8
-  end
-
-  def test_compare_with_string
-    assert_operator @v, :>, "10.6"
-    assert_operator @v, :==, "10.7"
-    assert_operator @v, :===, "10.7"
-    assert_operator @v, :<, "10.8"
-  end
-
-  def test_compare_with_version
-    assert_operator @v, :>, Version.create("10.6")
-    assert_operator @v, :==, Version.create("10.7")
-    assert_operator @v, :===, Version.create("10.7")
-    assert_operator @v, :<, Version.create("10.8")
-  end
-
-  def test_from_symbol
-    assert_equal @v, MacOS::Version.from_symbol(:lion)
-    assert_raises(ArgumentError) { MacOS::Version.from_symbol(:foo) }
-  end
-
-  def test_pretty_name
-    assert_equal "El Capitan", MacOS::Version.new("10.11").pretty_name
-    assert_equal "Mountain Lion", MacOS::Version.new("10.8").pretty_name
-    assert_equal "Yosemite", MacOS::Version.new("10.10").pretty_name
-  end
-end
diff --git a/Library/Homebrew/test/os/mac_spec.rb b/Library/Homebrew/test/os/mac_spec.rb
new file mode 100644
index 000000000..641782451
--- /dev/null
+++ b/Library/Homebrew/test/os/mac_spec.rb
@@ -0,0 +1,22 @@
+require "locale"
+require "os/mac"
+
+describe OS::Mac do
+  describe "::languages" do
+    specify "all languages can be parsed by Locale::parse" do
+      subject.languages.each do |language|
+        expect { Locale.parse(language) }.not_to raise_error
+      end
+    end
+  end
+
+  describe "::language" do
+    it "returns the first item from #languages" do
+      expect(subject.language).to eq(subject.languages.first)
+    end
+
+    it "can be parsed by Locale::parse" do
+      expect { Locale.parse(subject.language) }.not_to raise_error
+    end
+  end
+end
diff --git a/Library/Homebrew/test/outdated_test.rb b/Library/Homebrew/test/outdated_test.rb
deleted file mode 100644
index 3e7148ded..000000000
--- a/Library/Homebrew/test/outdated_test.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestOutdated < IntegrationCommandTestCase
-  def test_outdated
-    setup_test_formula "testball"
-    (HOMEBREW_CELLAR/"testball/0.0.1/foo").mkpath
-
-    assert_equal "testball", cmd("outdated")
-  end
-end
diff --git a/Library/Homebrew/test/patch_spec.rb b/Library/Homebrew/test/patch_spec.rb
new file mode 100644
index 000000000..22c103662
--- /dev/null
+++ b/Library/Homebrew/test/patch_spec.rb
@@ -0,0 +1,165 @@
+require "patch"
+
+describe Patch do
+  describe "#create" do
+    context "simple patch" do
+      subject { described_class.create(:p2, nil) }
+      it { is_expected.to be_kind_of ExternalPatch }
+      it { is_expected.to be_external }
+      its(:strip) { is_expected.to eq(:p2) }
+    end
+
+    context "string patch" do
+      subject { described_class.create(:p0, "foo") }
+      it { is_expected.to be_kind_of StringPatch }
+      its(:strip) { is_expected.to eq(:p0) }
+    end
+
+    context "string patch without strip" do
+      subject { described_class.create("foo", nil) }
+      it { is_expected.to be_kind_of StringPatch }
+      its(:strip) { is_expected.to eq(:p1) }
+    end
+
+    context "data patch" do
+      subject { described_class.create(:p0, :DATA) }
+      it { is_expected.to be_kind_of DATAPatch }
+      its(:strip) { is_expected.to eq(:p0) }
+    end
+
+    context "data patch without strip" do
+      subject { described_class.create(:DATA, nil) }
+      it { is_expected.to be_kind_of DATAPatch }
+      its(:strip) { is_expected.to eq(:p1) }
+    end
+
+    it "raises an error for unknown values" do
+      expect {
+        described_class.create(Object.new)
+      }.to raise_error(ArgumentError)
+
+      expect {
+        described_class.create(Object.new, Object.new)
+      }.to raise_error(ArgumentError)
+    end
+  end
+
+  describe "#patch_files" do
+    subject { described_class.create(:p2, nil) }
+
+    context "empty patch" do
+      its(:resource) { is_expected.to be_kind_of Resource::Patch }
+      its(:patch_files) { is_expected.to eq(subject.resource.patch_files) }
+      its(:patch_files) { is_expected.to eq([]) }
+    end
+
+    it "returns applied patch files" do
+      subject.resource.apply("patch1.diff")
+      expect(subject.patch_files).to eq(["patch1.diff"])
+
+      subject.resource.apply("patch2.diff", "patch3.diff")
+      expect(subject.patch_files).to eq(["patch1.diff", "patch2.diff", "patch3.diff"])
+
+      subject.resource.apply(["patch4.diff", "patch5.diff"])
+      expect(subject.patch_files.count).to eq(5)
+
+      subject.resource.apply("patch4.diff", ["patch5.diff", "patch6.diff"], "patch7.diff")
+      expect(subject.patch_files.count).to eq(7)
+    end
+  end
+
+  describe "#normalize_legacy_patches" do
+    it "can create a patch from a single string" do
+      patches = described_class.normalize_legacy_patches("http://example.com/patch.diff")
+      expect(patches.length).to eq(1)
+      expect(patches.first.strip).to eq(:p1)
+    end
+
+    it "can create patches from an array" do
+      patches = described_class.normalize_legacy_patches(
+        %w[http://example.com/patch1.diff http://example.com/patch2.diff],
+      )
+
+      expect(patches.length).to eq(2)
+      expect(patches[0].strip).to eq(:p1)
+      expect(patches[1].strip).to eq(:p1)
+    end
+
+    it "can create patches from a :p0 hash" do
+      patches = Patch.normalize_legacy_patches(
+        p0: "http://example.com/patch.diff",
+      )
+
+      expect(patches.length).to eq(1)
+      expect(patches.first.strip).to eq(:p0)
+    end
+
+    it "can create patches from a :p1 hash" do
+      patches = Patch.normalize_legacy_patches(
+        p1: "http://example.com/patch.diff",
+      )
+
+      expect(patches.length).to eq(1)
+      expect(patches.first.strip).to eq(:p1)
+    end
+
+    it "can create patches from a mixed hash" do
+      patches = Patch.normalize_legacy_patches(
+        p1: "http://example.com/patch1.diff",
+        p0: "http://example.com/patch0.diff",
+      )
+
+      expect(patches.length).to eq(2)
+      expect(patches.count { |p| p.strip == :p0 }).to eq(1)
+      expect(patches.count { |p| p.strip == :p1 }).to eq(1)
+    end
+
+    it "can create patches from a mixed hash with array" do
+      patches = Patch.normalize_legacy_patches(
+        p1: [
+          "http://example.com/patch10.diff",
+          "http://example.com/patch11.diff",
+        ],
+        p0: [
+          "http://example.com/patch00.diff",
+          "http://example.com/patch01.diff",
+        ],
+      )
+
+      expect(patches.length).to eq(4)
+      expect(patches.count { |p| p.strip == :p0 }).to eq(2)
+      expect(patches.count { |p| p.strip == :p1 }).to eq(2)
+    end
+
+    it "returns an empty array if given nil" do
+      expect(Patch.normalize_legacy_patches(nil)).to be_empty
+    end
+  end
+end
+
+describe EmbeddedPatch do
+  describe "#new" do
+    subject { described_class.new(:p1) }
+    its(:inspect) { is_expected.to eq("#<EmbeddedPatch: :p1>") }
+  end
+end
+
+describe ExternalPatch do
+  subject { described_class.new(:p1) { url "file:///my.patch" } }
+
+  describe "#url" do
+    its(:url) { is_expected.to eq("file:///my.patch") }
+  end
+
+  describe "#inspect" do
+    its(:inspect) { is_expected.to eq('#<ExternalPatch: :p1 "file:///my.patch">') }
+  end
+
+  describe "#cached_download" do
+    before(:each) do
+      allow(subject.resource).to receive(:cached_download).and_return("/tmp/foo.tar.gz")
+    end
+
+    its(:cached_download) { is_expected.to eq("/tmp/foo.tar.gz") }
+  end
+end
diff --git a/Library/Homebrew/test/patch_test.rb b/Library/Homebrew/test/patch_test.rb
deleted file mode 100644
index 62624720e..000000000
--- a/Library/Homebrew/test/patch_test.rb
+++ /dev/null
@@ -1,154 +0,0 @@
-require "testing_env"
-require "patch"
-
-class PatchTests < Homebrew::TestCase
-  def test_create_simple
-    patch = Patch.create(:p2, nil)
-    assert_kind_of ExternalPatch, patch
-    assert_predicate patch, :external?
-    assert_equal :p2, patch.strip
-  end
-
-  def test_create_string
-    patch = Patch.create(:p0, "foo")
-    assert_kind_of StringPatch, patch
-    assert_equal :p0, patch.strip
-  end
-
-  def test_create_string_without_strip
-    patch = Patch.create("foo", nil)
-    assert_kind_of StringPatch, patch
-    assert_equal :p1, patch.strip
-  end
-
-  def test_create_data
-    patch = Patch.create(:p0, :DATA)
-    assert_kind_of DATAPatch, patch
-    assert_equal :p0, patch.strip
-  end
-
-  def test_create_data_without_strip
-    patch = Patch.create(:DATA, nil)
-    assert_kind_of DATAPatch, patch
-    assert_equal :p1, patch.strip
-  end
-
-  def test_raises_for_unknown_values
-    assert_raises(ArgumentError) { Patch.create(Object.new) }
-    assert_raises(ArgumentError) { Patch.create(Object.new, Object.new) }
-  end
-end
-
-class LegacyPatchTests < Homebrew::TestCase
-  def test_patch_single_string
-    patches = Patch.normalize_legacy_patches("http://example.com/patch.diff")
-    assert_equal 1, patches.length
-    assert_equal :p1, patches.first.strip
-  end
-
-  def test_patch_array
-    patches = Patch.normalize_legacy_patches(
-      %w[http://example.com/patch1.diff http://example.com/patch2.diff]
-    )
-
-    assert_equal 2, patches.length
-    assert_equal :p1, patches[0].strip
-    assert_equal :p1, patches[1].strip
-  end
-
-  def test_p0_hash_to_string
-    patches = Patch.normalize_legacy_patches(
-      p0: "http://example.com/patch.diff"
-    )
-
-    assert_equal 1, patches.length
-    assert_equal :p0, patches.first.strip
-  end
-
-  def test_p1_hash_to_string
-    patches = Patch.normalize_legacy_patches(
-      p1: "http://example.com/patch.diff"
-    )
-
-    assert_equal 1, patches.length
-    assert_equal :p1, patches.first.strip
-  end
-
-  def test_mixed_hash_to_strings
-    patches = Patch.normalize_legacy_patches(
-      p1: "http://example.com/patch1.diff",
-      p0: "http://example.com/patch0.diff"
-    )
-    assert_equal 2, patches.length
-    assert_equal 1, patches.count { |p| p.strip == :p0 }
-    assert_equal 1, patches.count { |p| p.strip == :p1 }
-  end
-
-  def test_mixed_hash_to_arrays
-    patches = Patch.normalize_legacy_patches(
-      p1: ["http://example.com/patch10.diff",
-           "http://example.com/patch11.diff"],
-      p0: ["http://example.com/patch00.diff",
-           "http://example.com/patch01.diff"]
-    )
-
-    assert_equal 4, patches.length
-    assert_equal 2, patches.count { |p| p.strip == :p0 }
-    assert_equal 2, patches.count { |p| p.strip == :p1 }
-  end
-
-  def test_nil
-    assert_empty Patch.normalize_legacy_patches(nil)
-  end
-end
-
-class EmbeddedPatchTests < Homebrew::TestCase
-  def test_inspect
-    p = EmbeddedPatch.new :p1
-    assert_equal "#<EmbeddedPatch: :p1>", p.inspect
-  end
-end
-
-class ExternalPatchTests < Homebrew::TestCase
-  def setup
-    @p = ExternalPatch.new(:p1) { url "file:///my.patch" }
-  end
-
-  def test_url
-    assert_equal "file:///my.patch", @p.url
-  end
-
-  def test_inspect
-    assert_equal '#<ExternalPatch: :p1 "file:///my.patch">', @p.inspect
-  end
-
-  def test_cached_download
-    @p.resource.stubs(:cached_download).returns "/tmp/foo.tar.gz"
-    assert_equal "/tmp/foo.tar.gz", @p.cached_download
-  end
-end
-
-class ApplyPatchTests < Homebrew::TestCase
-  def test_empty_patch_files
-    patch = Patch.create(:p2, nil)
-    resource = patch.resource
-    patch_files = patch.patch_files
-    assert_kind_of Resource::Patch, resource
-    assert_equal patch_files, resource.patch_files
-    assert_equal patch_files, []
-  end
-
-  def test_resource_patch_apply_method
-    patch = Patch.create(:p2, nil)
-    resource = patch.resource
-    patch_files = patch.patch_files
-    resource.apply("patch1.diff")
-    assert_equal patch_files, ["patch1.diff"]
-    resource.apply("patch2.diff", "patch3.diff")
-    assert_equal patch_files, ["patch1.diff", "patch2.diff", "patch3.diff"]
-    resource.apply(["patch4.diff", "patch5.diff"])
-    assert_equal patch_files.count, 5
-    resource.apply("patch4.diff", ["patch5.diff", "patch6.diff"], "patch7.diff")
-    assert_equal patch_files.count, 7
-  end
-end
diff --git a/Library/Homebrew/test/patching_spec.rb b/Library/Homebrew/test/patching_spec.rb
new file mode 100644
index 000000000..dd849ca92
--- /dev/null
+++ b/Library/Homebrew/test/patching_spec.rb
@@ -0,0 +1,289 @@
+require "formula"
+
+describe "patching" do
+  TESTBALL_URL = "file://#{TEST_FIXTURE_DIR}/tarballs/testball-0.1.tbz".freeze
+  TESTBALL_PATCHES_URL = "file://#{TEST_FIXTURE_DIR}/tarballs/testball-0.1-patches.tgz".freeze
+  PATCH_URL_A = "file://#{TEST_FIXTURE_DIR}/patches/noop-a.diff".freeze
+  PATCH_URL_B = "file://#{TEST_FIXTURE_DIR}/patches/noop-b.diff".freeze
+  PATCH_A_CONTENTS = File.read "#{TEST_FIXTURE_DIR}/patches/noop-a.diff"
+  PATCH_B_CONTENTS = File.read "#{TEST_FIXTURE_DIR}/patches/noop-b.diff"
+  APPLY_A = "noop-a.diff".freeze
+  APPLY_B = "noop-b.diff".freeze
+  APPLY_C = "noop-c.diff".freeze
+
+  def formula(name = "formula_name", path: Formulary.core_path(name), spec: :stable, alias_path: nil, &block)
+    Class.new(Formula) {
+      url TESTBALL_URL
+      sha256 TESTBALL_SHA256
+      class_eval(&block)
+    }.new(name, path, spec, alias_path: alias_path)
+  end
+
+  matcher :be_patched do
+    match do |formula|
+      shutup do
+        formula.brew do
+          formula.patch
+          s = File.read("libexec/NOOP")
+          expect(s).not_to include("NOOP"), "libexec/NOOP was not patched as expected"
+          expect(s).to include("ABCD"), "libexec/NOOP was not patched as expected"
+        end
+      end
+    end
+  end
+
+  matcher :be_sequentially_patched do
+    match do |formula|
+      shutup do
+        formula.brew do
+          formula.patch
+          s = File.read("libexec/NOOP")
+          expect(s).not_to include("NOOP"), "libexec/NOOP was not patched as expected"
+          expect(s).not_to include("ABCD"), "libexec/NOOP was not patched as expected"
+          expect(s).to include("1234"), "libexec/NOOP was not patched as expected"
+        end
+      end
+    end
+  end
+
+  matcher :miss_apply do
+    match do |formula|
+      expect {
+        shutup do
+          formula.brew do
+            formula.patch
+          end
+        end
+      }.to raise_error(MissingApplyError)
+    end
+  end
+
+  specify "single_patch" do
+    expect(
+      formula do
+        def patches
+          PATCH_URL_A
+        end
+      end,
+    ).to be_patched
+  end
+
+  specify "single_patch_dsl" do
+    expect(
+      formula do
+        patch do
+          url PATCH_URL_A
+          sha256 PATCH_A_SHA256
+        end
+      end,
+    ).to be_patched
+  end
+
+  specify "single_patch_dsl_with_apply" do
+    expect(
+      formula do
+        patch do
+          url TESTBALL_PATCHES_URL
+          sha256 TESTBALL_PATCHES_SHA256
+          apply APPLY_A
+        end
+      end,
+    ).to be_patched
+  end
+
+  specify "single_patch_dsl_with_sequential_apply" do
+    expect(
+      formula do
+        patch do
+          url TESTBALL_PATCHES_URL
+          sha256 TESTBALL_PATCHES_SHA256
+          apply APPLY_A, APPLY_C
+        end
+      end,
+    ).to be_sequentially_patched
+  end
+
+  specify "single_patch_dsl_with_strip" do
+    expect(
+      formula do
+        patch :p1 do
+          url PATCH_URL_A
+          sha256 PATCH_A_SHA256
+        end
+      end,
+    ).to be_patched
+  end
+
+  specify "single_patch_dsl_with_strip_with_apply" do
+    expect(
+      formula do
+        patch :p1 do
+          url TESTBALL_PATCHES_URL
+          sha256 TESTBALL_PATCHES_SHA256
+          apply APPLY_A
+        end
+      end,
+    ).to be_patched
+  end
+
+  specify "single_patch_dsl_with_incorrect_strip" do
+    expect {
+      shutup do
+        f = formula do
+          patch :p0 do
+            url PATCH_URL_A
+            sha256 PATCH_A_SHA256
+          end
+        end
+
+        f.brew { |formula, _staging| formula.patch }
+      end
+    }.to raise_error(ErrorDuringExecution)
+  end
+
+  specify "single_patch_dsl_with_incorrect_strip_with_apply" do
+    expect {
+      shutup do
+        f = formula do
+          patch :p0 do
+            url TESTBALL_PATCHES_URL
+            sha256 TESTBALL_PATCHES_SHA256
+            apply APPLY_A
+          end
+        end
+
+        f.brew { |formula, _staging| formula.patch }
+      end
+    }.to raise_error(ErrorDuringExecution)
+  end
+
+  specify "patch_p0_dsl" do
+    expect(
+      formula do
+        patch :p0 do
+          url PATCH_URL_B
+          sha256 PATCH_B_SHA256
+        end
+      end,
+    ).to be_patched
+  end
+
+  specify "patch_p0_dsl_with_apply" do
+    expect(
+      formula do
+        patch :p0 do
+          url TESTBALL_PATCHES_URL
+          sha256 TESTBALL_PATCHES_SHA256
+          apply APPLY_B
+        end
+      end,
+    ).to be_patched
+  end
+
+  specify "patch_p0" do
+    expect(
+      formula do
+        def patches
+          { p0: PATCH_URL_B }
+        end
+      end,
+    ).to be_patched
+  end
+
+  specify "patch_array" do
+    expect(
+      formula do
+        def patches
+          [PATCH_URL_A]
+        end
+      end,
+    ).to be_patched
+  end
+
+  specify "patch_hash" do
+    expect(
+      formula do
+        def patches
+          { p1: PATCH_URL_A }
+        end
+      end,
+    ).to be_patched
+  end
+
+  specify "patch_hash_array" do
+    expect(
+      formula do
+        def patches
+          { p1: [PATCH_URL_A] }
+        end
+      end,
+    ).to be_patched
+  end
+
+  specify "patch_string" do
+    expect(formula { patch PATCH_A_CONTENTS }).to be_patched
+  end
+
+  specify "patch_string_with_strip" do
+    expect(formula { patch :p0, PATCH_B_CONTENTS }).to be_patched
+  end
+
+  specify "patch_data_constant" do
+    expect(
+      formula("test", path: Pathname.new(__FILE__).expand_path) do
+        def patches
+          :DATA
+        end
+      end,
+    ).to be_patched
+  end
+
+  specify "single_patch_missing_apply_fail" do
+    expect(
+      formula do
+        def patches
+          TESTBALL_PATCHES_URL
+        end
+      end,
+    ).to miss_apply
+  end
+
+  specify "single_patch_dsl_missing_apply_fail" do
+    expect(
+      formula do
+        patch do
+          url TESTBALL_PATCHES_URL
+          sha256 TESTBALL_PATCHES_SHA256
+        end
+      end,
+    ).to miss_apply
+  end
+
+  specify "single_patch_dsl_with_apply_enoent_fail" do
+    expect {
+      shutup do
+        f = formula do
+          patch do
+            url TESTBALL_PATCHES_URL
+            sha256 TESTBALL_PATCHES_SHA256
+            apply "patches/#{APPLY_A}"
+          end
+        end
+
+        f.brew { |formula, _staging| formula.patch }
+      end
+    }.to raise_error(ErrorDuringExecution)
+  end
+end
+
+__END__
+diff --git a/libexec/NOOP b/libexec/NOOP
+index bfdda4c..e08d8f4 100755
+--- a/libexec/NOOP
++++ b/libexec/NOOP
+@@ -1,2 +1,2 @@
+ #!/bin/bash
+-echo NOOP
+\ No newline at end of file
++echo ABCD
+\ No newline at end of file
diff --git a/Library/Homebrew/test/patching_test.rb b/Library/Homebrew/test/patching_test.rb
deleted file mode 100644
index ac14c8e1e..000000000
--- a/Library/Homebrew/test/patching_test.rb
+++ /dev/null
@@ -1,253 +0,0 @@
-require "testing_env"
-require "formula"
-
-class PatchingTests < Homebrew::TestCase
-  TESTBALL_URL = "file://#{TEST_FIXTURE_DIR}/tarballs/testball-0.1.tbz".freeze
-  TESTBALL_PATCHES_URL = "file://#{TEST_FIXTURE_DIR}/tarballs/testball-0.1-patches.tgz".freeze
-  PATCH_URL_A = "file://#{TEST_FIXTURE_DIR}/patches/noop-a.diff".freeze
-  PATCH_URL_B = "file://#{TEST_FIXTURE_DIR}/patches/noop-b.diff".freeze
-  PATCH_A_CONTENTS = File.read "#{TEST_FIXTURE_DIR}/patches/noop-a.diff"
-  PATCH_B_CONTENTS = File.read "#{TEST_FIXTURE_DIR}/patches/noop-b.diff"
-  APPLY_A = "noop-a.diff".freeze
-  APPLY_B = "noop-b.diff".freeze
-  APPLY_C = "noop-c.diff".freeze
-
-  def formula(*args, &block)
-    super do
-      url TESTBALL_URL
-      sha256 TESTBALL_SHA256
-      class_eval(&block)
-    end
-  end
-
-  def teardown
-    @_f.clear_cache
-    @_f.patchlist.each { |p| p.clear_cache if p.external? }
-  end
-
-  def assert_patched(formula)
-    shutup do
-      formula.brew do
-        formula.patch
-        s = File.read("libexec/NOOP")
-        refute_includes s, "NOOP", "libexec/NOOP was not patched as expected"
-        assert_includes s, "ABCD", "libexec/NOOP was not patched as expected"
-      end
-    end
-  end
-
-  def assert_sequentially_patched(formula)
-    shutup do
-      formula.brew do
-        formula.patch
-        s = File.read("libexec/NOOP")
-        refute_includes s, "NOOP", "libexec/NOOP was not patched as expected"
-        refute_includes s, "ABCD", "libexec/NOOP was not patched as expected"
-        assert_includes s, "1234", "libexec/NOOP was not patched as expected"
-      end
-    end
-  end
-
-  def assert_missing_apply_fail(formula)
-    assert_raises(MissingApplyError) do
-      shutup do
-        formula.brew do
-          formula.patch
-        end
-      end
-    end
-  end
-
-  def test_single_patch
-    assert_patched formula {
-      def patches
-        PATCH_URL_A
-      end
-    }
-  end
-
-  def test_single_patch_dsl
-    assert_patched formula {
-      patch do
-        url PATCH_URL_A
-        sha256 PATCH_A_SHA256
-      end
-    }
-  end
-
-  def test_single_patch_dsl_with_apply
-    assert_patched formula {
-      patch do
-        url TESTBALL_PATCHES_URL
-        sha256 TESTBALL_PATCHES_SHA256
-        apply APPLY_A
-      end
-    }
-  end
-
-  def test_single_patch_dsl_with_sequential_apply
-    assert_sequentially_patched formula {
-      patch do
-        url TESTBALL_PATCHES_URL
-        sha256 TESTBALL_PATCHES_SHA256
-        apply APPLY_A, APPLY_C
-      end
-    }
-  end
-
-  def test_single_patch_dsl_with_strip
-    assert_patched formula {
-      patch :p1 do
-        url PATCH_URL_A
-        sha256 PATCH_A_SHA256
-      end
-    }
-  end
-
-  def test_single_patch_dsl_with_strip_with_apply
-    assert_patched formula {
-      patch :p1 do
-        url TESTBALL_PATCHES_URL
-        sha256 TESTBALL_PATCHES_SHA256
-        apply APPLY_A
-      end
-    }
-  end
-
-  def test_single_patch_dsl_with_incorrect_strip
-    assert_raises(ErrorDuringExecution) do
-      shutup do
-        formula do
-          patch :p0 do
-            url PATCH_URL_A
-            sha256 PATCH_A_SHA256
-          end
-        end.brew { |f, _staging| f.patch }
-      end
-    end
-  end
-
-  def test_single_patch_dsl_with_incorrect_strip_with_apply
-    assert_raises(ErrorDuringExecution) do
-      shutup do
-        formula do
-          patch :p0 do
-            url TESTBALL_PATCHES_URL
-            sha256 TESTBALL_PATCHES_SHA256
-            apply APPLY_A
-          end
-        end.brew { |f, _staging| f.patch }
-      end
-    end
-  end
-
-  def test_patch_p0_dsl
-    assert_patched formula {
-      patch :p0 do
-        url PATCH_URL_B
-        sha256 PATCH_B_SHA256
-      end
-    }
-  end
-
-  def test_patch_p0_dsl_with_apply
-    assert_patched formula {
-      patch :p0 do
-        url TESTBALL_PATCHES_URL
-        sha256 TESTBALL_PATCHES_SHA256
-        apply APPLY_B
-      end
-    }
-  end
-
-  def test_patch_p0
-    assert_patched formula {
-      def patches
-        { p0: PATCH_URL_B }
-      end
-    }
-  end
-
-  def test_patch_array
-    assert_patched formula {
-      def patches
-        [PATCH_URL_A]
-      end
-    }
-  end
-
-  def test_patch_hash
-    assert_patched formula {
-      def patches
-        { p1: PATCH_URL_A }
-      end
-    }
-  end
-
-  def test_patch_hash_array
-    assert_patched formula {
-      def patches
-        { p1: [PATCH_URL_A] }
-      end
-    }
-  end
-
-  def test_patch_string
-    assert_patched formula { patch PATCH_A_CONTENTS }
-  end
-
-  def test_patch_string_with_strip
-    assert_patched formula { patch :p0, PATCH_B_CONTENTS }
-  end
-
-  def test_patch_data_constant
-    assert_patched formula("test", Pathname.new(__FILE__).expand_path) {
-      def patches
-        :DATA
-      end
-    }
-  end
-
-  def test_single_patch_missing_apply_fail
-    assert_missing_apply_fail formula {
-      def patches
-        TESTBALL_PATCHES_URL
-      end
-    }
-  end
-
-  def test_single_patch_dsl_missing_apply_fail
-    assert_missing_apply_fail formula {
-      patch do
-        url TESTBALL_PATCHES_URL
-        sha256 TESTBALL_PATCHES_SHA256
-      end
-    }
-  end
-
-  def test_single_patch_dsl_with_apply_enoent_fail
-    assert_raises(ErrorDuringExecution) do
-      shutup do
-        formula do
-          patch do
-            url TESTBALL_PATCHES_URL
-            sha256 TESTBALL_PATCHES_SHA256
-            apply "patches/#{APPLY_A}"
-          end
-        end.brew { |f, _staging| f.patch }
-      end
-    end
-  end
-end
-
-__END__
-diff --git a/libexec/NOOP b/libexec/NOOP
-index bfdda4c..e08d8f4 100755
---- a/libexec/NOOP
-+++ b/libexec/NOOP
-@@ -1,2 +1,2 @@
- #!/bin/bash
--echo NOOP
-\ No newline at end of file
-+echo ABCD
-\ No newline at end of file
diff --git a/Library/Homebrew/test/pathname_spec.rb b/Library/Homebrew/test/pathname_spec.rb
new file mode 100644
index 000000000..6e7dc34aa
--- /dev/null
+++ b/Library/Homebrew/test/pathname_spec.rb
@@ -0,0 +1,300 @@
+require "tmpdir"
+require "extend/pathname"
+require "install_renamed"
+
+describe Pathname do
+  include FileUtils
+
+  let(:src) { Pathname.new(Dir.mktmpdir) }
+  let(:dst) { Pathname.new(Dir.mktmpdir) }
+  let(:file) { src/"foo" }
+  let(:dir) { src/"bar" }
+
+  after(:each) { rm_rf [src, dst] }
+
+  describe DiskUsageExtension do
+    before(:each) do
+      mkdir_p dir/"a-directory"
+      touch [dir/".DS_Store", dir/"a-file"]
+      File.truncate(dir/"a-file", 1_048_576)
+      ln_s dir/"a-file", dir/"a-symlink"
+      ln dir/"a-file", dir/"a-hardlink"
+    end
+
+    describe "#file_count" do
+      it "returns the number of files in a directory" do
+        expect(dir.file_count).to eq(3)
+      end
+    end
+
+    describe "#abv" do
+      context "when called on a directory" do
+        it "returns a string with the file count and disk usage" do
+          expect(dir.abv).to eq("3 files, 1MB")
+        end
+      end
+
+      context "when called on a file" do
+        it "returns the disk usage" do
+          expect((dir/"a-file").abv).to eq("1MB")
+        end
+      end
+    end
+  end
+
+  describe "#rmdir_if_possible" do
+    before(:each) { mkdir_p dir }
+
+    it "returns true and removes a directory if it doesn't contain files" do
+      expect(dir.rmdir_if_possible).to be true
+      expect(dir).not_to exist
+    end
+
+    it "returns false and doesn't delete a directory if it contains files" do
+      touch dir/"foo"
+      expect(dir.rmdir_if_possible).to be false
+      expect(dir).to be_a_directory
+    end
+
+    it "ignores .DS_Store files" do
+      touch dir/".DS_Store"
+      expect(dir.rmdir_if_possible).to be true
+      expect(dir).not_to exist
+    end
+  end
+
+  describe "#write" do
+    it "creates a file and writes to it" do
+      expect(file).not_to exist
+      file.write("CONTENT")
+      expect(File.read(file)).to eq("CONTENT")
+    end
+
+    it "raises an error if the file already exists" do
+      touch file
+      expect { file.write("CONTENT") }.to raise_error(RuntimeError)
+    end
+  end
+
+  describe "#append_lines" do
+    it "appends lines to a file" do
+      touch file
+
+      file.append_lines("CONTENT")
+      expect(File.read(file)).to eq <<-EOS.undent
+        CONTENT
+      EOS
+
+      file.append_lines("CONTENTS")
+      expect(File.read(file)).to eq <<-EOS.undent
+        CONTENT
+        CONTENTS
+      EOS
+    end
+
+    it "raises an error if the file does not exist" do
+      expect(file).not_to exist
+      expect { file.append_lines("CONTENT") }.to raise_error(RuntimeError)
+    end
+  end
+
+  describe "#atomic_write" do
+    it "atomically replaces a file" do
+      touch file
+      file.atomic_write("CONTENT")
+      expect(File.read(file)).to eq("CONTENT")
+    end
+
+    it "preserves permissions" do
+      File.open(file, "w", 0100777).close
+      file.atomic_write("CONTENT")
+      expect(file.stat.mode).to eq(0100777 & ~File.umask)
+    end
+
+    it "preserves default permissions" do
+      file.atomic_write("CONTENT")
+      sentinel = file.parent.join("sentinel")
+      touch sentinel
+      expect(file.stat.mode).to eq(sentinel.stat.mode)
+    end
+  end
+
+  describe "#ensure_writable" do
+    it "makes a file writable and restores permissions afterwards" do
+      touch file
+      chmod 0555, file
+      expect(file).not_to be_writable
+      file.ensure_writable do
+        expect(file).to be_writable
+      end
+      expect(file).not_to be_writable
+    end
+  end
+
+  describe "#extname" do
+    it "supports common multi-level archives" do
+      expect(Pathname.new("foo-0.1.tar.gz").extname).to eq(".tar.gz")
+      expect(Pathname.new("foo-0.1.cpio.gz").extname).to eq(".cpio.gz")
+    end
+  end
+
+  describe "#stem" do
+    it "returns the basename without double extensions" do
+      expect(Pathname("foo-0.1.tar.gz").stem).to eq("foo-0.1")
+      expect(Pathname("foo-0.1.cpio.gz").stem).to eq("foo-0.1")
+    end
+  end
+
+  describe "#install" do
+    before(:each) do
+      (src/"a.txt").write "This is sample file a."
+      (src/"b.txt").write "This is sample file b."
+    end
+
+    it "raises an error if the file doesn't exist" do
+      expect { dst.install "non_existent_file" }.to raise_error(Errno::ENOENT)
+    end
+
+    it "installs a file to a directory with its basename" do
+      touch file
+      dst.install(file)
+      expect(dst/file.basename).to exist
+      expect(file).not_to exist
+    end
+
+    it "creates intermediate directories" do
+      touch file
+      expect(dir).not_to be_a_directory
+      dir.install(file)
+      expect(dir).to be_a_directory
+    end
+
+    it "can install a file" do
+      dst.install src/"a.txt"
+      expect(dst/"a.txt").to exist, "a.txt was not installed"
+      expect(dst/"b.txt").not_to exist, "b.txt was installed."
+    end
+
+    it "can install an array of files" do
+      dst.install [src/"a.txt", src/"b.txt"]
+
+      expect(dst/"a.txt").to exist, "a.txt was not installed"
+      expect(dst/"b.txt").to exist, "b.txt was not installed"
+    end
+
+    it "can install a directory" do
+      bin = src/"bin"
+      bin.mkpath
+      mv Dir[src/"*.txt"], bin
+      dst.install bin
+
+      expect(dst/"bin/a.txt").to exist, "a.txt was not installed"
+      expect(dst/"bin/b.txt").to exist, "b.txt was not installed"
+    end
+
+    it "supports renaming files" do
+      dst.install src/"a.txt" => "c.txt"
+
+      expect(dst/"c.txt").to exist, "c.txt was not installed"
+      expect(dst/"a.txt").not_to exist, "a.txt was installed but not renamed"
+      expect(dst/"b.txt").not_to exist, "b.txt was installed"
+    end
+
+    it "supports renaming multiple files" do
+      dst.install(src/"a.txt" => "c.txt", src/"b.txt" => "d.txt")
+
+      expect(dst/"c.txt").to exist, "c.txt was not installed"
+      expect(dst/"d.txt").to exist, "d.txt was not installed"
+      expect(dst/"a.txt").not_to exist, "a.txt was installed but not renamed"
+      expect(dst/"b.txt").not_to exist, "b.txt was installed but not renamed"
+    end
+
+    it "supports renaming directories" do
+      bin = src/"bin"
+      bin.mkpath
+      mv Dir[src/"*.txt"], bin
+      dst.install bin => "libexec"
+
+      expect(dst/"bin").not_to exist, "bin was installed but not renamed"
+      expect(dst/"libexec/a.txt").to exist, "a.txt was not installed"
+      expect(dst/"libexec/b.txt").to exist, "b.txt was not installed"
+    end
+
+    it "can install directories as relative symlinks" do
+      bin = src/"bin"
+      bin.mkpath
+      mv Dir[src/"*.txt"], bin
+      dst.install_symlink bin
+
+      expect(dst/"bin").to be_a_symlink
+      expect(dst/"bin").to be_a_directory
+      expect(dst/"bin/a.txt").to exist
+      expect(dst/"bin/b.txt").to exist
+      expect((dst/"bin").readlink).to be_relative
+    end
+
+    it "can install relative paths as symlinks" do
+      dst.install_symlink "foo" => "bar"
+      expect((dst/"bar").readlink).to eq(Pathname.new("foo"))
+    end
+  end
+
+  describe InstallRenamed do
+    before(:each) do
+      dst.extend(InstallRenamed)
+    end
+
+    it "renames the installed file if it already exists" do
+      file.write "a"
+      dst.install file
+
+      file.write "b"
+      dst.install file
+
+      expect(File.read(dst/file.basename)).to eq("a")
+      expect(File.read(dst/"#{file.basename}.default")).to eq("b")
+    end
+
+    it "renames the installed directory" do
+      file.write "a"
+      dst.install src
+      expect(File.read(dst/src.basename/file.basename)).to eq("a")
+    end
+
+    it "recursively renames directories" do
+      (dst/dir.basename).mkpath
+      (dst/dir.basename/"another_file").write "a"
+      dir.mkpath
+      (dir/"another_file").write "b"
+      dst.install dir
+      expect(File.read(dst/dir.basename/"another_file.default")).to eq("b")
+    end
+  end
+
+  describe "#cp_path_sub" do
+    it "copies a file and replaces the given pattern" do
+      file.write "a"
+      file.cp_path_sub src, dst
+      expect(File.read(dst/file.basename)).to eq("a")
+    end
+
+    it "copies a directory and replaces the given pattern" do
+      dir.mkpath
+      dir.cp_path_sub src, dst
+      expect(dst/dir.basename).to be_a_directory
+    end
+  end
+end
+
+describe FileUtils do
+  let(:dst) { Pathname.new(Dir.mktmpdir) }
+
+  describe "#mkdir" do
+    it "creates indermediate directories" do
+      described_class.mkdir dst/"foo/bar/baz" do
+        expect(dst/"foo/bar/baz").to exist, "foo/bar/baz was not created"
+        expect(dst/"foo/bar/baz").to be_a_directory, "foo/bar/baz was not a directory structure"
+      end
+    end
+  end
+end
diff --git a/Library/Homebrew/test/pathname_test.rb b/Library/Homebrew/test/pathname_test.rb
deleted file mode 100644
index 2f6360719..000000000
--- a/Library/Homebrew/test/pathname_test.rb
+++ /dev/null
@@ -1,267 +0,0 @@
-require "testing_env"
-require "tmpdir"
-require "extend/pathname"
-require "install_renamed"
-
-module PathnameTestExtension
-  include FileUtils
-
-  def setup
-    @src  = Pathname.new(mktmpdir)
-    @dst  = Pathname.new(mktmpdir)
-    @file = @src/"foo"
-    @dir  = @src/"bar"
-  end
-
-  def teardown
-    rmtree(@src)
-    rmtree(@dst)
-  end
-end
-
-class PathnameTests < Homebrew::TestCase
-  include PathnameTestExtension
-
-  def test_disk_usage_extension
-    mkdir_p @dir/"a-directory"
-    touch @dir/".DS_Store"
-    touch @dir/"a-file"
-    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
-    assert_equal "3 files, 1M", @dir.abv
-    assert_equal "1M", (@dir/"a-file").abv
-  end
-
-  def test_rmdir_if_possible
-    mkdir_p @dir
-    touch @dir/"foo"
-
-    assert !@dir.rmdir_if_possible
-    assert_predicate @dir, :directory?
-
-    rm_f @dir/"foo"
-    assert @dir.rmdir_if_possible
-    refute_predicate @dir, :exist?
-  end
-
-  def test_rmdir_if_possible_ignore_ds_store
-    mkdir_p @dir
-    touch @dir/".DS_Store"
-    assert @dir.rmdir_if_possible
-    refute_predicate @dir, :exist?
-  end
-
-  def test_write
-    @file.write("CONTENT")
-    assert_equal "CONTENT", File.read(@file)
-  end
-
-  def test_write_does_not_overwrite
-    touch @file
-    assert_raises(RuntimeError) { @file.write("CONTENT") }
-  end
-
-  def test_append_lines
-    touch @file
-    @file.append_lines("CONTENT")
-    assert_equal "CONTENT\n", File.read(@file)
-    @file.append_lines("CONTENTS")
-    assert_equal "CONTENT\nCONTENTS\n", File.read(@file)
-  end
-
-  def test_append_lines_does_not_create
-    assert_raises(RuntimeError) { @file.append_lines("CONTENT") }
-  end
-
-  def test_atomic_write
-    touch @file
-    @file.atomic_write("CONTENT")
-    assert_equal "CONTENT", File.read(@file)
-  end
-
-  def test_atomic_write_preserves_permissions
-    File.open(@file, "w", 0100777) {}
-    @file.atomic_write("CONTENT")
-    assert_equal 0100777 & ~File.umask, @file.stat.mode
-  end
-
-  def test_atomic_write_preserves_default_permissions
-    @file.atomic_write("CONTENT")
-    sentinel = @file.parent.join("sentinel")
-    touch sentinel
-    assert_equal sentinel.stat.mode, @file.stat.mode
-  end
-
-  def test_ensure_writable
-    touch @file
-    chmod 0555, @file
-    @file.ensure_writable { assert_predicate @file, :writable? }
-    refute_predicate @file, :writable?
-  end
-
-  def test_extname
-    assert_equal ".tar.gz", Pathname("foo-0.1.tar.gz").extname
-    assert_equal ".cpio.gz", Pathname("foo-0.1.cpio.gz").extname
-  end
-
-  def test_stem
-    assert_equal "foo-0.1", Pathname("foo-0.1.tar.gz").stem
-    assert_equal "foo-0.1", Pathname("foo-0.1.cpio.gz").stem
-  end
-
-  def test_install_missing_file
-    assert_raises(Errno::ENOENT) { @dst.install "non_existent_file" }
-  end
-
-  def test_install_removes_original
-    touch @file
-    @dst.install(@file)
-
-    assert_predicate @dst/@file.basename, :exist?
-    refute_predicate @file, :exist?
-  end
-
-  def test_install_creates_intermediate_directories
-    touch @file
-    refute_predicate @dir, :directory?
-    @dir.install(@file)
-    assert_predicate @dir, :directory?
-  end
-
-  def test_install_renamed
-    @dst.extend(InstallRenamed)
-
-    @file.write "a"
-    @dst.install @file
-    @file.write "b"
-    @dst.install @file
-
-    assert_equal "a", File.read(@dst/@file.basename)
-    assert_equal "b", File.read(@dst/"#{@file.basename}.default")
-  end
-
-  def test_install_renamed_directory
-    @dst.extend(InstallRenamed)
-    @file.write "a"
-    @dst.install @src
-    assert_equal "a", File.read(@dst/@src.basename/@file.basename)
-  end
-
-  def test_install_renamed_directory_recursive
-    @dst.extend(InstallRenamed)
-    (@dst/@dir.basename).mkpath
-    (@dst/@dir.basename/"another_file").write "a"
-    @dir.mkpath
-    (@dir/"another_file").write "b"
-    @dst.install @dir
-    assert_equal "b", File.read(@dst/@dir.basename/"another_file.default")
-  end
-
-  def test_cp_path_sub_file
-    @file.write "a"
-    @file.cp_path_sub @src, @dst
-    assert_equal "a", File.read(@dst/"foo")
-  end
-
-  def test_cp_path_sub_directory
-    @dir.mkpath
-    @dir.cp_path_sub @src, @dst
-    assert_predicate @dst/@dir.basename, :directory?
-  end
-end
-
-class PathnameInstallTests < Homebrew::TestCase
-  include PathnameTestExtension
-
-  def setup
-    super
-    (@src/"a.txt").write "This is sample file a."
-    (@src/"b.txt").write "This is sample file b."
-  end
-
-  def test_install
-    @dst.install @src/"a.txt"
-
-    assert_predicate @dst/"a.txt", :exist?, "a.txt was not installed"
-    refute_predicate @dst/"b.txt", :exist?, "b.txt was installed."
-  end
-
-  def test_install_list
-    @dst.install [@src/"a.txt", @src/"b.txt"]
-
-    assert_predicate @dst/"a.txt", :exist?, "a.txt was not installed"
-    assert_predicate @dst/"b.txt", :exist?, "b.txt was not installed"
-  end
-
-  def test_install_glob
-    @dst.install Dir[@src/"*.txt"]
-
-    assert_predicate @dst/"a.txt", :exist?, "a.txt was not installed"
-    assert_predicate @dst/"b.txt", :exist?, "b.txt was not installed"
-  end
-
-  def test_install_directory
-    bin = @src/"bin"
-    bin.mkpath
-    mv Dir[@src/"*.txt"], bin
-    @dst.install bin
-
-    assert_predicate @dst/"bin/a.txt", :exist?, "a.txt was not installed"
-    assert_predicate @dst/"bin/b.txt", :exist?, "b.txt was not installed"
-  end
-
-  def test_install_rename
-    @dst.install @src/"a.txt" => "c.txt"
-
-    assert_predicate @dst/"c.txt", :exist?, "c.txt was not installed"
-    refute_predicate @dst/"a.txt", :exist?, "a.txt was installed but not renamed"
-    refute_predicate @dst/"b.txt", :exist?, "b.txt was installed"
-  end
-
-  def test_install_rename_more
-    @dst.install(@src/"a.txt" => "c.txt", @src/"b.txt" => "d.txt")
-
-    assert_predicate @dst/"c.txt", :exist?, "c.txt was not installed"
-    assert_predicate @dst/"d.txt", :exist?, "d.txt was not installed"
-    refute_predicate @dst/"a.txt", :exist?, "a.txt was installed but not renamed"
-    refute_predicate @dst/"b.txt", :exist?, "b.txt was installed but not renamed"
-  end
-
-  def test_install_rename_directory
-    bin = @src/"bin"
-    bin.mkpath
-    mv Dir[@src/"*.txt"], bin
-    @dst.install bin => "libexec"
-
-    refute_predicate @dst/"bin", :exist?, "bin was installed but not renamed"
-    assert_predicate @dst/"libexec/a.txt", :exist?, "a.txt was not installed"
-    assert_predicate @dst/"libexec/b.txt", :exist?, "b.txt was not installed"
-  end
-
-  def test_install_symlink
-    bin = @src/"bin"
-    bin.mkpath
-    mv Dir[@src/"*.txt"], bin
-    @dst.install_symlink bin
-
-    assert_predicate @dst/"bin", :symlink?
-    assert_predicate @dst/"bin", :directory?
-    assert_predicate @dst/"bin/a.txt", :exist?
-    assert_predicate @dst/"bin/b.txt", :exist?
-    assert_predicate((@dst/"bin").readlink, :relative?)
-  end
-
-  def test_install_relative_symlink
-    @dst.install_symlink "foo" => "bar"
-    assert_equal Pathname.new("foo"), (@dst/"bar").readlink
-  end
-
-  def test_mkdir_creates_intermediate_directories
-    mkdir @dst/"foo/bar/baz" do
-      assert_predicate @dst/"foo/bar/baz", :exist?, "foo/bar/baz was not created"
-      assert_predicate @dst/"foo/bar/baz", :directory?, "foo/bar/baz was not a directory structure"
-    end
-  end
-end
diff --git a/Library/Homebrew/test/pin_unpin_test.rb b/Library/Homebrew/test/pin_unpin_test.rb
deleted file mode 100644
index 65fb9e4da..000000000
--- a/Library/Homebrew/test/pin_unpin_test.rb
+++ /dev/null
@@ -1,18 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestPinUnpin < IntegrationCommandTestCase
-  def test_pin_unpin
-    setup_test_formula "testball"
-    (HOMEBREW_CELLAR/"testball/0.0.1/foo").mkpath
-
-    cmd("pin", "testball")
-    cmd("upgrade")
-    refute((HOMEBREW_CELLAR/"testball/0.1").directory?,
-      "The latest version directory should NOT be created")
-
-    cmd("unpin", "testball")
-    cmd("upgrade")
-    assert((HOMEBREW_CELLAR/"testball/0.1").directory?,
-      "The latest version directory should be created")
-  end
-end
diff --git a/Library/Homebrew/test/pkg_version_spec.rb b/Library/Homebrew/test/pkg_version_spec.rb
new file mode 100644
index 000000000..b1cceb32c
--- /dev/null
+++ b/Library/Homebrew/test/pkg_version_spec.rb
@@ -0,0 +1,81 @@
+require "pkg_version"
+
+describe PkgVersion do
+  describe "::parse" do
+    it "parses versions from a string" do
+      expect(described_class.parse("1.0_1")).to eq(described_class.new(Version.create("1.0"), 1))
+      expect(described_class.parse("1.0_1")).to eq(described_class.new(Version.create("1.0"), 1))
+      expect(described_class.parse("1.0")).to eq(described_class.new(Version.create("1.0"), 0))
+      expect(described_class.parse("1.0_0")).to eq(described_class.new(Version.create("1.0"), 0))
+      expect(described_class.parse("2.1.4_0")).to eq(described_class.new(Version.create("2.1.4"), 0))
+      expect(described_class.parse("1.0.1e_1")).to eq(described_class.new(Version.create("1.0.1e"), 1))
+    end
+  end
+
+  specify "#==" do
+    expect(described_class.parse("1.0_0")).to be == described_class.parse("1.0")
+    expect(described_class.parse("1.0_1")).to be == described_class.parse("1.0_1")
+  end
+
+  describe "#>" do
+    it "returns true if the left version is bigger than the right" do
+      expect(described_class.parse("1.1")).to be > described_class.parse("1.0_1")
+    end
+
+    it "returns true if the left version is HEAD" do
+      expect(described_class.parse("HEAD")).to be > described_class.parse("1.0")
+    end
+
+    it "raises an error if the other side isn't of the same class" do
+      expect {
+        described_class.new(Version.create("1.0"), 0) > Object.new
+      }.to raise_error(ArgumentError)
+    end
+
+    it "is not compatible with Version" do
+      expect {
+        described_class.new(Version.create("1.0"), 0) > Version.create("1.0")
+      }.to raise_error(ArgumentError)
+    end
+  end
+
+  describe "#<" do
+    it "returns true if the left version is smaller than the right" do
+      expect(described_class.parse("1.0_1")).to be < described_class.parse("2.0_1")
+    end
+
+    it "returns true if the right version is HEAD" do
+      expect(described_class.parse("1.0")).to be < described_class.parse("HEAD")
+    end
+  end
+
+  describe "#<=>" do
+    it "returns nil if the comparison fails" do
+      expect(described_class.new(Version.create("1.0"), 0) <=> Object.new).to be nil
+    end
+  end
+
+  describe "#to_s" do
+    it "returns a string of the form 'version_revision'" do
+      expect(described_class.new(Version.create("1.0"), 0).to_s).to eq("1.0")
+      expect(described_class.new(Version.create("1.0"), 1).to_s).to eq("1.0_1")
+      expect(described_class.new(Version.create("1.0"), 0).to_s).to eq("1.0")
+      expect(described_class.new(Version.create("1.0"), 0).to_s).to eq("1.0")
+      expect(described_class.new(Version.create("HEAD"), 1).to_s).to eq("HEAD_1")
+      expect(described_class.new(Version.create("HEAD-ffffff"), 1).to_s).to eq("HEAD-ffffff_1")
+    end
+  end
+
+  describe "#hash" do
+    let(:p1) { described_class.new(Version.create("1.0"), 1) }
+    let(:p2) { described_class.new(Version.create("1.0"), 1) }
+    let(:p3) { described_class.new(Version.create("1.1"), 1) }
+    let(:p4) { described_class.new(Version.create("1.0"), 0) }
+
+    it "returns a hash based on the version and revision" do
+      expect(p1.hash).to eq(p2.hash)
+      expect(p1.hash).not_to eq(p3.hash)
+      expect(p1.hash).not_to eq(p4.hash)
+    end
+  end
+end
diff --git a/Library/Homebrew/test/pkg_version_test.rb b/Library/Homebrew/test/pkg_version_test.rb
deleted file mode 100644
index ff7896f8b..000000000
--- a/Library/Homebrew/test/pkg_version_test.rb
+++ /dev/null
@@ -1,51 +0,0 @@
-require "testing_env"
-require "pkg_version"
-
-class PkgVersionTests < Homebrew::TestCase
-  def v(version)
-    PkgVersion.parse(version)
-  end
-
-  def test_parse
-    assert_equal PkgVersion.new(Version.create("1.0"), 1), PkgVersion.parse("1.0_1")
-    assert_equal PkgVersion.new(Version.create("1.0"), 1), PkgVersion.parse("1.0_1")
-    assert_equal PkgVersion.new(Version.create("1.0"), 0), PkgVersion.parse("1.0")
-    assert_equal PkgVersion.new(Version.create("1.0"), 0), PkgVersion.parse("1.0_0")
-    assert_equal PkgVersion.new(Version.create("2.1.4"), 0), PkgVersion.parse("2.1.4_0")
-    assert_equal PkgVersion.new(Version.create("1.0.1e"), 1), PkgVersion.parse("1.0.1e_1")
-  end
-
-  def test_comparison
-    assert_operator v("1.0_0"), :==, v("1.0")
-    assert_operator v("1.0_1"), :==, v("1.0_1")
-    assert_operator v("1.1"), :>, v("1.0_1")
-    assert_operator v("1.0_0"), :==, v("1.0")
-    assert_operator v("1.0_1"), :<, v("2.0_1")
-    assert_operator v("HEAD"), :>, v("1.0")
-    assert_operator v("1.0"), :<, v("HEAD")
-
-    v = PkgVersion.new(Version.create("1.0"), 0)
-    assert_nil v <=> Object.new
-    assert_raises(ArgumentError) { v > Object.new }
-    assert_raises(ArgumentError) { v > Version.create("1.0") }
-  end
-
-  def test_to_s
-    assert_equal "1.0", PkgVersion.new(Version.create("1.0"), 0).to_s
-    assert_equal "1.0_1", PkgVersion.new(Version.create("1.0"), 1).to_s
-    assert_equal "1.0", PkgVersion.new(Version.create("1.0"), 0).to_s
-    assert_equal "1.0", PkgVersion.new(Version.create("1.0"), 0).to_s
-    assert_equal "HEAD_1", PkgVersion.new(Version.create("HEAD"), 1).to_s
-    assert_equal "HEAD-ffffff_1", PkgVersion.new(Version.create("HEAD-ffffff"), 1).to_s
-  end
-
-  def test_hash
-    p1 = PkgVersion.new(Version.create("1.0"), 1)
-    p2 = PkgVersion.new(Version.create("1.0"), 1)
-    p3 = PkgVersion.new(Version.create("1.1"), 1)
-    p4 = PkgVersion.new(Version.create("1.0"), 0)
-    assert_equal p1.hash, p2.hash
-    refute_equal p1.hash, p3.hash
-    refute_equal p1.hash, p4.hash
-  end
-end
diff --git a/Library/Homebrew/test/prefix_formula_test.rb b/Library/Homebrew/test/prefix_formula_test.rb
deleted file mode 100644
index eb5970d3e..000000000
--- a/Library/Homebrew/test/prefix_formula_test.rb
+++ /dev/null
@@ -1,8 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestPrefixFormula < IntegrationCommandTestCase
-  def test_prefix_formula
-    assert_match "#{HOMEBREW_CELLAR}/testball",
-                 cmd("--prefix", testball)
-  end
-end
diff --git a/Library/Homebrew/test/prefix_test.rb b/Library/Homebrew/test/prefix_test.rb
deleted file mode 100644
index a3ae75542..000000000
--- a/Library/Homebrew/test/prefix_test.rb
+++ /dev/null
@@ -1,8 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestPrefix < IntegrationCommandTestCase
-  def test_prefix
-    assert_equal HOMEBREW_PREFIX.to_s,
-                 cmd("--prefix")
-  end
-end
diff --git a/Library/Homebrew/test/prune_test.rb b/Library/Homebrew/test/prune_test.rb
deleted file mode 100644
index 8fa5df7b7..000000000
--- a/Library/Homebrew/test/prune_test.rb
+++ /dev/null
@@ -1,21 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestPrune < IntegrationCommandTestCase
-  def test_prune
-    share = (HOMEBREW_PREFIX/"share")
-
-    (share/"pruneable/directory/here").mkpath
-    (share/"notpruneable/file").write "I'm here"
-    FileUtils.ln_s "/i/dont/exist/no/really/i/dont", share/"pruneable_symlink"
-
-    assert_match %r{Would remove \(empty directory\): .*/pruneable/directory/here},
-      cmd("prune", "--dry-run")
-    assert_match "Pruned 1 symbolic links and 3 directories",
-      cmd("prune")
-    refute((share/"pruneable").directory?)
-    assert((share/"notpruneable").directory?)
-    refute((share/"pruneable_symlink").symlink?)
-
-    assert_match "Nothing pruned", cmd("prune", "--verbose")
-  end
-end
diff --git a/Library/Homebrew/test/pull_offline_test.rb b/Library/Homebrew/test/pull_offline_test.rb
deleted file mode 100644
index c9d46cd74..000000000
--- a/Library/Homebrew/test/pull_offline_test.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestPullOffline < IntegrationCommandTestCase
-  def test_pull_offline
-    assert_match "You meant `git pull --rebase`.", cmd_fail("pull", "--rebase")
-    assert_match "This command requires at least one argument", cmd_fail("pull")
-    assert_match "Not a GitHub pull request or commit",
-      cmd_fail("pull", "0")
-  end
-end
diff --git a/Library/Homebrew/test/pull_test.rb b/Library/Homebrew/test/pull_test.rb
deleted file mode 100644
index 445d73cb1..000000000
--- a/Library/Homebrew/test/pull_test.rb
+++ /dev/null
@@ -1,27 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestPull < IntegrationCommandTestCase
-  def test_pull
-    skip "Requires network connection" if ENV["HOMEBREW_NO_GITHUB_API"]
-
-    core_tap = CoreTap.new
-    core_tap.path.cd do
-      shutup do
-        system "git", "init"
-        system "git", "checkout", "-b", "new-branch"
-      end
-    end
-
-    assert_match "Testing URLs require `--bottle`!",
-      cmd_fail("pull", "https://bot.brew.sh/job/Homebrew\%20Testing/1028/")
-    assert_match "Current branch is new-branch",
-      cmd_fail("pull", "1")
-    assert_match "No changed formulae found to bump",
-      cmd_fail("pull", "--bump", "8")
-    assert_match "Can only bump one changed formula",
-      cmd_fail("pull", "--bump",
-        "https://api.github.com/repos/Homebrew/homebrew-core/pulls/122")
-    assert_match "Patch failed to apply",
-      cmd_fail("pull", "https://github.com/Homebrew/homebrew-core/pull/1")
-  end
-end
diff --git a/Library/Homebrew/test/readall_test.rb b/Library/Homebrew/test/readall_test.rb
deleted file mode 100644
index 3eec79dd8..000000000
--- a/Library/Homebrew/test/readall_test.rb
+++ /dev/null
@@ -1,12 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestReadall < IntegrationCommandTestCase
-  def test_readall
-    formula_file = setup_test_formula "testball"
-    alias_file = CoreTap.new.alias_dir/"foobar"
-    alias_file.parent.mkpath
-    FileUtils.ln_s formula_file, alias_file
-    cmd("readall", "--aliases", "--syntax")
-    cmd("readall", "homebrew/core")
-  end
-end
diff --git a/Library/Homebrew/test/reinstall_pinned_test.rb b/Library/Homebrew/test/reinstall_pinned_test.rb
deleted file mode 100644
index 80f5518ea..000000000
--- a/Library/Homebrew/test/reinstall_pinned_test.rb
+++ /dev/null
@@ -1,15 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestReinstallPinned < IntegrationCommandTestCase
-  def test_reinstall_pinned
-    setup_test_formula "testball"
-
-    HOMEBREW_CELLAR.join("testball/0.1").mkpath
-    HOMEBREW_PINNED_KEGS.mkpath
-    FileUtils.ln_s HOMEBREW_CELLAR.join("testball/0.1"), HOMEBREW_PINNED_KEGS/"testball"
-
-    assert_match "testball is pinned. You must unpin it to reinstall.", cmd("reinstall", "testball")
-
-    HOMEBREW_PINNED_KEGS.rmtree
-  end
-end
diff --git a/Library/Homebrew/test/reinstall_test.rb b/Library/Homebrew/test/reinstall_test.rb
deleted file mode 100644
index 613c06188..000000000
--- a/Library/Homebrew/test/reinstall_test.rb
+++ /dev/null
@@ -1,15 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestReinstall < IntegrationCommandTestCase
-  def test_reinstall
-    setup_test_formula "testball"
-
-    cmd("install", "testball", "--with-foo")
-    foo_dir = HOMEBREW_CELLAR/"testball/0.1/foo"
-    assert foo_dir.exist?
-    foo_dir.rmtree
-    assert_match "Reinstalling testball --with-foo",
-      cmd("reinstall", "testball")
-    assert foo_dir.exist?
-  end
-end
diff --git a/Library/Homebrew/test/repository_test.rb b/Library/Homebrew/test/repository_test.rb
deleted file mode 100644
index 77967a58d..000000000
--- a/Library/Homebrew/test/repository_test.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestRepository < IntegrationCommandTestCase
-  def test_repository
-    assert_match HOMEBREW_REPOSITORY.to_s,
-                 cmd("--repository")
-    assert_match "#{HOMEBREW_LIBRARY}/Taps/foo/homebrew-bar",
-                 cmd("--repository", "foo/bar")
-  end
-end
diff --git a/Library/Homebrew/test/requirement_spec.rb b/Library/Homebrew/test/requirement_spec.rb
new file mode 100644
index 000000000..110a7ac4f
--- /dev/null
+++ b/Library/Homebrew/test/requirement_spec.rb
@@ -0,0 +1,288 @@
+require "extend/ENV"
+require "requirement"
+
+RSpec::Matchers.alias_matcher :have_a_default_formula, :be_a_default_formula
+RSpec::Matchers.alias_matcher :be_a_build_requirement, :be_a_build
+
+describe Requirement do
+  subject { klass.new }
+
+  let(:klass) { Class.new(described_class) }
+
+  describe "#tags" do
+    subject { described_class.new(tags) }
+
+    context "single tag" do
+      let(:tags) { ["bar"] }
+
+      its(:tags) { are_expected.to eq(tags) }
+    end
+
+    context "multiple tags" do
+      let(:tags) { ["bar", "baz"] }
+
+      its(:tags) { are_expected.to eq(tags) }
+    end
+
+    context "symbol tags" do
+      let(:tags) { [:build] }
+
+      its(:tags) { are_expected.to eq(tags) }
+    end
+
+    context "symbol and string tags" do
+      let(:tags) { [:build, "bar"] }
+
+      its(:tags) { are_expected.to eq(tags) }
+    end
+  end
+
+  describe "#fatal?" do
+    context "#fatal true is specified" do
+      let(:klass) do
+        Class.new(described_class) do
+          fatal true
+        end
+      end
+
+      it { is_expected.to be_fatal }
+    end
+
+    context "#fatal is ommitted" do
+      it { is_expected.not_to be_fatal }
+    end
+  end
+
+  describe "#satisfied?" do
+    context "#satisfy with block and build_env returns true" do
+      let(:klass) do
+        Class.new(described_class) do
+          satisfy(build_env: false) do
+            true
+          end
+        end
+      end
+
+      it { is_expected.to be_satisfied }
+    end
+
+    context "#satisfy with block and build_env returns false" do
+      let(:klass) do
+        Class.new(described_class) do
+          satisfy(build_env: false) do
+            false
+          end
+        end
+      end
+
+      it { is_expected.not_to be_satisfied }
+    end
+
+    context "#satisfy returns true" do
+      let(:klass) do
+        Class.new(described_class) do
+          satisfy true
+        end
+      end
+
+      it { is_expected.to be_satisfied }
+    end
+
+    context "#satisfy returns false" do
+      let(:klass) do
+        Class.new(described_class) do
+          satisfy false
+        end
+      end
+
+      it { is_expected.not_to be_satisfied }
+    end
+
+    context "#satisfy with block returning true and without :build_env" do
+      let(:klass) do
+        Class.new(described_class) do
+          satisfy do
+            true
+          end
+        end
+      end
+
+      it "sets up build environment" do
+        expect(ENV).to receive(:with_build_environment).and_call_original
+        subject.satisfied?
+      end
+    end
+
+    context "#satisfy with block returning true and :build_env set to false" do
+      let(:klass) do
+        Class.new(described_class) do
+          satisfy(build_env: false) do
+            true
+          end
+        end
+      end
+
+      it "skips setting up build environment" do
+        expect(ENV).not_to receive(:with_build_environment)
+        subject.satisfied?
+      end
+    end
+
+    context "#satisfy with block returning path and without :build_env" do
+      let(:klass) do
+        Class.new(described_class) do
+          satisfy do
+            Pathname.new("/foo/bar/baz")
+          end
+        end
+      end
+
+      it "infers path from #satisfy result" do
+        expect(ENV).to receive(:append_path).with("PATH", Pathname.new("/foo/bar"))
+        subject.satisfied?
+        subject.modify_build_environment
+      end
+    end
+  end
+
+  describe "#build?" do
+    context "#build true is specified" do
+      let(:klass) do
+        Class.new(described_class) do
+          build true
+        end
+      end
+
+      it { is_expected.to be_a_build_requirement }
+    end
+
+    context "#build ommitted" do
+      it { is_expected.not_to be_a_build_requirement }
+    end
+  end
+
+  describe "#name and #option_names" do
+    let(:const) { :FooRequirement }
+    let(:klass) { self.class.const_get(const) }
+
+    before(:each) do
+      self.class.const_set(const, Class.new(described_class))
+    end
+
+    after(:each) do
+      self.class.send(:remove_const, const)
+    end
+
+    its(:name) { is_expected.to eq("foo") }
+    its(:option_names) { are_expected.to eq(["foo"]) }
+  end
+
+  describe "#default_formula?" do
+    context "#default_formula specified" do
+      let(:klass) do
+        Class.new(described_class) do
+          default_formula "foo"
+        end
+      end
+
+      it { is_expected.to have_a_default_formula }
+    end
+
+    context "#default_formula ommitted" do
+      it { is_expected.not_to have_a_default_formula }
+    end
+  end
+
+  describe "#to_dependency" do
+    let(:klass) do
+      Class.new(described_class) do
+        default_formula "foo"
+      end
+    end
+
+    it "returns a Dependency for its default Formula" do
+      expect(subject.to_dependency).to eq(Dependency.new("foo"))
+    end
+
+    context "#modify_build_environment" do
+      context "with error" do
+        let(:klass) do
+          Class.new(described_class) do
+            class ModifyBuildEnvironmentError < StandardError; end
+
+            default_formula "foo"
+
+            satisfy do
+              true
+            end
+
+            env do
+              raise ModifyBuildEnvironmentError
+            end
+          end
+        end
+
+        it "raises an error" do
+          expect {
+            subject.to_dependency.modify_build_environment
+          }.to raise_error(klass.const_get(:ModifyBuildEnvironmentError))
+        end
+      end
+    end
+  end
+
+  describe "#modify_build_environment" do
+    context "without env proc" do
+      let(:klass) { Class.new(described_class) }
+
+      it "returns nil" do
+        expect(subject.modify_build_environment).to be nil
+      end
+    end
+  end
+
+  describe "#eql? and #==" do
+    subject { described_class.new }
+
+    it "returns true if the names and tags are equal" do
+      other = described_class.new
+
+      expect(subject).to eql(other)
+      expect(subject).to eq(other)
+    end
+
+    it "returns false if names differ" do
+      other = described_class.new
+      allow(other).to receive(:name).and_return("foo")
+      expect(subject).not_to eql(other)
+      expect(subject).not_to eq(other)
+    end
+
+    it "returns false if tags differ" do
+      other = described_class.new([:optional])
+
+      expect(subject).not_to eql(other)
+      expect(subject).not_to eq(other)
+    end
+  end
+
+  describe "#hash" do
+    subject { described_class.new }
+
+    it "is equal if names and tags are equal" do
+      other = described_class.new
+      expect(subject.hash).to eq(other.hash)
+    end
+
+    it "differs if names differ" do
+      other = described_class.new
+      allow(other).to receive(:name).and_return("foo")
+      expect(subject.hash).not_to eq(other.hash)
+    end
+
+    it "differs if tags differ" do
+      other = described_class.new([:optional])
+      expect(subject.hash).not_to eq(other.hash)
+    end
+  end
+end
diff --git a/Library/Homebrew/test/requirement_test.rb b/Library/Homebrew/test/requirement_test.rb
deleted file mode 100644
index 580d42bfa..000000000
--- a/Library/Homebrew/test/requirement_test.rb
+++ /dev/null
@@ -1,152 +0,0 @@
-require "testing_env"
-require "requirement"
-
-class RequirementTests < Homebrew::TestCase
-  class TestRequirement < Requirement; end
-
-  def test_accepts_single_tag
-    dep = Requirement.new(%w[bar])
-    assert_equal %w[bar], dep.tags
-  end
-
-  def test_accepts_multiple_tags
-    dep = Requirement.new(%w[bar baz])
-    assert_equal %w[bar baz].sort, dep.tags.sort
-  end
-
-  def test_option_names
-    dep = TestRequirement.new
-    assert_equal %w[test], dep.option_names
-  end
-
-  def test_preserves_symbol_tags
-    dep = Requirement.new([:build])
-    assert_equal [:build], dep.tags
-  end
-
-  def test_accepts_symbol_and_string_tags
-    dep = Requirement.new([:build, "bar"])
-    assert_equal [:build, "bar"], dep.tags
-  end
-
-  def test_dsl_fatal
-    req = Class.new(Requirement) { fatal true }.new
-    assert_predicate req, :fatal?
-  end
-
-  def test_satisfy_true
-    req = Class.new(Requirement) do
-      satisfy(build_env: false) { true }
-    end.new
-    assert_predicate req, :satisfied?
-  end
-
-  def test_satisfy_false
-    req = Class.new(Requirement) do
-      satisfy(build_env: false) { false }
-    end.new
-    refute_predicate req, :satisfied?
-  end
-
-  def test_satisfy_with_boolean
-    req = Class.new(Requirement) do
-      satisfy true
-    end.new
-    assert_predicate req, :satisfied?
-  end
-
-  def test_satisfy_sets_up_build_env_by_default
-    req = Class.new(Requirement) do
-      satisfy { true }
-    end.new
-
-    ENV.expects(:with_build_environment).yields.returns(true)
-
-    assert_predicate req, :satisfied?
-  end
-
-  def test_satisfy_build_env_can_be_disabled
-    req = Class.new(Requirement) do
-      satisfy(build_env: false) { true }
-    end.new
-
-    ENV.expects(:with_build_environment).never
-
-    assert_predicate req, :satisfied?
-  end
-
-  def test_infers_path_from_satisfy_result
-    which_path = Pathname.new("/foo/bar/baz")
-    req = Class.new(Requirement) do
-      satisfy { which_path }
-    end.new
-
-    ENV.expects(:with_build_environment).yields.returns(which_path)
-    ENV.expects(:append_path).with("PATH", which_path.parent)
-
-    req.satisfied?
-    req.modify_build_environment
-  end
-
-  def test_dsl_build
-    req = Class.new(Requirement) { build true }.new
-    assert_predicate req, :build?
-  end
-
-  def test_infer_name_from_class
-    const = :FooRequirement
-    klass = self.class
-
-    klass.const_set(const, Class.new(Requirement))
-
-    begin
-      assert_equal "foo", klass.const_get(const).new.name
-    ensure
-      klass.send(:remove_const, const)
-    end
-  end
-
-  def test_dsl_default_formula
-    req = Class.new(Requirement) { default_formula "foo" }.new
-    assert_predicate req, :default_formula?
-  end
-
-  def test_to_dependency
-    req = Class.new(Requirement) { default_formula "foo" }.new
-    assert_equal Dependency.new("foo"), req.to_dependency
-  end
-
-  def test_to_dependency_calls_requirement_modify_build_environment
-    error = Class.new(StandardError)
-
-    req = Class.new(Requirement) do
-      default_formula "foo"
-      satisfy { true }
-      env { raise error }
-    end.new
-
-    assert_raises(error) do
-      req.to_dependency.modify_build_environment
-    end
-  end
-
-  def test_modify_build_environment_without_env_proc
-    assert_nil Class.new(Requirement).new.modify_build_environment
-  end
-
-  def test_eql
-    a = Requirement.new
-    b = Requirement.new
-    assert_equal a, b
-    assert_eql a, b
-    assert_equal a.hash, b.hash
-  end
-
-  def test_not_eql
-    a = Requirement.new([:optional])
-    b = Requirement.new
-    refute_equal a, b
-    refute_eql a, b
-    refute_equal a.hash, b.hash
-  end
-end
diff --git a/Library/Homebrew/test/resource_spec.rb b/Library/Homebrew/test/resource_spec.rb
new file mode 100644
index 000000000..6a0419538
--- /dev/null
+++ b/Library/Homebrew/test/resource_spec.rb
@@ -0,0 +1,147 @@
+require "resource"
+
+describe Resource do
+  subject { described_class.new("test") }
+
+  describe "#url" do
+    it "sets the URL" do
+      subject.url("foo")
+      expect(subject.url).to eq("foo")
+    end
+
+    it "can set the URL with specifications" do
+      subject.url("foo", branch: "master")
+      expect(subject.url).to eq("foo")
+      expect(subject.specs).to eq(branch: "master")
+    end
+
+    it "can set the URL with a custom download strategy class" do
+      strategy = Class.new(AbstractDownloadStrategy)
+      subject.url("foo", using: strategy)
+      expect(subject.url).to eq("foo")
+      expect(subject.download_strategy).to eq(strategy)
+    end
+
+    it "can set the URL with specifications and a custom download strategy class" do
+      strategy = Class.new(AbstractDownloadStrategy)
+      subject.url("foo", using: strategy, branch: "master")
+      expect(subject.url).to eq("foo")
+      expect(subject.specs).to eq(branch: "master")
+      expect(subject.download_strategy).to eq(strategy)
+    end
+
+    it "can set the URL with a custom download strategy symbol" do
+      subject.url("foo", using: :git)
+      expect(subject.url).to eq("foo")
+      expect(subject.download_strategy).to eq(GitDownloadStrategy)
+    end
+
+    it "raises an error if the download strategy class is unkown" do
+      expect { subject.url("foo", using: Class.new) }.to raise_error(TypeError)
+    end
+
+    it "does not mutate the specifications hash" do
+      specs = { using: :git, branch: "master" }
+      subject.url("foo", specs)
+      expect(subject.specs).to eq(branch: "master")
+      expect(subject.using).to eq(:git)
+      expect(specs).to eq(using: :git, branch: "master")
+    end
+  end
+
+  describe "#version" do
+    it "sets the version" do
+      subject.version("1.0")
+      expect(subject.version).to eq(Version.parse("1.0"))
+      expect(subject.version).not_to be_detected_from_url
+    end
+
+    it "can detect the version from a URL" do
+      subject.url("http://example.com/foo-1.0.tar.gz")
+      expect(subject.version).to eq(Version.parse("1.0"))
+      expect(subject.version).to be_detected_from_url
+    end
+
+    it "can set the version with a scheme" do
+      klass = Class.new(Version)
+      subject.version klass.new("1.0")
+      expect(subject.version).to eq(Version.parse("1.0"))
+      expect(subject.version).to be_a(klass)
+    end
+
+    it "can set the version from a tag" do
+      subject.url("http://example.com/foo-1.0.tar.gz", tag: "v1.0.2")
+      expect(subject.version).to eq(Version.parse("1.0.2"))
+      expect(subject.version).to be_detected_from_url
+    end
+
+    it "rejects non-string versions" do
+      expect { subject.version(1) }.to raise_error(TypeError)
+      expect { subject.version(2.0) }.to raise_error(TypeError)
+      expect { subject.version(Object.new) }.to raise_error(TypeError)
+    end
+
+    it "returns nil if unset" do
+      expect(subject.version).to be nil
+    end
+  end
+
+  describe "#mirrors" do
+    it "is empty by defaults" do
+      expect(subject.mirrors).to be_empty
+    end
+
+    it "returns an array of mirrors added with #mirror" do
+      subject.mirror("foo")
+      subject.mirror("bar")
+      expect(subject.mirrors).to eq(%w[foo bar])
+    end
+  end
+
+  describe "#checksum" do
+    it "returns nil if unset" do
+      expect(subject.checksum).to be nil
+    end
+
+    it "returns the checksum set with #sha256" do
+      subject.sha256(TEST_SHA256)
+      expect(subject.checksum).to eq(Checksum.new(:sha256, TEST_SHA256))
+    end
+  end
+
+  describe "#download_strategy" do
+    it "returns the download strategy" do
+      strategy = Object.new
+      expect(DownloadStrategyDetector)
+        .to receive(:detect).with("foo", nil).and_return(strategy)
+      subject.url("foo")
+      expect(subject.download_strategy).to eq(strategy)
+    end
+  end
+
+  specify "#verify_download_integrity_missing" do
+    fn = Pathname.new("test")
+
+    allow(fn).to receive(:file?).and_return(true)
+    expect(fn).to receive(:verify_checksum).and_raise(ChecksumMissingError)
+    expect(fn).to receive(:sha256)
+
+    shutup do
+      subject.verify_download_integrity(fn)
+    end
+  end
+
+  specify "#verify_download_integrity_mismatch" do
+    fn = double(file?: true)
+    checksum = subject.sha256(TEST_SHA256)
+
+    expect(fn).to receive(:verify_checksum).with(checksum)
+      .and_raise(ChecksumMismatchError.new(fn, checksum, Object.new))
+
+    shutup do
+      expect {
+        subject.verify_download_integrity(fn)
+      }.to raise_error(ChecksumMismatchError)
+    end
+  end
+end
diff --git a/Library/Homebrew/test/resource_test.rb b/Library/Homebrew/test/resource_test.rb
deleted file mode 100644
index c1b526cb2..000000000
--- a/Library/Homebrew/test/resource_test.rb
+++ /dev/null
@@ -1,132 +0,0 @@
-require "testing_env"
-require "resource"
-
-class ResourceTests < Homebrew::TestCase
-  def setup
-    @resource = Resource.new("test")
-  end
-
-  def test_url
-    @resource.url("foo")
-    assert_equal "foo", @resource.url
-  end
-
-  def test_url_with_specs
-    @resource.url("foo", branch: "master")
-    assert_equal "foo", @resource.url
-    assert_equal({ branch: "master" }, @resource.specs)
-  end
-
-  def test_url_with_custom_download_strategy_class
-    strategy = Class.new(AbstractDownloadStrategy)
-    @resource.url("foo", using: strategy)
-    assert_equal "foo", @resource.url
-    assert_equal strategy, @resource.download_strategy
-  end
-
-  def test_url_with_specs_and_download_strategy
-    strategy = Class.new(AbstractDownloadStrategy)
-    @resource.url("foo", using: strategy, branch: "master")
-    assert_equal "foo", @resource.url
-    assert_equal({ branch: "master" }, @resource.specs)
-    assert_equal strategy, @resource.download_strategy
-  end
-
-  def test_url_with_custom_download_strategy_symbol
-    @resource.url("foo", using: :git)
-    assert_equal "foo", @resource.url
-    assert_equal GitDownloadStrategy, @resource.download_strategy
-  end
-
-  def test_raises_for_unknown_download_strategy_class
-    assert_raises(TypeError) { @resource.url("foo", using: Class.new) }
-  end
-
-  def test_does_not_mutate_specs_hash
-    specs = { using: :git, branch: "master" }
-    @resource.url("foo", specs)
-    assert_equal({ branch: "master" }, @resource.specs)
-    assert_equal(:git, @resource.using)
-    assert_equal({ using: :git, branch: "master" }, specs)
-  end
-
-  def test_version
-    @resource.version("1.0")
-    assert_version_equal "1.0", @resource.version
-    refute_predicate @resource.version, :detected_from_url?
-  end
-
-  def test_version_from_url
-    @resource.url("http://example.com/foo-1.0.tar.gz")
-    assert_version_equal "1.0", @resource.version
-    assert_predicate @resource.version, :detected_from_url?
-  end
-
-  def test_version_with_scheme
-    klass = Class.new(Version)
-    @resource.version klass.new("1.0")
-    assert_version_equal "1.0", @resource.version
-    assert_instance_of klass, @resource.version
-  end
-
-  def test_version_from_tag
-    @resource.url("http://example.com/foo-1.0.tar.gz", tag: "v1.0.2")
-    assert_version_equal "1.0.2", @resource.version
-    assert_predicate @resource.version, :detected_from_url?
-  end
-
-  def test_rejects_non_string_versions
-    assert_raises(TypeError) { @resource.version(1) }
-    assert_raises(TypeError) { @resource.version(2.0) }
-    assert_raises(TypeError) { @resource.version(Object.new) }
-  end
-
-  def test_version_when_url_is_not_set
-    assert_nil @resource.version
-  end
-
-  def test_mirrors
-    assert_empty @resource.mirrors
-    @resource.mirror("foo")
-    @resource.mirror("bar")
-    assert_equal %w[foo bar], @resource.mirrors
-  end
-
-  def test_checksum_setters
-    assert_nil @resource.checksum
-    @resource.sha256(TEST_SHA256)
-    assert_equal Checksum.new(:sha256, TEST_SHA256), @resource.checksum
-  end
-
-  def test_download_strategy
-    strategy = Object.new
-    DownloadStrategyDetector
-      .expects(:detect).with("foo", nil).returns(strategy)
-    @resource.url("foo")
-    assert_equal strategy, @resource.download_strategy
-  end
-
-  def test_verify_download_integrity_missing
-    fn = Pathname.new("test")
-
-    fn.stubs(file?: true)
-    fn.expects(:verify_checksum).raises(ChecksumMissingError)
-    fn.expects(:sha256)
-
-    shutup { @resource.verify_download_integrity(fn) }
-  end
-
-  def test_verify_download_integrity_mismatch
-    fn = stub(file?: true)
-    checksum = @resource.sha256(TEST_SHA256)
-
-    fn.expects(:verify_checksum).with(checksum)
-      .raises(ChecksumMismatchError.new(fn, checksum, Object.new))
-
-    shutup do
-      assert_raises(ChecksumMismatchError) do
-        @resource.verify_download_integrity(fn)
-      end
-    end
-  end
-end
diff --git a/Library/Homebrew/test/sandbox_test.rb b/Library/Homebrew/test/sandbox_test.rb
index 2a062cb10..a633defce 100644
--- a/Library/Homebrew/test/sandbox_test.rb
+++ b/Library/Homebrew/test/sandbox_test.rb
@@ -3,26 +3,23 @@ require "sandbox"
 
 class SandboxTest < Homebrew::TestCase
   def setup
+    super
     skip "sandbox not implemented" unless Sandbox.available?
     @sandbox = Sandbox.new
     @dir = Pathname.new(mktmpdir)
     @file = @dir/"foo"
   end
 
-  def teardown
-    @dir.rmtree
-  end
-
   def test_formula?
     f = formula { url "foo-1.0" }
     f2 = formula { url "bar-1.0" }
     f2.stubs(:tap).returns(Tap.fetch("test/tap"))
 
-    ARGV.stubs(:sandbox?).returns true
+    ENV["HOMEBREW_SANDBOX"] = "1"
     assert Sandbox.formula?(f),
       "Formulae should be sandboxed if --sandbox was passed."
 
-    ARGV.stubs(:sandbox?).returns false
+    ENV.delete("HOMEBREW_SANDBOX")
     assert Sandbox.formula?(f),
       "Formulae should be sandboxed if in a sandboxed tap."
     refute Sandbox.formula?(f2),
@@ -30,7 +27,7 @@ class SandboxTest < Homebrew::TestCase
   end
 
   def test_test?
-    ARGV.stubs(:no_sandbox?).returns false
+    ENV.delete("HOMEBREW_NO_SANDBOX")
     assert Sandbox.test?,
       "Tests should be sandboxed unless --no-sandbox was passed."
   end
@@ -50,7 +47,7 @@ class SandboxTest < Homebrew::TestCase
 
   def test_complains_on_failure
     Utils.expects(popen_read: "foo")
-    ARGV.stubs(verbose?: true)
+    ENV["HOMEBREW_VERBOSE"] = "1"
     out, _err = capture_io do
       assert_raises(ErrorDuringExecution) { @sandbox.exec "false" }
     end
@@ -64,7 +61,7 @@ class SandboxTest < Homebrew::TestCase
       bar
     EOS
     Utils.expects(popen_read: with_bogus_error)
-    ARGV.stubs(verbose?: true)
+    ENV["HOMEBREW_VERBOSE"] = "1"
     out, _err = capture_io do
       assert_raises(ErrorDuringExecution) { @sandbox.exec "false" }
     end
diff --git a/Library/Homebrew/test/search_remote_tap_test.rb b/Library/Homebrew/test/search_remote_tap_test.rb
deleted file mode 100644
index 9dd9ee654..000000000
--- a/Library/Homebrew/test/search_remote_tap_test.rb
+++ /dev/null
@@ -1,19 +0,0 @@
-require "testing_env"
-require "cmd/search"
-
-class SearchRemoteTapTests < Homebrew::TestCase
-  def test_search_remote_tap
-    json_response = {
-      "tree" => [
-        {
-          "path" => "Formula/not-a-formula.rb",
-          "type" => "blob",
-        },
-      ],
-    }
-
-    GitHub.stubs(:open).yields(json_response)
-
-    assert_equal ["homebrew/not-a-tap/not-a-formula"], Homebrew.search_tap("homebrew", "not-a-tap", "not-a-formula")
-  end
-end
diff --git a/Library/Homebrew/test/search_test.rb b/Library/Homebrew/test/search_test.rb
deleted file mode 100644
index 70b6f01fb..000000000
--- a/Library/Homebrew/test/search_test.rb
+++ /dev/null
@@ -1,30 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestSearch < IntegrationCommandTestCase
-  def test_search
-    setup_test_formula "testball"
-    desc_cache = HOMEBREW_CACHE/"desc_cache.json"
-    refute_predicate desc_cache, :exist?, "Cached file should not exist"
-
-    assert_match "testball", cmd("search")
-    assert_match "testball", cmd("search", "testball")
-    assert_match "testball", cmd("search", "homebrew/homebrew-core/testball")
-    assert_match "testball", cmd("search", "--desc", "Some test")
-
-    flags = {
-      "macports" => "https://www.macports.org/ports.php?by=name&substr=testball",
-      "fink" => "http://pdb.finkproject.org/pdb/browse.php?summary=testball",
-      "debian" => "https://packages.debian.org/search?keywords=testball&searchon=names&suite=all&section=all",
-      "opensuse" => "https://software.opensuse.org/search?q=testball",
-      "fedora" => "https://admin.fedoraproject.org/pkgdb/packages/%2Atestball%2A/",
-      "ubuntu" => "http://packages.ubuntu.com/search?keywords=testball&searchon=names&suite=all&section=all",
-    }
-
-    flags.each do |flag, url|
-      assert_equal url, cmd("search", "--#{flag}",
-        "testball", "HOMEBREW_BROWSER" => "echo")
-    end
-
-    assert_predicate desc_cache, :exist?, "Cached file should exist"
-  end
-end
diff --git a/Library/Homebrew/test/services_test.rb b/Library/Homebrew/test/services_test.rb
deleted file mode 100644
index 280aeb9f4..000000000
--- a/Library/Homebrew/test/services_test.rb
+++ /dev/null
@@ -1,11 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestServices < IntegrationCommandTestCase
-  def test_services
-    needs_test_cmd_taps
-    needs_macos
-    setup_remote_tap("homebrew/services")
-    assert_equal "Warning: No services available to control with `brew services`",
-      cmd("services", "list")
-  end
-end
diff --git a/Library/Homebrew/test/sh_test.rb b/Library/Homebrew/test/sh_test.rb
deleted file mode 100644
index 48fcdc54a..000000000
--- a/Library/Homebrew/test/sh_test.rb
+++ /dev/null
@@ -1,8 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestSh < IntegrationCommandTestCase
-  def test_sh
-    assert_match "Your shell has been configured",
-                 cmd("sh", "SHELL" => which("true"))
-  end
-end
diff --git a/Library/Homebrew/test/shell_test.rb b/Library/Homebrew/test/shell_test.rb
deleted file mode 100644
index 877acb5c8..000000000
--- a/Library/Homebrew/test/shell_test.rb
+++ /dev/null
@@ -1,59 +0,0 @@
-require "testing_env"
-require "utils/shell"
-
-class ShellSmokeTest < Homebrew::TestCase
-  def test_path_to_shell
-    # raw command name
-    assert_equal :bash, Utils::Shell.path_to_shell("bash")
-    # full path
-    assert_equal :bash, Utils::Shell.path_to_shell("/bin/bash")
-    # versions
-    assert_equal :zsh, Utils::Shell.path_to_shell("zsh-5.2")
-    # strip newline too
-    assert_equal :zsh, Utils::Shell.path_to_shell("zsh-5.2\n")
-  end
-
-  def test_path_to_shell_failure
-    assert_equal nil, Utils::Shell.path_to_shell("")
-    assert_equal nil, Utils::Shell.path_to_shell("@@@@@@")
-    assert_equal nil, Utils::Shell.path_to_shell("invalid_shell-4.2")
-  end
-
-  def test_sh_quote
-    assert_equal "''", Utils::Shell.sh_quote("")
-    assert_equal "\\\\", Utils::Shell.sh_quote("\\")
-    assert_equal "'\n'", Utils::Shell.sh_quote("\n")
-    assert_equal "\\$", Utils::Shell.sh_quote("$")
-    assert_equal "word", Utils::Shell.sh_quote("word")
-  end
-
-  def test_csh_quote
-    assert_equal "''", Utils::Shell.csh_quote("")
-    assert_equal "\\\\", Utils::Shell.csh_quote("\\")
-    # note this test is different than for sh
-    assert_equal "'\\\n'", Utils::Shell.csh_quote("\n")
-    assert_equal "\\$", Utils::Shell.csh_quote("$")
-    assert_equal "word", Utils::Shell.csh_quote("word")
-  end
-
-  def prepend_path_shell(shell, path, fragment)
-    original_shell = ENV["SHELL"]
-    ENV["SHELL"] = shell
-
-    prepend_message = Utils::Shell.prepend_path_in_shell_profile(path)
-    assert(
-      prepend_message.start_with?(fragment),
-      "#{shell}: expected #{prepend_message} to match #{fragment}"
-    )
-
-    ENV["SHELL"] = original_shell
-  end
-
-  def test_prepend_path_in_shell_profile
-    prepend_path_shell "/bin/tcsh", "/path", "echo 'setenv PATH /path"
-
-    prepend_path_shell "/bin/bash", "/path", "echo 'export PATH=\"/path"
-
-    prepend_path_shell "/usr/local/bin/fish", "/path", "echo 'set -g fish_user_paths \"/path\" $fish_user_paths' >>"
-  end
-end
diff --git a/Library/Homebrew/test/software_spec_spec.rb b/Library/Homebrew/test/software_spec_spec.rb
new file mode 100644
index 000000000..5fd4f598a
--- /dev/null
+++ b/Library/Homebrew/test/software_spec_spec.rb
@@ -0,0 +1,184 @@
+require "software_spec"
+
+RSpec::Matchers.alias_matcher :have_defined_resource, :be_resource_defined
+RSpec::Matchers.alias_matcher :have_defined_option, :be_option_defined
+
+describe SoftwareSpec do
+  let(:owner) { double(name: "some_name", full_name: "some_name", tap: "homebrew/core") }
+
+  describe "#resource" do
+    it "defines a resource" do
+      subject.resource("foo") { url "foo-1.0" }
+      expect(subject).to have_defined_resource("foo")
+    end
+
+    it "sets itself to be the resource's owner" do
+      subject.resource("foo") { url "foo-1.0" }
+      subject.owner = owner
+      subject.resources.each_value do |r|
+        expect(r.owner).to eq(subject)
+      end
+    end
+
+    it "receives the owner's version if it has no own version" do
+      subject.url("foo-42")
+      subject.resource("bar") { url "bar" }
+      subject.owner = owner
+
+      expect(subject.resource("bar").version).to eq("42")
+    end
+
+    it "raises an error when duplicate resources are defined" do
+      subject.resource("foo") { url "foo-1.0" }
+      expect {
+        subject.resource("foo") { url "foo-1.0" }
+      }.to raise_error(DuplicateResourceError)
+    end
+
+    it "raises an error when accessing missing resources" do
+      subject.owner = owner
+      expect {
+        subject.resource("foo")
+      }.to raise_error(ResourceMissingError)
+    end
+  end
+
+  describe "#owner" do
+    it "sets the owner" do
+      subject.owner = owner
+      expect(subject.owner).to eq(owner)
+    end
+
+    it "sets the name" do
+      subject.owner = owner
+      expect(subject.name).to eq(owner.name)
+    end
+  end
+
+  describe "#option" do
+    it "defines an option" do
+      subject.option("foo")
+      expect(subject).to have_defined_option("foo")
+    end
+
+    it "raises an error when it begins with dashes" do
+      expect {
+        subject.option("--foo")
+      }.to raise_error(ArgumentError)
+    end
+
+    it "raises an error when name is empty" do
+      expect {
+        subject.option("")
+      }.to raise_error(ArgumentError)
+    end
+
+    it "special cases the cxx11 option" do
+      subject.option(:cxx11)
+      expect(subject).to have_defined_option("c++11")
+      expect(subject).not_to have_defined_option("cxx11")
+    end
+
+    it "supports options with descriptions" do
+      subject.option("bar", "description")
+      expect(subject.options.first.description).to eq("description")
+    end
+
+    it "defaults to an empty string when no description is given" do
+      subject.option("foo")
+      expect(subject.options.first.description).to eq("")
+    end
+  end
+
+  describe "#deprecated_option" do
+    it "allows specifying deprecated options" do
+      subject.deprecated_option("foo" => "bar")
+      expect(subject.deprecated_options).not_to be_empty
+      expect(subject.deprecated_options.first.old).to eq("foo")
+      expect(subject.deprecated_options.first.current).to eq("bar")
+    end
+
+    it "allows specifying deprecated options as a Hash from an Array/String to an Array/String" do
+      subject.deprecated_option(["foo1", "foo2"] => "bar1", "foo3" => ["bar2", "bar3"])
+      expect(subject.deprecated_options).to include(DeprecatedOption.new("foo1", "bar1"))
+      expect(subject.deprecated_options).to include(DeprecatedOption.new("foo2", "bar1"))
+      expect(subject.deprecated_options).to include(DeprecatedOption.new("foo3", "bar2"))
+      expect(subject.deprecated_options).to include(DeprecatedOption.new("foo3", "bar3"))
+    end
+
+    it "raises an error when empty" do
+      expect {
+        subject.deprecated_option({})
+      }.to raise_error(ArgumentError)
+    end
+  end
+
+  describe "#depends_on" do
+    it "allows specifying dependencies" do
+      subject.depends_on("foo")
+      expect(subject.deps.first.name).to eq("foo")
+    end
+
+    it "allows specifying optional dependencies" do
+      subject.depends_on "foo" => :optional
+      expect(subject).to have_defined_option("with-foo")
+    end
+
+    it "allows specifying recommended dependencies" do
+      subject.depends_on "bar" => :recommended
+      expect(subject).to have_defined_option("without-bar")
+    end
+  end
+
+  specify "explicit options override defaupt depends_on option description" do
+    subject.option("with-foo", "blah")
+    subject.depends_on("foo" => :optional)
+    expect(subject.options.first.description).to eq("blah")
+  end
+
+  describe "#patch" do
+    it "adds a patch" do
+      subject.patch(:p1, :DATA)
+      expect(subject.patches.count).to eq(1)
+      expect(subject.patches.first.strip).to eq(:p1)
+    end
+  end
+end
+
+describe HeadSoftwareSpec do
+  specify "#version" do
+    expect(subject.version).to eq(Version.create("HEAD"))
+  end
+
+  specify "#verify_download_integrity" do
+    expect(subject.verify_download_integrity(Object.new)).to be nil
+  end
+end
+
+describe BottleSpecification do
+  specify "#sha256" do
+    checksums = {
+      snow_leopard_32: "deadbeef" * 8,
+      snow_leopard: "faceb00c" * 8,
+      lion: "baadf00d" * 8,
+      mountain_lion: "8badf00d" * 8,
+    }
+
+    checksums.each_pair do |cat, digest|
+      subject.sha256(digest => cat)
+    end
+
+    checksums.each_pair do |cat, digest|
+      checksum, = subject.checksum_for(cat)
+      expect(Checksum.new(:sha256, digest)).to eq(checksum)
+    end
+  end
+
+  %w[root_url prefix cellar rebuild].each do |method|
+    specify "##{method}" do
+      object = Object.new
+      subject.public_send(method, object)
+      expect(subject.public_send(method)).to eq(object)
+    end
+  end
+end
diff --git a/Library/Homebrew/test/software_spec_test.rb b/Library/Homebrew/test/software_spec_test.rb
deleted file mode 100644
index d9226f8c3..000000000
--- a/Library/Homebrew/test/software_spec_test.rb
+++ /dev/null
@@ -1,181 +0,0 @@
-require "testing_env"
-require "software_spec"
-
-class SoftwareSpecTests < Homebrew::TestCase
-  def setup
-    @spec = SoftwareSpec.new
-  end
-
-  def test_resource
-    @spec.resource("foo") { url "foo-1.0" }
-    assert @spec.resource_defined?("foo")
-  end
-
-  def test_raises_when_duplicate_resources_are_defined
-    @spec.resource("foo") { url "foo-1.0" }
-    assert_raises(DuplicateResourceError) do
-      @spec.resource("foo") { url "foo-1.0" }
-    end
-  end
-
-  def test_raises_when_accessing_missing_resources
-    @spec.owner = Class.new do
-      def name
-        "test"
-      end
-
-      def full_name
-        "test"
-      end
-
-      def tap
-        "homebrew/core"
-      end
-    end.new
-    assert_raises(ResourceMissingError) { @spec.resource("foo") }
-  end
-
-  def test_set_owner
-    owner = stub name: "some_name",
-                 full_name: "some_name",
-                 tap: "homebrew/core"
-    @spec.owner = owner
-    assert_equal owner, @spec.owner
-  end
-
-  def test_resource_owner
-    @spec.resource("foo") { url "foo-1.0" }
-    @spec.owner = stub name: "some_name",
-                       full_name: "some_name",
-                       tap: "homebrew/core"
-    assert_equal "some_name", @spec.name
-    @spec.resources.each_value { |r| assert_equal @spec, r.owner }
-  end
-
-  def test_resource_without_version_receives_owners_version
-    @spec.url("foo-42")
-    @spec.resource("bar") { url "bar" }
-    @spec.owner = stub name: "some_name",
-                       full_name: "some_name",
-                       tap: "homebrew/core"
-    assert_version_equal "42", @spec.resource("bar").version
-  end
-
-  def test_option
-    @spec.option("foo")
-    assert @spec.option_defined?("foo")
-  end
-
-  def test_option_raises_when_begins_with_dashes
-    assert_raises(ArgumentError) { @spec.option("--foo") }
-  end
-
-  def test_option_raises_when_name_empty
-    assert_raises(ArgumentError) { @spec.option("") }
-  end
-
-  def test_cxx11_option_special_case
-    @spec.option(:cxx11)
-    assert @spec.option_defined?("c++11")
-    refute @spec.option_defined?("cxx11")
-  end
-
-  def test_option_description
-    @spec.option("bar", "description")
-    assert_equal "description", @spec.options.first.description
-  end
-
-  def test_option_description_defaults_to_empty_string
-    @spec.option("foo")
-    assert_equal "", @spec.options.first.description
-  end
-
-  def test_deprecated_option
-    @spec.deprecated_option("foo" => "bar")
-    refute_empty @spec.deprecated_options
-    assert_equal "foo", @spec.deprecated_options.first.old
-    assert_equal "bar", @spec.deprecated_options.first.current
-  end
-
-  def test_deprecated_options
-    @spec.deprecated_option(["foo1", "foo2"] => "bar1", "foo3" => ["bar2", "bar3"])
-    assert_includes @spec.deprecated_options, DeprecatedOption.new("foo1", "bar1")
-    assert_includes @spec.deprecated_options, DeprecatedOption.new("foo2", "bar1")
-    assert_includes @spec.deprecated_options, DeprecatedOption.new("foo3", "bar2")
-    assert_includes @spec.deprecated_options, DeprecatedOption.new("foo3", "bar3")
-  end
-
-  def test_deprecated_option_raises_when_empty
-    assert_raises(ArgumentError) { @spec.deprecated_option({}) }
-  end
-
-  def test_depends_on
-    @spec.depends_on("foo")
-    assert_equal "foo", @spec.deps.first.name
-  end
-
-  def test_dependency_option_integration
-    @spec.depends_on "foo" => :optional
-    @spec.depends_on "bar" => :recommended
-    assert @spec.option_defined?("with-foo")
-    assert @spec.option_defined?("without-bar")
-  end
-
-  def test_explicit_options_override_default_dep_option_description
-    @spec.option("with-foo", "blah")
-    @spec.depends_on("foo" => :optional)
-    assert_equal "blah", @spec.options.first.description
-  end
-
-  def test_patch
-    @spec.patch :p1, :DATA
-    assert_equal 1, @spec.patches.length
-    assert_equal :p1, @spec.patches.first.strip
-  end
-end
-
-class HeadSoftwareSpecTests < Homebrew::TestCase
-  def setup
-    @spec = HeadSoftwareSpec.new
-  end
-
-  def test_version
-    assert_version_equal "HEAD", @spec.version
-  end
-
-  def test_verify_download_integrity
-    assert_nil @spec.verify_download_integrity(Object.new)
-  end
-end
-
-class BottleSpecificationTests < Homebrew::TestCase
-  def setup
-    @spec = BottleSpecification.new
-  end
-
-  def test_checksum_setters
-    checksums = {
-      snow_leopard_32: "deadbeef"*8,
-      snow_leopard: "faceb00c"*8,
-      lion: "baadf00d"*8,
-      mountain_lion: "8badf00d"*8,
-    }
-
-    checksums.each_pair do |cat, digest|
-      @spec.sha256(digest => cat)
-    end
-
-    checksums.each_pair do |cat, digest|
-      checksum, = @spec.checksum_for(cat)
-      assert_equal Checksum.new(:sha256, digest), checksum
-    end
-  end
-
-  def test_other_setters
-    double = Object.new
-    %w[root_url prefix cellar rebuild].each do |method|
-      @spec.send(method, double)
-      assert_equal double, @spec.send(method)
-    end
-  end
-end
diff --git a/Library/Homebrew/test/spec_helper.rb b/Library/Homebrew/test/spec_helper.rb
new file mode 100644
index 000000000..9a4dbe026
--- /dev/null
+++ b/Library/Homebrew/test/spec_helper.rb
@@ -0,0 +1,101 @@
+require "find"
+require "pathname"
+require "rspec/its"
+require "rspec/wait"
+require "set"
+
+if ENV["HOMEBREW_TESTS_COVERAGE"]
+  require "simplecov"
+end
+
+$LOAD_PATH.unshift(File.expand_path("#{ENV["HOMEBREW_LIBRARY"]}/Homebrew"))
+$LOAD_PATH.unshift(File.expand_path("#{ENV["HOMEBREW_LIBRARY"]}/Homebrew/test/support/lib"))
+
+require "global"
+require "tap"
+
+require "test/support/helper/shutup"
+require "test/support/helper/fixtures"
+require "test/support/helper/formula"
+require "test/support/helper/spec/shared_context/integration_test"
+
+TEST_DIRECTORIES = [
+  CoreTap.instance.path/"Formula",
+  HOMEBREW_CACHE,
+  HOMEBREW_CACHE_FORMULA,
+  HOMEBREW_CELLAR,
+  HOMEBREW_LOCK_DIR,
+  HOMEBREW_LOGS,
+  HOMEBREW_TEMP,
+].freeze
+
+RSpec.configure do |config|
+  config.order = :random
+  config.include(Test::Helper::Shutup)
+  config.include(Test::Helper::Fixtures)
+  config.include(Test::Helper::Formula)
+  config.before(:each) do |example|
+    if example.metadata[:needs_macos]
+      skip "Not on macOS." unless OS.mac?
+    end
+
+    if example.metadata[:needs_official_cmd_taps]
+      skip "Needs official command Taps." unless ENV["HOMEBREW_TEST_OFFICIAL_CMD_TAPS"]
+    end
+
+    if example.metadata[:needs_python]
+      skip "Python not installed." unless which("python")
+    end
+  end
+  config.around(:each) do |example|
+    begin
+      TEST_DIRECTORIES.each(&:mkpath)
+
+      @__homebrew_failed = Homebrew.failed?
+
+      @__files_before_test = Find.find(TEST_TMPDIR).map { |f| f.sub(TEST_TMPDIR, "") }
+
+      @__argv = ARGV.dup
+      @__env = ENV.to_hash # dup doesn't work on ENV
+
+      example.run
+    ensure
+      ARGV.replace(@__argv)
+      ENV.replace(@__env)
+
+      Tab.clear_cache
+
+      FileUtils.rm_rf [
+        TEST_DIRECTORIES.map(&:children),
+        HOMEBREW_LINKED_KEGS,
+        HOMEBREW_PINNED_KEGS,
+        HOMEBREW_PREFIX/".git",
+        HOMEBREW_PREFIX/"bin",
+        HOMEBREW_PREFIX/"share",
+        HOMEBREW_PREFIX/"opt",
+        HOMEBREW_PREFIX/"Caskroom",
+        HOMEBREW_LIBRARY/"Taps/caskroom",
+        HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-bundle",
+        HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-foo",
+        HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-services",
+        HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-shallow",
+        HOMEBREW_REPOSITORY/".git",
+        CoreTap.instance.path/".git",
+        CoreTap.instance.alias_dir,
+        CoreTap.instance.path/"formula_renames.json",
+      ]
+
+      files_after_test = Find.find(TEST_TMPDIR).map { |f| f.sub(TEST_TMPDIR, "") }
+
+      diff = Set.new(@__files_before_test) ^ Set.new(files_after_test)
+      expect(diff).to be_empty, <<-EOS.undent
+        file leak detected:
+        #{diff.map { |f| "  #{f}" }.join("\n")}
+      EOS
+
+      Homebrew.failed = @__homebrew_failed
+    end
+  end
+end
+
+RSpec::Matchers.alias_matcher :have_failed, :be_failed
diff --git a/Library/Homebrew/test/stdlib_test.rb b/Library/Homebrew/test/stdlib_test.rb
deleted file mode 100644
index 3babfd58a..000000000
--- a/Library/Homebrew/test/stdlib_test.rb
+++ /dev/null
@@ -1,62 +0,0 @@
-require "testing_env"
-require "formula"
-require "cxxstdlib"
-
-class CxxStdlibTests < Homebrew::TestCase
-  def setup
-    @clang = CxxStdlib.create(:libstdcxx, :clang)
-    @gcc   = CxxStdlib.create(:libstdcxx, :gcc)
-    @gcc40 = CxxStdlib.create(:libstdcxx, :gcc_4_0)
-    @gcc42 = CxxStdlib.create(:libstdcxx, :gcc_4_2)
-    @gcc48 = CxxStdlib.create(:libstdcxx, "gcc-4.8")
-    @gcc49 = CxxStdlib.create(:libstdcxx, "gcc-4.9")
-    @lcxx  = CxxStdlib.create(:libcxx, :clang)
-    @purec = CxxStdlib.create(nil, :clang)
-  end
-
-  def test_apple_libstdcxx_intercompatibility
-    assert @clang.compatible_with?(@gcc)
-    assert @clang.compatible_with?(@gcc42)
-  end
-
-  def test_compatibility_same_compilers_and_type
-    assert @gcc.compatible_with?(@gcc)
-    assert @gcc48.compatible_with?(@gcc48)
-    assert @clang.compatible_with?(@clang)
-  end
-
-  def test_apple_gnu_libstdcxx_incompatibility
-    assert !@clang.compatible_with?(@gcc48)
-    assert !@gcc48.compatible_with?(@clang)
-  end
-
-  def test_gnu_cross_version_incompatibility
-    assert !@gcc48.compatible_with?(@gcc49)
-    assert !@gcc49.compatible_with?(@gcc48)
-  end
-
-  def test_libstdcxx_libcxx_incompatibility
-    assert !@clang.compatible_with?(@lcxx)
-    assert !@lcxx.compatible_with?(@clang)
-  end
-
-  def test_apple_compiler_reporting
-    assert_predicate @clang, :apple_compiler?
-    assert_predicate @gcc, :apple_compiler?
-    assert_predicate @gcc42, :apple_compiler?
-    refute_predicate @gcc48, :apple_compiler?
-  end
-
-  def test_type_string_formatting
-    assert_equal "libstdc++", @clang.type_string
-    assert_equal "libc++", @lcxx.type_string
-  end
-
-  def test_compatibility_for_non_cxx_software
-    assert @purec.compatible_with?(@clang)
-    assert @clang.compatible_with?(@purec)
-    assert @purec.compatible_with?(@purec)
-    assert @purec.compatible_with?(@gcc48)
-    assert @gcc48.compatible_with?(@purec)
-  end
-end
diff --git a/Library/Homebrew/test/string_spec.rb b/Library/Homebrew/test/string_spec.rb
new file mode 100644
index 000000000..d1b820b66
--- /dev/null
+++ b/Library/Homebrew/test/string_spec.rb
@@ -0,0 +1,49 @@
+require "extend/string"
+
+describe String do
+  describe "#undent" do
+    it "removes leading whitespace, taking the first line as reference" do
+      string = <<-EOS.undent
+        hi
+........my friend over
+          there
+      EOS
+
+      expect(string).to eq("hi\n........my friend over\n  there\n")
+    end
+
+    it "removes nothing if the text is not indented" do
+      string = <<-EOS.undent
+hi
+I'm not indented
+      EOS
+
+      expect(string).to eq("hi\nI'm not indented\n")
+    end
+
+    it "can be nested" do
+      nested_string = <<-EOS.undent
+        goodbye
+      EOS
+
+      string = <<-EOS.undent
+        hello
+        #{nested_string}
+      EOS
+
+      expect(string).to eq("hello\ngoodbye\n\n")
+    end
+  end
+end
+
+describe StringInreplaceExtension do
+  subject { string.extend(described_class) }
+  let(:string) { "foobar" }
+
+  describe "#sub!" do
+    it "adds an error to #errors when no replacement was made" do
+      subject.sub! "not here", "test"
+      expect(subject.errors).to eq(['expected replacement of "not here" with "test"'])
+    end
+  end
+end
diff --git a/Library/Homebrew/test/string_test.rb b/Library/Homebrew/test/string_test.rb
deleted file mode 100644
index 497c4badb..000000000
--- a/Library/Homebrew/test/string_test.rb
+++ /dev/null
@@ -1,40 +0,0 @@
-require "testing_env"
-require "extend/string"
-
-class StringTest < Homebrew::TestCase
-  def test_undent
-    undented = <<-EOS.undent
-    hi
-....my friend over
-    there
-    EOS
-    assert_equal "hi\n....my friend over\nthere\n", undented
-  end
-
-  def test_undent_not_indented
-    undented = <<-EOS.undent
-hi
-I'm not indented
-    EOS
-    assert_equal "hi\nI'm not indented\n", undented
-  end
-
-  def test_undent_nested
-    nest = <<-EOS.undent
-      goodbye
-    EOS
-
-    undented = <<-EOS.undent
-      hello
-      #{nest}
-    EOS
-
-    assert_equal "hello\ngoodbye\n\n", undented
-  end
-
-  def test_inreplace_sub_failure
-    s = "foobar".extend StringInreplaceExtension
-    s.sub! "not here", "test"
-    assert_equal ['expected replacement of "not here" with "test"'], s.errors
-  end
-end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/appcast-checkpoint-sha256-for-empty-string.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/appcast-checkpoint-sha256-for-empty-string.rb
new file mode 100644
index 000000000..4e74d728d
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/appcast-checkpoint-sha256-for-empty-string.rb
@@ -0,0 +1,4 @@
+cask 'appcast-checkpoint-sha256-for-empty-string' do
+  appcast 'http://localhost/appcast.xml',
+          checkpoint: 'e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/appcast-invalid-checkpoint.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/appcast-invalid-checkpoint.rb
new file mode 100644
index 000000000..8b6934148
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/appcast-invalid-checkpoint.rb
@@ -0,0 +1,4 @@
+cask 'appcast-invalid-checkpoint' do
+  appcast 'http://localhost/appcast.xml',
+          checkpoint: 'not a valid shasum'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/appcast-missing-checkpoint.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/appcast-missing-checkpoint.rb
new file mode 100644
index 000000000..fefdbcb3a
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/appcast-missing-checkpoint.rb
@@ -0,0 +1,3 @@
+cask 'appcast-missing-checkpoint' do
+  appcast 'http://localhost/appcast.xml'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/appcast-valid-checkpoint.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/appcast-valid-checkpoint.rb
new file mode 100644
index 000000000..84c9ca512
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/appcast-valid-checkpoint.rb
@@ -0,0 +1,4 @@
+cask 'appcast-valid-checkpoint' do
+  appcast 'http://localhost/appcast.xml',
+          checkpoint: 'd5b2dfbef7ea28c25f7a77cd7fa14d013d82b626db1d82e00e25822464ba19e2'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/appdir-interpolation.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/appdir-interpolation.rb
new file mode 100644
index 000000000..e4b3e79e6
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/appdir-interpolation.rb
@@ -0,0 +1,9 @@
+cask 'appdir-interpolation' do
+  version '2.61'
+  sha256 'e44ffa103fbf83f55c8d0b1bea309a43b2880798dae8620b1ee8da5e1095ec68'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/transmission-2.61.dmg"
+  homepage 'http://example.com/appdir-interpolation'
+
+  binary "#{appdir}/some/path"
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/auto-updates.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/auto-updates.rb
new file mode 100644
index 000000000..1cada2561
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/auto-updates.rb
@@ -0,0 +1,11 @@
+cask 'auto-updates' do
+  version '2.61'
+  sha256 'e44ffa103fbf83f55c8d0b1bea309a43b2880798dae8620b1ee8da5e1095ec68'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/transmission-2.61.dmg"
+  homepage 'http://example.com/auto-updates'
+
+  auto_updates true
+
+  app 'Transmission.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/bad-checksum.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/bad-checksum.rb
new file mode 100644
index 000000000..254ee59fd
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/bad-checksum.rb
@@ -0,0 +1,9 @@
+cask 'bad-checksum' do
+  version '1.2.3'
+  sha256 'badbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadb'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/basic-cask.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/basic-cask.rb
new file mode 100644
index 000000000..ff1d90003
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/basic-cask.rb
@@ -0,0 +1,9 @@
+cask 'basic-cask' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url 'http://example.com/TestCask.dmg'
+  homepage 'http://example.com/'
+
+  app 'TestCask.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/booby-trap.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/booby-trap.rb
new file mode 100644
index 000000000..21bd97952
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/booby-trap.rb
@@ -0,0 +1,8 @@
+cask 'booby-trap' do
+  version '0.0.7'
+
+  url do
+    # to be lazily evaluated
+    fail 'Boom'
+  end
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/container-7z.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/container-7z.rb
new file mode 100644
index 000000000..5b043a75e
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/container-7z.rb
@@ -0,0 +1,11 @@
+cask 'container-7z' do
+  version '1.2.3'
+  sha256 '3f9542ace85ed5f88549e2d0ea82210f8ddc87e0defbb78469d3aed719b3c964'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/container.7z"
+  homepage 'https://example.com/container-7z'
+
+  depends_on formula: 'unar'
+
+  app 'container'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/container-air.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/container-air.rb
new file mode 100644
index 000000000..5aaf3d53e
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/container-air.rb
@@ -0,0 +1,9 @@
+cask 'container-air' do
+  version '0.1'
+  sha256 '554472e163f8a028629b12b468e29acda9f16b223dff74fcd218bba73cc2365a'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/container.air"
+  homepage 'https://example.com/container-air'
+
+  app 'container.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/container-bzip2.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/container-bzip2.rb
new file mode 100644
index 000000000..60f834b7f
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/container-bzip2.rb
@@ -0,0 +1,9 @@
+cask 'container-bzip2' do
+  version '1.2.3'
+  sha256 'eaf67b3a62cb9275f96e45d05c70b94bef9ef1dae344083e93eda6b0b388a61c'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/container.bz2"
+  homepage 'https://example.com/container-bzip2'
+
+  app 'container-bzip2--1.2.3'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/container-cab.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/container-cab.rb
new file mode 100644
index 000000000..e57131567
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/container-cab.rb
@@ -0,0 +1,11 @@
+cask 'container-cab' do
+  version '1.2.3'
+  sha256 'c267f5cebb14814c8e612a8b7d2bda02aec913f869509b6f1d3883427c0f552b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/container.cab"
+  homepage 'https://example.com/container-cab'
+
+  depends_on formula: 'cabextract'
+
+  app 'container'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/container-dmg.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/container-dmg.rb
new file mode 100644
index 000000000..e9974b5d2
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/container-dmg.rb
@@ -0,0 +1,9 @@
+cask 'container-dmg' do
+  version '1.2.3'
+  sha256 '74d89d4fa5cef175cf43666ce11fefa3741aa1522114042ac75e656be37141a1'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/container.dmg"
+  homepage 'https://example.com/container-dmg'
+
+  app 'container'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/container-gzip.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/container-gzip.rb
new file mode 100644
index 000000000..0bfc4108f
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/container-gzip.rb
@@ -0,0 +1,9 @@
+cask 'container-gzip' do
+  version '1.2.3'
+  sha256 'fa4ebb5246583c4b6e62e1df4e3b71b4e38a1d7d91c025665827195d36214b20'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/container.gz"
+  homepage 'https://example.com/container-gzip'
+
+  app 'container'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/container-lzma.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/container-lzma.rb
new file mode 100644
index 000000000..92d2c253e
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/container-lzma.rb
@@ -0,0 +1,11 @@
+cask 'container-lzma' do
+  version '1.2.3'
+  sha256 '9d7edb32d02ab9bd9749a5bde8756595ea4cfcb1da02ca11c30fb591d4c1ed85'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/container.lzma"
+  homepage 'https://example.com/container-lzma'
+
+  depends_on formula: 'lzma'
+
+  app 'container-lzma--1.2.3'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/container-pkg.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/container-pkg.rb
new file mode 100644
index 000000000..2ff4cca1e
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/container-pkg.rb
@@ -0,0 +1,7 @@
+cask 'container-pkg' do
+  version '1.2.3'
+  sha256 '611c50c8a2a2098951d2cd0fd54787ed81b92cd97b4b08bd7cba17f1e1d8e40b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/container.pkg"
+  homepage 'https://example.com/container-pkg'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/container-rar.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/container-rar.rb
new file mode 100644
index 000000000..33ea670d1
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/container-rar.rb
@@ -0,0 +1,11 @@
+cask 'container-rar' do
+  version '1.2.3'
+  sha256 '419af7864c0e1f125515c49b08bd22e0f7de39f5285897c440fe03c714871763'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/container.rar"
+  homepage 'https://example.com/container-rar'
+
+  depends_on formula: 'unar'
+
+  app 'container'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/container-sit.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/container-sit.rb
new file mode 100644
index 000000000..5715795a7
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/container-sit.rb
@@ -0,0 +1,11 @@
+cask 'container-sit' do
+  version '1.2.3'
+  sha256 '0d21a64dce625044345c8ecca888e5439feaf254dac7f884917028a744f93cf3'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/container.sit"
+  homepage 'https://example.com/container-sit'
+
+  depends_on formula: 'unar'
+
+  app 'container'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/container-tar-gz.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/container-tar-gz.rb
new file mode 100644
index 000000000..e32931c89
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/container-tar-gz.rb
@@ -0,0 +1,9 @@
+cask 'container-tar-gz' do
+  version '1.2.3'
+  sha256 'fab685fabf73d5a9382581ce8698fce9408f5feaa49fa10d9bc6c510493300f5'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/container.tar.gz"
+  homepage 'https://example.com/container-tar-gz'
+
+  app 'container'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/container-xar.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/container-xar.rb
new file mode 100644
index 000000000..82a751d5d
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/container-xar.rb
@@ -0,0 +1,9 @@
+cask 'container-xar' do
+  version '1.2.3'
+  sha256 '5bb8e09a6fc630ebeaf266b1fd2d15e2ae7d32d7e4da6668a8093426fa1ba509'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/container.xar"
+  homepage 'https://example.com/container-xar'
+
+  app 'container'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/container-xz.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/container-xz.rb
new file mode 100644
index 000000000..3f844af04
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/container-xz.rb
@@ -0,0 +1,11 @@
+cask 'container-xz' do
+  version '1.2.3'
+  sha256 '839263f474edde1d54a9101606e6f0dc9d963acc93f6dcc5af8d10ebc3187c02'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/container.xz"
+  homepage 'https://example.com/container-xz'
+
+  depends_on formula: 'xz'
+
+  app 'container-xz--1.2.3'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/generic-artifact-absolute-target.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/generic-artifact-absolute-target.rb
new file mode 100644
index 000000000..a1844a9c9
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/generic-artifact-absolute-target.rb
@@ -0,0 +1,3 @@
+cask 'generic-artifact-absolute-target' do
+  artifact 'Caffeine.app', target: "#{Hbc.appdir}/Caffeine.app"
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/generic-artifact-no-target.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/generic-artifact-no-target.rb
new file mode 100644
index 000000000..a3e65caab
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/generic-artifact-no-target.rb
@@ -0,0 +1,3 @@
+cask 'generic-artifact-no-target' do
+  artifact 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/generic-artifact-relative-target.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/generic-artifact-relative-target.rb
new file mode 100644
index 000000000..eb521e35a
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/generic-artifact-relative-target.rb
@@ -0,0 +1,3 @@
+cask 'generic-artifact-relative-target' do
+  artifact 'Caffeine.app', target: 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid-sha256.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid-sha256.rb
new file mode 100644
index 000000000..2804da7c3
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid-sha256.rb
@@ -0,0 +1,4 @@
+cask 'invalid-sha256' do
+  version '1.2.3'
+  sha256 'not a valid shasum'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-appcast-multiple.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-appcast-multiple.rb
new file mode 100644
index 000000000..37634f619
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-appcast-multiple.rb
@@ -0,0 +1,13 @@
+cask 'invalid-appcast-multiple' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  appcast 'http://example.com/appcast1.xml',
+          checkpoint: '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+  appcast 'http://example.com/appcast2.xml',
+          checkpoint: '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+  homepage 'http://example.com/invalid-appcast-multiple'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-appcast-url.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-appcast-url.rb
new file mode 100644
index 000000000..7b51ffb53
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-appcast-url.rb
@@ -0,0 +1,11 @@
+cask 'invalid-appcast-url' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  appcast 1,
+          checkpoint: '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+  homepage 'http://example.com/invalid-appcast-url'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-conflicts-with-key.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-conflicts-with-key.rb
new file mode 100644
index 000000000..b066139ce
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-conflicts-with-key.rb
@@ -0,0 +1,11 @@
+cask 'invalid-conflicts-with-key' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/invalid-conflicts-with-key'
+
+  conflicts_with no_such_key: 'unar'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-arch-value.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-arch-value.rb
new file mode 100644
index 000000000..b21912a6e
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-arch-value.rb
@@ -0,0 +1,11 @@
+cask 'invalid-depends-on-arch-value' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/invalid-depends-on-arch-value'
+
+  depends_on arch: :no_such_arch
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-key.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-key.rb
new file mode 100644
index 000000000..24a912893
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-key.rb
@@ -0,0 +1,11 @@
+cask 'invalid-depends-on-key' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/invalid-depends-on-key'
+
+  depends_on no_such_key: 'unar'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-macos-bad-release.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-macos-bad-release.rb
new file mode 100644
index 000000000..723ceacbb
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-macos-bad-release.rb
@@ -0,0 +1,11 @@
+cask 'invalid-depends-on-macos-bad-release' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/invalid-depends-on-macos-bad-release'
+
+  depends_on macos: :no_such_release
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-macos-conflicting-forms.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-macos-conflicting-forms.rb
new file mode 100644
index 000000000..689e24b67
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-macos-conflicting-forms.rb
@@ -0,0 +1,12 @@
+cask 'invalid-depends-on-macos-conflicting-forms' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/invalid-depends-on-macos-conflicting-forms'
+
+  depends_on macos: :yosemite
+  depends_on macos: '>= :mavericks'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-x11-value.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-x11-value.rb
new file mode 100644
index 000000000..5c3faec35
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-depends-on-x11-value.rb
@@ -0,0 +1,11 @@
+cask 'invalid-depends-on-x11-value' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/invalid-depends-on-x11-value'
+
+  depends_on x11: :no_such_value
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-conflicting-keys.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-conflicting-keys.rb
new file mode 100644
index 000000000..baf124b7a
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-conflicting-keys.rb
@@ -0,0 +1,12 @@
+cask 'invalid-gpg-conflicting-keys' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/invalid-gpg-conflicting-keys'
+  gpg 'http://example.com/gpg-signature.asc',
+      key_id:  '01234567',
+      key_url: 'http://example.com/gpg-key-url'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-key-id.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-key-id.rb
new file mode 100644
index 000000000..386593b06
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-key-id.rb
@@ -0,0 +1,11 @@
+cask 'invalid-gpg-key-id' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/invalid-gpg-key-id'
+  gpg 'http://example.com/gpg-signature.asc',
+      key_id: '012'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-key-url.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-key-url.rb
new file mode 100644
index 000000000..4108380d2
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-key-url.rb
@@ -0,0 +1,11 @@
+cask 'invalid-gpg-key-url' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/invalid-gpg-key-url'
+  gpg 'http://example.com/gpg-signature.asc',
+      key_url: 1
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-missing-key.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-missing-key.rb
new file mode 100644
index 000000000..3375801c9
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-missing-key.rb
@@ -0,0 +1,10 @@
+cask 'invalid-gpg-missing-key' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/invalid-gpg-missing-keys'
+  gpg 'http://example.com/gpg-signature.asc'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-multiple-stanzas.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-multiple-stanzas.rb
new file mode 100644
index 000000000..b420f74d5
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-multiple-stanzas.rb
@@ -0,0 +1,13 @@
+cask 'invalid-gpg-multiple-stanzas' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/invalid-gpg-multiple-stanzas'
+  gpg 'http://example.com/gpg-signature.asc',
+      key_id: '01234567'
+  gpg 'http://example.com/gpg-signature.asc',
+      key_id: '01234567'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-parameter.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-parameter.rb
new file mode 100644
index 000000000..40f6a9dae
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-parameter.rb
@@ -0,0 +1,11 @@
+cask 'invalid-gpg-parameter' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/invalid-gpg-type'
+  gpg 'http://example.com/gpg-signature.asc',
+      no_such_parameter: :value
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-signature-url.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-signature-url.rb
new file mode 100644
index 000000000..43cc27b08
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-signature-url.rb
@@ -0,0 +1,11 @@
+cask 'invalid-gpg-signature-url' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/invalid-gpg-signature-url'
+  gpg 1,
+      key_id: '01234567'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-type.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-type.rb
new file mode 100644
index 000000000..a369ef875
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-gpg-type.rb
@@ -0,0 +1,11 @@
+cask 'invalid-gpg-type' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/invalid-gpg-type'
+  gpg 'http://example.com/gpg-signature.asc',
+      no_such_parameter: :value
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-header-format.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-header-format.rb
new file mode 100644
index 000000000..c8c613767
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-header-format.rb
@@ -0,0 +1,9 @@
+cask => 'invalid-header-format' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-header-token-mismatch.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-header-token-mismatch.rb
new file mode 100644
index 000000000..af15a13ef
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-header-token-mismatch.rb
@@ -0,0 +1,9 @@
+cask 'invalid-header-token-mismatch-this-text-does-not-belong' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-header-version.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-header-version.rb
new file mode 100644
index 000000000..7e37e61df
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-header-version.rb
@@ -0,0 +1,9 @@
+cask 'invalid-header-version' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-stage-only-conflict.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-stage-only-conflict.rb
new file mode 100644
index 000000000..5a0ccadf6
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-stage-only-conflict.rb
@@ -0,0 +1,10 @@
+cask 'invalid-stage-only-conflict' do
+  version '2.61'
+  sha256 'e44ffa103fbf83f55c8d0b1bea309a43b2880798dae8620b1ee8da5e1095ec68'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/transmission-2.61.dmg"
+  homepage 'http://example.com/invalid-stage-only-conflict'
+
+  app 'Transmission.app'
+  stage_only true
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-two-homepage.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-two-homepage.rb
new file mode 100644
index 000000000..5170a9c0f
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-two-homepage.rb
@@ -0,0 +1,10 @@
+cask 'invalid-two-homepage' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/local-caffeine'
+  homepage 'http://www.example.com/local-caffeine'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-two-url.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-two-url.rb
new file mode 100644
index 000000000..f548400a4
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-two-url.rb
@@ -0,0 +1,10 @@
+cask 'invalid-two-url' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  url 'http://example.com/caffeine.zip'
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-two-version.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-two-version.rb
new file mode 100644
index 000000000..fbffa8a1e
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/invalid/invalid-two-version.rb
@@ -0,0 +1,10 @@
+cask 'invalid-two-version' do
+  version '1.2.3'
+  version '2.0'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/local-caffeine.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/local-caffeine.rb
new file mode 100644
index 000000000..934d22463
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/local-caffeine.rb
@@ -0,0 +1,9 @@
+cask 'local-caffeine' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/local-transmission.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/local-transmission.rb
new file mode 100644
index 000000000..6709ac12e
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/local-transmission.rb
@@ -0,0 +1,9 @@
+cask 'local-transmission' do
+  version '2.61'
+  sha256 'e44ffa103fbf83f55c8d0b1bea309a43b2880798dae8620b1ee8da5e1095ec68'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/transmission-2.61.dmg"
+  homepage 'http://example.com/local-transmission'
+
+  app 'Transmission.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/missing-checksum.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/missing-checksum.rb
new file mode 100644
index 000000000..907b1375f
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/missing-checksum.rb
@@ -0,0 +1,8 @@
+cask 'missing-checksum' do
+  version '1.2.3'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/missing-homepage.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/missing-homepage.rb
new file mode 100644
index 000000000..cf06d6c33
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/missing-homepage.rb
@@ -0,0 +1,5 @@
+cask 'missing-homepage' do
+  version '1.2.3'
+
+  url 'http://localhost/something.dmg'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/missing-name.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/missing-name.rb
new file mode 100644
index 000000000..0801f4abb
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/missing-name.rb
@@ -0,0 +1,5 @@
+cask 'missing-name' do
+  version '1.2.3'
+
+  url 'http://localhost/something.dmg'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/missing-sha256.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/missing-sha256.rb
new file mode 100644
index 000000000..e6e6d9d20
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/missing-sha256.rb
@@ -0,0 +1,5 @@
+cask 'missing-sha256' do
+  version '1.2.3'
+
+  url 'http://localhost/something.dmg'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/missing-url.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/missing-url.rb
new file mode 100644
index 000000000..0bfaec332
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/missing-url.rb
@@ -0,0 +1,5 @@
+cask 'missing-url' do
+  version '1.2.3'
+
+  homepage 'http://example.com'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/missing-version.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/missing-version.rb
new file mode 100644
index 000000000..88e13d8bb
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/missing-version.rb
@@ -0,0 +1,4 @@
+cask 'missing-version' do
+  url 'http://localhost/something.dmg'
+  homepage 'http://example.com'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/naked-executable.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/naked-executable.rb
new file mode 100644
index 000000000..2f4e30dc1
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/naked-executable.rb
@@ -0,0 +1,9 @@
+cask 'naked-executable' do
+  version '1.2.3'
+  sha256 '306c6ca7407560340797866e077e053627ad409277d1b9da58106fce4cf717cb'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/naked_executable"
+  homepage 'http://example.com/naked-executable'
+
+  container type: :naked
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/nested-app.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/nested-app.rb
new file mode 100644
index 000000000..6061f7bff
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/nested-app.rb
@@ -0,0 +1,11 @@
+cask 'nested-app' do
+  version '1.2.3'
+  sha256 '1866dfa833b123bb8fe7fa7185ebf24d28d300d0643d75798bc23730af734216'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/NestedApp.dmg.zip"
+  homepage 'http://example.com/nested-app'
+
+  container nested: 'NestedApp.dmg'
+
+  app 'MyNestedApp.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/no-checksum.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/no-checksum.rb
new file mode 100644
index 000000000..1e06c6168
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/no-checksum.rb
@@ -0,0 +1,9 @@
+cask 'no-checksum' do
+  version '1.2.3'
+  sha256 :no_check
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/no-dsl-version.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/no-dsl-version.rb
new file mode 100644
index 000000000..3bafa171d
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/no-dsl-version.rb
@@ -0,0 +1,9 @@
+cask 'no-dsl-version' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url 'http://example.com/TestCask.dmg'
+  homepage 'http://example.com/'
+
+  app 'TestCask.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/osdn-correct-url-format.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/osdn-correct-url-format.rb
new file mode 100644
index 000000000..7e60fc179
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/osdn-correct-url-format.rb
@@ -0,0 +1,6 @@
+cask 'osdn-correct-url-format' do
+  version '1.2.3'
+
+  url 'http://user.dl.osdn.jp/something/id/Something-1.2.3.dmg'
+  homepage 'http://osdn.jp/projects/something/'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/osdn-incorrect-url-format.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/osdn-incorrect-url-format.rb
new file mode 100644
index 000000000..68b4ecd4c
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/osdn-incorrect-url-format.rb
@@ -0,0 +1,6 @@
+cask 'osdn-incorrect-url-format' do
+  version '1.2.3'
+
+  url 'http://osdn.jp/projects/something/files/Something-1.2.3.dmg/download'
+  homepage 'http://osdn.jp/projects/something/'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/sha256-for-empty-string.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/sha256-for-empty-string.rb
new file mode 100644
index 000000000..0bf3ee9b5
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/sha256-for-empty-string.rb
@@ -0,0 +1,4 @@
+cask 'sha256-for-empty-string' do
+  version '1.2.3'
+  sha256 'e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/sourceforge-correct-url-format.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/sourceforge-correct-url-format.rb
new file mode 100644
index 000000000..439eb8998
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/sourceforge-correct-url-format.rb
@@ -0,0 +1,6 @@
+cask 'sourceforge-correct-url-format' do
+  version '1.2.3'
+
+  url 'https://downloads.sourceforge.net/something/Something-1.2.3.dmg'
+  homepage 'https://sourceforge.net/projects/something/'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/sourceforge-incorrect-url-format.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/sourceforge-incorrect-url-format.rb
new file mode 100644
index 000000000..39ac52414
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/sourceforge-incorrect-url-format.rb
@@ -0,0 +1,6 @@
+cask 'sourceforge-incorrect-url-format' do
+  version '1.2.3'
+
+  url 'http://sourceforge.net/projects/something/files/Something-1.2.3.dmg/download'
+  homepage 'http://sourceforge.net/projects/something/'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/sourceforge-version-latest-correct-url-format.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/sourceforge-version-latest-correct-url-format.rb
new file mode 100644
index 000000000..07b068f70
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/sourceforge-version-latest-correct-url-format.rb
@@ -0,0 +1,6 @@
+cask 'sourceforge-version-latest-correct-url-format' do
+  version :latest
+
+  url 'https://sourceforge.net/projects/something/files/latest/download'
+  homepage 'https://sourceforge.net/projects/something/'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/stage-only.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/stage-only.rb
new file mode 100644
index 000000000..941e2084f
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/stage-only.rb
@@ -0,0 +1,9 @@
+cask 'stage-only' do
+  version '2.61'
+  sha256 'e44ffa103fbf83f55c8d0b1bea309a43b2880798dae8620b1ee8da5e1095ec68'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/transmission-2.61.dmg"
+  homepage 'http://example.com/stage-only'
+
+  stage_only true
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/test-opera-mail.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/test-opera-mail.rb
new file mode 100644
index 000000000..3e2c76e67
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/test-opera-mail.rb
@@ -0,0 +1,9 @@
+cask 'test-opera-mail' do
+  version '1.0'
+  sha256 'afd192e308f8ea8ddb3d426fd6663d97078570417ee78b8e1fa15f515ae3d677'
+
+  url 'http://get-ash-1.opera.com/pub/opera/mail/1.0/mac/Opera-Mail-1.0-1040.i386.dmg'
+  homepage 'http://www.opera.com/computer/mail'
+
+  app 'Opera Mail.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/test-opera.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/test-opera.rb
new file mode 100644
index 000000000..7ca0157d9
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/test-opera.rb
@@ -0,0 +1,9 @@
+cask 'test-opera' do
+  version '19.0.1326.47'
+  sha256 '7b91f20ab754f7b3fef8dc346e0393917e11676b74c8f577408841619f76040a'
+
+  url 'http://get.geo.opera.com/pub/opera/desktop/19.0.1326.47/mac/Opera_19.0.1326.47_Setup.dmg'
+  homepage 'http://www.opera.com/'
+
+  app 'Opera.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/version-latest-string.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/version-latest-string.rb
new file mode 100644
index 000000000..6bd090c28
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/version-latest-string.rb
@@ -0,0 +1,4 @@
+cask 'version-latest-string' do
+  version 'latest'
+  sha256 :no_check
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/version-latest-with-checksum.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/version-latest-with-checksum.rb
new file mode 100644
index 000000000..040cfc76e
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/version-latest-with-checksum.rb
@@ -0,0 +1,4 @@
+cask 'version-latest-with-checksum' do
+  version :latest
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-accessibility-access.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-accessibility-access.rb
new file mode 100644
index 000000000..4c1c9897a
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-accessibility-access.rb
@@ -0,0 +1,11 @@
+cask 'with-accessibility-access' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url 'http://example.com/TestCask.dmg'
+  homepage 'http://example.com/'
+
+  accessibility_access true
+
+  app 'TestCask.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-alt-target.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-alt-target.rb
new file mode 100644
index 000000000..7a6d75a9c
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-alt-target.rb
@@ -0,0 +1,9 @@
+cask 'with-alt-target' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeine.app', target: 'AnotherName.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-appcast.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-appcast.rb
new file mode 100644
index 000000000..fc57e5e65
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-appcast.rb
@@ -0,0 +1,11 @@
+cask 'with-appcast' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  appcast 'http://example.com/appcast.xml',
+          checkpoint: '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+  homepage 'http://example.com/with-appcast'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-binary.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-binary.rb
new file mode 100644
index 000000000..38be2e772
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-binary.rb
@@ -0,0 +1,10 @@
+cask 'with-binary' do
+  version '1.2.3'
+  sha256 'd5b2dfbef7ea28c25f7a77cd7fa14d013d82b626db1d82e00e25822464ba19e2'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/AppWithBinary.zip"
+  homepage 'http://example.com/with-binary'
+
+  app 'App.app'
+  binary 'binary'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-caveats.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-caveats.rb
new file mode 100644
index 000000000..d5d90114a
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-caveats.rb
@@ -0,0 +1,23 @@
+cask 'with-caveats' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeine.app'
+
+  # simple string is evaluated at compile-time
+  caveats <<-EOS.undent
+    Here are some things you might want to know.
+  EOS
+  # do block is evaluated at install-time
+  caveats do
+    "Cask token: #{token}"
+  end
+  # a do block may print and use a DSL
+  caveats do
+    puts 'Custom text via puts followed by DSL-generated text:'
+    path_environment_variable('/custom/path/bin')
+  end
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-choices.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-choices.rb
new file mode 100644
index 000000000..640a3bbb3
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-choices.rb
@@ -0,0 +1,16 @@
+cask 'with-choices' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg',
+      choices: [
+                 {
+                   'choiceIdentifier' => 'choice1',
+                   'choiceAttribute'  => 'selected',
+                   'attributeSetting' => 1,
+                 },
+               ]
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-conditional-caveats.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-conditional-caveats.rb
new file mode 100644
index 000000000..e3c666834
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-conditional-caveats.rb
@@ -0,0 +1,14 @@
+cask 'with-conditional-caveats' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeine.app'
+
+  # a do block may print and use a DSL
+  caveats do
+    puts 'This caveat is conditional' if false # rubocop:disable Lint/LiteralInCondition
+  end
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-conflicts-with.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-conflicts-with.rb
new file mode 100644
index 000000000..ab3631743
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-conflicts-with.rb
@@ -0,0 +1,11 @@
+cask 'with-conflicts-with' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-conflicts-with'
+
+  conflicts_with formula: 'unar'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-arch.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-arch.rb
new file mode 100644
index 000000000..9fe0d043b
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-arch.rb
@@ -0,0 +1,12 @@
+cask 'with-depends-on-arch' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-depends-on-arch'
+
+  # covers all known hardware; always succeeds
+  depends_on arch: :intel
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-cask-cyclic-helper.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-cask-cyclic-helper.rb
new file mode 100644
index 000000000..3a90295e5
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-cask-cyclic-helper.rb
@@ -0,0 +1,11 @@
+cask 'with-depends-on-cask-cyclic-helper' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-depends-on-cask-cyclic-helper'
+
+  depends_on cask: 'with-depends-on-cask-cyclic'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-cask-cyclic.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-cask-cyclic.rb
new file mode 100644
index 000000000..776351568
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-cask-cyclic.rb
@@ -0,0 +1,12 @@
+cask 'with-depends-on-cask-cyclic' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-depends-on-cask-cyclic'
+
+  depends_on cask: 'local-caffeine'
+  depends_on cask: 'with-depends-on-cask-cyclic-helper'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-cask-multiple.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-cask-multiple.rb
new file mode 100644
index 000000000..74e1c2747
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-cask-multiple.rb
@@ -0,0 +1,12 @@
+cask 'with-depends-on-cask-multiple' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-depends-on-cask-multiple'
+
+  depends_on cask: 'local-caffeine'
+  depends_on cask: 'local-transmission'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-cask.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-cask.rb
new file mode 100644
index 000000000..52daec865
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-cask.rb
@@ -0,0 +1,11 @@
+cask 'with-depends-on-cask' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-depends-on-cask'
+
+  depends_on cask: 'local-transmission'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-formula-multiple.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-formula-multiple.rb
new file mode 100644
index 000000000..07d7bb86a
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-formula-multiple.rb
@@ -0,0 +1,12 @@
+cask 'with-depends-on-formula-multiple' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-depends-on-formula-multiple'
+
+  depends_on formula: 'unar'
+  depends_on formula: 'fileutils'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-formula.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-formula.rb
new file mode 100644
index 000000000..ac980f890
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-formula.rb
@@ -0,0 +1,11 @@
+cask 'with-depends-on-formula' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-depends-on-formula'
+
+  depends_on formula: 'unar'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-array.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-array.rb
new file mode 100644
index 000000000..7fb1a9016
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-array.rb
@@ -0,0 +1,12 @@
+cask 'with-depends-on-macos-array' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-depends-on-macos-array'
+
+  # since all OS releases are included, this should always pass
+  depends_on macos: ['10.4', '10.5', '10.6', '10.7', '10.8', '10.9', '10.10', MacOS.version.to_s]
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-comparison.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-comparison.rb
new file mode 100644
index 000000000..1483bcf74
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-comparison.rb
@@ -0,0 +1,11 @@
+cask 'with-depends-on-macos-comparison' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-depends-on-macos-comparison'
+
+  depends_on macos: '>= 10.4'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-failure.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-failure.rb
new file mode 100644
index 000000000..483d75814
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-failure.rb
@@ -0,0 +1,12 @@
+cask 'with-depends-on-macos-failure' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-depends-on-macos-failure'
+
+  # guarantee a mismatched release
+  depends_on macos: MacOS.version.to_s == '10.4' ? '10.5' : '10.4'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-string.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-string.rb
new file mode 100644
index 000000000..887771fe2
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-string.rb
@@ -0,0 +1,11 @@
+cask 'with-depends-on-macos-string' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-depends-on-macos-string'
+
+  depends_on macos: MacOS.version.to_s
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-symbol.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-symbol.rb
new file mode 100644
index 000000000..e5aa05d23
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-symbol.rb
@@ -0,0 +1,11 @@
+cask 'with-depends-on-macos-symbol' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-depends-on-macos-symbol'
+
+  depends_on macos: MacOS.version.to_sym
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-x11-false.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-x11-false.rb
new file mode 100644
index 000000000..d5107edc5
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-x11-false.rb
@@ -0,0 +1,11 @@
+cask 'with-depends-on-x11-false' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-depends-on-x11-false'
+
+  depends_on x11: false
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-x11.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-x11.rb
new file mode 100644
index 000000000..bcb781637
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-x11.rb
@@ -0,0 +1,11 @@
+cask 'with-depends-on-x11' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-depends-on-x11'
+
+  depends_on x11: true
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-dsl-version.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-dsl-version.rb
new file mode 100644
index 000000000..15f0319c5
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-dsl-version.rb
@@ -0,0 +1,9 @@
+cask :v1 => 'with-dsl-version' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url 'http://example.com/TestCask.dmg'
+  homepage 'http://example.com/'
+
+  app 'TestCask.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-embedded-binary.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-embedded-binary.rb
new file mode 100644
index 000000000..5987bbfe6
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-embedded-binary.rb
@@ -0,0 +1,10 @@
+cask 'with-embedded-binary' do
+  version '1.2.3'
+  sha256 'fe052d3e77d92676775fd916ddb8942e72a565b844ea7f6d055474c99bb4e47b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/AppWithEmbeddedBinary.zip"
+  homepage 'http://example.com/with-binary'
+
+  app 'App.app'
+  binary "#{appdir}/App.app/Contents/MacOS/App/binary"
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-generic-artifact-no-target.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-generic-artifact-no-target.rb
new file mode 100644
index 000000000..f7f1ddc22
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-generic-artifact-no-target.rb
@@ -0,0 +1,9 @@
+cask 'with-generic-artifact-no-target' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-generic-artifact'
+
+  artifact 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-generic-artifact.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-generic-artifact.rb
new file mode 100644
index 000000000..d6ce0ce8d
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-generic-artifact.rb
@@ -0,0 +1,9 @@
+cask 'with-generic-artifact' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-generic-artifact'
+
+  artifact 'Caffeine.app', target: "#{Hbc.appdir}/Caffeine.app"
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-gpg-key-url.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-gpg-key-url.rb
new file mode 100644
index 000000000..fc0c9ddfc
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-gpg-key-url.rb
@@ -0,0 +1,11 @@
+cask 'with-gpg-key-url' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-gpg-key-url'
+  gpg 'http://example.com/gpg-signature.asc',
+      key_url: 'http://example.com/gpg-key-url'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-gpg.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-gpg.rb
new file mode 100644
index 000000000..e07546b94
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-gpg.rb
@@ -0,0 +1,11 @@
+cask 'with-gpg' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-gpg'
+  gpg 'http://example.com/gpg-signature.asc',
+      key_id: '01234567'
+
+  app 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-installable.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-installable.rb
new file mode 100644
index 000000000..8416f3f88
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-installable.rb
@@ -0,0 +1,21 @@
+cask 'with-installable' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg'
+
+  uninstall script:     { executable: 'MyFancyPkg/FancyUninstaller.tool', args: %w[--please] },
+            quit:       'my.fancy.package.app',
+            login_item: 'Fancy',
+            delete:     [
+                          "#{TEST_TMPDIR}/absolute_path",
+                          '~/path_with_tilde',
+                          "#{TEST_TMPDIR}/glob_path*",
+                          'impermissible/relative/path',
+                          '/another/impermissible/../relative/path',
+                        ],
+            rmdir:      "#{TEST_TMPDIR}/empty_directory_path"
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-installer-manual.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-installer-manual.rb
new file mode 100644
index 000000000..a857b6900
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-installer-manual.rb
@@ -0,0 +1,9 @@
+cask 'with-installer-manual' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  installer manual: 'Caffeine.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-installer-script.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-installer-script.rb
new file mode 100644
index 000000000..b32d131e0
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-installer-script.rb
@@ -0,0 +1,15 @@
+cask 'with-installer-script' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/with-install-script'
+
+  installer script: '/usr/bin/true',
+            args:   ['--flag']
+  # acceptable alternate form
+  installer script: {
+                      executable: '/usr/bin/false',
+                      args:       ['--flag'],
+                    }
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-macosx-dir.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-macosx-dir.rb
new file mode 100644
index 000000000..505e9f5a7
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-macosx-dir.rb
@@ -0,0 +1,9 @@
+cask 'with-macosx-dir' do
+  version '1.2.3'
+  sha256 '5633c3a0f2e572cbf021507dec78c50998b398c343232bdfc7e26221d0a5db4d'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyApp.zip"
+  homepage 'http://example.com/MyFancyApp'
+
+  app 'MyFancyApp/MyFancyApp.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-pkgutil-zap.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-pkgutil-zap.rb
new file mode 100644
index 000000000..d86d47126
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-pkgutil-zap.rb
@@ -0,0 +1,13 @@
+cask 'with-pkgutil-zap' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'Fancy.pkg'
+
+  zap pkgutil:   'my.fancy.package.*',
+      kext:      'my.fancy.package.kernelextension',
+      launchctl: 'my.fancy.package.service'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-suite.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-suite.rb
new file mode 100644
index 000000000..88158e10d
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-suite.rb
@@ -0,0 +1,10 @@
+cask 'with-suite' do
+  version '1.2.3'
+  sha256 'd95dcc12d4e5be0bc3cb9793c4b7e7f69a25f0b3c7418494b0c883957e6eeae4'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine-suite.zip"
+  name 'Caffeine'
+  homepage 'http://example.com/with-suite'
+
+  suite 'Caffeine'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-two-apps-correct.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-two-apps-correct.rb
new file mode 100644
index 000000000..3963d7790
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-two-apps-correct.rb
@@ -0,0 +1,10 @@
+cask 'with-two-apps-correct' do
+  version '1.2.3'
+  sha256 '3178fbfd1ea5d87a2a0662a4eb599ebc9a03888e73f37538d9f3f6ee69d2368e'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeines.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeine Mini.app'
+  app 'Caffeine Pro.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-two-apps-incorrect.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-two-apps-incorrect.rb
new file mode 100644
index 000000000..c3ca473bd
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-two-apps-incorrect.rb
@@ -0,0 +1,9 @@
+cask 'with-two-apps-incorrect' do
+  version '1.2.3'
+  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeine.app', 'Caffeine.app/Contents/MacOS/Caffeine'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-two-apps-subdir.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-two-apps-subdir.rb
new file mode 100644
index 000000000..879e6e4ce
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-two-apps-subdir.rb
@@ -0,0 +1,10 @@
+cask 'with-two-apps-subdir' do
+  version '1.2.3'
+  sha256 'd687c22a21c02bd8f07da9302c8292b93a04df9a929e3f04d09aea6c76f75c65'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/caffeines-subdir.zip"
+  homepage 'http://example.com/local-caffeine'
+
+  app 'Caffeines/Caffeine Mini.app'
+  app 'Caffeines/Caffeine Pro.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-delete.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-delete.rb
new file mode 100644
index 000000000..c7d2e4767
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-delete.rb
@@ -0,0 +1,17 @@
+cask 'with-uninstall-delete' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'Fancy.pkg'
+
+  uninstall delete: [
+                      "#{TEST_TMPDIR}/absolute_path",
+                      '~/path_with_tilde',
+                      "#{TEST_TMPDIR}/glob_path*",
+                      'impermissible/relative/path',
+                      '/another/impermissible/../relative/path',
+                    ]
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-early-script.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-early-script.rb
new file mode 100644
index 000000000..a9cec5b97
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-early-script.rb
@@ -0,0 +1,11 @@
+cask 'with-uninstall-early-script' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg'
+
+  uninstall early_script: { executable: 'MyFancyPkg/FancyUninstaller.tool', args: %w[--please] }
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-kext.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-kext.rb
new file mode 100644
index 000000000..9b27a1f36
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-kext.rb
@@ -0,0 +1,11 @@
+cask 'with-uninstall-kext' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'Fancy.pkg'
+
+  uninstall kext: 'my.fancy.package.kernelextension'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-launchctl.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-launchctl.rb
new file mode 100644
index 000000000..e5aa2b2d7
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-launchctl.rb
@@ -0,0 +1,11 @@
+cask 'with-uninstall-launchctl' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyApp.zip"
+  homepage 'http://example.com/fancy'
+
+  app 'Fancy.app'
+
+  uninstall launchctl: 'my.fancy.package.service'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-login-item.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-login-item.rb
new file mode 100644
index 000000000..46f1f9704
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-login-item.rb
@@ -0,0 +1,11 @@
+cask 'with-uninstall-login-item' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg'
+
+  uninstall login_item: 'Fancy'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-pkgutil.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-pkgutil.rb
new file mode 100644
index 000000000..00157322d
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-pkgutil.rb
@@ -0,0 +1,11 @@
+cask 'with-uninstall-pkgutil' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'Fancy.pkg'
+
+  uninstall pkgutil: 'my.fancy.package.*'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-quit.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-quit.rb
new file mode 100644
index 000000000..7f9515578
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-quit.rb
@@ -0,0 +1,11 @@
+cask 'with-uninstall-quit' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg'
+
+  uninstall quit: 'my.fancy.package.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-rmdir.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-rmdir.rb
new file mode 100644
index 000000000..8ded5b835
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-rmdir.rb
@@ -0,0 +1,11 @@
+cask 'with-uninstall-rmdir' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg'
+
+  uninstall rmdir: "#{TEST_TMPDIR}/empty_directory_path"
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-script-app.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-script-app.rb
new file mode 100644
index 000000000..f5f3ae5dd
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-script-app.rb
@@ -0,0 +1,21 @@
+cask 'with-uninstall-script-app' do
+  version '1.2.3'
+  sha256 '5633c3a0f2e572cbf021507dec78c50998b398c343232bdfc7e26221d0a5db4d'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyApp.zip"
+  homepage 'http://example.com/MyFancyApp'
+
+  app 'MyFancyApp/MyFancyApp.app'
+
+  postflight do
+    IO.write "#{appdir}/MyFancyApp.app/uninstall.sh", <<-EOS.undent
+      #!/bin/sh
+      /bin/rm -r "#{appdir}/MyFancyApp.app"
+    EOS
+  end
+
+  uninstall script: {
+                      executable: "#{appdir}/MyFancyApp.app/uninstall.sh",
+                      sudo: false
+                    }
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-script.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-script.rb
new file mode 100644
index 000000000..3e2dd0bb9
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-script.rb
@@ -0,0 +1,11 @@
+cask 'with-uninstall-script' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg'
+
+  uninstall script: { executable: 'MyFancyPkg/FancyUninstaller.tool', args: %w[--please] }
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-signal.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-signal.rb
new file mode 100644
index 000000000..850055c3c
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-signal.rb
@@ -0,0 +1,14 @@
+cask 'with-uninstall-signal' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg'
+
+  uninstall signal: [
+                      ['TERM', 'my.fancy.package.app'],
+                      ['KILL', 'my.fancy.package.app'],
+                    ]
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-trash.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-trash.rb
new file mode 100644
index 000000000..b085b3e32
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-uninstall-trash.rb
@@ -0,0 +1,17 @@
+cask 'with-uninstall-trash' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'Fancy.pkg'
+
+  uninstall trash: [
+                     "#{TEST_TMPDIR}/absolute_path",
+                     '~/path_with_tilde',
+                     "#{TEST_TMPDIR}/glob_path*",
+                     'impermissible/relative/path',
+                     '/another/impermissible/../relative/path',
+                   ]
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-delete.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-delete.rb
new file mode 100644
index 000000000..d81a387f9
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-delete.rb
@@ -0,0 +1,17 @@
+cask 'with-zap-delete' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'Fancy.pkg'
+
+  zap delete: [
+                "#{TEST_TMPDIR}/absolute_path",
+                '~/path_with_tilde',
+                "#{TEST_TMPDIR}/glob_path*",
+                'impermissible/relative/path',
+                '/another/impermissible/../relative/path',
+              ]
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-early-script.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-early-script.rb
new file mode 100644
index 000000000..9375d2cc7
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-early-script.rb
@@ -0,0 +1,11 @@
+cask 'with-zap-early-script' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg'
+
+  zap early_script: { executable: 'MyFancyPkg/FancyUninstaller.tool', args: %w[--please] }
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-kext.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-kext.rb
new file mode 100644
index 000000000..e9c29f619
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-kext.rb
@@ -0,0 +1,11 @@
+cask 'with-zap-kext' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'Fancy.pkg'
+
+  zap kext: 'my.fancy.package.kernelextension'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-launchctl.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-launchctl.rb
new file mode 100644
index 000000000..6d17ccfb0
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-launchctl.rb
@@ -0,0 +1,11 @@
+cask 'with-zap-launchctl' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyApp.zip"
+  homepage 'http://example.com/fancy'
+
+  app 'Fancy.app'
+
+  zap launchctl: 'my.fancy.package.service'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-login-item.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-login-item.rb
new file mode 100644
index 000000000..2715892ef
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-login-item.rb
@@ -0,0 +1,11 @@
+cask 'with-zap-login-item' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg'
+
+  zap login_item: 'Fancy'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-pkgutil.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-pkgutil.rb
new file mode 100644
index 000000000..c7f08b76d
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-pkgutil.rb
@@ -0,0 +1,11 @@
+cask 'with-zap-pkgutil' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'Fancy.pkg'
+
+  zap pkgutil: 'my.fancy.package.*'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-quit.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-quit.rb
new file mode 100644
index 000000000..4e4ab3a85
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-quit.rb
@@ -0,0 +1,11 @@
+cask 'with-zap-quit' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg'
+
+  zap quit: 'my.fancy.package.app'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-rmdir.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-rmdir.rb
new file mode 100644
index 000000000..a67c4ca9a
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-rmdir.rb
@@ -0,0 +1,11 @@
+cask 'with-zap-rmdir' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg'
+
+  zap rmdir: "#{TEST_TMPDIR}/empty_directory_path"
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-script.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-script.rb
new file mode 100644
index 000000000..5e033301a
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-script.rb
@@ -0,0 +1,11 @@
+cask 'with-zap-script' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg'
+
+  zap script: { executable: 'MyFancyPkg/FancyUninstaller.tool', args: %w[--please] }
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-signal.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-signal.rb
new file mode 100644
index 000000000..47870cf05
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-signal.rb
@@ -0,0 +1,14 @@
+cask 'with-zap-signal' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg'
+
+  zap signal: [
+                ['TERM', 'my.fancy.package.app'],
+                ['KILL', 'my.fancy.package.app'],
+              ]
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-trash.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-trash.rb
new file mode 100644
index 000000000..ea2bc2a01
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap-trash.rb
@@ -0,0 +1,17 @@
+cask 'with-zap-trash' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'Fancy.pkg'
+
+  zap trash: [
+               "#{TEST_TMPDIR}/absolute_path",
+               '~/path_with_tilde',
+               "#{TEST_TMPDIR}/glob_path*",
+               'impermissible/relative/path',
+               '/another/impermissible/../relative/path',
+             ]
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap.rb b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap.rb
new file mode 100644
index 000000000..275516fba
--- /dev/null
+++ b/Library/Homebrew/test/support/fixtures/cask/Casks/with-zap.rb
@@ -0,0 +1,19 @@
+cask 'with-zap' do
+  version '1.2.3'
+  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyPkg.zip"
+  homepage 'http://example.com/fancy-pkg'
+
+  pkg 'MyFancyPkg/Fancy.pkg'
+
+  uninstall quit: 'my.fancy.package.app.from.uninstall'
+
+  zap script:     {
+                    executable: 'MyFancyPkg/FancyUninstaller.tool',
+                    args:       %w[--please],
+                  },
+      quit:       'my.fancy.package.app',
+      login_item: 'Fancy',
+      delete:     '~/Library/Preferences/my.fancy.app.plist'
+end
diff --git a/Library/Homebrew/test/support/fixtures/cask/empty_directory/.gitignore b/Library/Homebrew/test/support/fixtures/cask/empty_directory/.gitignore
deleted file mode 100644
index e69de29bb..000000000
--- a/Library/Homebrew/test/support/fixtures/cask/empty_directory/.gitignore
+++ /dev/null
diff --git a/Library/Homebrew/test/support/helper/env.rb b/Library/Homebrew/test/support/helper/env.rb
deleted file mode 100644
index 904a1d4c7..000000000
--- a/Library/Homebrew/test/support/helper/env.rb
+++ /dev/null
@@ -1,15 +0,0 @@
-module Test
-  module Helper
-    module Env
-      def with_environment(partial_env)
-        old = ENV.to_hash
-        ENV.update partial_env
-        begin
-          yield
-        ensure
-          ENV.replace old
-        end
-      end
-    end
-  end
-end
diff --git a/Library/Homebrew/test/support/helper/fixtures.rb b/Library/Homebrew/test/support/helper/fixtures.rb
new file mode 100644
index 000000000..716fe2008
--- /dev/null
+++ b/Library/Homebrew/test/support/helper/fixtures.rb
@@ -0,0 +1,13 @@
+module Test
+  module Helper
+    module Fixtures
+      def dylib_path(name)
+        Pathname.new("#{TEST_FIXTURE_DIR}/mach/#{name}.dylib")
+      end
+
+      def bundle_path(name)
+        Pathname.new("#{TEST_FIXTURE_DIR}/mach/#{name}.bundle")
+      end
+    end
+  end
+end
diff --git a/Library/Homebrew/test/support/helper/formula.rb b/Library/Homebrew/test/support/helper/formula.rb
new file mode 100644
index 000000000..7f55f4b66
--- /dev/null
+++ b/Library/Homebrew/test/support/helper/formula.rb
@@ -0,0 +1,19 @@
+require "formulary"
+
+module Test
+  module Helper
+    module Formula
+      def formula(name = "formula_name", path: Formulary.core_path(name), spec: :stable, alias_path: nil, &block)
+        Class.new(::Formula, &block).new(name, path, spec, alias_path: alias_path)
+      end
+
+      # Use a stubbed {Formulary::FormulaLoader} to make a given formula be found
+      # when loading from {Formulary} with `ref`.
+      def stub_formula_loader(formula, ref = formula.full_name)
+        loader = double(get_formula: formula)
+        allow(Formulary).to receive(:loader_for).with(ref, from: :keg).and_return(loader)
+        allow(Formulary).to receive(:loader_for).with(ref, from: nil).and_return(loader)
+      end
+    end
+  end
+end
diff --git a/Library/Homebrew/test/support/helper/fs_leak_logger.rb b/Library/Homebrew/test/support/helper/fs_leak_logger.rb
index 774ccda04..3fbb148fa 100644
--- a/Library/Homebrew/test/support/helper/fs_leak_logger.rb
+++ b/Library/Homebrew/test/support/helper/fs_leak_logger.rb
@@ -9,13 +9,13 @@ module Test
         klass.make_my_diffs_pretty!
       end
 
-      def before_setup
+      def setup
         @__files_before_test = []
         Find.find(TEST_TMPDIR) { |f| @__files_before_test << f.sub(TEST_TMPDIR, "") }
         super
       end
 
-      def after_teardown
+      def teardown
         super
         files_after_test = []
         Find.find(TEST_TMPDIR) { |f| files_after_test << f.sub(TEST_TMPDIR, "") }
diff --git a/Library/Homebrew/test/support/helper/integration_command_test_case.rb b/Library/Homebrew/test/support/helper/integration_command_test_case.rb
index b79fdd6e0..7ba094645 100644
--- a/Library/Homebrew/test/support/helper/integration_command_test_case.rb
+++ b/Library/Homebrew/test/support/helper/integration_command_test_case.rb
@@ -3,43 +3,16 @@ require "fileutils"
 require "pathname"
 require "formula"
 require "test/support/helper/test_case"
+require "open3"
 
 class IntegrationCommandTestCase < Homebrew::TestCase
   def setup
+    super
     @cmd_id_index = 0 # Assign unique IDs to invocations of `cmd_output`.
     (HOMEBREW_PREFIX/"bin").mkpath
     FileUtils.touch HOMEBREW_PREFIX/"bin/brew"
   end
 
-  def teardown
-    coretap = CoreTap.new
-    paths_to_delete = [
-      HOMEBREW_LINKED_KEGS,
-      HOMEBREW_PINNED_KEGS,
-      HOMEBREW_CELLAR.children,
-      HOMEBREW_CACHE.children,
-      HOMEBREW_LOCK_DIR.children,
-      HOMEBREW_LOGS.children,
-      HOMEBREW_TEMP.children,
-      HOMEBREW_PREFIX/".git",
-      HOMEBREW_PREFIX/"bin",
-      HOMEBREW_PREFIX/"share",
-      HOMEBREW_PREFIX/"opt",
-      HOMEBREW_PREFIX/"Caskroom",
-      HOMEBREW_LIBRARY/"Taps/caskroom",
-      HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-bundle",
-      HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-foo",
-      HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-services",
-      HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-shallow",
-      HOMEBREW_REPOSITORY/".git",
-      coretap.path/".git",
-      coretap.alias_dir,
-      coretap.formula_dir.children,
-      coretap.path/"formula_renames.json",
-    ].flatten
-    FileUtils.rm_rf paths_to_delete
-  end
-
   def needs_test_cmd_taps
     return if ENV["HOMEBREW_TEST_OFFICIAL_CMD_TAPS"]
     skip "HOMEBREW_TEST_OFFICIAL_CMD_TAPS is not set"
@@ -56,66 +29,46 @@ class IntegrationCommandTestCase < Homebrew::TestCase
   end
 
   def cmd_output(*args)
-    # 1.8-compatible way of writing def cmd_output(*args, **env)
     env = args.last.is_a?(Hash) ? args.pop : {}
-    cmd_args = %W[
-      -W0
-      -I#{HOMEBREW_LIBRARY_PATH}/test/support/lib
-      -I#{HOMEBREW_LIBRARY_PATH}
-      -rconfig
+
+    env.merge!(
+      "HOMEBREW_BREW_FILE" => HOMEBREW_PREFIX/"bin/brew",
+      "HOMEBREW_INTEGRATION_TEST" => cmd_id_from_args(args),
+      "HOMEBREW_TEST_TMPDIR" => TEST_TMPDIR,
+      "HOMEBREW_DEVELOPER" => ENV["HOMEBREW_DEVELOPER"],
+    )
+
+    ruby_args = [
+      "-W0",
+      "-I", "#{HOMEBREW_LIBRARY_PATH}/test/support/lib",
+      "-I", HOMEBREW_LIBRARY_PATH.to_s,
+      "-rconfig"
     ]
-    if ENV["HOMEBREW_TESTS_COVERAGE"]
-      # This is needed only because we currently use a patched version of
-      # simplecov, and gems installed through git are not available without
-      # requiring bundler/setup first. See also the comment in test/Gemfile.
-      # Remove this line when we'll switch back to a stable simplecov release.
-      cmd_args << "-rbundler/setup"
-      cmd_args << "-rsimplecov"
-    end
-    cmd_args << "-rtest/support/helper/integration_mocks"
-    cmd_args << (HOMEBREW_LIBRARY_PATH/"brew.rb").resolved_path.to_s
-    cmd_args += args
-    developer = ENV["HOMEBREW_DEVELOPER"]
-    Bundler.with_original_env do
-      ENV["HOMEBREW_BREW_FILE"] = HOMEBREW_PREFIX/"bin/brew"
-      ENV["HOMEBREW_INTEGRATION_TEST"] = cmd_id_from_args(args)
-      ENV["HOMEBREW_TEST_TMPDIR"] = TEST_TMPDIR
-      ENV["HOMEBREW_DEVELOPER"] = developer
-      env.each_pair do |k, v|
-        ENV[k] = v
-      end
+    ruby_args << "-rsimplecov" if ENV["HOMEBREW_TESTS_COVERAGE"]
+    ruby_args << "-rtest/support/helper/integration_mocks"
+    ruby_args << (HOMEBREW_LIBRARY_PATH/"brew.rb").resolved_path.to_s
 
-      read, write = IO.pipe
-      begin
-        pid = fork do
-          read.close
-          $stdout.reopen(write)
-          $stderr.reopen(write)
-          write.close
-          exec RUBY_PATH, *cmd_args
-        end
-        write.close
-        read.read.chomp
-      ensure
-        Process.wait(pid)
-        read.close
-      end
+    Bundler.with_original_env do
+      output, status = Open3.capture2e(env, RUBY_PATH, *ruby_args, *args)
+      [output.chomp, status]
     end
   end
 
   def cmd(*args)
-    output = cmd_output(*args)
-    status = $?.exitstatus
-    puts "\n'brew #{args.join " "}' output: #{output}" if status.nonzero?
-    assert_equal 0, status
+    output, status = cmd_output(*args)
+    assert status.success?, <<-EOS.undent
+      `brew #{args.join " "}` exited with non-zero status!
+      #{output}
+    EOS
     output
   end
 
   def cmd_fail(*args)
-    output = cmd_output(*args)
-    status = $?.exitstatus
-    $stderr.puts "\n'brew #{args.join " "}'" if status.zero?
-    refute_equal 0, status
+    output, status = cmd_output(*args)
+    refute status.success?, <<-EOS.undent
+      `brew #{args.join " "}` exited with zero status!
+      #{output}
+    EOS
     output
   end
 
diff --git a/Library/Homebrew/test/support/helper/lifecycle_enforcer.rb b/Library/Homebrew/test/support/helper/lifecycle_enforcer.rb
new file mode 100644
index 000000000..413f8b11e
--- /dev/null
+++ b/Library/Homebrew/test/support/helper/lifecycle_enforcer.rb
@@ -0,0 +1,22 @@
+module Test
+  module Helper
+    module LifecycleEnforcer
+      def setup
+        @__setup_called = true
+        super
+      end
+
+      def teardown
+        @__teardown_called = true
+        super
+      end
+
+      def after_teardown
+        assert @__setup_called, "Expected setup to call `super` but didn't"
+        assert @__teardown_called, "Expected teardown to call `super` but didn't"
+
+        super
+      end
+    end
+  end
+end
diff --git a/Library/Homebrew/test/support/helper/spec/shared_context/integration_test.rb b/Library/Homebrew/test/support/helper/spec/shared_context/integration_test.rb
new file mode 100644
index 000000000..2eb98826a
--- /dev/null
+++ b/Library/Homebrew/test/support/helper/spec/shared_context/integration_test.rb
@@ -0,0 +1,176 @@
+require "rspec"
+require "open3"
+
+RSpec::Matchers.define_negated_matcher :not_to_output, :output
+RSpec::Matchers.define_negated_matcher :be_a_failure, :be_a_success
+
+RSpec.shared_context "integration test" do
+  extend RSpec::Matchers::DSL
+
+  matcher :be_a_success do
+    match do |actual|
+      status = actual.is_a?(Proc) ? actual.call : actual
+      status.respond_to?(:success?) && status.success?
+    end
+
+    def supports_block_expectations?
+      true
+    end
+
+    # It needs to be nested like this:
+    #
+    #   expect {
+    #     expect {
+    #       # command
+    #     }.to be_a_success
+    #   }.to output(something).to_stdout
+    #
+    # rather than this:
+    #
+    #   expect {
+    #     expect {
+    #       # command
+    #     }.to output(something).to_stdout
+    #   }.to be_a_success
+    #
+    def expects_call_stack_jump?
+      true
+    end
+  end
+
+  before(:each) do
+    (HOMEBREW_PREFIX/"bin").mkpath
+    FileUtils.touch HOMEBREW_PREFIX/"bin/brew"
+  end
+
+  after(:each) do
+    FileUtils.rm HOMEBREW_PREFIX/"bin/brew"
+    FileUtils.rmdir HOMEBREW_PREFIX/"bin"
+  end
+
+  # Generate unique ID to be able to
+  # properly merge coverage results.
+  def command_id_from_args(args)
+    @command_count ||= 0
+    pretty_args = args.join(" ").gsub(TEST_TMPDIR, "@TMPDIR@")
+    file_and_line = caller[1].sub(/(.*\d+):.*/, '\1')
+                             .sub("#{HOMEBREW_LIBRARY_PATH}/test/", "")
+    "#{file_and_line}:brew #{pretty_args}:#{@command_count += 1}"
+  end
+
+  # Runs a `brew` command with the test configuration
+  # and with coverage reporting enabled.
+  def brew(*args)
+    env = args.last.is_a?(Hash) ? args.pop : {}
+
+    # Avoid warnings when HOMEBREW_PREFIX/bin is not in PATH.
+    path = [
+      env["PATH"],
+      (HOMEBREW_PREFIX/"bin").realpath.to_s,
+      ENV["PATH"],
+    ].compact.join(File::PATH_SEPARATOR)
+
+    env.merge!(
+      "PATH" => path,
+      "HOMEBREW_BREW_FILE" => HOMEBREW_PREFIX/"bin/brew",
+      "HOMEBREW_INTEGRATION_TEST" => command_id_from_args(args),
+      "HOMEBREW_TEST_TMPDIR" => TEST_TMPDIR,
+      "HOMEBREW_DEVELOPER" => ENV["HOMEBREW_DEVELOPER"],
+    )
+
+    ruby_args = [
+      "-W0",
+      "-I", "#{HOMEBREW_LIBRARY_PATH}/test/support/lib",
+      "-I", HOMEBREW_LIBRARY_PATH.to_s,
+      "-rconfig"
+    ]
+    ruby_args << "-rsimplecov" if ENV["HOMEBREW_TESTS_COVERAGE"]
+    ruby_args << "-rtest/support/helper/integration_mocks"
+    ruby_args << (HOMEBREW_LIBRARY_PATH/"brew.rb").resolved_path.to_s
+
+    Bundler.with_original_env do
+      stdout, stderr, status = Open3.capture3(env, RUBY_PATH, *ruby_args, *args)
+      $stdout.print stdout
+      $stderr.print stderr
+      status
+    end
+  end
+
+  def setup_test_formula(name, content = nil)
+    case name
+    when /^testball/
+      content = <<-EOS.undent
+        desc "Some test"
+        homepage "https://example.com/#{name}"
+        url "file://#{TEST_FIXTURE_DIR}/tarballs/testball-0.1.tbz"
+        sha256 "#{TESTBALL_SHA256}"
+
+        option "with-foo", "Build with foo"
+
+        def install
+          (prefix/"foo"/"test").write("test") if build.with? "foo"
+          prefix.install Dir["*"]
+          (buildpath/"test.c").write \
+            "#include <stdio.h>\\nint main(){return printf(\\"test\\");}"
+          bin.mkpath
+          system ENV.cc, "test.c", "-o", bin/"test"
+        end
+
+        #{content}
+
+        # something here
+      EOS
+    when "foo"
+      content = <<-EOS.undent
+        url "https://example.com/#{name}-1.0"
+      EOS
+    when "bar"
+      content = <<-EOS.undent
+        url "https://example.com/#{name}-1.0"
+        depends_on "foo"
+      EOS
+    end
+
+    Formulary.core_path(name).tap do |formula_path|
+      formula_path.write <<-EOS.undent
+        class #{Formulary.class_s(name)} < Formula
+          #{content}
+        end
+      EOS
+    end
+  end
+
+  def setup_remote_tap(name)
+    Tap.fetch(name).tap do |tap|
+      tap.install(full_clone: false, quiet: true) unless tap.installed?
+    end
+  end
+
+  def install_and_rename_coretap_formula(old_name, new_name)
+    shutup do
+      CoreTap.instance.path.cd do |tap_path|
+        system "git", "init"
+        system "git", "add", "--all"
+        system "git", "commit", "-m",
+          "#{old_name.capitalize} has not yet been renamed"
+
+        brew "install", old_name
+
+        (tap_path/"Formula/#{old_name}.rb").unlink
+        (tap_path/"formula_renames.json").write JSON.generate(old_name => new_name)
+
+        system "git", "add", "--all"
+        system "git", "commit", "-m",
+          "#{old_name.capitalize} has been renamed to #{new_name.capitalize}"
+      end
+    end
+  end
+
+  def testball
+    "#{TEST_FIXTURE_DIR}/testball.rb"
+  end
+end
+
+RSpec.configure do |config|
+  config.include_context "integration test", :integration_test
+end
diff --git a/Library/Homebrew/test/support/helper/test_case.rb b/Library/Homebrew/test/support/helper/test_case.rb
index 60c91e7bb..568beb947 100644
--- a/Library/Homebrew/test/support/helper/test_case.rb
+++ b/Library/Homebrew/test/support/helper/test_case.rb
@@ -1,16 +1,66 @@
+require "formulary"
+require "tap"
+
 module Homebrew
   class TestCase < ::Minitest::Test
-    require "test/support/helper/env"
     require "test/support/helper/fs_leak_logger"
+    require "test/support/helper/lifecycle_enforcer"
     require "test/support/helper/shutup"
     require "test/support/helper/version_assertions"
-    include Test::Helper::Env
     include Test::Helper::FSLeakLogger
+    include Test::Helper::LifecycleEnforcer
     include Test::Helper::Shutup
     include Test::Helper::VersionAssertions
 
-    TEST_SHA1   = "deadbeefdeadbeefdeadbeefdeadbeefdeadbeef".freeze
-    TEST_SHA256 = "deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef".freeze
+    TEST_DIRECTORIES = [
+      CoreTap.instance.path/"Formula",
+      HOMEBREW_CACHE,
+      HOMEBREW_CACHE_FORMULA,
+      HOMEBREW_CELLAR,
+      HOMEBREW_LOCK_DIR,
+      HOMEBREW_LOGS,
+      HOMEBREW_TEMP,
+    ].freeze
+
+    def setup
+      # These directories need to be created before
+      # `FSLeakLogger` is called with `super`.
+      TEST_DIRECTORIES.each(&:mkpath)
+
+      super
+
+      @__argv = ARGV.dup
+      @__env = ENV.to_hash # dup doesn't work on ENV
+    end
+
+    def teardown
+      ARGV.replace(@__argv)
+      ENV.replace(@__env)
+
+      Tab.clear_cache
+
+      FileUtils.rm_rf [
+        TEST_DIRECTORIES.map(&:children),
+        HOMEBREW_LINKED_KEGS,
+        HOMEBREW_PINNED_KEGS,
+        HOMEBREW_PREFIX/".git",
+        HOMEBREW_PREFIX/"bin",
+        HOMEBREW_PREFIX/"share",
+        HOMEBREW_PREFIX/"opt",
+        HOMEBREW_PREFIX/"Caskroom",
+        HOMEBREW_LIBRARY/"Taps/caskroom",
+        HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-bundle",
+        HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-foo",
+        HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-services",
+        HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-shallow",
+        HOMEBREW_REPOSITORY/".git",
+        CoreTap.instance.path/".git",
+        CoreTap.instance.alias_dir,
+        CoreTap.instance.path/"formula_renames.json",
+      ]
+
+      super
+    end
 
     def formula(name = "formula_name", path = Formulary.core_path(name), spec = :stable, alias_path: nil, &block)
       @_f = Class.new(Formula, &block).new(name, path, spec, alias_path: alias_path)
diff --git a/Library/Homebrew/test/support/lib/config.rb b/Library/Homebrew/test/support/lib/config.rb
index f6fdb4ecb..3a0a76722 100644
--- a/Library/Homebrew/test/support/lib/config.rb
+++ b/Library/Homebrew/test/support/lib/config.rb
@@ -2,6 +2,8 @@ unless ENV["HOMEBREW_BREW_FILE"]
   raise "HOMEBREW_BREW_FILE was not exported! Please call bin/brew directly!"
 end
 
+require "constants"
+
 require "tmpdir"
 require "pathname"
 
@@ -38,3 +40,6 @@ TESTBALL_SHA256 = "91e3f7930c98d7ccfb288e115ed52d06b0e5bc16fec7dce8bdda865300270
 TESTBALL_PATCHES_SHA256 = "799c2d551ac5c3a5759bea7796631a7906a6a24435b52261a317133a0bfb34d9".freeze
 PATCH_A_SHA256 = "83404f4936d3257e65f176c4ffb5a5b8d6edd644a21c8d8dcc73e22a6d28fcfa".freeze
 PATCH_B_SHA256 = "57958271bb802a59452d0816e0670d16c8b70bdf6530bcf6f78726489ad89b90".freeze
+
+TEST_SHA1   = "deadbeefdeadbeefdeadbeefdeadbeefdeadbeef".freeze
+TEST_SHA256 = "deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef".freeze
diff --git a/Library/Homebrew/test/switch_test.rb b/Library/Homebrew/test/switch_test.rb
deleted file mode 100644
index af1926c39..000000000
--- a/Library/Homebrew/test/switch_test.rb
+++ /dev/null
@@ -1,20 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestSwitch < IntegrationCommandTestCase
-  def test_switch
-    assert_match "Usage: brew switch <name> <version>", cmd_fail("switch")
-    assert_match "testball not found", cmd_fail("switch", "testball", "0.1")
-
-    setup_test_formula "testball", <<-EOS.undent
-      keg_only "just because"
-    EOS
-
-    cmd("install", "testball")
-    testball_rack = HOMEBREW_CELLAR/"testball"
-    FileUtils.cp_r testball_rack/"0.1", testball_rack/"0.2"
-
-    cmd("switch", "testball", "0.2")
-    assert_match "testball does not have a version \"0.3\"",
-      cmd_fail("switch", "testball", "0.3")
-  end
-end
diff --git a/Library/Homebrew/test/tab_spec.rb b/Library/Homebrew/test/tab_spec.rb
new file mode 100644
index 000000000..01dbeb67c
--- /dev/null
+++ b/Library/Homebrew/test/tab_spec.rb
@@ -0,0 +1,341 @@
+require "tab"
+require "formula"
+
+RSpec::Matchers.alias_matcher :be_built_with, :be_with
+
+describe Tab do
+  matcher :be_poured_from_bottle do
+    match do |actual|
+      actual.poured_from_bottle == true
+    end
+  end
+
+  matcher :be_built_as_bottle do
+    match do |actual|
+      actual.built_as_bottle == true
+    end
+  end
+
+  subject {
+    described_class.new(
+      "homebrew_version" => HOMEBREW_VERSION,
+      "used_options"         => used_options.as_flags,
+      "unused_options"       => unused_options.as_flags,
+      "built_as_bottle"      => false,
+      "poured_from_bottle"   => true,
+      "changed_files"        => [],
+      "time"                 => time,
+      "source_modified_time" => 0,
+      "HEAD"                 => TEST_SHA1,
+      "compiler"             => "clang",
+      "stdlib"               => "libcxx",
+      "runtime_dependencies" => [],
+      "source"               => {
+        "tap" => CoreTap.instance.to_s,
+        "path" => CoreTap.instance.path.to_s,
+        "spec" => "stable",
+        "versions" => {
+          "stable" => "0.10",
+          "devel" => "0.14",
+          "head" => "HEAD-1111111",
+        },
+      },
+    )
+  }
+  let(:time) { Time.now.to_i }
+  let(:unused_options) { Options.create(%w[--with-baz --without-qux]) }
+  let(:used_options) { Options.create(%w[--with-foo --without-bar]) }
+
+  let(:f) { formula { url "foo-1.0" } }
+  let(:f_tab_path) { f.prefix/"INSTALL_RECEIPT.json" }
+  let(:f_tab_content) { (TEST_FIXTURE_DIR/"receipt.json").read }
+
+  specify "defaults" do
+    tab = described_class.empty
+
+    expect(tab.homebrew_version).to eq(HOMEBREW_VERSION)
+    expect(tab.unused_options).to be_empty
+    expect(tab.used_options).to be_empty
+    expect(tab.changed_files).to be nil
+    expect(tab).not_to be_built_as_bottle
+    expect(tab).not_to be_poured_from_bottle
+    expect(tab).to be_stable
+    expect(tab).not_to be_devel
+    expect(tab).not_to be_head
+    expect(tab.tap).to be nil
+    expect(tab.time).to be nil
+    expect(tab.HEAD).to be nil
+    expect(tab.runtime_dependencies).to be_empty
+    expect(tab.stable_version).to be nil
+    expect(tab.devel_version).to be nil
+    expect(tab.head_version).to be nil
+    expect(tab.cxxstdlib.compiler).to eq(DevelopmentTools.default_compiler)
+    expect(tab.cxxstdlib.type).to be nil
+    expect(tab.source["path"]).to be nil
+  end
+
+  specify "#include?" do
+    expect(subject).to include("with-foo")
+    expect(subject).to include("without-bar")
+  end
+
+  specify "#with?" do
+    expect(subject).to be_built_with("foo")
+    expect(subject).to be_built_with("qux")
+    expect(subject).not_to be_built_with("bar")
+    expect(subject).not_to be_built_with("baz")
+  end
+
+  specify "#universal?" do
+    tab = described_class.new(used_options: %w[--universal])
+    expect(tab).to be_universal
+  end
+
+  specify "#parsed_homebrew_version" do
+    tab = described_class.new
+    expect(tab.parsed_homebrew_version).to be Version::NULL
+
+    tab = described_class.new(homebrew_version: "1.2.3")
+    expect(tab.parsed_homebrew_version).to eq("1.2.3")
+    expect(tab.parsed_homebrew_version).to be < "1.2.3-1-g12789abdf"
+    expect(tab.parsed_homebrew_version).to be_kind_of(Version)
+
+    tab.homebrew_version = "1.2.4-567-g12789abdf"
+    expect(tab.parsed_homebrew_version).to be > "1.2.4"
+    expect(tab.parsed_homebrew_version).to be > "1.2.4-566-g21789abdf"
+    expect(tab.parsed_homebrew_version).to be < "1.2.4-568-g01789abdf"
+
+    tab = described_class.new(homebrew_version: "2.0.0-134-gabcdefabc-dirty")
+    expect(tab.parsed_homebrew_version).to be > "2.0.0"
+    expect(tab.parsed_homebrew_version).to be > "2.0.0-133-g21789abdf"
+    expect(tab.parsed_homebrew_version).to be < "2.0.0-135-g01789abdf"
+  end
+
+  specify "#runtime_dependencies" do
+    tab = described_class.new
+    expect(tab.runtime_dependencies).to be nil
+
+    tab.homebrew_version = "1.1.6"
+    expect(tab.runtime_dependencies).to be nil
+
+    tab.runtime_dependencies = []
+    expect(tab.runtime_dependencies).not_to be nil
+
+    tab.homebrew_version = "1.1.5"
+    expect(tab.runtime_dependencies).to be nil
+
+    tab.homebrew_version = "1.1.7"
+    expect(tab.runtime_dependencies).not_to be nil
+
+    tab.homebrew_version = "1.1.10"
+    expect(tab.runtime_dependencies).not_to be nil
+
+    tab.runtime_dependencies = [{ "full_name" => "foo", "version" => "1.0" }]
+    expect(tab.runtime_dependencies).not_to be nil
+  end
+
+  specify "#cxxstdlib" do
+    expect(subject.cxxstdlib.compiler).to eq(:clang)
+    expect(subject.cxxstdlib.type).to eq(:libcxx)
+  end
+
+  specify "other attributes" do
+    expect(subject.HEAD).to eq(TEST_SHA1)
+    expect(subject.tap.name).to eq("homebrew/core")
+    expect(subject.time).to eq(time)
+    expect(subject).not_to be_built_as_bottle
+    expect(subject).to be_poured_from_bottle
+  end
+
+  describe "::from_file" do
+    it "parses a Tab from a file" do
+      path = Pathname.new("#{TEST_FIXTURE_DIR}/receipt.json")
+      tab = described_class.from_file(path)
+      source_path = "/usr/local/Library/Taps/homebrew/homebrew-core/Formula/foo.rb"
+      runtime_dependencies = [{ "full_name" => "foo", "version" => "1.0" }]
+      changed_files = %w[INSTALL_RECEIPT.json bin/foo]
+
+      expect(tab.used_options.sort).to eq(used_options.sort)
+      expect(tab.unused_options.sort).to eq(unused_options.sort)
+      expect(tab.changed_files).to eq(changed_files)
+      expect(tab).not_to be_built_as_bottle
+      expect(tab).to be_poured_from_bottle
+      expect(tab).to be_stable
+      expect(tab).not_to be_devel
+      expect(tab).not_to be_head
+      expect(tab.tap.name).to eq("homebrew/core")
+      expect(tab.spec).to eq(:stable)
+      expect(tab.time).to eq(Time.at(1_403_827_774).to_i)
+      expect(tab.HEAD).to eq(TEST_SHA1)
+      expect(tab.cxxstdlib.compiler).to eq(:clang)
+      expect(tab.cxxstdlib.type).to eq(:libcxx)
+      expect(tab.runtime_dependencies).to eq(runtime_dependencies)
+      expect(tab.stable_version.to_s).to eq("2.14")
+      expect(tab.devel_version.to_s).to eq("2.15")
+      expect(tab.head_version.to_s).to eq("HEAD-0000000")
+      expect(tab.source["path"]).to eq(source_path)
+    end
+
+    it "can parse an old Tab file" do
+      path = Pathname.new("#{TEST_FIXTURE_DIR}/receipt_old.json")
+      tab = described_class.from_file(path)
+
+      expect(tab.used_options.sort).to eq(used_options.sort)
+      expect(tab.unused_options.sort).to eq(unused_options.sort)
+      expect(tab).not_to be_built_as_bottle
+      expect(tab).to be_poured_from_bottle
+      expect(tab).to be_stable
+      expect(tab).not_to be_devel
+      expect(tab).not_to be_head
+      expect(tab.tap.name).to eq("homebrew/core")
+      expect(tab.spec).to eq(:stable)
+      expect(tab.time).to eq(Time.at(1_403_827_774).to_i)
+      expect(tab.HEAD).to eq(TEST_SHA1)
+      expect(tab.cxxstdlib.compiler).to eq(:clang)
+      expect(tab.cxxstdlib.type).to eq(:libcxx)
+      expect(tab.runtime_dependencies).to be nil
+    end
+  end
+
+  describe "::create" do
+    it "creates a Tab" do
+      f = formula do
+        url "foo-1.0"
+        depends_on "bar"
+        depends_on "user/repo/from_tap"
+        depends_on "baz" => :build
+      end
+
+      tap = Tap.new("user", "repo")
+      from_tap = formula("from_tap", path: tap.path/"Formula/from_tap.rb") do
+        url "from_tap-1.0"
+      end
+      stub_formula_loader from_tap
+
+      stub_formula_loader formula("bar") { url "bar-2.0" }
+      stub_formula_loader formula("baz") { url "baz-3.0" }
+
+      compiler = DevelopmentTools.default_compiler
+      stdlib = :libcxx
+      tab = described_class.create(f, compiler, stdlib)
+
+      runtime_dependencies = [
+        { "full_name" => "bar", "version" => "2.0" },
+        { "full_name" => "user/repo/from_tap", "version" => "1.0" },
+      ]
+
+      expect(tab.runtime_dependencies).to eq(runtime_dependencies)
+      expect(tab.source["path"]).to eq(f.path.to_s)
+    end
+
+    it "can create a Tab from an alias" do
+      alias_path = CoreTap.instance.alias_dir/"bar"
+      f = formula(alias_path: alias_path) { url "foo-1.0" }
+      compiler = DevelopmentTools.default_compiler
+      stdlib = :libcxx
+      tab = described_class.create(f, compiler, stdlib)
+
+      expect(tab.source["path"]).to eq(f.alias_path.to_s)
+    end
+  end
+
+  describe "::for_keg" do
+    subject { described_class.for_keg(f.prefix) }
+
+    it "creates a Tab for a given Keg" do
+      f.prefix.mkpath
+      f_tab_path.write f_tab_content
+
+      expect(subject.tabfile).to eq(f_tab_path)
+    end
+
+    it "can create a Tab for a non-existant Keg" do
+      f.prefix.mkpath
+
+      expect(subject.tabfile).to be nil
+    end
+  end
+
+  describe "::for_formula" do
+    it "creates a Tab for a given Formula" do
+      tab = described_class.for_formula(f)
+      expect(tab.source["path"]).to eq(f.path.to_s)
+    end
+
+    it "can create a Tab for for a Formula from an alias" do
+      alias_path = CoreTap.instance.alias_dir/"bar"
+      f = formula(alias_path: alias_path) { url "foo-1.0" }
+
+      tab = described_class.for_formula(f)
+      expect(tab.source["path"]).to eq(alias_path.to_s)
+    end
+
+    it "creates a Tab for a given Formula" do
+      f.prefix.mkpath
+      f_tab_path.write f_tab_content
+
+      tab = described_class.for_formula(f)
+      expect(tab.tabfile).to eq(f_tab_path)
+    end
+
+    it "can create a Tab for a non-existant Formula" do
+      f.prefix.mkpath
+
+      tab = described_class.for_formula(f)
+      expect(tab.tabfile).to be nil
+    end
+
+    it "can create a Tab for a Formula with multiple Kegs" do
+      f.prefix.mkpath
+      f_tab_path.write f_tab_content
+
+      f2 = formula { url "foo-2.0" }
+      f2.prefix.mkpath
+
+      expect(f2.rack).to eq(f.rack)
+      expect(f.installed_prefixes.length).to eq(2)
+
+      tab = described_class.for_formula(f)
+      expect(tab.tabfile).to eq(f_tab_path)
+    end
+
+    it "can create a Tab for a Formula with an outdated Kegs" do
+      f_tab_path.write f_tab_content
+
+      f2 = formula { url "foo-2.0" }
+
+      expect(f2.rack).to eq(f.rack)
+      expect(f.installed_prefixes.length).to eq(1)
+
+      tab = described_class.for_formula(f)
+      expect(tab.tabfile).to eq(f_tab_path)
+    end
+  end
+
+  specify "#to_json" do
+    tab = described_class.new(JSON.parse(subject.to_json))
+    expect(tab.used_options.sort).to eq(subject.used_options.sort)
+    expect(tab.unused_options.sort).to eq(subject.unused_options.sort)
+    expect(tab.built_as_bottle).to eq(subject.built_as_bottle)
+    expect(tab.poured_from_bottle).to eq(subject.poured_from_bottle)
+    expect(tab.changed_files).to eq(subject.changed_files)
+    expect(tab.tap).to eq(subject.tap)
+    expect(tab.spec).to eq(subject.spec)
+    expect(tab.time).to eq(subject.time)
+    expect(tab.HEAD).to eq(subject.HEAD)
+    expect(tab.compiler).to eq(subject.compiler)
+    expect(tab.stdlib).to eq(subject.stdlib)
+    expect(tab.runtime_dependencies).to eq(subject.runtime_dependencies)
+    expect(tab.stable_version).to eq(subject.stable_version)
+    expect(tab.devel_version).to eq(subject.devel_version)
+    expect(tab.head_version).to eq(subject.head_version)
+    expect(tab.source["path"]).to eq(subject.source["path"])
+  end
+
+  specify "::remap_deprecated_options" do
+    deprecated_options = [DeprecatedOption.new("with-foo", "with-foo-new")]
+    remapped_options = described_class.remap_deprecated_options(deprecated_options, subject.used_options)
+    expect(remapped_options).to include(Option.new("without-bar"))
+    expect(remapped_options).to include(Option.new("with-foo-new"))
+  end
+end
diff --git a/Library/Homebrew/test/tab_test.rb b/Library/Homebrew/test/tab_test.rb
deleted file mode 100644
index f9824ba2a..000000000
--- a/Library/Homebrew/test/tab_test.rb
+++ /dev/null
@@ -1,315 +0,0 @@
-require "testing_env"
-require "tab"
-require "formula"
-
-class TabTests < Homebrew::TestCase
-  def setup
-    @used = Options.create(%w[--with-foo --without-bar])
-    @unused = Options.create(%w[--with-baz --without-qux])
-
-    @tab = Tab.new("used_options"         => @used.as_flags,
-                   "unused_options"       => @unused.as_flags,
-                   "built_as_bottle"      => false,
-                   "poured_from_bottle"   => true,
-                   "changed_files"        => [],
-                   "time"                 => nil,
-                   "source_modified_time" => 0,
-                   "HEAD"                 => TEST_SHA1,
-                   "compiler"             => "clang",
-                   "stdlib"               => "libcxx",
-                   "runtime_dependencies" => [],
-                   "source"               => {
-                     "tap" => "homebrew/core",
-                     "path" => nil,
-                     "spec" => "stable",
-                     "versions" => {
-                       "stable" => "0.10",
-                       "devel" => "0.14",
-                       "head" => "HEAD-1111111",
-                     },
-                   })
-  end
-
-  def test_defaults
-    tab = Tab.empty
-
-    assert_equal HOMEBREW_VERSION, tab.homebrew_version
-    assert_empty tab.unused_options
-    assert_empty tab.used_options
-    assert_nil tab.changed_files
-    refute_predicate tab, :built_as_bottle
-    refute_predicate tab, :poured_from_bottle
-    assert_predicate tab, :stable?
-    refute_predicate tab, :devel?
-    refute_predicate tab, :head?
-    assert_nil tab.tap
-    assert_nil tab.time
-    assert_nil tab.HEAD
-    assert_empty tab.runtime_dependencies
-    assert_nil tab.stable_version
-    assert_nil tab.devel_version
-    assert_nil tab.head_version
-    assert_equal DevelopmentTools.default_compiler, tab.cxxstdlib.compiler
-    assert_nil tab.cxxstdlib.type
-    assert_nil tab.source["path"]
-  end
-
-  def test_include?
-    assert_includes @tab, "with-foo"
-    assert_includes @tab, "without-bar"
-  end
-
-  def test_with?
-    assert @tab.with?("foo")
-    assert @tab.with?("qux")
-    refute @tab.with?("bar")
-    refute @tab.with?("baz")
-  end
-
-  def test_universal?
-    tab = Tab.new(used_options: %w[--universal])
-    assert_predicate tab, :universal?
-  end
-
-  def test_parsed_homebrew_version
-    tab = Tab.new
-    assert_same Version::NULL, tab.parsed_homebrew_version
-
-    tab = Tab.new(homebrew_version: "1.2.3")
-    assert_equal "1.2.3", tab.parsed_homebrew_version
-    assert tab.parsed_homebrew_version < "1.2.3-1-g12789abdf"
-    assert_kind_of Version, tab.parsed_homebrew_version
-
-    tab.homebrew_version = "1.2.4-567-g12789abdf"
-    assert tab.parsed_homebrew_version > "1.2.4"
-    assert tab.parsed_homebrew_version > "1.2.4-566-g21789abdf"
-    assert tab.parsed_homebrew_version < "1.2.4-568-g01789abdf"
-
-    tab = Tab.new(homebrew_version: "2.0.0-134-gabcdefabc-dirty")
-    assert tab.parsed_homebrew_version > "2.0.0"
-    assert tab.parsed_homebrew_version > "2.0.0-133-g21789abdf"
-    assert tab.parsed_homebrew_version < "2.0.0-135-g01789abdf"
-  end
-
-  def test_runtime_dependencies
-    tab = Tab.new
-    assert_nil tab.runtime_dependencies
-
-    tab.homebrew_version = "1.1.6"
-    assert_nil tab.runtime_dependencies
-
-    tab.runtime_dependencies = []
-    refute_nil tab.runtime_dependencies
-
-    tab.homebrew_version = "1.1.5"
-    assert_nil tab.runtime_dependencies
-
-    tab.homebrew_version = "1.1.7"
-    refute_nil tab.runtime_dependencies
-
-    tab.homebrew_version = "1.1.10"
-    refute_nil tab.runtime_dependencies
-
-    tab.runtime_dependencies = [{ "full_name" => "foo", "version" => "1.0" }]
-    refute_nil tab.runtime_dependencies
-  end
-
-  def test_cxxstdlib
-    assert_equal :clang, @tab.cxxstdlib.compiler
-    assert_equal :libcxx, @tab.cxxstdlib.type
-  end
-
-  def test_other_attributes
-    assert_equal TEST_SHA1, @tab.HEAD
-    assert_equal "homebrew/core", @tab.tap.name
-    assert_nil @tab.time
-    refute_predicate @tab, :built_as_bottle
-    assert_predicate @tab, :poured_from_bottle
-  end
-
-  def test_from_old_version_file
-    path = Pathname.new("#{TEST_FIXTURE_DIR}/receipt_old.json")
-    tab = Tab.from_file(path)
-
-    assert_equal @used.sort, tab.used_options.sort
-    assert_equal @unused.sort, tab.unused_options.sort
-    refute_predicate tab, :built_as_bottle
-    assert_predicate tab, :poured_from_bottle
-    assert_predicate tab, :stable?
-    refute_predicate tab, :devel?
-    refute_predicate tab, :head?
-    assert_equal "homebrew/core", tab.tap.name
-    assert_equal :stable, tab.spec
-    refute_nil tab.time
-    assert_equal TEST_SHA1, tab.HEAD
-    assert_equal :clang, tab.cxxstdlib.compiler
-    assert_equal :libcxx, tab.cxxstdlib.type
-    assert_nil tab.runtime_dependencies
-  end
-
-  def test_from_file
-    path = Pathname.new("#{TEST_FIXTURE_DIR}/receipt.json")
-    tab = Tab.from_file(path)
-    source_path = "/usr/local/Library/Taps/homebrew/homebrew-core/Formula/foo.rb"
-    runtime_dependencies = [{ "full_name" => "foo", "version" => "1.0" }]
-    changed_files = %w[INSTALL_RECEIPT.json bin/foo]
-
-    assert_equal @used.sort, tab.used_options.sort
-    assert_equal @unused.sort, tab.unused_options.sort
-    assert_equal changed_files, tab.changed_files
-    refute_predicate tab, :built_as_bottle
-    assert_predicate tab, :poured_from_bottle
-    assert_predicate tab, :stable?
-    refute_predicate tab, :devel?
-    refute_predicate tab, :head?
-    assert_equal "homebrew/core", tab.tap.name
-    assert_equal :stable, tab.spec
-    refute_nil tab.time
-    assert_equal TEST_SHA1, tab.HEAD
-    assert_equal :clang, tab.cxxstdlib.compiler
-    assert_equal :libcxx, tab.cxxstdlib.type
-    assert_equal runtime_dependencies, tab.runtime_dependencies
-    assert_equal "2.14", tab.stable_version.to_s
-    assert_equal "2.15", tab.devel_version.to_s
-    assert_equal "HEAD-0000000", tab.head_version.to_s
-    assert_equal source_path, tab.source["path"]
-  end
-
-  def test_create
-    f = formula do
-      url "foo-1.0"
-      depends_on "bar"
-      depends_on "user/repo/from_tap"
-      depends_on "baz" => :build
-    end
-
-    tap = Tap.new("user", "repo")
-    from_tap = formula("from_tap", tap.path/"Formula/from_tap.rb") do
-      url "from_tap-1.0"
-    end
-    stub_formula_loader from_tap
-
-    stub_formula_loader formula("bar") { url "bar-2.0" }
-    stub_formula_loader formula("baz") { url "baz-3.0" }
-
-    compiler = DevelopmentTools.default_compiler
-    stdlib = :libcxx
-    tab = Tab.create(f, compiler, stdlib)
-
-    runtime_dependencies = [
-      { "full_name" => "bar", "version" => "2.0" },
-      { "full_name" => "user/repo/from_tap", "version" => "1.0" },
-    ]
-
-    assert_equal runtime_dependencies, tab.runtime_dependencies
-    assert_equal f.path.to_s, tab.source["path"]
-  end
-
-  def test_create_from_alias
-    alias_path = CoreTap.instance.alias_dir/"bar"
-    f = formula(alias_path: alias_path) { url "foo-1.0" }
-    compiler = DevelopmentTools.default_compiler
-    stdlib = :libcxx
-    tab = Tab.create(f, compiler, stdlib)
-
-    assert_equal f.alias_path.to_s, tab.source["path"]
-  end
-
-  def test_for_formula
-    f = formula { url "foo-1.0" }
-    tab = Tab.for_formula(f)
-
-    assert_equal f.path.to_s, tab.source["path"]
-  end
-
-  def test_for_formula_from_alias
-    alias_path = CoreTap.instance.alias_dir/"bar"
-    f = formula(alias_path: alias_path) { url "foo-1.0" }
-    tab = Tab.for_formula(f)
-
-    assert_equal alias_path.to_s, tab.source["path"]
-  end
-
-  def test_to_json
-    tab = Tab.new(JSON.parse(@tab.to_json))
-    assert_equal @tab.used_options.sort, tab.used_options.sort
-    assert_equal @tab.unused_options.sort, tab.unused_options.sort
-    assert_equal @tab.built_as_bottle, tab.built_as_bottle
-    assert_equal @tab.poured_from_bottle, tab.poured_from_bottle
-    assert_equal @tab.changed_files, tab.changed_files
-    assert_equal @tab.tap, tab.tap
-    assert_equal @tab.spec, tab.spec
-    assert_equal @tab.time, tab.time
-    assert_equal @tab.HEAD, tab.HEAD
-    assert_equal @tab.compiler, tab.compiler
-    assert_equal @tab.stdlib, tab.stdlib
-    assert_equal @tab.runtime_dependencies, tab.runtime_dependencies
-    assert_equal @tab.stable_version, tab.stable_version
-    assert_equal @tab.devel_version, tab.devel_version
-    assert_equal @tab.head_version, tab.head_version
-    assert_equal @tab.source["path"], tab.source["path"]
-  end
-
-  def test_remap_deprecated_options
-    deprecated_options = [DeprecatedOption.new("with-foo", "with-foo-new")]
-    remapped_options = Tab.remap_deprecated_options(deprecated_options, @tab.used_options)
-    assert_includes remapped_options, Option.new("without-bar")
-    assert_includes remapped_options, Option.new("with-foo-new")
-  end
-end
-
-class TabLoadingTests < Homebrew::TestCase
-  def setup
-    @f = formula { url "foo-1.0" }
-    @f.prefix.mkpath
-    @path = @f.prefix.join(Tab::FILENAME)
-    @path.write TEST_FIXTURE_DIR.join("receipt.json").read
-  end
-
-  def teardown
-    @f.rack.rmtree
-  end
-
-  def test_for_keg
-    tab = Tab.for_keg(@f.prefix)
-    assert_equal @path, tab.tabfile
-  end
-
-  def test_for_keg_nonexistent_path
-    @path.unlink
-    tab = Tab.for_keg(@f.prefix)
-    assert_nil tab.tabfile
-  end
-
-  def test_for_formula
-    tab = Tab.for_formula(@f)
-    assert_equal @path, tab.tabfile
-  end
-
-  def test_for_formula_nonexistent_path
-    @path.unlink
-    tab = Tab.for_formula(@f)
-    assert_nil tab.tabfile
-  end
-
-  def test_for_formula_multiple_kegs
-    f2 = formula { url "foo-2.0" }
-    f2.prefix.mkpath
-
-    assert_equal @f.rack, f2.rack
-    assert_equal 2, @f.installed_prefixes.length
-
-    tab = Tab.for_formula(@f)
-    assert_equal @path, tab.tabfile
-  end
-
-  def test_for_formula_outdated_keg
-    f2 = formula { url "foo-2.0" }
-
-    assert_equal @f.rack, f2.rack
-    assert_equal 1, @f.installed_prefixes.length
-
-    tab = Tab.for_formula(f2)
-    assert_equal @path, tab.tabfile
-  end
-end
diff --git a/Library/Homebrew/test/tap_new_test.rb b/Library/Homebrew/test/tap_new_test.rb
deleted file mode 100644
index 261a334f0..000000000
--- a/Library/Homebrew/test/tap_new_test.rb
+++ /dev/null
@@ -1,9 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestTapNew < IntegrationCommandTestCase
-  def test_tap_readme
-    assert_equal "", cmd("tap-new", "homebrew/foo", "--verbose")
-    readme = HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-foo/README.md"
-    assert readme.exist?, "The README should be created"
-  end
-end
diff --git a/Library/Homebrew/test/tap_test.rb b/Library/Homebrew/test/tap_test.rb
index 7114cdf22..729fc8198 100644
--- a/Library/Homebrew/test/tap_test.rb
+++ b/Library/Homebrew/test/tap_test.rb
@@ -1,39 +1,10 @@
 require "testing_env"
-require "testing_env"
-
-class IntegrationCommandTestTap < IntegrationCommandTestCase
-  def test_tap
-    path = Tap::TAP_DIRECTORY/"homebrew/homebrew-foo"
-    path.mkpath
-    path.cd do
-      shutup do
-        system "git", "init"
-        system "git", "remote", "add", "origin", "https://github.com/Homebrew/homebrew-foo"
-        FileUtils.touch "readme"
-        system "git", "add", "--all"
-        system "git", "commit", "-m", "init"
-      end
-    end
-
-    assert_match "homebrew/foo", cmd("tap")
-    assert_match "homebrew/science", cmd("tap", "--list-official")
-    assert_match "2 taps", cmd("tap-info")
-    assert_match "https://github.com/Homebrew/homebrew-foo", cmd("tap-info", "homebrew/foo")
-    assert_match "https://github.com/Homebrew/homebrew-foo", cmd("tap-info", "--json=v1", "--installed")
-    assert_match "Pinned homebrew/foo", cmd("tap-pin", "homebrew/foo")
-    assert_match "homebrew/foo", cmd("tap", "--list-pinned")
-    assert_match "Unpinned homebrew/foo", cmd("tap-unpin", "homebrew/foo")
-    assert_match "Tapped", cmd("tap", "homebrew/bar", path/".git")
-    assert_match "Untapped", cmd("untap", "homebrew/bar")
-    assert_equal "", cmd("tap", "homebrew/bar", path/".git", "-q", "--full")
-    assert_match "Untapped", cmd("untap", "homebrew/bar")
-  end
-end
 
 class TapTest < Homebrew::TestCase
   include FileUtils
 
   def setup
+    super
     @path = Tap::TAP_DIRECTORY/"homebrew/homebrew-foo"
     @path.mkpath
     @tap = Tap.new("Homebrew", "foo")
@@ -65,13 +36,6 @@ class TapTest < Homebrew::TestCase
   end
 
   def setup_git_repo
-    env = ENV.to_hash
-    %w[AUTHOR COMMITTER].each do |role|
-      ENV["GIT_#{role}_NAME"] = "brew tests"
-      ENV["GIT_#{role}_EMAIL"] = "brew-tests@localhost"
-      ENV["GIT_#{role}_DATE"] = "Thu May 21 00:04:11 2009 +0100"
-    end
-
     @path.cd do
       shutup do
         system "git", "init"
@@ -80,12 +44,6 @@ class TapTest < Homebrew::TestCase
         system "git", "commit", "-m", "init"
       end
     end
-  ensure
-    ENV.replace(env)
-  end
-
-  def teardown
-    @path.rmtree
   end
 
   def test_fetch
@@ -171,8 +129,6 @@ class TapTest < Homebrew::TestCase
       end
     end
     refute_predicate services_tap, :private?
-  ensure
-    services_tap.path.rmtree if services_tap
   end
 
   def test_remote_not_git_repo
@@ -189,10 +145,10 @@ class TapTest < Homebrew::TestCase
     touch @path/"README"
     setup_git_repo
 
-    assert_equal "e1893a6bd191ba895c71b652ff8376a6114c7fa7", @tap.git_head
-    assert_equal "e189", @tap.git_short_head
-    assert_match "years ago", @tap.git_last_commit
-    assert_equal "2009-05-21", @tap.git_last_commit_date
+    assert_equal "0453e16c8e3fac73104da50927a86221ca0740c2", @tap.git_head
+    assert_equal "0453", @tap.git_short_head
+    assert_match(/\A\d+ .+ ago\Z/, @tap.git_last_commit)
+    assert_equal "2017-01-22", @tap.git_last_commit_date
   end
 
   def test_private_remote
@@ -256,8 +212,6 @@ class TapTest < Homebrew::TestCase
     refute_predicate tap, :installed?
     refute_predicate HOMEBREW_PREFIX/"share/man/man1/brew-tap-cmd.1", :exist?
     refute_predicate HOMEBREW_PREFIX/"share/man/man1", :exist?
-  ensure
-    (HOMEBREW_PREFIX/"share").rmtree if (HOMEBREW_PREFIX/"share").exist?
   end
 
   def test_pin_and_unpin
@@ -285,6 +239,7 @@ class CoreTapTest < Homebrew::TestCase
   include FileUtils
 
   def setup
+    super
     @repo = CoreTap.new
   end
 
@@ -322,8 +277,5 @@ class CoreTapTest < Homebrew::TestCase
     assert_equal ["bar"], @repo.aliases
     assert_equal @repo.alias_table, "bar" => "foo"
     assert_equal @repo.alias_reverse_table, "foo" => ["bar"]
-  ensure
-    @formula_file.unlink
-    @repo.alias_dir.rmtree
   end
 end
diff --git a/Library/Homebrew/test/test_formula_test.rb b/Library/Homebrew/test/test_formula_test.rb
deleted file mode 100644
index 5ad2db9e9..000000000
--- a/Library/Homebrew/test/test_formula_test.rb
+++ /dev/null
@@ -1,30 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestTestFormula < IntegrationCommandTestCase
-  def test_test_formula
-    assert_match "This command requires a formula argument", cmd_fail("test")
-    assert_match "Testing requires the latest version of testball",
-      cmd_fail("test", testball)
-
-    cmd("install", testball)
-    assert_match "testball defines no test", cmd_fail("test", testball)
-
-    setup_test_formula "testball_copy", <<-EOS.undent
-      head "https://github.com/example/testball2.git"
-
-      devel do
-        url "file://#{TEST_FIXTURE_DIR}/tarballs/testball-0.1.tbz"
-        sha256 "#{TESTBALL_SHA256}"
-      end
-
-      keg_only "just because"
-
-      test do
-      end
-    EOS
-
-    cmd("install", "testball_copy")
-    assert_match "Testing testball_copy", cmd("test", "--HEAD", "testball_copy")
-    assert_match "Testing testball_copy", cmd("test", "--devel", "testball_copy")
-  end
-end
diff --git a/Library/Homebrew/test/testing_env.rb b/Library/Homebrew/test/testing_env.rb
index e2ba2e4e4..999fa1013 100644
--- a/Library/Homebrew/test/testing_env.rb
+++ b/Library/Homebrew/test/testing_env.rb
@@ -1,21 +1,18 @@
-$:.unshift File.expand_path("../..", __FILE__)
-$:.unshift File.expand_path("../support/lib", __FILE__)
-
-require "simplecov" if ENV["HOMEBREW_TESTS_COVERAGE"]
-require "global"
-require "formulary"
-
-# Test environment setup
-(HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-core/Formula").mkpath
-%w[cache formula_cache locks cellar logs temp].each { |d| HOMEBREW_PREFIX.parent.join(d).mkpath }
-
 begin
   require "minitest/autorun"
-  require "parallel_tests/test/runtime_logger"
+  require "minitest/reporters"
+  Minitest::Reporters.use! Minitest::Reporters::DefaultReporter.new(color: true)
   require "mocha/setup"
+  require "parallel_tests/test/runtime_logger"
+  require "simplecov" if ENV["HOMEBREW_TESTS_COVERAGE"]
 rescue LoadError
-  abort "Run `bundle install` or install the mocha and minitest gems before running the tests"
+  abort "Run `bundle install` before running the tests."
 end
 
+$LOAD_PATH.unshift(File.expand_path("#{ENV["HOMEBREW_LIBRARY"]}/Homebrew"))
+$LOAD_PATH.unshift(File.expand_path("#{ENV["HOMEBREW_LIBRARY"]}/Homebrew/test/support/lib"))
+
+require "global"
+
 require "test/support/helper/test_case"
 require "test/support/helper/integration_command_test_case"
diff --git a/Library/Homebrew/test/uninstall_test.rb b/Library/Homebrew/test/uninstall_test.rb
index 597e77e40..a9230ffac 100644
--- a/Library/Homebrew/test/uninstall_test.rb
+++ b/Library/Homebrew/test/uninstall_test.rb
@@ -3,6 +3,8 @@ require "cmd/uninstall"
 
 class UninstallTests < Homebrew::TestCase
   def setup
+    super
+
     @dependency = formula("dependency") { url "f-1" }
     @dependent = formula("dependent") do
       url "f-1"
@@ -28,10 +30,7 @@ class UninstallTests < Homebrew::TestCase
 
   def teardown
     Homebrew.failed = false
-    [@dependency, @dependent].each do |f|
-      f.installed_kegs.each(&:remove_opt_record)
-      f.rack.rmtree
-    end
+    super
   end
 
   def handle_unsatisfied_dependents
@@ -59,14 +58,5 @@ class UninstallTests < Homebrew::TestCase
       assert_empty handle_unsatisfied_dependents
       refute_predicate Homebrew, :failed?
     end
-  ensure
-    ARGV.delete("--ignore-dependencies")
-  end
-end
-
-class IntegrationCommandTestUninstall < IntegrationCommandTestCase
-  def test_uninstall
-    cmd("install", testball)
-    assert_match "Uninstalling testball", cmd("uninstall", "--force", testball)
   end
 end
diff --git a/Library/Homebrew/test/unlink_test.rb b/Library/Homebrew/test/unlink_test.rb
deleted file mode 100644
index 6d5cefc67..000000000
--- a/Library/Homebrew/test/unlink_test.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestUnlink < IntegrationCommandTestCase
-  def test_unlink
-    setup_test_formula "testball"
-
-    cmd("install", "testball")
-    assert_match "Would remove", cmd("unlink", "--dry-run", "testball")
-  end
-end
diff --git a/Library/Homebrew/test/unlinkapps_test.rb b/Library/Homebrew/test/unlinkapps_test.rb
deleted file mode 100644
index 9d9672199..000000000
--- a/Library/Homebrew/test/unlinkapps_test.rb
+++ /dev/null
@@ -1,19 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestUnlinkapps < IntegrationCommandTestCase
-  def test_unlinkapps
-    home_dir = Pathname.new(mktmpdir)
-    apps_dir = home_dir/"Applications"
-    apps_dir.mkpath
-
-    setup_test_formula "testball"
-
-    source_app = (HOMEBREW_CELLAR/"testball/0.1/TestBall.app")
-    source_app.mkpath
-
-    FileUtils.ln_s source_app, "#{apps_dir}/TestBall.app"
-
-    assert_match "Unlinking: #{apps_dir}/TestBall.app",
-      cmd("unlinkapps", "--local", "HOME" => home_dir)
-  end
-end
diff --git a/Library/Homebrew/test/unpack_test.rb b/Library/Homebrew/test/unpack_test.rb
deleted file mode 100644
index bbff6ad1c..000000000
--- a/Library/Homebrew/test/unpack_test.rb
+++ /dev/null
@@ -1,13 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestUnpack < IntegrationCommandTestCase
-  def test_unpack
-    setup_test_formula "testball"
-
-    mktmpdir do |path|
-      cmd "unpack", "testball", "--destdir=#{path}"
-      assert File.directory?("#{path}/testball-0.1"),
-        "The tarball should be unpacked"
-    end
-  end
-end
diff --git a/Library/Homebrew/test/update_report_test.rb b/Library/Homebrew/test/update_report_test.rb
deleted file mode 100644
index 6b6cec6ce..000000000
--- a/Library/Homebrew/test/update_report_test.rb
+++ /dev/null
@@ -1,134 +0,0 @@
-require "testing_env"
-require "cmd/update-report"
-require "formula_versions"
-require "yaml"
-
-class ReportTests < Homebrew::TestCase
-  class ReporterMock < ::Reporter
-    attr_accessor :diff
-
-    def initialize(tap)
-      @tap = tap
-      ENV["HOMEBREW_UPDATE_BEFORE#{repo_var}"] = "12345678"
-      ENV["HOMEBREW_UPDATE_AFTER#{repo_var}"] = "abcdef12"
-      super(tap)
-    end
-  end
-
-  def fixture(name)
-    self.class.fixture_data[name] || ""
-  end
-
-  def self.fixture_data
-    @fixture_data ||= YAML.load_file("#{TEST_FIXTURE_DIR}/updater_fixture.yaml")
-  end
-
-  def setup
-    @tap = CoreTap.new
-    @reporter = ReporterMock.new(@tap)
-    @hub = ReporterHub.new
-  end
-
-  def perform_update(fixture_name = "")
-    Formulary.stubs(:factory).returns(stub(pkg_version: "1.0"))
-    FormulaVersions.stubs(:new).returns(stub(formula_at_revision: "2.0"))
-    @reporter.diff = fixture(fixture_name)
-    @hub.add(@reporter) if @reporter.updated?
-  end
-
-  def test_update_report_without_revision_var
-    ENV.delete_if { |k, _v| k.start_with? "HOMEBREW_UPDATE" }
-    assert_raises(Reporter::ReporterRevisionUnsetError) { Reporter.new(@tap) }
-  end
-
-  def test_update_homebrew_without_any_changes
-    perform_update
-    assert_empty @hub
-  end
-
-  def test_update_homebrew_without_formulae_changes
-    perform_update("update_git_diff_output_without_formulae_changes")
-    assert_empty @hub.select_formula(:M)
-    assert_empty @hub.select_formula(:A)
-    assert_empty @hub.select_formula(:D)
-  end
-
-  def test_update_homebrew_with_formulae_changes
-    perform_update("update_git_diff_output_with_formulae_changes")
-    assert_equal %w[xar yajl], @hub.select_formula(:M)
-    assert_equal %w[antiword bash-completion ddrescue dict lua], @hub.select_formula(:A)
-  end
-
-  def test_update_homebrew_with_removed_formulae
-    perform_update("update_git_diff_output_with_removed_formulae")
-    assert_equal %w[libgsasl], @hub.select_formula(:D)
-  end
-
-  def test_update_homebrew_with_changed_filetype
-    perform_update("update_git_diff_output_with_changed_filetype")
-    assert_equal %w[elixir], @hub.select_formula(:M)
-    assert_equal %w[libbson], @hub.select_formula(:A)
-    assert_equal %w[libgsasl], @hub.select_formula(:D)
-  end
-
-  def test_update_homebrew_with_formula_rename
-    @tap.stubs(:formula_renames).returns("cv" => "progress")
-    perform_update("update_git_diff_output_with_formula_rename")
-    assert_empty @hub.select_formula(:A)
-    assert_empty @hub.select_formula(:D)
-    assert_equal [["cv", "progress"]], @hub.select_formula(:R)
-  end
-
-  def test_update_homebrew_with_restructured_tap
-    tap = Tap.new("foo", "bar")
-    @reporter = ReporterMock.new(tap)
-    tap.path.join("Formula").mkpath
-
-    perform_update("update_git_diff_output_with_restructured_tap")
-    assert_empty @hub.select_formula(:A)
-    assert_empty @hub.select_formula(:D)
-    assert_empty @hub.select_formula(:R)
-  ensure
-    tap.path.parent.rmtree
-  end
-
-  def test_update_homebrew_with_formula_rename_and_restructuring
-    tap = Tap.new("foo", "bar")
-    @reporter = ReporterMock.new(tap)
-    tap.path.join("Formula").mkpath
-    tap.stubs(:formula_renames).returns("xchat" => "xchat2")
-
-    perform_update("update_git_diff_output_with_formula_rename_and_restructuring")
-    assert_empty @hub.select_formula(:A)
-    assert_empty @hub.select_formula(:D)
-    assert_equal [%w[foo/bar/xchat foo/bar/xchat2]], @hub.select_formula(:R)
-  ensure
-    tap.path.parent.rmtree
-  end
-
-  def test_update_homebrew_simulate_homebrew_php_restructuring
-    tap = Tap.new("foo", "bar")
-    @reporter = ReporterMock.new(tap)
-    tap.path.join("Formula").mkpath
-
-    perform_update("update_git_diff_simulate_homebrew_php_restructuring")
-    assert_empty @hub.select_formula(:A)
-    assert_empty @hub.select_formula(:D)
-    assert_empty @hub.select_formula(:R)
-  ensure
-    tap.path.parent.rmtree
-  end
-
-  def test_update_homebrew_with_tap_formulae_changes
-    tap = Tap.new("foo", "bar")
-    @reporter = ReporterMock.new(tap)
-    tap.path.join("Formula").mkpath
-
-    perform_update("update_git_diff_output_with_tap_formulae_changes")
-    assert_equal %w[foo/bar/lua], @hub.select_formula(:A)
-    assert_equal %w[foo/bar/git], @hub.select_formula(:M)
-    assert_empty @hub.select_formula(:D)
-  ensure
-    tap.path.parent.rmtree
-  end
-end
diff --git a/Library/Homebrew/test/upgrade_test.rb b/Library/Homebrew/test/upgrade_test.rb
deleted file mode 100644
index f3f5dccc7..000000000
--- a/Library/Homebrew/test/upgrade_test.rb
+++ /dev/null
@@ -1,12 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestUpgrade < IntegrationCommandTestCase
-  def test_upgrade
-    setup_test_formula "testball"
-    (HOMEBREW_CELLAR/"testball/0.0.1/foo").mkpath
-
-    cmd("upgrade")
-    assert((HOMEBREW_CELLAR/"testball/0.1").directory?,
-      "The latest version directory should be created")
-  end
-end
diff --git a/Library/Homebrew/test/uses_test.rb b/Library/Homebrew/test/uses_test.rb
deleted file mode 100644
index 1fad0da28..000000000
--- a/Library/Homebrew/test/uses_test.rb
+++ /dev/null
@@ -1,16 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestUses < IntegrationCommandTestCase
-  def test_uses
-    setup_test_formula "foo"
-    setup_test_formula "bar"
-    setup_test_formula "baz", <<-EOS.undent
-      url "https://example.com/baz-1.0"
-      depends_on "bar"
-    EOS
-
-    assert_equal "", cmd("uses", "baz")
-    assert_equal "baz", cmd("uses", "bar")
-    assert_match(/(bar\nbaz|baz\nbar)/, cmd("uses", "--recursive", "foo"))
-  end
-end
diff --git a/Library/Homebrew/test/utils/bottles/bintray_spec.rb b/Library/Homebrew/test/utils/bottles/bintray_spec.rb
new file mode 100644
index 000000000..a7dfc00ea
--- /dev/null
+++ b/Library/Homebrew/test/utils/bottles/bintray_spec.rb
@@ -0,0 +1,18 @@
+require "utils/bottles"
+
+describe Utils::Bottles::Bintray do
+  describe "::package" do
+    it "converts a Formula name to a package name" do
+      expect(described_class.package("openssl@1.1")).to eq("openssl:1.1")
+      expect(described_class.package("gtk+")).to eq("gtkx")
+      expect(described_class.package("llvm")).to eq("llvm")
+    end
+  end
+
+  describe "::repository" do
+    it "returns the repository for a given Tap" do
+      expect(described_class.repository(Tap.new("homebrew", "bintray-test")))
+        .to eq("bottles-bintray-test")
+    end
+  end
+end
diff --git a/Library/Homebrew/test/utils/bottles/bottles_spec.rb b/Library/Homebrew/test/utils/bottles/bottles_spec.rb
new file mode 100644
index 000000000..8b54b0b34
--- /dev/null
+++ b/Library/Homebrew/test/utils/bottles/bottles_spec.rb
@@ -0,0 +1,80 @@
+require "utils/bottles"
+
+describe Utils::Bottles do
+  describe "#tag", :needs_macos do
+    it "returns :tiger_foo on Tiger PowerPC" do
+      allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.4"))
+      allow(Hardware::CPU).to receive(:type).and_return(:ppc)
+      allow(Hardware::CPU).to receive(:family).and_return(:foo)
+      allow(MacOS).to receive(:prefer_64_bit?).and_return(false)
+      expect(described_class.tag).to eq(:tiger_foo)
+    end
+
+    it "returns :tiger on Tiger Intel" do
+      allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.4"))
+      allow(Hardware::CPU).to receive(:type).and_return(:intel)
+      allow(MacOS).to receive(:prefer_64_bit?).and_return(false)
+      expect(described_class.tag).to eq(:tiger)
+    end
+
+    it "returns :tiger_g5_64 on Tiger PowerPC 64-bit" do
+      allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.4"))
+      allow(Hardware::CPU).to receive(:type).and_return(:ppc)
+      allow(Hardware::CPU).to receive(:family).and_return(:g5)
+      allow(MacOS).to receive(:prefer_64_bit?).and_return(true)
+      expect(described_class.tag).to eq(:tiger_g5_64)
+    end
+
+    # Note that this will probably never be used
+    it "returns :tiger_64 on Tiger Intel 64-bit" do
+      allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.4"))
+      allow(Hardware::CPU).to receive(:type).and_return(:intel)
+      allow(MacOS).to receive(:prefer_64_bit?).and_return(true)
+      expect(described_class.tag).to eq(:tiger_64)
+    end
+
+    it "returns :leopard on Leopard Intel" do
+      allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.5"))
+      allow(Hardware::CPU).to receive(:type).and_return(:intel)
+      allow(MacOS).to receive(:prefer_64_bit?).and_return(false)
+      expect(described_class.tag).to eq(:leopard)
+    end
+
+    it "returns :leopard_g5_64 on Leopard PowerPC 64-bit" do
+      allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.5"))
+      allow(Hardware::CPU).to receive(:type).and_return(:ppc)
+      allow(Hardware::CPU).to receive(:family).and_return(:g5)
+      allow(MacOS).to receive(:prefer_64_bit?).and_return(true)
+      expect(described_class.tag).to eq(:leopard_g5_64)
+    end
+
+    it "returns :leopard_64 on Leopard Intel 64-bit" do
+      allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.5"))
+      allow(Hardware::CPU).to receive(:type).and_return(:intel)
+      allow(MacOS).to receive(:prefer_64_bit?).and_return(true)
+      expect(described_class.tag).to eq(:leopard_64)
+    end
+
+    it "returns :snow_leopard_32 on Snow Leopard 32-bit" do
+      allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.6"))
+      allow(Hardware::CPU).to receive(:is_64_bit?).and_return(false)
+      expect(described_class.tag).to eq(:snow_leopard_32)
+    end
+
+    it "returns :snow_leopard on Snow Leopard 64-bit" do
+      allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.6"))
+      allow(Hardware::CPU).to receive(:is_64_bit?).and_return(true)
+      expect(described_class.tag).to eq(:snow_leopard)
+    end
+
+    it "returns :lion on Lion" do
+      allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.7"))
+      expect(described_class.tag).to eq(:lion)
+    end
+
+    it "returns :mountain_lion on Mountain Lion" do
+      allow(MacOS).to receive(:version).and_return(MacOS::Version.new("10.8"))
+      expect(described_class.tag).to eq(:mountain_lion)
+    end
+  end
+end
diff --git a/Library/Homebrew/test/utils/bottles/collector_spec.rb b/Library/Homebrew/test/utils/bottles/collector_spec.rb
new file mode 100644
index 000000000..08484e545
--- /dev/null
+++ b/Library/Homebrew/test/utils/bottles/collector_spec.rb
@@ -0,0 +1,45 @@
+require "utils/bottles"
+
+describe Utils::Bottles::Collector do
+  describe "#fetch_checksum_for" do
+    it "returns passed tags" do
+      subject[:lion] = "foo"
+      subject[:mountain_lion] = "bar"
+      expect(subject.fetch_checksum_for(:mountain_lion)).to eq(["bar", :mountain_lion])
+    end
+
+    it "returns nil if empty" do
+      expect(subject.fetch_checksum_for(:foo)).to be nil
+    end
+
+    it "returns nil when there is no match" do
+      subject[:lion] = "foo"
+      expect(subject.fetch_checksum_for(:foo)).to be nil
+    end
+
+    it "returns nil when there is no match and later tag is present" do
+      subject[:lion_or_later] = "foo"
+      expect(subject.fetch_checksum_for(:foo)).to be nil
+    end
+
+    it "prefers exact matches" do
+      subject[:lion_or_later] = "foo"
+      subject[:mountain_lion] = "bar"
+      expect(subject.fetch_checksum_for(:mountain_lion)).to eq(["bar", :mountain_lion])
+    end
+
+    it "finds '_or_later' tags", :needs_macos do
+      subject[:lion_or_later] = "foo"
+      expect(subject.fetch_checksum_for(:mountain_lion)).to eq(["foo", :lion_or_later])
+      expect(subject.fetch_checksum_for(:snow_leopard)).to be nil
+    end
+
+    it "finds '_altivec' tags", :needs_macos do
+      subject[:tiger_altivec] = "foo"
+      expect(subject.fetch_checksum_for(:tiger_g4)).to eq(["foo", :tiger_altivec])
+      expect(subject.fetch_checksum_for(:tiger_g4e)).to eq(["foo", :tiger_altivec])
+      expect(subject.fetch_checksum_for(:tiger_g5)).to eq(["foo", :tiger_altivec])
+      expect(subject.fetch_checksum_for(:tiger_g3)).to be nil
+    end
+  end
+end
diff --git a/Library/Homebrew/test/utils/popen_spec.rb b/Library/Homebrew/test/utils/popen_spec.rb
new file mode 100644
index 000000000..e3704a876
--- /dev/null
+++ b/Library/Homebrew/test/utils/popen_spec.rb
@@ -0,0 +1,28 @@
+require "utils/popen"
+
+describe Utils do
+  describe "::popen_read" do
+    it "reads the standard output of a given command" do
+      expect(subject.popen_read("sh", "-c", "echo success").chomp).to eq("success")
+      expect($?).to be_a_success
+    end
+
+    it "can be given a block to manually read from the pipe" do
+      expect(
+        subject.popen_read("sh", "-c", "echo success") do |pipe|
+          pipe.read.chomp
+        end,
+      ).to eq("success")
+      expect($?).to be_a_success
+    end
+  end
+
+  describe "::popen_write" do
+    it "with supports writing to a command's standard input" do
+      subject.popen_write("grep", "-q", "success") do |pipe|
+        pipe.write("success\n")
+      end
+      expect($?).to be_a_success
+    end
+  end
+end
diff --git a/Library/Homebrew/test/utils/shell_spec.rb b/Library/Homebrew/test/utils/shell_spec.rb
new file mode 100644
index 000000000..c44bd8253
--- /dev/null
+++ b/Library/Homebrew/test/utils/shell_spec.rb
@@ -0,0 +1,93 @@
+require "utils/shell"
+
+describe Utils::Shell do
+  describe "::shell_profile" do
+    it "returns ~/.bash_profile by default" do
+      ENV["SHELL"] = "/bin/another_shell"
+      expect(subject.shell_profile).to eq("~/.bash_profile")
+    end
+
+    it "returns ~/.bash_profile for Sh" do
+      ENV["SHELL"] = "/bin/another_shell"
+      expect(subject.shell_profile).to eq("~/.bash_profile")
+    end
+
+    it "returns ~/.bash_profile for Bash" do
+      ENV["SHELL"] = "/bin/bash"
+      expect(subject.shell_profile).to eq("~/.bash_profile")
+    end
+
+    it "returns ~/.zshrc for Zsh" do
+      ENV["SHELL"] = "/bin/zsh"
+      expect(subject.shell_profile).to eq("~/.zshrc")
+    end
+
+    it "returns ~/.kshrc for Ksh" do
+      ENV["SHELL"] = "/bin/ksh"
+      expect(subject.shell_profile).to eq("~/.kshrc")
+    end
+  end
+
+  describe "::path_to_shell" do
+    it "supports a raw command name" do
+      expect(subject.path_to_shell("bash")).to eq(:bash)
+    end
+
+    it "supports full paths" do
+      expect(subject.path_to_shell("/bin/bash")).to eq(:bash)
+    end
+
+    it "supports versions" do
+      expect(subject.path_to_shell("zsh-5.2")).to eq(:zsh)
+    end
+
+    it "strips newlines" do
+      expect(subject.path_to_shell("zsh-5.2\n")).to eq(:zsh)
+    end
+
+    it "returns nil when input is invalid" do
+      expect(subject.path_to_shell("")).to be nil
+      expect(subject.path_to_shell("@@@@@@")).to be nil
+      expect(subject.path_to_shell("invalid_shell-4.2")).to be nil
+    end
+  end
+
+  specify "::sh_quote" do
+    expect(subject.sh_quote("")).to eq("''")
+    expect(subject.sh_quote("\\")).to eq("\\\\")
+    expect(subject.sh_quote("\n")).to eq("'\n'")
+    expect(subject.sh_quote("$")).to eq("\\$")
+    expect(subject.sh_quote("word")).to eq("word")
+  end
+
+  specify "::csh_quote" do
+    expect(subject.csh_quote("")).to eq("''")
+    expect(subject.csh_quote("\\")).to eq("\\\\")
+    # note this test is different than for sh
+    expect(subject.csh_quote("\n")).to eq("'\\\n'")
+    expect(subject.csh_quote("$")).to eq("\\$")
+    expect(subject.csh_quote("word")).to eq("word")
+  end
+
+  describe "::prepend_path_in_shell_profile" do
+    let(:path) { "/my/path" }
+
+    it "supports Tcsh" do
+      ENV["SHELL"] = "/bin/tcsh"
+      expect(subject.prepend_path_in_shell_profile(path))
+        .to start_with("echo 'setenv PATH #{path}:$")
+    end
+
+    it "supports Bash" do
+      ENV["SHELL"] = "/bin/bash"
+      expect(subject.prepend_path_in_shell_profile(path))
+        .to start_with("echo 'export PATH=\"#{path}:$")
+    end
+
+    it "supports Fish" do
+      ENV["SHELL"] = "/usr/local/bin/fish"
+      expect(subject.prepend_path_in_shell_profile(path))
+        .to start_with("echo 'set -g fish_user_paths \"#{path}\" $fish_user_paths' >>")
+    end
+  end
+end
diff --git a/Library/Homebrew/test/utils/tty_spec.rb b/Library/Homebrew/test/utils/tty_spec.rb
new file mode 100644
index 000000000..3ba89b6fd
--- /dev/null
+++ b/Library/Homebrew/test/utils/tty_spec.rb
@@ -0,0 +1,67 @@
+require "utils"
+
+describe Tty do
+  describe "::strip_ansi" do
+    it "removes ANSI escape codes from a string" do
+      expect(subject.strip_ansi("\033\[36;7mhello\033\[0m")).to eq("hello")
+    end
+  end
+
+  describe "::width" do
+    it "returns an Integer" do
+      expect(subject.width).to be_kind_of(Integer)
+    end
+
+    it "cannot be negative" do
+      expect(subject.width).to be >= 0
+    end
+  end
+
+  describe "::truncate" do
+    it "truncates the text to the terminal width, minus 4, to account for '==> '" do
+      allow(subject).to receive(:width).and_return(15)
+
+      expect(subject.truncate("foobar something very long")).to eq("foobar some")
+      expect(subject.truncate("truncate")).to eq("truncate")
+    end
+
+    it "doesn't truncate the text if the terminal is unsupported, i.e. the width is 0" do
+      allow(subject).to receive(:width).and_return(0)
+      expect(subject.truncate("foobar something very long")).to eq("foobar something very long")
+    end
+  end
+
+  context "when $stdout is not a TTY" do
+    before(:each) do
+      allow($stdout).to receive(:tty?).and_return(false)
+    end
+
+    it "returns an empty string for all colors" do
+      expect(subject.to_s).to eq("")
+      expect(subject.red.to_s).to eq("")
+      expect(subject.green.to_s).to eq("")
+      expect(subject.yellow.to_s).to eq("")
+      expect(subject.blue.to_s).to eq("")
+      expect(subject.magenta.to_s).to eq("")
+      expect(subject.cyan.to_s).to eq("")
+      expect(subject.default.to_s).to eq("")
+    end
+  end
+
+  context "when $stdout is a TTY" do
+    before(:each) do
+      allow($stdout).to receive(:tty?).and_return(true)
+    end
+
+    it "returns an empty string for all colors" do
+      expect(subject.to_s).to eq("")
+      expect(subject.red.to_s).to eq("\033[31m")
+      expect(subject.green.to_s).to eq("\033[32m")
+      expect(subject.yellow.to_s).to eq("\033[33m")
+      expect(subject.blue.to_s).to eq("\033[34m")
+      expect(subject.magenta.to_s).to eq("\033[35m")
+      expect(subject.cyan.to_s).to eq("\033[36m")
+      expect(subject.default.to_s).to eq("\033[39m")
+    end
+  end
+end
diff --git a/Library/Homebrew/test/utils/tty_test.rb b/Library/Homebrew/test/utils/tty_test.rb
deleted file mode 100644
index 09f092cbd..000000000
--- a/Library/Homebrew/test/utils/tty_test.rb
+++ /dev/null
@@ -1,46 +0,0 @@
-require "testing_env"
-require "utils"
-
-class TtyTests < Homebrew::TestCase
-  def test_strip_ansi
-    assert_equal "hello", Tty.strip_ansi("\033\[36;7mhello\033\[0m")
-  end
-
-  def test_width
-    assert_kind_of Integer, Tty.width
-  end
-
-  def test_truncate
-    Tty.stubs(:width).returns 15
-    assert_equal "foobar some", Tty.truncate("foobar something very long")
-    assert_equal "truncate", Tty.truncate("truncate")
-
-    # When the terminal is unsupported, we report 0 width
-    Tty.stubs(:width).returns 0
-    assert_equal "foobar something very long", Tty.truncate("foobar something very long")
-  end
-
-  def test_no_tty_formatting
-    $stdout.stubs(:tty?).returns false
-    assert_equal "", Tty.to_s
-    assert_equal "", Tty.red.to_s
-    assert_equal "", Tty.green.to_s
-    assert_equal "", Tty.yellow.to_s
-    assert_equal "", Tty.blue.to_s
-    assert_equal "", Tty.magenta.to_s
-    assert_equal "", Tty.cyan.to_s
-    assert_equal "", Tty.default.to_s
-  end
-
-  def test_formatting
-    $stdout.stubs(:tty?).returns(true)
-    assert_equal "",         Tty.to_s
-    assert_equal "\033[31m", Tty.red.to_s
-    assert_equal "\033[32m", Tty.green.to_s
-    assert_equal "\033[33m", Tty.yellow.to_s
-    assert_equal "\033[34m", Tty.blue.to_s
-    assert_equal "\033[35m", Tty.magenta.to_s
-    assert_equal "\033[36m", Tty.cyan.to_s
-    assert_equal "\033[39m", Tty.default.to_s
-  end
-end
diff --git a/Library/Homebrew/test/utils_spec.rb b/Library/Homebrew/test/utils_spec.rb
new file mode 100644
index 000000000..b3fdedcb9
--- /dev/null
+++ b/Library/Homebrew/test/utils_spec.rb
@@ -0,0 +1,277 @@
+require "utils"
+
+describe "globally-scoped helper methods" do
+  let(:dir) { @dir = Pathname.new(Dir.mktmpdir) }
+
+  after(:each) { dir.rmtree unless @dir.nil? }
+
+  def esc(code)
+    /(\e\[\d+m)*\e\[#{code}m/
+  end
+
+  describe "#ofail" do
+    it "sets Homebrew.failed to true" do
+      expect {
+        ofail "foo"
+      }.to output("Error: foo\n").to_stderr
+
+      expect(Homebrew).to have_failed
+    end
+  end
+
+  describe "#odie" do
+    it "exits with 1" do
+      expect(self).to receive(:exit).and_return(1)
+      expect {
+        odie "foo"
+      }.to output("Error: foo\n").to_stderr
+    end
+  end
+
+  describe "#pretty_installed" do
+    subject { pretty_installed("foo") }
+
+    context "when $stdout is a TTY" do
+      before(:each) { allow($stdout).to receive(:tty?).and_return(true) }
+
+      context "with HOMEBREW_NO_EMOJI unset" do
+        before(:each) { ENV.delete("HOMEBREW_NO_EMOJI") }
+
+        it "returns a string with a colored checkmark" do
+          expect(subject)
+            .to match(/#{esc 1}foo #{esc 32}✔#{esc 0}/)
+        end
+      end
+
+      context "with HOMEBREW_NO_EMOJI set" do
+        before(:each) { ENV["HOMEBREW_NO_EMOJI"] = "1" }
+
+        it "returns a string with colored info" do
+          expect(subject)
+            .to match(/#{esc 1}foo \(installed\)#{esc 0}/)
+        end
+      end
+    end
+
+    context "when $stdout is not a TTY" do
+      before(:each) { allow($stdout).to receive(:tty?).and_return(false) }
+
+      it "returns plain text" do
+        expect(subject).to eq("foo")
+      end
+    end
+  end
+
+  describe "#pretty_uninstalled" do
+    subject { pretty_uninstalled("foo") }
+
+    context "when $stdout is a TTY" do
+      before(:each) { allow($stdout).to receive(:tty?).and_return(true) }
+
+      context "with HOMEBREW_NO_EMOJI unset" do
+        before(:each) { ENV.delete("HOMEBREW_NO_EMOJI") }
+
+        it "returns a string with a colored checkmark" do
+          expect(subject)
+            .to match(/#{esc 1}foo #{esc 31}✘#{esc 0}/)
+        end
+      end
+
+      context "with HOMEBREW_NO_EMOJI set" do
+        before(:each) { ENV["HOMEBREW_NO_EMOJI"] = "1" }
+
+        it "returns a string with colored info" do
+          expect(subject)
+            .to match(/#{esc 1}foo \(uninstalled\)#{esc 0}/)
+        end
+      end
+    end
+
+    context "when $stdout is not a TTY" do
+      before(:each) { allow($stdout).to receive(:tty?).and_return(false) }
+
+      it "returns plain text" do
+        expect(subject).to eq("foo")
+      end
+    end
+  end
+
+  describe "#interactive_shell" do
+    let(:shell) { dir/"myshell" }
+
+    it "starts an interactive shell session" do
+      IO.write shell, <<-EOS.undent
+        #!/bin/sh
+        echo called > "#{dir}/called"
+      EOS
+
+      FileUtils.chmod 0755, shell
+
+      ENV["SHELL"] = shell
+
+      expect { interactive_shell }.not_to raise_error
+      expect(dir/"called").to exist
+    end
+  end
+
+  describe "#with_custom_locale" do
+    it "temporarily overrides the system locale" do
+      ENV["LC_ALL"] = "en_US.UTF-8"
+
+      with_custom_locale("C") do
+        expect(ENV["LC_ALL"]).to eq("C")
+      end
+
+      expect(ENV["LC_ALL"]).to eq("en_US.UTF-8")
+    end
+  end
+
+  describe "#run_as_not_developer" do
+    it "temporarily unsets HOMEBREW_DEVELOPER" do
+      ENV["HOMEBREW_DEVELOPER"] = "foo"
+
+      run_as_not_developer do
+        expect(ENV["HOMEBREW_DEVELOPER"]).to be nil
+      end
+
+      expect(ENV["HOMEBREW_DEVELOPER"]).to eq("foo")
+    end
+  end
+
+  describe "#which" do
+    let(:cmd) { dir/"foo" }
+
+    before(:each) { FileUtils.touch cmd }
+
+    it "returns the first executable that is found" do
+      cmd.chmod 0744
+      expect(which(File.basename(cmd), File.dirname(cmd))).to eq(cmd)
+    end
+
+    it "skips non-executables" do
+      expect(which(File.basename(cmd), File.dirname(cmd))).to be nil
+    end
+
+    it "skips malformed path and doesn't fail" do
+      # 'which' should not fail if a path is malformed
+      # see https://github.com/Homebrew/legacy-homebrew/issues/32789 for an example
+      cmd.chmod 0744
+
+      # ~~ will fail because ~foo resolves to foo's home and there is no '~' user
+      path = ["~~", File.dirname(cmd)].join(File::PATH_SEPARATOR)
+      expect(which(File.basename(cmd), path)).to eq(cmd)
+    end
+  end
+
+  describe "#which_all" do
+    let(:cmd1) { dir/"foo" }
+    let(:cmd2) { dir/"bar/foo" }
+    let(:cmd3) { dir/"bar/baz/foo" }
+
+    before(:each) do
+      (dir/"bar/baz").mkpath
+
+      FileUtils.touch cmd2
+
+      [cmd1, cmd3].each do |cmd|
+        FileUtils.touch cmd
+        cmd.chmod 0744
+      end
+    end
+
+    it "returns an array of all executables that are found" do
+      path = [
+        "#{dir}/bar/baz",
+        "#{dir}/baz:#{dir}",
+        "~baduserpath",
+      ].join(File::PATH_SEPARATOR)
+      expect(which_all("foo", path)).to eq([cmd3, cmd1])
+    end
+  end
+
+  specify "#which_editor" do
+    ENV["HOMEBREW_EDITOR"] = "vemate"
+    expect(which_editor).to eq("vemate")
+  end
+
+  specify "#gzip" do
+    Dir.mktmpdir do |path|
+      path = Pathname.new(path)
+      somefile = path/"somefile"
+      FileUtils.touch somefile
+      expect(gzip(somefile)[0].to_s).to eq("#{somefile}.gz")
+      expect(Pathname.new("#{somefile}.gz")).to exist
+    end
+  end
+
+  specify "#capture_stderr" do
+    err = capture_stderr do
+      $stderr.print "test"
+    end
+
+    expect(err).to eq("test")
+  end
+
+  describe "#pretty_duration" do
+    it "converts seconds to a human-readable string" do
+      expect(pretty_duration(1)).to eq("1 second")
+      expect(pretty_duration(2.5)).to eq("2 seconds")
+      expect(pretty_duration(42)).to eq("42 seconds")
+      expect(pretty_duration(240)).to eq("4 minutes")
+      expect(pretty_duration(252.45)).to eq("4 minutes 12 seconds")
+    end
+  end
+
+  specify "#plural" do
+    expect(plural(1)).to eq("")
+    expect(plural(0)).to eq("s")
+    expect(plural(42)).to eq("s")
+    expect(plural(42, "")).to eq("")
+  end
+
+  specify "#disk_usage_readable" do
+    expect(disk_usage_readable(1)).to eq("1B")
+    expect(disk_usage_readable(1000)).to eq("1000B")
+    expect(disk_usage_readable(1024)).to eq("1KB")
+    expect(disk_usage_readable(1025)).to eq("1KB")
+    expect(disk_usage_readable(4_404_020)).to eq("4.2MB")
+    expect(disk_usage_readable(4_509_715_660)).to eq("4.2GB")
+  end
+
+  describe "#number_readable" do
+    it "returns a string with thousands separators" do
+      expect(number_readable(1)).to eq("1")
+      expect(number_readable(1_000)).to eq("1,000")
+      expect(number_readable(1_000_000)).to eq("1,000,000")
+    end
+  end
+
+  specify "#truncate_text_to_approximate_size" do
+    glue = "\n[...snip...]\n" # hard-coded copy from truncate_text_to_approximate_size
+    n = 20
+    long_s = "x" * 40
+
+    s = truncate_text_to_approximate_size(long_s, n)
+    expect(s.length).to eq(n)
+    expect(s).to match(/^x+#{Regexp.escape(glue)}x+$/)
+
+    s = truncate_text_to_approximate_size(long_s, n, front_weight: 0.0)
+    expect(s).to eq(glue + ("x" * (n - glue.length)))
+
+    s = truncate_text_to_approximate_size(long_s, n, front_weight: 1.0)
+    expect(s).to eq(("x" * (n - glue.length)) + glue)
+  end
+
+  describe "#odeprecated" do
+    it "raises a MethodDeprecatedError" do
+      ENV.delete("HOMEBREW_DEVELOPER")
+      expect {
+        odeprecated(
+          "method", "replacement",
+          caller: ["#{HOMEBREW_LIBRARY}/Taps/homebrew/homebrew-core/"],
+          disable: true
+        )
+      }.to raise_error(MethodDeprecatedError, %r{method.*replacement.*homebrew/homebrew-core.*homebrew/core}m)
+    end
+  end
+end
diff --git a/Library/Homebrew/test/utils_test.rb b/Library/Homebrew/test/utils_test.rb
deleted file mode 100644
index d7c25683d..000000000
--- a/Library/Homebrew/test/utils_test.rb
+++ /dev/null
@@ -1,235 +0,0 @@
-require "testing_env"
-require "utils"
-require "tempfile"
-require "utils/shell"
-
-class UtilTests < Homebrew::TestCase
-  def setup
-    @dir = Pathname.new(mktmpdir)
-    @env = ENV.to_hash
-  end
-
-  def teardown
-    @dir.rmtree
-    ENV.replace @env
-  end
-
-  def test_ofail
-    shutup { ofail "foo" }
-    assert Homebrew.failed?
-  ensure
-    Homebrew.failed = false
-  end
-
-  def test_odie
-    expects(:exit).returns 1
-    shutup { odie "foo" }
-  end
-
-  def test_pretty_installed
-    $stdout.stubs(:tty?).returns false
-    assert_equal "foo", pretty_installed("foo")
-  end
-
-  def test_pretty_uninstalled
-    $stdout.stubs(:tty?).returns false
-    assert_equal "foo", pretty_uninstalled("foo")
-  end
-
-  def test_interactive_shell
-    mktmpdir do |path|
-      shell = "#{path}/myshell"
-      File.open(shell, "w") do |file|
-        file.write "#!/bin/sh\necho called > #{path}/called\n"
-      end
-      FileUtils.chmod 0755, shell
-      ENV["SHELL"] = shell
-      assert_nothing_raised { interactive_shell }
-      assert File.exist? "#{path}/called"
-    end
-  end
-
-  def test_with_custom_locale
-    ENV["LC_ALL"] = "en_US.UTF-8"
-    with_custom_locale("C") do
-      assert_equal "C", ENV["LC_ALL"]
-    end
-    assert_equal "en_US.UTF-8", ENV["LC_ALL"]
-  end
-
-  def test_run_as_not_developer
-    ENV["HOMEBREW_DEVELOPER"] = "foo"
-    run_as_not_developer do
-      assert_nil ENV["HOMEBREW_DEVELOPER"]
-    end
-    assert_equal "foo", ENV["HOMEBREW_DEVELOPER"]
-  end
-
-  def test_put_columns_empty
-    out, err = capture_io do
-      puts Formatter.columns([])
-    end
-
-    assert_equal out, "\n"
-    assert_equal err, ""
-  end
-
-  def test_which
-    cmd = @dir/"foo"
-    FileUtils.touch cmd
-    cmd.chmod 0744
-    assert_equal Pathname.new(cmd),
-      which(File.basename(cmd), File.dirname(cmd))
-  end
-
-  def test_which_skip_non_executables
-    cmd = @dir/"foo"
-    FileUtils.touch cmd
-    assert_nil which(File.basename(cmd), File.dirname(cmd))
-  end
-
-  def test_which_skip_malformed_path
-    # 'which' should not fail if a path is malformed
-    # see https://github.com/Homebrew/legacy-homebrew/issues/32789 for an example
-    cmd = @dir/"foo"
-    FileUtils.touch cmd
-    cmd.chmod 0744
-
-    # ~~ will fail because ~foo resolves to foo's home and there is no '~' user
-    # here
-    assert_equal Pathname.new(cmd),
-      which(File.basename(cmd), "~~#{File::PATH_SEPARATOR}#{File.dirname(cmd)}")
-  end
-
-  def test_which_all
-    (@dir/"bar/baz").mkpath
-    cmd1 = @dir/"foo"
-    cmd2 = @dir/"bar/foo"
-    cmd3 = @dir/"bar/baz/foo"
-    FileUtils.touch cmd2
-    [cmd1, cmd3].each do |cmd|
-      FileUtils.touch cmd
-      cmd.chmod 0744
-    end
-    assert_equal [cmd3, cmd1],
-      which_all("foo", "#{@dir}/bar/baz:#{@dir}/baz:#{@dir}:~baduserpath")
-  end
-
-  def test_which_editor
-    ENV["HOMEBREW_EDITOR"] = "vemate"
-    assert_equal "vemate", which_editor
-  end
-
-  def test_gzip
-    mktmpdir do |path|
-      somefile = "#{path}/somefile"
-      FileUtils.touch somefile
-      assert_equal "#{somefile}.gz",
-        gzip(somefile)[0].to_s
-      assert File.exist?("#{somefile}.gz")
-    end
-  end
-
-  def test_capture_stderr
-    assert_equal "test\n", capture_stderr { $stderr.puts "test" }
-  end
-
-  def test_shell_profile
-    ENV["SHELL"] = "/bin/sh"
-    assert_equal "~/.bash_profile", Utils::Shell.shell_profile
-    ENV["SHELL"] = "/bin/bash"
-    assert_equal "~/.bash_profile", Utils::Shell.shell_profile
-    ENV["SHELL"] = "/bin/another_shell"
-    assert_equal "~/.bash_profile", Utils::Shell.shell_profile
-    ENV["SHELL"] = "/bin/zsh"
-    assert_equal "~/.zshrc", Utils::Shell.shell_profile
-    ENV["SHELL"] = "/bin/ksh"
-    assert_equal "~/.kshrc", Utils::Shell.shell_profile
-  end
-
-  def test_popen_read
-    out = Utils.popen_read("sh", "-c", "echo success").chomp
-    assert_equal "success", out
-    assert_predicate $?, :success?
-  end
-
-  def test_popen_read_with_block
-    out = Utils.popen_read("sh", "-c", "echo success") do |pipe|
-      pipe.read.chomp
-    end
-    assert_equal "success", out
-    assert_predicate $?, :success?
-  end
-
-  def test_popen_write_with_block
-    Utils.popen_write("grep", "-q", "success") do |pipe|
-      pipe.write("success\n")
-    end
-    assert_predicate $?, :success?
-  end
-
-  def test_pretty_duration
-    assert_equal "1 second", pretty_duration(1)
-    assert_equal "2 seconds", pretty_duration(2.5)
-    assert_equal "42 seconds", pretty_duration(42)
-    assert_equal "4 minutes", pretty_duration(240)
-    assert_equal "4 minutes 12 seconds", pretty_duration(252.45)
-  end
-
-  def test_plural
-    assert_equal "", plural(1)
-    assert_equal "s", plural(0)
-    assert_equal "s", plural(42)
-    assert_equal "", plural(42, "")
-  end
-
-  def test_disk_usage_readable
-    assert_equal "1B", disk_usage_readable(1)
-    assert_equal "1000B", disk_usage_readable(1000)
-    assert_equal "1K", disk_usage_readable(1024)
-    assert_equal "1K", disk_usage_readable(1025)
-    assert_equal "4.2M", disk_usage_readable(4_404_020)
-    assert_equal "4.2G", disk_usage_readable(4_509_715_660)
-  end
-
-  def test_number_readable
-    assert_equal "1", number_readable(1)
-    assert_equal "1,000", number_readable(1_000)
-    assert_equal "1,000,000", number_readable(1_000_000)
-  end
-
-  def test_truncate_text_to_approximate_size
-    glue = "\n[...snip...]\n" # hard-coded copy from truncate_text_to_approximate_size
-    n = 20
-    long_s = "x" * 40
-    s = truncate_text_to_approximate_size(long_s, n)
-    assert_equal n, s.length
-    assert_match(/^x+#{Regexp.escape(glue)}x+$/, s)
-    s = truncate_text_to_approximate_size(long_s, n, front_weight: 0.0)
-    assert_equal glue + ("x" * (n - glue.length)), s
-    s = truncate_text_to_approximate_size(long_s, n, front_weight: 1.0)
-    assert_equal(("x" * (n - glue.length)) + glue, s)
-  end
-
-  def test_odeprecated
-    ARGV.stubs(:homebrew_developer?).returns false
-    e = assert_raises(MethodDeprecatedError) do
-      odeprecated("method", "replacement",
-        caller: ["#{HOMEBREW_LIBRARY}/Taps/homebrew/homebrew-core/"],
-        disable: true)
-    end
-    assert_match "method", e.message
-    assert_match "replacement", e.message
-    assert_match "homebrew/homebrew-core", e.message
-    assert_match "homebrew/core", e.message
-  end
-
-  def test_bottles_bintray
-    assert_equal "openssl:1.1", Utils::Bottles::Bintray.package("openssl@1.1")
-    assert_equal "gtkx", Utils::Bottles::Bintray.package("gtk+")
-    assert_equal "llvm", Utils::Bottles::Bintray.package("llvm")
-
-    tap = Tap.new("homebrew", "bintray-test")
-    assert_equal "bottles-bintray-test", Utils::Bottles::Bintray.repository(tap)
-  end
-end
diff --git a/Library/Homebrew/test/version_test.rb b/Library/Homebrew/test/version_test.rb
deleted file mode 100644
index e7ffbc4f6..000000000
--- a/Library/Homebrew/test/version_test.rb
+++ /dev/null
@@ -1,8 +0,0 @@
-require "testing_env"
-
-class IntegrationCommandTestVersion < IntegrationCommandTestCase
-  def test_version
-    assert_match HOMEBREW_VERSION.to_s,
-                 cmd("--version")
-  end
-end
diff --git a/Library/Homebrew/test/versions_test.rb b/Library/Homebrew/test/versions_test.rb
index a6e922178..b6814b1d1 100644
--- a/Library/Homebrew/test/versions_test.rb
+++ b/Library/Homebrew/test/versions_test.rb
@@ -185,8 +185,6 @@ class VersionParsingTests < Homebrew::TestCase
     d = HOMEBREW_CELLAR/"foo-0.1.9"
     d.mkpath
     assert_equal version("0.1.9"), d.version
-  ensure
-    d.unlink
   end
 
   def test_no_version
diff --git a/Library/Homebrew/test/x11_requirement_spec.rb b/Library/Homebrew/test/x11_requirement_spec.rb
new file mode 100644
index 000000000..f60c8bffe
--- /dev/null
+++ b/Library/Homebrew/test/x11_requirement_spec.rb
@@ -0,0 +1,36 @@
+require "requirements/x11_requirement"
+
+describe X11Requirement do
+  let(:default_name) { "x11" }
+
+  describe "#name" do
+    it "defaults to x11" do
+      expect(subject.name).to eq(default_name)
+    end
+  end
+
+  describe "#eql?" do
+    it "returns true if the names are equal" do
+      other = described_class.new(default_name)
+      expect(subject).to eql(other)
+    end
+
+    it "and returns false if the names differ" do
+      other = described_class.new("foo")
+      expect(subject).not_to eql(other)
+    end
+
+    it "returns false if the minimum version differs" do
+      other = described_class.new(default_name, ["2.5"])
+      expect(subject).not_to eql(other)
+    end
+  end
+
+  describe "#modify_build_environment" do
+    it "calls ENV#x11" do
+      allow(subject).to receive(:satisfied?).and_return(true)
+      expect(ENV).to receive(:x11)
+      subject.modify_build_environment
+    end
+  end
+end
diff --git a/Library/Homebrew/test/x11_requirement_test.rb b/Library/Homebrew/test/x11_requirement_test.rb
deleted file mode 100644
index b82a59e53..000000000
--- a/Library/Homebrew/test/x11_requirement_test.rb
+++ /dev/null
@@ -1,31 +0,0 @@
-require "testing_env"
-require "requirements/x11_requirement"
-
-class X11RequirementTests < Homebrew::TestCase
-  def test_eql_instances_are_eql
-    x = X11Requirement.new
-    y = X11Requirement.new
-    assert_eql x, y
-    assert_equal x.hash, y.hash
-  end
-
-  def test_not_eql_when_hashes_differ
-    x = X11Requirement.new("foo")
-    y = X11Requirement.new
-    refute_eql x, y
-    refute_equal x.hash, y.hash
-  end
-
-  def test_different_min_version
-    x = X11Requirement.new
-    y = X11Requirement.new("x11", %w[2.5])
-    refute_eql x, y
-  end
-
-  def test_x_env
-    x = X11Requirement.new
-    x.stubs(:satisfied?).returns(true)
-    ENV.expects(:x11)
-    x.modify_build_environment
-  end
-end