From af40e072b0634e30224022de81ade98128cd63c7 Mon Sep 17 00:00:00 2001
From: Rylan Polster <rslpolster@gmail.com>
Date: Sun, 31 Jan 2021 13:14:23 -0500
Subject: [PATCH] style: remove RSpec/NamedSubject violations

---
 Library/Homebrew/test/ENV_spec.rb             |  28 ++--
 .../Homebrew/test/build_environment_spec.rb   |   6 +-
 Library/Homebrew/test/build_options_spec.rb   |  18 +--
 Library/Homebrew/test/cache_store_spec.rb     |  46 +++---
 Library/Homebrew/test/cask/audit_spec.rb      |  66 ++++----
 .../Homebrew/test/cask/dsl/appcast_spec.rb    |   6 +-
 Library/Homebrew/test/caveats_spec.rb         |   6 +-
 Library/Homebrew/test/cleaner_spec.rb         |  38 ++---
 Library/Homebrew/test/cleanup_spec.rb         |  44 +++---
 Library/Homebrew/test/cmd/info_spec.rb        |   8 +-
 .../Homebrew/test/compiler_selector_spec.rb   |  12 +-
 Library/Homebrew/test/dependable_spec.rb      |  10 +-
 Library/Homebrew/test/dependencies_spec.rb    |  50 +++---
 .../test/dependency_collector_spec.rb         |  42 ++---
 Library/Homebrew/test/dependency_spec.rb      |   6 +-
 Library/Homebrew/test/descriptions_spec.rb    |  10 +-
 .../Homebrew/test/diagnostic_checks_spec.rb   |  32 ++--
 .../Homebrew/test/download_strategies_spec.rb |  88 +++++------
 .../test/error_during_execution_spec.rb       |   4 +-
 Library/Homebrew/test/exceptions_spec.rb      |  26 ++--
 Library/Homebrew/test/formatter_spec.rb       |   8 +-
 Library/Homebrew/test/formula_pin_spec.rb     |  14 +-
 Library/Homebrew/test/language/node_spec.rb   |  20 +--
 Library/Homebrew/test/language/python_spec.rb |  30 ++--
 .../Homebrew/test/linkage_cache_store_spec.rb |  16 +-
 Library/Homebrew/test/locale_spec.rb          |   8 +-
 Library/Homebrew/test/lock_file_spec.rb       |  14 +-
 Library/Homebrew/test/migrator_spec.rb        |  40 ++---
 Library/Homebrew/test/options_spec.rb         | 100 ++++++------
 .../os/linux/dependency_collector_spec.rb     |  14 +-
 .../Homebrew/test/os/linux/diagnostic_spec.rb |   8 +-
 .../test/os/mac/dependency_collector_spec.rb  |  14 +-
 .../Homebrew/test/os/mac/diagnostic_spec.rb   |   8 +-
 Library/Homebrew/test/os/mac/keg_spec.rb      |  12 +-
 Library/Homebrew/test/os/mac_spec.rb          |   4 +-
 Library/Homebrew/test/patch_spec.rb           |  24 +--
 Library/Homebrew/test/requirement_spec.rb     |  34 ++--
 Library/Homebrew/test/requirements_spec.rb    |   8 +-
 Library/Homebrew/test/resource_spec.rb        | 112 +++++++-------
 Library/Homebrew/test/sandbox_spec.rb         |  12 +-
 Library/Homebrew/test/searchable_spec.rb      |  14 +-
 Library/Homebrew/test/software_spec_spec.rb   | 144 ++++++++---------
 .../test/system_command_result_spec.rb        |  18 +--
 Library/Homebrew/test/tab_spec.rb             |  68 ++++----
 Library/Homebrew/test/tap_spec.rb             | 146 +++++++++---------
 Library/Homebrew/test/utils_spec.rb           |  16 +-
 Library/Homebrew/test/version_spec.rb         |   6 +-
 47 files changed, 744 insertions(+), 714 deletions(-)

diff --git a/Library/Homebrew/test/ENV_spec.rb b/Library/Homebrew/test/ENV_spec.rb
index c0f1be5328..9a68c60a5d 100644
--- a/Library/Homebrew/test/ENV_spec.rb
+++ b/Library/Homebrew/test/ENV_spec.rb
@@ -4,9 +4,9 @@
 require "extend/ENV"
 
 shared_examples EnvActivation do
-  subject { env.extend(described_class) }
+  subject(:env) { env_activation.extend(described_class) }
 
-  let(:env) { {}.extend(EnvActivation) }
+  let(:env_activation) { {}.extend(EnvActivation) }
 
   it "supports switching compilers" do
     subject.clang
@@ -180,28 +180,28 @@ describe Superenv do
   include_examples EnvActivation
 
   it "initializes deps" do
-    expect(subject.deps).to eq([])
-    expect(subject.keg_only_deps).to eq([])
+    expect(env.deps).to eq([])
+    expect(env.keg_only_deps).to eq([])
   end
 
   describe "#cxx11" do
     it "supports gcc-5" do
-      subject["HOMEBREW_CC"] = "gcc-5"
-      subject.cxx11
-      expect(subject["HOMEBREW_CCCFG"]).to include("x")
+      env["HOMEBREW_CC"] = "gcc-5"
+      env.cxx11
+      expect(env["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")
+      env["HOMEBREW_CC"] = "gcc-6"
+      env.cxx11
+      expect(env["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")
+      env["HOMEBREW_CC"] = "clang"
+      env.cxx11
+      expect(env["HOMEBREW_CCCFG"]).to include("x")
+      expect(env["HOMEBREW_CCCFG"]).to include("g")
     end
   end
 end
diff --git a/Library/Homebrew/test/build_environment_spec.rb b/Library/Homebrew/test/build_environment_spec.rb
index 79f8a57e85..0e874c31fb 100644
--- a/Library/Homebrew/test/build_environment_spec.rb
+++ b/Library/Homebrew/test/build_environment_spec.rb
@@ -43,11 +43,11 @@ describe BuildEnvironment do
   end
 
   describe BuildEnvironment::DSL do
-    subject { double.extend(described_class) }
+    subject(:build_environment_dsl) { double.extend(described_class) }
 
     context "single argument" do
       before do
-        subject.instance_eval do
+        build_environment_dsl.instance_eval do
           env :userpaths
         end
       end
@@ -57,7 +57,7 @@ describe BuildEnvironment do
 
     context "multiple arguments" do
       before do
-        subject.instance_eval do
+        build_environment_dsl.instance_eval do
           env :userpaths, :std
         end
       end
diff --git a/Library/Homebrew/test/build_options_spec.rb b/Library/Homebrew/test/build_options_spec.rb
index f7693171f8..a36d8314d6 100644
--- a/Library/Homebrew/test/build_options_spec.rb
+++ b/Library/Homebrew/test/build_options_spec.rb
@@ -8,7 +8,7 @@ describe BuildOptions do
   alias_matcher :be_built_with, :be_with
   alias_matcher :be_built_without, :be_without
 
-  subject { described_class.new(args, opts) }
+  subject(:build_options) { 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]) }
@@ -16,22 +16,22 @@ describe BuildOptions do
   let(:bad_args) { Options.create(%w[--with-foo --with-bar --without-bas --without-qux --without-abc]) }
 
   specify "#with?" do
-    expect(subject).to be_built_with("foo")
-    expect(subject).to be_built_with("bar")
-    expect(subject).to be_built_with("baz")
+    expect(build_options).to be_built_with("foo")
+    expect(build_options).to be_built_with("bar")
+    expect(build_options).to be_built_with("baz")
   end
 
   specify "#without?" do
-    expect(subject).to be_built_without("qux")
-    expect(subject).to be_built_without("xyz")
+    expect(build_options).to be_built_without("qux")
+    expect(build_options).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")
+    expect(build_options.used_options).to include("--with-foo")
+    expect(build_options.used_options).to include("--with-bar")
   end
 
   specify "#unused_options" do
-    expect(subject.unused_options).to include("--without-baz")
+    expect(build_options.unused_options).to include("--without-baz")
   end
 end
diff --git a/Library/Homebrew/test/cache_store_spec.rb b/Library/Homebrew/test/cache_store_spec.rb
index 2b122fed4c..78acf07751 100644
--- a/Library/Homebrew/test/cache_store_spec.rb
+++ b/Library/Homebrew/test/cache_store_spec.rb
@@ -4,7 +4,7 @@
 require "cache_store"
 
 describe CacheStoreDatabase do
-  subject { described_class.new(:sample) }
+  subject(:sample_db) { described_class.new(:sample) }
 
   describe "self.use" do
     let(:type) { :test }
@@ -22,12 +22,12 @@ describe CacheStoreDatabase do
 
     it "sets the value in the `CacheStoreDatabase`" do
       allow(File).to receive(:write)
-      allow(subject).to receive(:created?).and_return(true)
-      allow(subject).to receive(:db).and_return(db)
+      allow(sample_db).to receive(:created?).and_return(true)
+      allow(sample_db).to receive(:db).and_return(db)
 
       expect(db).to receive(:has_key?).with(:foo).and_return(false)
       expect(db).not_to have_key(:foo)
-      subject.set(:foo, "bar")
+      sample_db.set(:foo, "bar")
     end
   end
 
@@ -36,11 +36,11 @@ describe CacheStoreDatabase do
       let(:db) { double("db", :[] => "bar") }
 
       it "gets value in the `CacheStoreDatabase` corresponding to the key" do
-        allow(subject).to receive(:created?).and_return(true)
+        allow(sample_db).to receive(:created?).and_return(true)
         expect(db).to receive(:has_key?).with(:foo).and_return(true)
-        allow(subject).to receive(:db).and_return(db)
+        allow(sample_db).to receive(:db).and_return(db)
         expect(db).to have_key(:foo)
-        expect(subject.get(:foo)).to eq("bar")
+        expect(sample_db.get(:foo)).to eq("bar")
       end
     end
 
@@ -48,17 +48,17 @@ describe CacheStoreDatabase do
       let(:db) { double("db", :[] => nil) }
 
       before do
-        allow(subject).to receive(:created?).and_return(false)
-        allow(subject).to receive(:db).and_return(db)
+        allow(sample_db).to receive(:created?).and_return(false)
+        allow(sample_db).to receive(:db).and_return(db)
       end
 
       it "does not get value in the `CacheStoreDatabase` corresponding to key" do
-        expect(subject.get(:foo)).not_to be("bar")
+        expect(sample_db.get(:foo)).not_to be("bar")
       end
 
       it "does not call `db[]` if `CacheStoreDatabase.created?` is `false`" do
         expect(db).not_to receive(:[])
-        subject.get(:foo)
+        sample_db.get(:foo)
       end
     end
   end
@@ -68,13 +68,13 @@ describe CacheStoreDatabase do
       let(:db) { double("db", :[] => { foo: "bar" }) }
 
       before do
-        allow(subject).to receive(:created?).and_return(true)
-        allow(subject).to receive(:db).and_return(db)
+        allow(sample_db).to receive(:created?).and_return(true)
+        allow(sample_db).to receive(:db).and_return(db)
       end
 
       it "deletes value in the `CacheStoreDatabase` corresponding to the key" do
         expect(db).to receive(:delete).with(:foo)
-        subject.delete(:foo)
+        sample_db.delete(:foo)
       end
     end
 
@@ -82,13 +82,13 @@ describe CacheStoreDatabase do
       let(:db) { double("db", delete: nil) }
 
       before do
-        allow(subject).to receive(:created?).and_return(false)
-        allow(subject).to receive(:db).and_return(db)
+        allow(sample_db).to receive(:created?).and_return(false)
+        allow(sample_db).to receive(:db).and_return(db)
       end
 
       it "does not call `db.delete` if `CacheStoreDatabase.created?` is `false`" do
         expect(db).not_to receive(:delete)
-        subject.delete(:foo)
+        sample_db.delete(:foo)
       end
     end
   end
@@ -96,17 +96,17 @@ describe CacheStoreDatabase do
   describe "#write_if_dirty!" do
     context "database open" do
       it "does not raise an error when `close` is called on the database" do
-        expect { subject.write_if_dirty! }.not_to raise_error(NoMethodError)
+        expect { sample_db.write_if_dirty! }.not_to raise_error(NoMethodError)
       end
     end
 
     context "database not open" do
       before do
-        subject.instance_variable_set(:@db, nil)
+        sample_db.instance_variable_set(:@db, nil)
       end
 
       it "does not raise an error when `close` is called on the database" do
-        expect { subject.write_if_dirty! }.not_to raise_error(NoMethodError)
+        expect { sample_db.write_if_dirty! }.not_to raise_error(NoMethodError)
       end
     end
   end
@@ -115,7 +115,7 @@ describe CacheStoreDatabase do
     let(:cache_path) { Pathname("path/to/homebrew/cache/sample.json") }
 
     before do
-      allow(subject).to receive(:cache_path).and_return(cache_path)
+      allow(sample_db).to receive(:cache_path).and_return(cache_path)
     end
 
     context "`cache_path.exist?` returns `true`" do
@@ -124,7 +124,7 @@ describe CacheStoreDatabase do
       end
 
       it "returns `true`" do
-        expect(subject.created?).to be(true)
+        expect(sample_db.created?).to be(true)
       end
     end
 
@@ -134,7 +134,7 @@ describe CacheStoreDatabase do
       end
 
       it "returns `false`" do
-        expect(subject.created?).to be(false)
+        expect(sample_db.created?).to be(false)
       end
     end
   end
diff --git a/Library/Homebrew/test/cask/audit_spec.rb b/Library/Homebrew/test/cask/audit_spec.rb
index 8eb3efed2c..4896353fea 100644
--- a/Library/Homebrew/test/cask/audit_spec.rb
+++ b/Library/Homebrew/test/cask/audit_spec.rb
@@ -106,7 +106,7 @@ describe Cask::Audit, :cask do
   end
 
   describe "#run!" do
-    subject { audit.run! }
+    subject(:run) { audit.run! }
 
     def tmp_cask(name, text)
       path = Pathname.new "#{dir}/#{name}.rb"
@@ -149,7 +149,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "Upper-Case" }
 
         it "fails" do
-          expect(subject).to fail_with(/lowercase/)
+          expect(run).to fail_with(/lowercase/)
         end
       end
 
@@ -157,7 +157,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "ascii⌘" }
 
         it "fails" do
-          expect(subject).to fail_with(/contains non-ascii characters/)
+          expect(run).to fail_with(/contains non-ascii characters/)
         end
       end
 
@@ -165,7 +165,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "app++" }
 
         it "fails" do
-          expect(subject).to fail_with(/\+ should be replaced by -plus-/)
+          expect(run).to fail_with(/\+ should be replaced by -plus-/)
         end
       end
 
@@ -173,7 +173,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "app@stuff" }
 
         it "fails" do
-          expect(subject).to fail_with(/@ should be replaced by -at-/)
+          expect(run).to fail_with(/@ should be replaced by -at-/)
         end
       end
 
@@ -181,7 +181,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "app stuff" }
 
         it "fails" do
-          expect(subject).to fail_with(/whitespace should be replaced by hyphens/)
+          expect(run).to fail_with(/whitespace should be replaced by hyphens/)
         end
       end
 
@@ -189,7 +189,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "app_stuff" }
 
         it "fails" do
-          expect(subject).to fail_with(/underscores should be replaced by hyphens/)
+          expect(run).to fail_with(/underscores should be replaced by hyphens/)
         end
       end
 
@@ -197,7 +197,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "app(stuff)" }
 
         it "fails" do
-          expect(subject).to fail_with(/alphanumeric characters and hyphens/)
+          expect(run).to fail_with(/alphanumeric characters and hyphens/)
         end
       end
 
@@ -205,7 +205,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "app--stuff" }
 
         it "fails" do
-          expect(subject).to fail_with(/should not contain double hyphens/)
+          expect(run).to fail_with(/should not contain double hyphens/)
         end
       end
 
@@ -213,7 +213,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "-app" }
 
         it "fails" do
-          expect(subject).to fail_with(/should not have leading or trailing hyphens/)
+          expect(run).to fail_with(/should not have leading or trailing hyphens/)
         end
       end
 
@@ -221,7 +221,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "app-" }
 
         it "fails" do
-          expect(subject).to fail_with(/should not have leading or trailing hyphens/)
+          expect(run).to fail_with(/should not have leading or trailing hyphens/)
         end
       end
     end
@@ -247,7 +247,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "token.app" }
 
         it "fails" do
-          expect(subject).to fail_with(/token contains .app/)
+          expect(run).to fail_with(/token contains .app/)
         end
       end
 
@@ -257,13 +257,13 @@ describe Cask::Audit, :cask do
         it "fails if the cask is from an official tap" do
           allow(cask).to receive(:tap).and_return(Tap.fetch("homebrew/cask"))
 
-          expect(subject).to fail_with(/token contains version designation/)
+          expect(run).to fail_with(/token contains version designation/)
         end
 
         it "does not fail if the cask is from the `cask-versions` tap" do
           allow(cask).to receive(:tap).and_return(Tap.fetch("homebrew/cask-versions"))
 
-          expect(subject).to pass
+          expect(run).to pass
         end
       end
 
@@ -271,7 +271,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "token-launcher" }
 
         it "fails" do
-          expect(subject).to fail_with(/token mentions launcher/)
+          expect(run).to fail_with(/token mentions launcher/)
         end
       end
 
@@ -279,7 +279,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "token-desktop" }
 
         it "fails" do
-          expect(subject).to fail_with(/token mentions desktop/)
+          expect(run).to fail_with(/token mentions desktop/)
         end
       end
 
@@ -287,7 +287,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "token-osx" }
 
         it "fails" do
-          expect(subject).to fail_with(/token mentions platform/)
+          expect(run).to fail_with(/token mentions platform/)
         end
       end
 
@@ -295,7 +295,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "token-x86" }
 
         it "fails" do
-          expect(subject).to fail_with(/token mentions architecture/)
+          expect(run).to fail_with(/token mentions architecture/)
         end
       end
 
@@ -303,7 +303,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "token-java" }
 
         it "fails" do
-          expect(subject).to fail_with(/cask token mentions framework/)
+          expect(run).to fail_with(/cask token mentions framework/)
         end
       end
 
@@ -311,7 +311,7 @@ describe Cask::Audit, :cask do
         let(:cask_token) { "java" }
 
         it "does not fail" do
-          expect(subject).to pass
+          expect(run).to pass
         end
       end
 
@@ -328,7 +328,7 @@ describe Cask::Audit, :cask do
           let(:new_cask) { true }
 
           it "fails" do
-            expect(subject).to fail_with("#{cask_token} is listed in tap_migrations.json")
+            expect(run).to fail_with("#{cask_token} is listed in tap_migrations.json")
           end
         end
 
@@ -336,7 +336,7 @@ describe Cask::Audit, :cask do
           let(:new_cask) { false }
 
           it "does not fail" do
-            expect(subject).to pass
+            expect(run).to pass
           end
         end
       end
@@ -382,9 +382,9 @@ describe Cask::Audit, :cask do
 
       context "when cask locale is invalid" do
         it "error with invalid locale" do
-          expect(subject).to fail_with(/Locale 'ZH-CN' is invalid\./)
-          expect(subject).to fail_with(/Locale 'zh-' is invalid\./)
-          expect(subject).to fail_with(/Locale 'zh-cn' is invalid\./)
+          expect(run).to fail_with(/Locale 'ZH-CN' is invalid\./)
+          expect(run).to fail_with(/Locale 'zh-' is invalid\./)
+          expect(run).to fail_with(/Locale 'zh-cn' is invalid\./)
         end
       end
     end
@@ -797,7 +797,7 @@ describe Cask::Audit, :cask do
 
         context "when doing the audit" do
           it "evaluates the block" do
-            expect(subject).to fail_with(/Boom/)
+            expect(run).to fail_with(/Boom/)
           end
         end
       end
@@ -812,7 +812,7 @@ describe Cask::Audit, :cask do
 
         it "warns about duplicates" do
           expect(audit).to receive(:core_formula_names).and_return(formula_names)
-          expect(subject).to warn_with(/possible duplicate/)
+          expect(run).to warn_with(/possible duplicate/)
         end
       end
 
@@ -836,12 +836,12 @@ describe Cask::Audit, :cask do
 
       it "when download and verification succeed it does not fail" do
         expect(download_double).to receive(:fetch)
-        expect(subject).to pass
+        expect(run).to pass
       end
 
       it "when download fails it fails" do
         expect(download_double).to receive(:fetch).and_raise(StandardError.new(message))
-        expect(subject).to fail_with(/#{message}/)
+        expect(run).to fail_with(/#{message}/)
       end
     end
 
@@ -850,7 +850,7 @@ describe Cask::Audit, :cask do
 
       it "fails the audit" do
         expect(cask).to receive(:tap).and_raise(StandardError.new)
-        expect(subject).to fail_with(/exception while auditing/)
+        expect(run).to fail_with(/exception while auditing/)
       end
     end
 
@@ -873,7 +873,7 @@ describe Cask::Audit, :cask do
         let(:new_cask) { true }
 
         it "fails" do
-          expect(subject).to fail_with(/should have a description/)
+          expect(run).to fail_with(/should have a description/)
         end
       end
 
@@ -881,7 +881,7 @@ describe Cask::Audit, :cask do
         let(:new_cask) { false }
 
         it "warns" do
-          expect(subject).to warn_with(/should have a description/)
+          expect(run).to warn_with(/should have a description/)
         end
       end
     end
@@ -903,7 +903,7 @@ describe Cask::Audit, :cask do
       end
 
       it "passes" do
-        expect(subject).to pass
+        expect(run).to pass
       end
     end
 
diff --git a/Library/Homebrew/test/cask/dsl/appcast_spec.rb b/Library/Homebrew/test/cask/dsl/appcast_spec.rb
index 692738b9e1..f6ba18aef4 100644
--- a/Library/Homebrew/test/cask/dsl/appcast_spec.rb
+++ b/Library/Homebrew/test/cask/dsl/appcast_spec.rb
@@ -2,7 +2,7 @@
 # frozen_string_literal: true
 
 describe Cask::DSL::Appcast do
-  subject { described_class.new(url, params) }
+  subject(:appcast) { described_class.new(url, params) }
 
   let(:url) { "https://brew.sh" }
   let(:uri) { URI(url) }
@@ -10,7 +10,7 @@ describe Cask::DSL::Appcast do
 
   describe "#to_s" do
     it "returns the parsed URI string" do
-      expect(subject.to_s).to eq("https://brew.sh")
+      expect(appcast.to_s).to eq("https://brew.sh")
     end
   end
 
@@ -19,7 +19,7 @@ describe Cask::DSL::Appcast do
 
     context "with empty parameters" do
       it "returns an YAML serialized array composed of the URI and parameters" do
-        expect(subject.to_yaml).to eq(yaml)
+        expect(appcast.to_yaml).to eq(yaml)
       end
     end
   end
diff --git a/Library/Homebrew/test/caveats_spec.rb b/Library/Homebrew/test/caveats_spec.rb
index 922dc4a930..c2cbeb5205 100644
--- a/Library/Homebrew/test/caveats_spec.rb
+++ b/Library/Homebrew/test/caveats_spec.rb
@@ -5,17 +5,17 @@ require "formula"
 require "caveats"
 
 describe Caveats do
-  subject { described_class.new(f) }
+  subject(:caveats) { described_class.new(f) }
 
   let(:f) { formula { url "foo-1.0" } }
 
   specify "#f" do
-    expect(subject.f).to eq(f)
+    expect(caveats.f).to eq(f)
   end
 
   describe "#empty?" do
     it "returns true if the Formula has no caveats" do
-      expect(subject).to be_empty
+      expect(caveats).to be_empty
     end
 
     it "returns false if the Formula has caveats" do
diff --git a/Library/Homebrew/test/cleaner_spec.rb b/Library/Homebrew/test/cleaner_spec.rb
index f3ec58552e..dee1108929 100644
--- a/Library/Homebrew/test/cleaner_spec.rb
+++ b/Library/Homebrew/test/cleaner_spec.rb
@@ -7,7 +7,7 @@ require "formula"
 describe Cleaner do
   include FileUtils
 
-  subject { described_class.new(f) }
+  subject(:cleaner) { described_class.new(f) }
 
   let(:f) { formula("cleaner_test") { url "foo-1.0" } }
 
@@ -28,7 +28,7 @@ describe Cleaner do
         cp Dir["#{TEST_FIXTURE_DIR}/elf/libhello.so.0"], f.lib
       end
 
-      subject.clean
+      cleaner.clean
 
       if OS.mac?
         expect((f.bin/"a.out").stat.mode).to eq(0100555)
@@ -42,7 +42,7 @@ describe Cleaner do
     end
 
     it "prunes the prefix if it is empty" do
-      subject.clean
+      cleaner.clean
       expect(f.prefix).not_to be_a_directory
     end
 
@@ -50,7 +50,7 @@ describe Cleaner do
       subdir = f.bin/"subdir"
       subdir.mkpath
 
-      subject.clean
+      cleaner.clean
 
       expect(f.bin).not_to be_a_directory
       expect(subdir).not_to be_a_directory
@@ -63,7 +63,7 @@ describe Cleaner do
       dir.mkpath
       ln_s dir.basename, symlink
 
-      subject.clean
+      cleaner.clean
 
       expect(dir).not_to exist
       expect(symlink).not_to be_a_symlink
@@ -77,7 +77,7 @@ describe Cleaner do
       dir.mkpath
       ln_s dir.basename, symlink
 
-      subject.clean
+      cleaner.clean
 
       expect(dir).not_to exist
       expect(symlink).not_to be_a_symlink
@@ -88,7 +88,7 @@ describe Cleaner do
       symlink = f.prefix/"symlink"
       ln_s "target", symlink
 
-      subject.clean
+      cleaner.clean
 
       expect(symlink).not_to be_a_symlink
     end
@@ -99,7 +99,7 @@ describe Cleaner do
       f.lib.mkpath
       touch file
 
-      subject.clean
+      cleaner.clean
 
       expect(file).not_to exist
     end
@@ -110,7 +110,7 @@ describe Cleaner do
       (f.lib/"perl5/darwin-thread-multi-2level").mkpath
       touch file
 
-      subject.clean
+      cleaner.clean
 
       expect(file).not_to exist
     end
@@ -121,7 +121,7 @@ describe Cleaner do
       (f.lib/"perl5/darwin-thread-multi-2level/auto/test").mkpath
       touch file
 
-      subject.clean
+      cleaner.clean
 
       expect(file).not_to exist
     end
@@ -132,7 +132,7 @@ describe Cleaner do
       f.lib.mkpath
       touch file
 
-      subject.clean
+      cleaner.clean
 
       expect(file).not_to exist
     end
@@ -143,7 +143,7 @@ describe Cleaner do
       f.class.skip_clean "bin"
       f.bin.mkpath
 
-      subject.clean
+      cleaner.clean
 
       expect(f.bin).to be_a_directory
     end
@@ -153,7 +153,7 @@ describe Cleaner do
       subdir = f.bin/"subdir"
       subdir.mkpath
 
-      subject.clean
+      cleaner.clean
 
       expect(f.bin).to be_a_directory
       expect(subdir).to be_a_directory
@@ -164,7 +164,7 @@ describe Cleaner do
       symlink = f.prefix/"symlink"
       ln_s "target", symlink
 
-      subject.clean
+      cleaner.clean
 
       expect(symlink).to be_a_symlink
     end
@@ -177,7 +177,7 @@ describe Cleaner do
       dir.mkpath
       ln_s dir.basename, symlink
 
-      subject.clean
+      cleaner.clean
 
       expect(dir).not_to exist
       expect(symlink).to be_a_symlink
@@ -192,7 +192,7 @@ describe Cleaner do
       dir.mkpath
       ln_s dir.basename, symlink
 
-      subject.clean
+      cleaner.clean
 
       expect(dir).not_to exist
       expect(symlink).to be_a_symlink
@@ -206,7 +206,7 @@ describe Cleaner do
       f.lib.mkpath
       touch file
 
-      subject.clean
+      cleaner.clean
 
       expect(file).to exist
     end
@@ -217,7 +217,7 @@ describe Cleaner do
 
       dir.mkpath
 
-      subject.clean
+      cleaner.clean
 
       expect(dir).to be_a_directory
     end
@@ -230,7 +230,7 @@ describe Cleaner do
       dir1.mkpath
       dir2.mkpath
 
-      subject.clean
+      cleaner.clean
 
       expect(dir1).to exist
       expect(dir2).not_to exist
diff --git a/Library/Homebrew/test/cleanup_spec.rb b/Library/Homebrew/test/cleanup_spec.rb
index f8c363ad44..a582b007c7 100644
--- a/Library/Homebrew/test/cleanup_spec.rb
+++ b/Library/Homebrew/test/cleanup_spec.rb
@@ -31,6 +31,8 @@ describe Homebrew::Cleanup::CleanupRefinement do
 end
 
 describe Homebrew::Cleanup do
+  subject(:cleanup) { described_class.new }
+
   let(:ds_store) { Pathname.new("#{HOMEBREW_CELLAR}/.DS_Store") }
   let(:lock_file) { Pathname.new("#{HOMEBREW_LOCKS}/foo") }
 
@@ -49,7 +51,7 @@ describe Homebrew::Cleanup do
 
   describe "::cleanup" do
     it "removes .DS_Store and lock files" do
-      subject.clean!
+      cleanup.clean!
 
       expect(ds_store).not_to exist
       expect(lock_file).not_to exist
@@ -65,7 +67,7 @@ describe Homebrew::Cleanup do
     it "doesn't remove the lock file if it is locked" do
       lock_file.open(File::RDWR | File::CREAT).flock(File::LOCK_EX | File::LOCK_NB)
 
-      subject.clean!
+      cleanup.clean!
 
       expect(lock_file).to exist
     end
@@ -89,13 +91,13 @@ describe Homebrew::Cleanup do
       end
 
       it "doesn't remove any kegs" do
-        subject.cleanup_formula f2
+        cleanup.cleanup_formula f2
         expect(f1.installed_kegs.size).to eq(2)
       end
 
       it "lists the unremovable kegs" do
-        subject.cleanup_formula f2
-        expect(subject.unremovable_kegs).to contain_exactly(f1.installed_kegs[0])
+        cleanup.cleanup_formula f2
+        expect(cleanup.unremovable_kegs).to contain_exactly(f1.installed_kegs[0])
       end
     end
   end
@@ -133,7 +135,7 @@ describe Homebrew::Cleanup do
     expect(f3).to be_latest_version_installed
     expect(f4).to be_latest_version_installed
 
-    subject.cleanup_formula f3
+    cleanup.cleanup_formula f3
 
     expect(f1).not_to be_latest_version_installed
     expect(f2).not_to be_latest_version_installed
@@ -154,7 +156,7 @@ describe Homebrew::Cleanup do
 
         FileUtils.touch download
 
-        subject.cleanup_cask(cask)
+        cleanup.cleanup_cask(cask)
 
         expect(download).not_to exist
       end
@@ -164,7 +166,7 @@ describe Homebrew::Cleanup do
 
         FileUtils.touch download
 
-        subject.cleanup_cask(cask)
+        cleanup.cleanup_cask(cask)
 
         expect(download).to exist
       end
@@ -178,7 +180,7 @@ describe Homebrew::Cleanup do
 
         FileUtils.touch download
 
-        subject.cleanup_cask(cask)
+        cleanup.cleanup_cask(cask)
 
         expect(download).to exist
       end
@@ -189,7 +191,7 @@ describe Homebrew::Cleanup do
         allow(download).to receive(:ctime).and_return(30.days.ago - 1.hour)
         allow(download).to receive(:mtime).and_return(30.days.ago - 1.hour)
 
-        subject.cleanup_cask(cask)
+        cleanup.cleanup_cask(cask)
 
         expect(download).not_to exist
       end
@@ -211,14 +213,14 @@ describe Homebrew::Cleanup do
     it "cleans up logs if older than 30 days" do
       allow_any_instance_of(Pathname).to receive(:ctime).and_return(31.days.ago)
       allow_any_instance_of(Pathname).to receive(:mtime).and_return(31.days.ago)
-      subject.cleanup_logs
+      cleanup.cleanup_logs
       expect(path).not_to exist
     end
 
     it "does not clean up logs less than 30 days old" do
       allow_any_instance_of(Pathname).to receive(:ctime).and_return(15.days.ago)
       allow_any_instance_of(Pathname).to receive(:mtime).and_return(15.days.ago)
-      subject.cleanup_logs
+      cleanup.cleanup_logs
       expect(path).to exist
     end
   end
@@ -228,7 +230,7 @@ describe Homebrew::Cleanup do
       incomplete = (HOMEBREW_CACHE/"something.incomplete")
       incomplete.mkpath
 
-      subject.cleanup_cache
+      cleanup.cleanup_cache
 
       expect(incomplete).not_to exist
     end
@@ -237,7 +239,7 @@ describe Homebrew::Cleanup do
       cargo_cache = (HOMEBREW_CACHE/"cargo_cache")
       cargo_cache.mkpath
 
-      subject.cleanup_cache
+      cleanup.cleanup_cache
 
       expect(cargo_cache).not_to exist
     end
@@ -246,7 +248,7 @@ describe Homebrew::Cleanup do
       go_cache = (HOMEBREW_CACHE/"go_cache")
       go_cache.mkpath
 
-      subject.cleanup_cache
+      cleanup.cleanup_cache
 
       expect(go_cache).not_to exist
     end
@@ -255,7 +257,7 @@ describe Homebrew::Cleanup do
       glide_home = (HOMEBREW_CACHE/"glide_home")
       glide_home.mkpath
 
-      subject.cleanup_cache
+      cleanup.cleanup_cache
 
       expect(glide_home).not_to exist
     end
@@ -264,7 +266,7 @@ describe Homebrew::Cleanup do
       java_cache = (HOMEBREW_CACHE/"java_cache")
       java_cache.mkpath
 
-      subject.cleanup_cache
+      cleanup.cleanup_cache
 
       expect(java_cache).not_to exist
     end
@@ -273,7 +275,7 @@ describe Homebrew::Cleanup do
       npm_cache = (HOMEBREW_CACHE/"npm_cache")
       npm_cache.mkpath
 
-      subject.cleanup_cache
+      cleanup.cleanup_cache
 
       expect(npm_cache).not_to exist
     end
@@ -282,7 +284,7 @@ describe Homebrew::Cleanup do
       gclient_cache = (HOMEBREW_CACHE/"gclient_cache")
       gclient_cache.mkpath
 
-      subject.cleanup_cache
+      cleanup.cleanup_cache
 
       expect(gclient_cache).not_to exist
     end
@@ -343,7 +345,7 @@ describe Homebrew::Cleanup do
 
       it "cleans up file if outdated" do
         allow(Utils::Bottles).to receive(:file_outdated?).with(any_args).and_return(true)
-        subject.cleanup_cache
+        cleanup.cleanup_cache
         expect(bottle).not_to exist
         expect(testball).not_to exist
         expect(testball_resource).not_to exist
@@ -357,7 +359,7 @@ describe Homebrew::Cleanup do
       end
 
       it "cleans up file if stale" do
-        subject.cleanup_cache
+        cleanup.cleanup_cache
         expect(bottle).not_to exist
         expect(testball).not_to exist
         expect(testball_resource).not_to exist
diff --git a/Library/Homebrew/test/cmd/info_spec.rb b/Library/Homebrew/test/cmd/info_spec.rb
index 290c0d2cb7..83db3945f0 100644
--- a/Library/Homebrew/test/cmd/info_spec.rb
+++ b/Library/Homebrew/test/cmd/info_spec.rb
@@ -33,16 +33,16 @@ 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"))
+    expect(described_class.github_remote_path(remote, "Formula/git.rb"))
       .to eq("https://github.com/Homebrew/homebrew-core/blob/HEAD/Formula/git.rb")
 
-    expect(subject.github_remote_path("#{remote}.git", "Formula/git.rb"))
+    expect(described_class.github_remote_path("#{remote}.git", "Formula/git.rb"))
       .to eq("https://github.com/Homebrew/homebrew-core/blob/HEAD/Formula/git.rb")
 
-    expect(subject.github_remote_path("git@github.com:user/repo", "foo.rb"))
+    expect(described_class.github_remote_path("git@github.com:user/repo", "foo.rb"))
       .to eq("https://github.com/user/repo/blob/HEAD/foo.rb")
 
-    expect(subject.github_remote_path("https://mywebsite.com", "foo/bar.rb"))
+    expect(described_class.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/compiler_selector_spec.rb b/Library/Homebrew/test/compiler_selector_spec.rb
index a2ab44b943..58017c2b20 100644
--- a/Library/Homebrew/test/compiler_selector_spec.rb
+++ b/Library/Homebrew/test/compiler_selector_spec.rb
@@ -5,7 +5,7 @@ require "compilers"
 require "software_spec"
 
 describe CompilerSelector do
-  subject { described_class.new(software_spec, versions, compilers) }
+  subject(:selector) { described_class.new(software_spec, versions, compilers) }
 
   let(:compilers) { [:clang, :gnu] }
   let(:software_spec) { SoftwareSpec.new }
@@ -29,23 +29,23 @@ describe CompilerSelector do
 
   describe "#compiler" do
     it "defaults to cc" do
-      expect(subject.compiler).to eq(cc)
+      expect(selector.compiler).to eq(cc)
     end
 
     it "returns clang if it fails with non-Apple gcc" do
       software_spec.fails_with(gcc: "7")
-      expect(subject.compiler).to eq(:clang)
+      expect(selector.compiler).to eq(:clang)
     end
 
     it "still returns gcc-7 if it fails with gcc without a specific version" do
       software_spec.fails_with(:clang)
-      expect(subject.compiler).to eq("gcc-7")
+      expect(selector.compiler).to eq("gcc-7")
     end
 
     it "returns gcc-6 if gcc formula offers gcc-6" do
       software_spec.fails_with(:clang)
       allow(Formulary).to receive(:factory).with("gcc").and_return(double(version: "6.0"))
-      expect(subject.compiler).to eq("gcc-6")
+      expect(selector.compiler).to eq("gcc-6")
     end
 
     it "raises an error when gcc or llvm is missing" do
@@ -53,7 +53,7 @@ describe CompilerSelector do
       software_spec.fails_with(gcc: "7")
       software_spec.fails_with(gcc: "6")
 
-      expect { subject.compiler }.to raise_error(CompilerSelectionError)
+      expect { selector.compiler }.to raise_error(CompilerSelectionError)
     end
   end
 end
diff --git a/Library/Homebrew/test/dependable_spec.rb b/Library/Homebrew/test/dependable_spec.rb
index 61b153a3e9..12fabd6f3e 100644
--- a/Library/Homebrew/test/dependable_spec.rb
+++ b/Library/Homebrew/test/dependable_spec.rb
@@ -6,23 +6,23 @@ require "dependable"
 describe Dependable do
   alias_matcher :be_a_build_dependency, :be_build
 
-  subject { double(tags: tags).extend(described_class) }
+  subject(:dependable) { double(tags: tags).extend(described_class) }
 
   let(:tags) { ["foo", "bar", :build] }
 
   specify "#options" do
-    expect(subject.options.as_flags.sort).to eq(%w[--foo --bar].sort)
+    expect(dependable.options.as_flags.sort).to eq(%w[--foo --bar].sort)
   end
 
   specify "#build?" do
-    expect(subject).to be_a_build_dependency
+    expect(dependable).to be_a_build_dependency
   end
 
   specify "#optional?" do
-    expect(subject).not_to be_optional
+    expect(dependable).not_to be_optional
   end
 
   specify "#recommended?" do
-    expect(subject).not_to be_recommended
+    expect(dependable).not_to be_recommended
   end
 end
diff --git a/Library/Homebrew/test/dependencies_spec.rb b/Library/Homebrew/test/dependencies_spec.rb
index b9b5ae7c60..23119824fa 100644
--- a/Library/Homebrew/test/dependencies_spec.rb
+++ b/Library/Homebrew/test/dependencies_spec.rb
@@ -5,40 +5,42 @@ require "dependencies"
 require "dependency"
 
 describe Dependencies do
+  subject(:dependencies) { described_class.new }
+
   describe "#<<" do
     it "returns itself" do
-      expect(subject << Dependency.new("foo")).to eq(subject)
+      expect(dependencies << Dependency.new("foo")).to eq(dependencies)
     end
 
     it "preserves order" do
       hash = { 0 => "foo", 1 => "bar", 2 => "baz" }
 
-      subject << Dependency.new(hash[0])
-      subject << Dependency.new(hash[1])
-      subject << Dependency.new(hash[2])
+      dependencies << Dependency.new(hash[0])
+      dependencies << Dependency.new(hash[1])
+      dependencies << Dependency.new(hash[2])
 
-      subject.each_with_index do |dep, i|
+      dependencies.each_with_index do |dep, i|
         expect(dep.name).to eq(hash[i])
       end
     end
   end
 
   specify "#*" do
-    subject << Dependency.new("foo")
-    subject << Dependency.new("bar")
-    expect(subject * ", ").to eq("foo, bar")
+    dependencies << Dependency.new("foo")
+    dependencies << Dependency.new("bar")
+    expect(dependencies * ", ").to eq("foo, bar")
   end
 
   specify "#to_a" do
     dep = Dependency.new("foo")
-    subject << dep
-    expect(subject.to_a).to eq([dep])
+    dependencies << dep
+    expect(dependencies.to_a).to eq([dep])
   end
 
   specify "#to_ary" do
     dep = Dependency.new("foo")
-    subject << dep
-    expect(subject.to_ary).to eq([dep])
+    dependencies << dep
+    expect(dependencies.to_ary).to eq([dep])
   end
 
   specify "type helpers" do
@@ -47,12 +49,12 @@ describe Dependencies do
     baz = Dependency.new("baz", [:build])
     qux = Dependency.new("qux", [:recommended])
     quux = Dependency.new("quux")
-    subject << foo << bar << baz << qux << quux
-    expect(subject.required).to eq([foo, quux])
-    expect(subject.optional).to eq([bar])
-    expect(subject.build).to eq([baz])
-    expect(subject.recommended).to eq([qux])
-    expect(subject.default.sort_by(&:name)).to eq([foo, baz, quux, qux].sort_by(&:name))
+    dependencies << foo << bar << baz << qux << quux
+    expect(dependencies.required).to eq([foo, quux])
+    expect(dependencies.optional).to eq([bar])
+    expect(dependencies.build).to eq([baz])
+    expect(dependencies.recommended).to eq([qux])
+    expect(dependencies.default.sort_by(&:name)).to eq([foo, baz, quux, qux].sort_by(&:name))
   end
 
   specify "equality" do
@@ -74,16 +76,16 @@ describe Dependencies do
   end
 
   specify "#empty?" do
-    expect(subject).to be_empty
+    expect(dependencies).to be_empty
 
-    subject << Dependency.new("foo")
-    expect(subject).not_to be_empty
+    dependencies << Dependency.new("foo")
+    expect(dependencies).not_to be_empty
   end
 
   specify "#inspect" do
-    expect(subject.inspect).to eq("#<Dependencies: []>")
+    expect(dependencies.inspect).to eq("#<Dependencies: []>")
 
-    subject << Dependency.new("foo")
-    expect(subject.inspect).to eq("#<Dependencies: [#<Dependency: \"foo\" []>]>")
+    dependencies << Dependency.new("foo")
+    expect(dependencies.inspect).to eq("#<Dependencies: [#<Dependency: \"foo\" []>]>")
   end
 end
diff --git a/Library/Homebrew/test/dependency_collector_spec.rb b/Library/Homebrew/test/dependency_collector_spec.rb
index 80e187dfc9..bff6a44f41 100644
--- a/Library/Homebrew/test/dependency_collector_spec.rb
+++ b/Library/Homebrew/test/dependency_collector_spec.rb
@@ -6,102 +6,104 @@ require "dependency_collector"
 describe DependencyCollector do
   alias_matcher :be_a_build_requirement, :be_build
 
+  subject(:collector) { described_class.new }
+
   def find_dependency(name)
-    subject.deps.find { |dep| dep.name == name }
+    collector.deps.find { |dep| dep.name == name }
   end
 
   def find_requirement(klass)
-    subject.requirements.find { |req| req.is_a? klass }
+    collector.requirements.find { |req| req.is_a? klass }
   end
 
   describe "#add" do
     specify "dependency creation" do
-      subject.add "foo" => :build
-      subject.add "bar" => ["--universal", :optional]
+      collector.add "foo" => :build
+      collector.add "bar" => ["--universal", :optional]
       expect(find_dependency("foo")).to be_an_instance_of(Dependency)
       expect(find_dependency("bar").tags.count).to eq(2)
     end
 
     it "returns the created dependency" do
-      expect(subject.add("foo")).to eq(Dependency.new("foo"))
+      expect(collector.add("foo")).to eq(Dependency.new("foo"))
     end
 
     specify "requirement creation" do
-      subject.add :xcode
+      collector.add :xcode
       expect(find_requirement(XcodeRequirement)).to be_an_instance_of(XcodeRequirement)
     end
 
     it "deduplicates requirements" do
-      2.times { subject.add :xcode }
-      expect(subject.requirements.count).to eq(1)
+      2.times { collector.add :xcode }
+      expect(collector.requirements.count).to eq(1)
     end
 
     specify "requirement tags" do
-      subject.add xcode: :build
+      collector.add xcode: :build
       expect(find_requirement(XcodeRequirement)).to be_a_build_requirement
     end
 
     it "doesn't mutate the dependency spec" do
       spec = { "foo" => :optional }
       copy = spec.dup
-      subject.add(spec)
+      collector.add(spec)
       expect(spec).to eq(copy)
     end
 
     it "creates a resource dependency from a CVS URL" do
       resource = Resource.new
       resource.url(":pserver:anonymous:@brew.sh:/cvsroot/foo/bar", using: :cvs)
-      expect(subject.add(resource)).to eq(Dependency.new("cvs", [:build, :test]))
+      expect(collector.add(resource)).to eq(Dependency.new("cvs", [:build, :test]))
     end
 
     it "creates a resource dependency from a '.7z' URL" do
       resource = Resource.new
       resource.url("https://brew.sh/foo.7z")
-      expect(subject.add(resource)).to eq(Dependency.new("p7zip", [:build, :test]))
+      expect(collector.add(resource)).to eq(Dependency.new("p7zip", [:build, :test]))
     end
 
     it "creates a resource dependency from a '.gz' URL" do
       resource = Resource.new
       resource.url("https://brew.sh/foo.tar.gz")
-      expect(subject.add(resource)).to be nil
+      expect(collector.add(resource)).to be nil
     end
 
     it "creates a resource dependency from a '.lz' URL" do
       resource = Resource.new
       resource.url("https://brew.sh/foo.lz")
-      expect(subject.add(resource)).to eq(Dependency.new("lzip", [:build, :test]))
+      expect(collector.add(resource)).to eq(Dependency.new("lzip", [:build, :test]))
     end
 
     it "creates a resource dependency from a '.lha' URL" do
       resource = Resource.new
       resource.url("https://brew.sh/foo.lha")
-      expect(subject.add(resource)).to eq(Dependency.new("lha", [:build, :test]))
+      expect(collector.add(resource)).to eq(Dependency.new("lha", [:build, :test]))
     end
 
     it "creates a resource dependency from a '.lzh' URL" do
       resource = Resource.new
       resource.url("https://brew.sh/foo.lzh")
-      expect(subject.add(resource)).to eq(Dependency.new("lha", [:build, :test]))
+      expect(collector.add(resource)).to eq(Dependency.new("lha", [:build, :test]))
     end
 
     it "creates a resource dependency from a '.rar' URL" do
       resource = Resource.new
       resource.url("https://brew.sh/foo.rar")
-      expect(subject.add(resource)).to eq(Dependency.new("unrar", [:build, :test]))
+      expect(collector.add(resource)).to eq(Dependency.new("unrar", [:build, :test]))
     end
 
     it "raises a TypeError for unknown classes" do
-      expect { subject.add(Class.new) }.to raise_error(TypeError)
+      expect { collector.add(Class.new) }.to raise_error(TypeError)
     end
 
     it "raises a TypeError for unknown Types" do
-      expect { subject.add(Object.new) }.to raise_error(TypeError)
+      expect { collector.add(Object.new) }.to raise_error(TypeError)
     end
 
     it "raises a TypeError for a Resource with an unknown download strategy" do
       resource = Resource.new
       resource.download_strategy = Class.new
-      expect { subject.add(resource) }.to raise_error(TypeError)
+      expect { collector.add(resource) }.to raise_error(TypeError)
     end
   end
 end
diff --git a/Library/Homebrew/test/dependency_spec.rb b/Library/Homebrew/test/dependency_spec.rb
index 3c606c86ca..dea2c83982 100644
--- a/Library/Homebrew/test/dependency_spec.rb
+++ b/Library/Homebrew/test/dependency_spec.rb
@@ -103,13 +103,13 @@ describe Dependency do
 end
 
 describe TapDependency do
-  subject { described_class.new("foo/bar/dog") }
+  subject(:dependency) { described_class.new("foo/bar/dog") }
 
   specify "#tap" do
-    expect(subject.tap).to eq(Tap.new("foo", "bar"))
+    expect(dependency.tap).to eq(Tap.new("foo", "bar"))
   end
 
   specify "#option_names" do
-    expect(subject.option_names).to eq(%w[dog])
+    expect(dependency.option_names).to eq(%w[dog])
   end
 end
diff --git a/Library/Homebrew/test/descriptions_spec.rb b/Library/Homebrew/test/descriptions_spec.rb
index e1afb7ec8e..f36dfe2fef 100644
--- a/Library/Homebrew/test/descriptions_spec.rb
+++ b/Library/Homebrew/test/descriptions_spec.rb
@@ -4,25 +4,25 @@
 require "descriptions"
 
 describe Descriptions do
-  subject { described_class.new(descriptions_hash) }
+  subject(:descriptions) { 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
+    expect { descriptions.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
+    expect { descriptions.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(
+    expect { descriptions.print }.to output(
       <<~EOS,
         homebrew/core/foo: Core foo
         somedev/external/foo: External foo
@@ -35,7 +35,7 @@ describe Descriptions do
     descriptions_hash["somedev/external/foo"] = "External foo"
     descriptions_hash["otherdev/external/foo"] = "Other external foo"
 
-    expect { subject.print }.to output(
+    expect { descriptions.print }.to output(
       <<~EOS,
         homebrew/core/foo: Core foo
         otherdev/external/foo: Other external foo
diff --git a/Library/Homebrew/test/diagnostic_checks_spec.rb b/Library/Homebrew/test/diagnostic_checks_spec.rb
index e62e6af20a..f1d8578dfe 100644
--- a/Library/Homebrew/test/diagnostic_checks_spec.rb
+++ b/Library/Homebrew/test/diagnostic_checks_spec.rb
@@ -4,9 +4,11 @@
 require "diagnostic"
 
 describe Homebrew::Diagnostic::Checks do
+  subject(:checks) { described_class.new }
+
   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")
+    expect(checks.inject_file_list([], "foo:\n")).to eq("foo:\n")
+    expect(checks.inject_file_list(%w[/a /b], "foo:\n")).to eq("foo:\n  /a\n  /b\n")
   end
 
   specify "#check_for_anaconda" do
@@ -22,7 +24,7 @@ describe Homebrew::Diagnostic::Checks do
 
       ENV["PATH"] = "#{path}#{File::PATH_SEPARATOR}#{ENV["PATH"]}"
 
-      expect(subject.check_for_anaconda).to match("Anaconda")
+      expect(checks.check_for_anaconda).to match("Anaconda")
     end
   end
 
@@ -40,7 +42,7 @@ describe Homebrew::Diagnostic::Checks do
       dirs.each do |dir|
         modes[dir] = dir.stat.mode & 0777
         dir.chmod 0555
-        expect(subject.check_access_directories).to match(dir.to_s)
+        expect(checks.check_access_directories).to match(dir.to_s)
       end
     ensure
       modes.each do |dir, mode|
@@ -60,7 +62,7 @@ describe Homebrew::Diagnostic::Checks do
     # HOMEBREW_PREFIX/bin/
     (bin/File.basename(Dir["/usr/bin/*"].first)).mkpath
 
-    expect(subject.check_user_path_1)
+    expect(checks.check_user_path_1)
       .to match("/usr/bin occurs before #{HOMEBREW_PREFIX}/bin")
   end
 
@@ -68,8 +70,8 @@ describe Homebrew::Diagnostic::Checks do
     ENV["PATH"] = ENV["PATH"].gsub \
       %r{(?:^|#{File::PATH_SEPARATOR})#{HOMEBREW_PREFIX}/bin}o, ""
 
-    expect(subject.check_user_path_1).to be nil
-    expect(subject.check_user_path_2)
+    expect(checks.check_user_path_1).to be nil
+    expect(checks.check_user_path_2)
       .to match("Homebrew's \"bin\" was not found in your PATH.")
   end
 
@@ -80,9 +82,9 @@ describe Homebrew::Diagnostic::Checks do
       ENV["HOMEBREW_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)
+    expect(checks.check_user_path_1).to be nil
+    expect(checks.check_user_path_2).to be nil
+    expect(checks.check_user_path_3)
       .to match("Homebrew's \"sbin\" was not found in your PATH")
   ensure
     sbin.rmtree
@@ -96,7 +98,7 @@ describe Homebrew::Diagnostic::Checks do
       ENV["HOMEBREW_PATH"] = ENV["PATH"] =
         "#{path}#{File::PATH_SEPARATOR}#{ENV["PATH"]}"
 
-      expect(subject.check_for_config_scripts)
+      expect(checks.check_for_config_scripts)
         .to match('"config" scripts exist')
     end
   end
@@ -107,7 +109,7 @@ describe Homebrew::Diagnostic::Checks do
     mktmpdir do |path|
       FileUtils.ln_s path, HOMEBREW_CELLAR
 
-      expect(subject.check_for_symlinked_cellar).to match(path)
+      expect(checks.check_for_symlinked_cellar).to match(path)
     end
   ensure
     HOMEBREW_CELLAR.unlink
@@ -116,7 +118,7 @@ describe Homebrew::Diagnostic::Checks do
 
   specify "#check_tmpdir" do
     ENV["TMPDIR"] = "/i/don/t/exis/t"
-    expect(subject.check_tmpdir).to match("doesn't exist")
+    expect(checks.check_tmpdir).to match("doesn't exist")
   end
 
   specify "#check_for_external_cmd_name_conflict" do
@@ -130,7 +132,7 @@ describe Homebrew::Diagnostic::Checks do
 
         allow(Tap).to receive(:cmd_directories).and_return([path1, path2])
 
-        expect(subject.check_for_external_cmd_name_conflict)
+        expect(checks.check_for_external_cmd_name_conflict)
           .to match("brew-foo")
       end
     end
@@ -138,7 +140,7 @@ describe Homebrew::Diagnostic::Checks do
 
   specify "#check_homebrew_prefix" do
     allow(Homebrew).to receive(:default_prefix?).and_return(false)
-    expect(subject.check_homebrew_prefix)
+    expect(checks.check_homebrew_prefix)
       .to match("Your Homebrew's prefix is not #{Homebrew::DEFAULT_PREFIX}")
   end
 end
diff --git a/Library/Homebrew/test/download_strategies_spec.rb b/Library/Homebrew/test/download_strategies_spec.rb
index 0a59c06e03..5d1a20603d 100644
--- a/Library/Homebrew/test/download_strategies_spec.rb
+++ b/Library/Homebrew/test/download_strategies_spec.rb
@@ -4,7 +4,7 @@
 require "download_strategy"
 
 describe AbstractDownloadStrategy do
-  subject { described_class.new(url, name, version, **specs) }
+  subject(:strategy) { described_class.new(url, name, version, **specs) }
 
   let(:specs) { {} }
   let(:name) { "foo" }
@@ -17,7 +17,7 @@ describe AbstractDownloadStrategy 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"))
+      expect(strategy.source_modified_time).to eq(File.mtime("foo"))
     end
   end
 
@@ -25,13 +25,13 @@ describe AbstractDownloadStrategy do
     let(:specs) { { bottle: true } }
 
     it "extends Pourable" do
-      expect(subject).to be_a_kind_of(AbstractDownloadStrategy::Pourable)
+      expect(strategy).to be_a_kind_of(AbstractDownloadStrategy::Pourable)
     end
   end
 
   context "without specs[:bottle]" do
     it "is does not extend Pourable" do
-      expect(subject).not_to be_a_kind_of(AbstractDownloadStrategy::Pourable)
+      expect(strategy).not_to be_a_kind_of(AbstractDownloadStrategy::Pourable)
     end
   end
 end
@@ -50,20 +50,20 @@ describe VCSDownloadStrategy do
 end
 
 describe GitHubGitDownloadStrategy do
-  subject { described_class.new(url, name, version) }
+  subject(:strategy) { described_class.new(url, name, version) }
 
   let(:name) { "brew" }
   let(:url) { "https://github.com/homebrew/brew.git" }
   let(: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")
+    expect(strategy.instance_variable_get(:@user)).to eq("homebrew")
+    expect(strategy.instance_variable_get(:@repo)).to eq("brew")
   end
 end
 
 describe GitDownloadStrategy do
-  subject { described_class.new(url, name, version) }
+  subject(:strategy) { described_class.new(url, name, version) }
 
   let(:name) { "baz" }
   let(:url) { "https://github.com/homebrew/foo" }
@@ -93,7 +93,7 @@ describe GitDownloadStrategy do
       cached_location.cd do
         setup_git_repo
       end
-      expect(subject.source_modified_time.to_i).to eq(1_485_115_153)
+      expect(strategy.source_modified_time.to_i).to eq(1_485_115_153)
     end
   end
 
@@ -103,7 +103,7 @@ describe GitDownloadStrategy do
       FileUtils.touch "LICENSE"
       git_commit_all
     end
-    expect(subject.last_commit).to eq("f68266e")
+    expect(strategy.last_commit).to eq("f68266e")
   end
 
   describe "#fetch_last_commit" do
@@ -122,13 +122,13 @@ describe GitDownloadStrategy do
         git_commit_all
       end
 
-      expect(subject.fetch_last_commit).to eq("f68266e")
+      expect(strategy.fetch_last_commit).to eq("f68266e")
     end
   end
 end
 
 describe CurlDownloadStrategy do
-  subject { described_class.new(url, name, version, **specs) }
+  subject(:strategy) { described_class.new(url, name, version, **specs) }
 
   let(:name) { "foo" }
   let(:url) { "https://example.com/foo.tar.gz" }
@@ -136,15 +136,15 @@ describe CurlDownloadStrategy do
   let(:specs) { { user: "download:123456" } }
 
   it "parses the opts and sets the corresponding args" do
-    expect(subject.send(:_curl_args)).to eq(["--user", "download:123456"])
+    expect(strategy.send(:_curl_args)).to eq(["--user", "download:123456"])
   end
 
   describe "#cached_location" do
-    subject { described_class.new(url, name, version, **specs).cached_location }
+    subject(:location) { described_class.new(url, name, version, **specs).cached_location }
 
     context "when URL ends with file" do
       it {
-        expect(subject).to eq(
+        expect(location).to eq(
           HOMEBREW_CACHE/"downloads/3d1c0ae7da22be9d83fb1eb774df96b7c4da71d3cf07e1cb28555cf9a5e5af70--foo.tar.gz",
         )
       }
@@ -154,7 +154,7 @@ describe CurlDownloadStrategy do
       let(:url) { "https://example.com/foo.tar.gz/from/this/mirror" }
 
       it {
-        expect(subject).to eq(
+        expect(location).to eq(
           HOMEBREW_CACHE/"downloads/1ab61269ba52c83994510b1e28dd04167a2f2e8393a35a9c50c1f7d33fd8f619--foo.tar.gz",
         )
       }
@@ -163,12 +163,12 @@ describe CurlDownloadStrategy do
 
   describe "#fetch" do
     before do
-      subject.temporary_path.dirname.mkpath
-      FileUtils.touch subject.temporary_path
+      strategy.temporary_path.dirname.mkpath
+      FileUtils.touch strategy.temporary_path
     end
 
     it "calls curl with default arguments" do
-      expect(subject).to receive(:curl).with(
+      expect(strategy).to receive(:curl).with(
         "--location",
         "--remote-time",
         "--continue-at", "0",
@@ -177,21 +177,21 @@ describe CurlDownloadStrategy do
         an_instance_of(Hash)
       )
 
-      subject.fetch
+      strategy.fetch
     end
 
     context "with an explicit user agent" do
       let(:specs) { { user_agent: "Mozilla/25.0.1" } }
 
       it "adds the appropriate curl args" do
-        expect(subject).to receive(:system_command).with(
+        expect(strategy).to receive(:system_command).with(
           /curl/,
           hash_including(args: array_including_cons("--user-agent", "Mozilla/25.0.1")),
         )
         .at_least(:once)
         .and_return(instance_double(SystemCommand::Result, success?: true, stdout: "", assert_success!: nil))
 
-        subject.fetch
+        strategy.fetch
       end
     end
 
@@ -201,7 +201,7 @@ describe CurlDownloadStrategy do
       let(:specs) { { user_agent: :fake } }
 
       it "adds the appropriate curl args" do
-        expect(subject).to receive(:system_command).with(
+        expect(strategy).to receive(:system_command).with(
           /curl/,
           hash_including(args: array_including_cons(
             "--user-agent",
@@ -211,7 +211,7 @@ describe CurlDownloadStrategy do
         .at_least(:once)
         .and_return(instance_double(SystemCommand::Result, success?: true, stdout: "", assert_success!: nil))
 
-        subject.fetch
+        strategy.fetch
       end
     end
 
@@ -226,14 +226,14 @@ describe CurlDownloadStrategy do
       }
 
       it "adds the appropriate curl args and does not URL-encode the cookies" do
-        expect(subject).to receive(:system_command).with(
+        expect(strategy).to receive(:system_command).with(
           /curl/,
           hash_including(args: array_including_cons("-b", "coo=k/e;mon=ster")),
         )
         .at_least(:once)
         .and_return(instance_double(SystemCommand::Result, success?: true, stdout: "", assert_success!: nil))
 
-        subject.fetch
+        strategy.fetch
       end
     end
 
@@ -241,14 +241,14 @@ describe CurlDownloadStrategy do
       let(:specs) { { referer: "https://somehost/also" } }
 
       it "adds the appropriate curl args" do
-        expect(subject).to receive(:system_command).with(
+        expect(strategy).to receive(:system_command).with(
           /curl/,
           hash_including(args: array_including_cons("-e", "https://somehost/also")),
         )
         .at_least(:once)
         .and_return(instance_double(SystemCommand::Result, success?: true, stdout: "", assert_success!: nil))
 
-        subject.fetch
+        strategy.fetch
       end
     end
 
@@ -258,14 +258,14 @@ describe CurlDownloadStrategy do
       let(:specs) { { headers: ["foo", "bar"] } }
 
       it "adds the appropriate curl args" do
-        expect(subject).to receive(:system_command).with(
+        expect(strategy).to receive(:system_command).with(
           /curl/,
           hash_including(args: array_including_cons("--header", "foo").and(array_including_cons("--header", "bar"))),
         )
         .at_least(:once)
         .and_return(instance_double(SystemCommand::Result, success?: true, stdout: "", assert_success!: nil))
 
-        subject.fetch
+        strategy.fetch
       end
     end
   end
@@ -315,7 +315,7 @@ describe CurlDownloadStrategy do
 end
 
 describe CurlPostDownloadStrategy do
-  subject { described_class.new(url, name, version, **specs) }
+  subject(:strategy) { described_class.new(url, name, version, **specs) }
 
   let(:name) { "foo" }
   let(:url) { "https://example.com/foo.tar.gz" }
@@ -324,8 +324,8 @@ describe CurlPostDownloadStrategy do
 
   describe "#fetch" do
     before do
-      subject.temporary_path.dirname.mkpath
-      FileUtils.touch subject.temporary_path
+      strategy.temporary_path.dirname.mkpath
+      FileUtils.touch strategy.temporary_path
     end
 
     context "with :using and :data specified" do
@@ -340,14 +340,14 @@ describe CurlPostDownloadStrategy do
       }
 
       it "adds the appropriate curl args" do
-        expect(subject).to receive(:system_command).with(
+        expect(strategy).to receive(:system_command).with(
           /curl/,
           hash_including(args: array_including_cons("-d", "form=data").and(array_including_cons("-d", "is=good"))),
         )
         .at_least(:once)
         .and_return(instance_double(SystemCommand::Result, success?: true, stdout: "", assert_success!: nil))
 
-        subject.fetch
+        strategy.fetch
       end
     end
 
@@ -355,21 +355,21 @@ describe CurlPostDownloadStrategy do
       let(:specs) { { using: :post } }
 
       it "adds the appropriate curl args" do
-        expect(subject).to receive(:system_command).with(
+        expect(strategy).to receive(:system_command).with(
           /curl/,
           hash_including(args: array_including_cons("-X", "POST")),
         )
         .at_least(:once)
         .and_return(instance_double(SystemCommand::Result, success?: true, stdout: "", assert_success!: nil))
 
-        subject.fetch
+        strategy.fetch
       end
     end
   end
 end
 
 describe SubversionDownloadStrategy do
-  subject { described_class.new(url, name, version, **specs) }
+  subject(:strategy) { described_class.new(url, name, version, **specs) }
 
   let(:name) { "foo" }
   let(:url) { "https://example.com/foo.tar.gz" }
@@ -381,9 +381,9 @@ describe SubversionDownloadStrategy do
       let(:specs) { { trust_cert: true } }
 
       it "adds the appropriate svn args" do
-        expect(subject).to receive(:system_command!)
+        expect(strategy).to receive(:system_command!)
           .with("svn", hash_including(args: array_including("--trust-server-cert", "--non-interactive")))
-        subject.fetch
+        strategy.fetch
       end
     end
 
@@ -391,10 +391,10 @@ describe SubversionDownloadStrategy do
       let(:specs) { { revision: "10" } }
 
       it "adds svn arguments for :revision" do
-        expect(subject).to receive(:system_command!)
+        expect(strategy).to receive(:system_command!)
           .with("svn", hash_including(args: array_including_cons("-r", "10")))
 
-        subject.fetch
+        strategy.fetch
       end
     end
   end
@@ -402,7 +402,7 @@ end
 
 describe DownloadStrategyDetector do
   describe "::detect" do
-    subject { described_class.detect(url, strategy) }
+    subject(:strategy_detector) { described_class.detect(url, strategy) }
 
     let(:url) { Object.new }
     let(:strategy) { nil }
@@ -420,7 +420,7 @@ describe DownloadStrategyDetector do
     end
 
     it "defaults to curl" do
-      expect(subject).to eq(CurlDownloadStrategy)
+      expect(strategy_detector).to eq(CurlDownloadStrategy)
     end
 
     it "raises an error when passed an unrecognized strategy" do
diff --git a/Library/Homebrew/test/error_during_execution_spec.rb b/Library/Homebrew/test/error_during_execution_spec.rb
index 2b91937619..a3f6221198 100644
--- a/Library/Homebrew/test/error_during_execution_spec.rb
+++ b/Library/Homebrew/test/error_during_execution_spec.rb
@@ -47,7 +47,7 @@ describe ErrorDuringExecution do
       end
 
       its(:to_s) {
-        expect(subject.to_s).to eq <<~EOS
+        expect(error.to_s).to eq <<~EOS
           Failure while executing; `false` exited with 1. Here's the output:
           This still worked.
           #{Formatter.error("Here something went wrong.\n")}
@@ -59,7 +59,7 @@ describe ErrorDuringExecution do
       let(:command) { ["env", "PATH=/bin", "cat", "with spaces"] }
 
       its(:to_s) {
-        expect(subject.to_s)
+        expect(error.to_s)
           .to eq 'Failure while executing; `env PATH=/bin cat with\ spaces` exited with 1.'
       }
     end
diff --git a/Library/Homebrew/test/exceptions_spec.rb b/Library/Homebrew/test/exceptions_spec.rb
index aaf8b54f08..87b3f44dd2 100644
--- a/Library/Homebrew/test/exceptions_spec.rb
+++ b/Library/Homebrew/test/exceptions_spec.rb
@@ -26,29 +26,29 @@ describe NoSuchKegError do
 end
 
 describe FormulaValidationError do
-  subject { described_class.new("foo", "sha257", "magic") }
+  subject(:error) { described_class.new("foo", "sha257", "magic") }
 
   its(:to_s) {
-    expect(subject.to_s).to eq(%q(invalid attribute for formula 'foo': sha257 ("magic")))
+    expect(error.to_s).to eq(%q(invalid attribute for formula 'foo': sha257 ("magic")))
   }
 end
 
 describe FormulaUnavailableError do
-  subject { described_class.new("foo") }
+  subject(:error) { described_class.new("foo") }
 
   describe "#dependent_s" do
     it "returns nil if there is no dependent" do
-      expect(subject.dependent_s).to be nil
+      expect(error.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
+      error.dependent = "foo"
+      expect(error.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)")
+      error.dependent = "foobar"
+      expect(error.dependent_s).to eq(" (dependency of foobar)")
     end
   end
 
@@ -58,11 +58,11 @@ describe FormulaUnavailableError do
 
   context "with a dependent" do
     before do
-      subject.dependent = "foobar"
+      error.dependent = "foobar"
     end
 
     its(:to_s) {
-      expect(subject.to_s).to eq('No available formula with the name "foo" (dependency of foobar).')
+      expect(error.to_s).to eq('No available formula with the name "foo" (dependency of foobar).')
     }
   end
 end
@@ -76,7 +76,7 @@ describe TapFormulaUnavailableError do
 end
 
 describe FormulaClassUnavailableError do
-  subject { described_class.new("foo", "foo.rb", "Foo", list) }
+  subject(:error) { described_class.new("foo", "foo.rb", "Foo", list) }
 
   let(:mod) do
     Module.new do
@@ -90,7 +90,7 @@ describe FormulaClassUnavailableError do
     let(:list) { [] }
 
     its(:to_s) {
-      expect(subject.to_s).to match(/Expected to find class Foo, but found no classes\./)
+      expect(error.to_s).to match(/Expected to find class Foo, but found no classes\./)
     }
   end
 
@@ -98,7 +98,7 @@ describe FormulaClassUnavailableError do
     let(:list) { [mod.const_get(:Bar)] }
 
     its(:to_s) {
-      expect(subject.to_s).to match(/Expected to find class Foo, but only found: Bar \(not derived from Formula!\)\./)
+      expect(error.to_s).to match(/Expected to find class Foo, but only found: Bar \(not derived from Formula!\)\./)
     }
   end
 
diff --git a/Library/Homebrew/test/formatter_spec.rb b/Library/Homebrew/test/formatter_spec.rb
index 9e8d214f70..95e87ea486 100644
--- a/Library/Homebrew/test/formatter_spec.rb
+++ b/Library/Homebrew/test/formatter_spec.rb
@@ -6,7 +6,7 @@ require "utils/tty"
 
 describe Formatter do
   describe "::columns" do
-    subject { described_class.columns(input) }
+    subject(:columns) { described_class.columns(input) }
 
     let(:input) {
       %w[
@@ -21,7 +21,7 @@ describe Formatter do
       allow_any_instance_of(IO).to receive(:tty?).and_return(false)
       allow(Tty).to receive(:width).and_return(10)
 
-      expect(subject).to eq(
+      expect(columns).to eq(
         "aa\n" \
         "bbb\n" \
         "ccc\n" \
@@ -34,7 +34,7 @@ describe Formatter do
         allow_any_instance_of(IO).to receive(:tty?).and_return(true)
         allow(Tty).to receive(:width).and_return(10)
 
-        expect(subject).to eq(
+        expect(columns).to eq(
           "aa    ccc\n" \
           "bbb   dd\n",
         )
@@ -44,7 +44,7 @@ describe Formatter do
         allow_any_instance_of(IO).to receive(:tty?).and_return(true)
         allow(Tty).to receive(:width).and_return(20)
 
-        expect(subject).to eq(
+        expect(columns).to eq(
           "aa   bbb  ccc  dd\n",
         )
       end
diff --git a/Library/Homebrew/test/formula_pin_spec.rb b/Library/Homebrew/test/formula_pin_spec.rb
index 04e371cb47..e694ac875c 100644
--- a/Library/Homebrew/test/formula_pin_spec.rb
+++ b/Library/Homebrew/test/formula_pin_spec.rb
@@ -4,7 +4,7 @@
 require "formula_pin"
 
 describe FormulaPin do
-  subject { described_class.new(formula) }
+  subject(:formula_pin) { described_class.new(formula) }
 
   let(:name) { "double" }
   let(:formula) { double(Formula, name: name, rack: HOMEBREW_CELLAR/name) }
@@ -22,24 +22,24 @@ describe FormulaPin do
   end
 
   it "is not pinnable by default" do
-    expect(subject).not_to be_pinnable
+    expect(formula_pin).not_to be_pinnable
   end
 
   it "is pinnable if the Keg exists" do
     (formula.rack/"0.1").mkpath
-    expect(subject).to be_pinnable
+    expect(formula_pin).to be_pinnable
   end
 
   specify "#pin and #unpin" do
     (formula.rack/"0.1").mkpath
 
-    subject.pin
-    expect(subject).to be_pinned
+    formula_pin.pin
+    expect(formula_pin).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
+    formula_pin.unpin
+    expect(formula_pin).not_to be_pinned
     expect(HOMEBREW_PINNED_KEGS).not_to be_a_directory
   end
 end
diff --git a/Library/Homebrew/test/language/node_spec.rb b/Library/Homebrew/test/language/node_spec.rb
index 44ce3faad1..5202296e40 100644
--- a/Library/Homebrew/test/language/node_spec.rb
+++ b/Library/Homebrew/test/language/node_spec.rb
@@ -13,16 +13,16 @@ describe Language::Node do
       end
       stub_formula_loader(node)
       expect(ENV).to receive(:prepend_path)
-      subject.instance_variable_set(:@env_set, false)
-      expect(subject.setup_npm_environment).to be_nil
+      described_class.instance_variable_set(:@env_set, false)
+      expect(described_class.setup_npm_environment).to be_nil
 
-      expect(subject.instance_variable_get(:@env_set)).to eq(true)
+      expect(described_class.instance_variable_get(:@env_set)).to eq(true)
       expect(ENV).not_to receive(:prepend_path)
-      expect(subject.setup_npm_environment).to be_nil
+      expect(described_class.setup_npm_environment).to be_nil
     end
 
     it "does not call prepend_path when node formula does not exist" do
-      expect(subject.setup_npm_environment).to be_nil
+      expect(described_class.setup_npm_environment).to be_nil
     end
   end
 
@@ -32,7 +32,7 @@ describe Language::Node do
         path = Pathname("package.json")
         path.atomic_write("{\"scripts\":{\"prepare\": \"ls\", \"prepack\": \"ls\", \"test\": \"ls\"}}")
         allow(Utils).to receive(:popen_read).with(npm_pack_cmd).and_return(`echo pack.tgz`)
-        subject.pack_for_installation
+        described_class.pack_for_installation
         expect(path.read).not_to include("prepare")
         expect(path.read).not_to include("prepack")
         expect(path.read).to include("test")
@@ -45,25 +45,25 @@ describe Language::Node do
 
     it "raises error with non zero exitstatus" do
       allow(Utils).to receive(:popen_read).with(npm_pack_cmd).and_return(`false`)
-      expect { subject.std_npm_install_args(npm_install_arg) }.to \
+      expect { described_class.std_npm_install_args(npm_install_arg) }.to \
         raise_error("npm failed to pack #{Dir.pwd}")
     end
 
     it "raises error with empty npm pack output" do
       allow(Utils).to receive(:popen_read).with(npm_pack_cmd).and_return(`true`)
-      expect { subject.std_npm_install_args(npm_install_arg) }.to \
+      expect { described_class.std_npm_install_args(npm_install_arg) }.to \
         raise_error("npm failed to pack #{Dir.pwd}")
     end
 
     it "does not raise error with a zero exitstatus" do
       allow(Utils).to receive(:popen_read).with(npm_pack_cmd).and_return(`echo pack.tgz`)
-      resp = subject.std_npm_install_args(npm_install_arg)
+      resp = described_class.std_npm_install_args(npm_install_arg)
       expect(resp).to include("--prefix=#{npm_install_arg}", "#{Dir.pwd}/pack.tgz")
     end
   end
 
   specify "#local_npm_install_args" do
-    resp = subject.local_npm_install_args
+    resp = described_class.local_npm_install_args
     expect(resp).to include("-ddd", "--build-from-source", "--cache=#{HOMEBREW_CACHE}/npm_cache")
   end
 end
diff --git a/Library/Homebrew/test/language/python_spec.rb b/Library/Homebrew/test/language/python_spec.rb
index c3eb423ee2..8d5581d63a 100644
--- a/Library/Homebrew/test/language/python_spec.rb
+++ b/Library/Homebrew/test/language/python_spec.rb
@@ -8,28 +8,28 @@ require "utils/shebang"
 describe Language::Python, :needs_python do
   describe "#major_minor_version" do
     it "returns a Version for Python 2" do
-      expect(subject).to receive(:major_minor_version).and_return(Version)
-      subject.major_minor_version("python")
+      expect(described_class).to receive(:major_minor_version).and_return(Version)
+      described_class.major_minor_version("python")
     end
   end
 
   describe "#site_packages" do
     it "gives a different location between PyPy and Python 2" do
-      expect(subject.site_packages("python")).not_to eql(subject.site_packages("pypy"))
+      expect(described_class.site_packages("python")).not_to eql(described_class.site_packages("pypy"))
     end
   end
 
   describe "#homebrew_site_packages" do
     it "returns the Homebrew site packages location" do
-      expect(subject).to receive(:site_packages).and_return(Pathname)
-      subject.site_packages("python")
+      expect(described_class).to receive(:site_packages).and_return(Pathname)
+      described_class.site_packages("python")
     end
   end
 
   describe "#user_site_packages" do
     it "can determine user site packages location" do
-      expect(subject).to receive(:user_site_packages).and_return(Pathname)
-      subject.user_site_packages("python")
+      expect(described_class).to receive(:user_site_packages).and_return(Pathname)
+      described_class.user_site_packages("python")
     end
   end
 end
@@ -77,7 +77,7 @@ describe Language::Python::Shebang do
 end
 
 describe Language::Python::Virtualenv::Virtualenv do
-  subject { described_class.new(formula, dir, "python") }
+  subject(:virtualenv) { described_class.new(formula, dir, "python") }
 
   let(:dir) { mktmpdir }
 
@@ -88,7 +88,7 @@ describe Language::Python::Virtualenv::Virtualenv do
   describe "#create" do
     it "creates a venv" do
       expect(formula).to receive(:system).with("python", "-m", "venv", dir)
-      subject.create
+      virtualenv.create
     end
   end
 
@@ -98,7 +98,7 @@ describe Language::Python::Virtualenv::Virtualenv do
         .with(dir/"bin/pip", "install", "-v", "--no-deps",
               "--no-binary", ":all:", "--no-user", "--ignore-installed", "foo")
         .and_return(true)
-      subject.pip_install "foo"
+      virtualenv.pip_install "foo"
     end
 
     it "accepts a multi-line strings" do
@@ -107,7 +107,7 @@ describe Language::Python::Virtualenv::Virtualenv do
               "--no-binary", ":all:", "--no-user", "--ignore-installed", "foo", "bar")
         .and_return(true)
 
-      subject.pip_install <<~EOS
+      virtualenv.pip_install <<~EOS
         foo
         bar
       EOS
@@ -124,7 +124,7 @@ describe Language::Python::Virtualenv::Virtualenv do
               "--no-binary", ":all:", "--no-user", "--ignore-installed", "bar")
         .and_return(true)
 
-      subject.pip_install ["foo", "bar"]
+      virtualenv.pip_install ["foo", "bar"]
     end
 
     it "accepts a Resource" do
@@ -136,7 +136,7 @@ describe Language::Python::Virtualenv::Virtualenv do
               "--no-binary", ":all:", "--no-user", "--ignore-installed", Pathname.pwd)
         .and_return(true)
 
-      subject.pip_install res
+      virtualenv.pip_install res
     end
   end
 
@@ -155,10 +155,10 @@ describe Language::Python::Virtualenv::Virtualenv do
       FileUtils.touch src_bin/"kilroy"
       bin_after = Dir.glob(src_bin/"*")
 
-      expect(subject).to receive(:pip_install).with("foo")
+      expect(virtualenv).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"
+      virtualenv.pip_install_and_link "foo"
 
       expect(src_bin/"kilroy").to exist
       expect(dest_bin/"kilroy").to exist
diff --git a/Library/Homebrew/test/linkage_cache_store_spec.rb b/Library/Homebrew/test/linkage_cache_store_spec.rb
index 9e9c53385b..2d821ce953 100644
--- a/Library/Homebrew/test/linkage_cache_store_spec.rb
+++ b/Library/Homebrew/test/linkage_cache_store_spec.rb
@@ -4,7 +4,7 @@
 require "linkage_cache_store"
 
 describe LinkageCacheStore do
-  subject { described_class.new(keg_name, database) }
+  subject(:linkage_cache) { described_class.new(keg_name, database) }
 
   let(:keg_name) { "keg_name" }
   let(:database) { double("database") }
@@ -13,14 +13,14 @@ describe LinkageCacheStore do
     context "`keg_name` exists in cache" do
       it "returns `true`" do
         expect(database).to receive(:get).with(keg_name).and_return("")
-        expect(subject.keg_exists?).to be(true)
+        expect(linkage_cache.keg_exists?).to be(true)
       end
     end
 
     context "`keg_name` does not exist in cache" do
       it "returns `false`" do
         expect(database).to receive(:get).with(keg_name).and_return(nil)
-        expect(subject.keg_exists?).to be(false)
+        expect(linkage_cache.keg_exists?).to be(false)
       end
     end
   end
@@ -29,13 +29,13 @@ describe LinkageCacheStore do
     context "a `value` is a `Hash`" do
       it "sets the cache for the `keg_name`" do
         expect(database).to receive(:set).with(keg_name, anything)
-        subject.update!(keg_files_dylibs: { key: ["value"] })
+        linkage_cache.update!(keg_files_dylibs: { key: ["value"] })
       end
     end
 
     context "a `value` is not a `Hash`" do
       it "raises a `TypeError` if a `value` is not a `Hash`" do
-        expect { subject.update!(a_value: ["value"]) }.to raise_error(TypeError)
+        expect { linkage_cache.update!(a_value: ["value"]) }.to raise_error(TypeError)
       end
     end
   end
@@ -43,7 +43,7 @@ describe LinkageCacheStore do
   describe "#delete!" do
     it "calls `delete` on the `database` with `keg_name` as parameter" do
       expect(database).to receive(:delete).with(keg_name)
-      subject.delete!
+      linkage_cache.delete!
     end
   end
 
@@ -51,13 +51,13 @@ describe LinkageCacheStore do
     context "`HASH_LINKAGE_TYPES.include?(type)`" do
       it "returns a `Hash` of values" do
         expect(database).to receive(:get).with(keg_name).and_return(nil)
-        expect(subject.fetch(:keg_files_dylibs)).to be_an_instance_of(Hash)
+        expect(linkage_cache.fetch(:keg_files_dylibs)).to be_an_instance_of(Hash)
       end
     end
 
     context "`type` not in `HASH_LINKAGE_TYPES`" do
       it "raises a `TypeError` if the `type` is not supported" do
-        expect { subject.fetch(:bad_type) }.to raise_error(TypeError)
+        expect { linkage_cache.fetch(:bad_type) }.to raise_error(TypeError)
       end
     end
   end
diff --git a/Library/Homebrew/test/locale_spec.rb b/Library/Homebrew/test/locale_spec.rb
index 05a433122c..f36b9a1ba7 100644
--- a/Library/Homebrew/test/locale_spec.rb
+++ b/Library/Homebrew/test/locale_spec.rb
@@ -58,11 +58,11 @@ describe Locale do
   end
 
   describe "#eql?" do
-    subject { described_class.new("zh", "CN", "Hans") }
+    subject(:locale) { described_class.new("zh", "CN", "Hans") }
 
     context "all parts match" do
       it { is_expected.to eql("zh-CN-Hans") }
-      it { is_expected.to eql(subject) }
+      it { is_expected.to eql(locale) }
     end
 
     context "only some parts match" do
@@ -74,8 +74,8 @@ describe Locale do
     end
 
     it "does not raise if 'other' cannot be parsed" do
-      expect { subject.eql?("zh_CN_Hans") }.not_to raise_error
-      expect(subject.eql?("zh_CN_Hans")).to be false
+      expect { locale.eql?("zh_CN_Hans") }.not_to raise_error
+      expect(locale.eql?("zh_CN_Hans")).to be false
     end
   end
 
diff --git a/Library/Homebrew/test/lock_file_spec.rb b/Library/Homebrew/test/lock_file_spec.rb
index c8aca6bebd..bd420b75b2 100644
--- a/Library/Homebrew/test/lock_file_spec.rb
+++ b/Library/Homebrew/test/lock_file_spec.rb
@@ -4,17 +4,17 @@
 require "lock_file"
 
 describe LockFile do
-  subject { described_class.new("foo") }
+  subject(:lock_file) { described_class.new("foo") }
 
   describe "#lock" do
     it "does not raise an error when already locked" do
-      subject.lock
+      lock_file.lock
 
-      expect { subject.lock }.not_to raise_error
+      expect { lock_file.lock }.not_to raise_error
     end
 
     it "raises an error if a lock already exists" do
-      subject.lock
+      lock_file.lock
 
       expect {
         described_class.new("foo").lock
@@ -24,12 +24,12 @@ describe LockFile do
 
   describe "#unlock" do
     it "does not raise an error when already unlocked" do
-      expect { subject.unlock }.not_to raise_error
+      expect { lock_file.unlock }.not_to raise_error
     end
 
     it "unlocks when locked" do
-      subject.lock
-      subject.unlock
+      lock_file.lock
+      lock_file.unlock
 
       expect { described_class.new("foo").lock }.not_to raise_error
     end
diff --git a/Library/Homebrew/test/migrator_spec.rb b/Library/Homebrew/test/migrator_spec.rb
index 1c21b93ab7..9188985324 100644
--- a/Library/Homebrew/test/migrator_spec.rb
+++ b/Library/Homebrew/test/migrator_spec.rb
@@ -7,7 +7,7 @@ require "tab"
 require "keg"
 
 describe Migrator do
-  subject { described_class.new(new_formula) }
+  subject(:migrator) { described_class.new(new_formula) }
 
   let(:new_formula) { Testball.new("newname") }
   let(:old_formula) { Testball.new("oldname") }
@@ -41,7 +41,7 @@ describe Migrator do
 
     old_pin.make_relative_symlink old_keg_record
 
-    subject # needs to be evaluated eagerly
+    migrator # needs to be evaluated eagerly
 
     (HOMEBREW_PREFIX/"bin").mkpath
   end
@@ -84,7 +84,7 @@ describe Migrator do
 
   specify "#move_to_new_directory" do
     keg.unlink
-    subject.move_to_new_directory
+    migrator.move_to_new_directory
 
     expect(new_keg_record).to be_a_directory
     expect(new_keg_record/"bin").to be_a_directory
@@ -97,7 +97,7 @@ describe Migrator do
     old_keg_record.parent.rmtree
     (new_keg_record/"bin").mkpath
 
-    subject.backup_oldname_cellar
+    migrator.backup_oldname_cellar
 
     expect(old_keg_record/"bin").to be_a_directory
     expect(old_keg_record/"bin").to be_a_directory
@@ -107,18 +107,18 @@ describe Migrator do
     (new_keg_record/"bin").mkpath
     expected_relative = new_keg_record.relative_path_from HOMEBREW_PINNED_KEGS
 
-    subject.repin
+    migrator.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
+    expect(migrator.new_pin_record).to be_a_symlink
+    expect(migrator.new_pin_record.readlink).to eq(expected_relative)
+    expect(migrator.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)
 
-    subject.unlink_oldname
+    migrator.unlink_oldname
 
     expect(HOMEBREW_LINKED_KEGS).not_to exist
     expect(HOMEBREW_LIBRARY/"bin").not_to exist
@@ -133,7 +133,7 @@ describe Migrator do
       FileUtils.touch new_keg_record/"bin"/file
     end
 
-    subject.link_newname
+    migrator.link_newname
 
     expect(HOMEBREW_LINKED_KEGS.children.count).to eq(1)
     expect((HOMEBREW_PREFIX/"opt").children.count).to eq(1)
@@ -141,7 +141,7 @@ describe Migrator do
 
   specify "#link_oldname_opt" do
     new_keg_record.mkpath
-    subject.link_oldname_opt
+    migrator.link_oldname_opt
     expect((HOMEBREW_PREFIX/"opt/oldname").realpath).to eq(new_keg_record.realpath)
   end
 
@@ -149,7 +149,7 @@ describe Migrator do
     (new_keg_record/"bin").mkpath
     keg.unlink
     keg.uninstall
-    subject.link_oldname_cellar
+    migrator.link_oldname_cellar
     expect((HOMEBREW_CELLAR/"oldname").realpath).to eq(new_keg_record.parent.realpath)
   end
 
@@ -159,7 +159,7 @@ describe Migrator do
     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
+    migrator.update_tabs
     expect(Tab.for_keg(new_keg_record).source["path"]).to eq(new_formula.path.to_s)
   end
 
@@ -169,7 +169,7 @@ describe Migrator do
     tab.source["path"] = old_formula.path.to_s
     tab.write
 
-    subject.migrate
+    migrator.migrate
 
     expect(new_keg_record).to exist
     expect(old_keg_record.parent).to be_a_symlink
@@ -187,7 +187,7 @@ describe Migrator do
     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
+    migrator.unlink_oldname_opt
     expect(old_opt_record).not_to be_a_symlink
   end
 
@@ -196,7 +196,7 @@ describe Migrator do
     keg.unlink
     keg.uninstall
     old_keg_record.parent.make_relative_symlink(new_keg_record.parent)
-    subject.unlink_oldname_cellar
+    migrator.unlink_oldname_cellar
     expect(old_keg_record.parent).not_to be_a_symlink
   end
 
@@ -204,7 +204,7 @@ describe Migrator do
     (new_keg_record/"bin").mkpath
     keg.unlink
     keg.uninstall
-    subject.backup_oldname_cellar
+    migrator.backup_oldname_cellar
     expect(old_keg_record.subdirs).not_to be_empty
   end
 
@@ -222,7 +222,7 @@ describe Migrator do
   describe "#backup_oldname" do
     context "when cellar exists" do
       it "backs up the old name" do
-        subject.backup_oldname
+        migrator.backup_oldname
         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
@@ -237,7 +237,7 @@ describe Migrator do
         (new_keg_record/"bin").mkpath
         keg.unlink
         keg.uninstall
-        subject.backup_oldname
+        migrator.backup_oldname
         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
@@ -253,7 +253,7 @@ describe Migrator do
         keg.unlink
         keg.uninstall
         old_keg_record.parent.make_relative_symlink(new_keg_record.parent)
-        subject.backup_oldname
+        migrator.backup_oldname
         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
diff --git a/Library/Homebrew/test/options_spec.rb b/Library/Homebrew/test/options_spec.rb
index fa180493f6..52ed91a17e 100644
--- a/Library/Homebrew/test/options_spec.rb
+++ b/Library/Homebrew/test/options_spec.rb
@@ -4,136 +4,138 @@
 require "options"
 
 describe Option do
-  subject { described_class.new("foo") }
+  subject(:option) { described_class.new("foo") }
 
   specify "#to_s" do
-    expect(subject.to_s).to eq("--foo")
+    expect(option.to_s).to eq("--foo")
   end
 
   specify "equality" do
     foo = described_class.new("foo")
     bar = described_class.new("bar")
-    expect(subject).to eq(foo)
-    expect(subject).not_to eq(bar)
-    expect(subject).to eql(foo)
-    expect(subject).not_to eql(bar)
+    expect(option).to eq(foo)
+    expect(option).not_to eq(bar)
+    expect(option).to eql(foo)
+    expect(option).not_to eql(bar)
   end
 
   specify "#description" do
-    expect(subject.description).to be_empty
+    expect(option.description).to be_empty
     expect(described_class.new("foo", "foo").description).to eq("foo")
   end
 
   specify "#inspect" do
-    expect(subject.inspect).to eq("#<Option: \"--foo\">")
+    expect(option.inspect).to eq("#<Option: \"--foo\">")
   end
 end
 
 describe DeprecatedOption do
-  subject { described_class.new("foo", "bar") }
+  subject(:option) { described_class.new("foo", "bar") }
 
   specify "#old" do
-    expect(subject.old).to eq("foo")
+    expect(option.old).to eq("foo")
   end
 
   specify "#old_flag" do
-    expect(subject.old_flag).to eq("--foo")
+    expect(option.old_flag).to eq("--foo")
   end
 
   specify "#current" do
-    expect(subject.current).to eq("bar")
+    expect(option.current).to eq("bar")
   end
 
   specify "#current_flag" do
-    expect(subject.current_flag).to eq("--bar")
+    expect(option.current_flag).to eq("--bar")
   end
 
   specify "equality" do
     foobar = described_class.new("foo", "bar")
     boofar = described_class.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)
+    expect(foobar).to eq(option)
+    expect(option).to eq(foobar)
+    expect(boofar).not_to eq(option)
+    expect(option).not_to eq(boofar)
   end
 end
 
 describe Options do
+  subject(:options) { described_class.new }
+
   it "removes duplicate options" do
-    subject << Option.new("foo")
-    subject << Option.new("foo")
-    expect(subject).to include("--foo")
-    expect(subject.count).to eq(1)
+    options << Option.new("foo")
+    options << Option.new("foo")
+    expect(options).to include("--foo")
+    expect(options.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)
+    options << a << b
+    expect(options.count).to eq(1)
+    expect(options.first).to be(a)
+    expect(options.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"))
+    options << Option.new("foo")
+    expect(options).to include("--foo")
+    expect(options).to include("foo")
+    expect(options).to include(Option.new("foo"))
   end
 
   describe "#+" do
     it "returns options" do
-      expect(subject + described_class.new).to be_an_instance_of(described_class)
+      expect(options + described_class.new).to be_an_instance_of(described_class)
     end
   end
 
   describe "#-" do
     it "returns options" do
-      expect(subject - described_class.new).to be_an_instance_of(described_class)
+      expect(options - described_class.new).to be_an_instance_of(described_class)
     end
   end
 
   specify "#&" do
     foo, bar, baz = %w[foo bar baz].map { |o| Option.new(o) }
-    options = described_class.new << foo << bar
-    subject << foo << baz
-    expect((subject & options).to_a).to eq([foo])
+    other_options = described_class.new << foo << bar
+    options << foo << baz
+    expect((options & other_options).to_a).to eq([foo])
   end
 
   specify "#|" do
     foo, bar, baz = %w[foo bar baz].map { |o| Option.new(o) }
-    options = described_class.new << foo << bar
-    subject << foo << baz
-    expect((subject | options).sort).to eq([foo, bar, baz].sort)
+    other_options = described_class.new << foo << bar
+    options << foo << baz
+    expect((options | other_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])
+    options << Option.new("aa") << Option.new("bb") << Option.new("cc")
+    expect((options * "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
+      expect(options << Option.new("foo")).to be options
     end
   end
 
   specify "#as_flags" do
-    subject << Option.new("foo")
-    expect(subject.as_flags).to eq(%w[--foo])
+    options << Option.new("foo")
+    expect(options.as_flags).to eq(%w[--foo])
   end
 
   specify "#to_a" do
     option = Option.new("foo")
-    subject << option
-    expect(subject.to_a).to eq([option])
+    options << option
+    expect(options.to_a).to eq([option])
   end
 
   specify "#to_ary" do
     option = Option.new("foo")
-    subject << option
-    expect(subject.to_ary).to eq([option])
+    options << option
+    expect(options.to_ary).to eq([option])
   end
 
   specify "::create_with_array" do
@@ -144,8 +146,8 @@ describe Options do
   end
 
   specify "#inspect" do
-    expect(subject.inspect).to eq("#<Options: []>")
-    subject << Option.new("foo")
-    expect(subject.inspect).to eq("#<Options: [#<Option: \"--foo\">]>")
+    expect(options.inspect).to eq("#<Options: []>")
+    options << Option.new("foo")
+    expect(options.inspect).to eq("#<Options: [#<Option: \"--foo\">]>")
   end
 end
diff --git a/Library/Homebrew/test/os/linux/dependency_collector_spec.rb b/Library/Homebrew/test/os/linux/dependency_collector_spec.rb
index 3baab3f2d4..02a6362dc7 100644
--- a/Library/Homebrew/test/os/linux/dependency_collector_spec.rb
+++ b/Library/Homebrew/test/os/linux/dependency_collector_spec.rb
@@ -6,6 +6,8 @@ require "dependency_collector"
 describe DependencyCollector do
   alias_matcher :be_a_build_requirement, :be_build
 
+  subject(:collector) { described_class.new }
+
   describe "#add" do
     resource = Resource.new
 
@@ -13,19 +15,19 @@ describe DependencyCollector do
       it "creates a resource dependency from a '.xz' URL" do
         resource.url("https://brew.sh/foo.xz")
         allow_any_instance_of(Object).to receive(:which).with("xz")
-        expect(subject.add(resource)).to eq(Dependency.new("xz", [:build, :test]))
+        expect(collector.add(resource)).to eq(Dependency.new("xz", [:build, :test]))
       end
 
       it "creates a resource dependency from a '.zip' URL" do
         resource.url("https://brew.sh/foo.zip")
         allow_any_instance_of(Object).to receive(:which).with("unzip")
-        expect(subject.add(resource)).to eq(Dependency.new("unzip", [:build, :test]))
+        expect(collector.add(resource)).to eq(Dependency.new("unzip", [:build, :test]))
       end
 
       it "creates a resource dependency from a '.bz2' URL" do
         resource.url("https://brew.sh/foo.tar.bz2")
         allow_any_instance_of(Object).to receive(:which).with("bzip2")
-        expect(subject.add(resource)).to eq(Dependency.new("bzip2", [:build, :test]))
+        expect(collector.add(resource)).to eq(Dependency.new("bzip2", [:build, :test]))
       end
     end
 
@@ -33,19 +35,19 @@ describe DependencyCollector do
       it "does not create a resource dependency from a '.xz' URL" do
         resource.url("https://brew.sh/foo.xz")
         allow_any_instance_of(Object).to receive(:which).with("xz").and_return(Pathname.new("foo"))
-        expect(subject.add(resource)).to be nil
+        expect(collector.add(resource)).to be nil
       end
 
       it "does not create a resource dependency from a '.zip' URL" do
         resource.url("https://brew.sh/foo.zip")
         allow_any_instance_of(Object).to receive(:which).with("unzip").and_return(Pathname.new("foo"))
-        expect(subject.add(resource)).to be nil
+        expect(collector.add(resource)).to be nil
       end
 
       it "does not create a resource dependency from a '.bz2' URL" do
         resource.url("https://brew.sh/foo.tar.bz2")
         allow_any_instance_of(Object).to receive(:which).with("bzip2").and_return(Pathname.new("foo"))
-        expect(subject.add(resource)).to be nil
+        expect(collector.add(resource)).to be nil
       end
     end
   end
diff --git a/Library/Homebrew/test/os/linux/diagnostic_spec.rb b/Library/Homebrew/test/os/linux/diagnostic_spec.rb
index 8c32c83198..b97268677a 100644
--- a/Library/Homebrew/test/os/linux/diagnostic_spec.rb
+++ b/Library/Homebrew/test/os/linux/diagnostic_spec.rb
@@ -4,24 +4,26 @@
 require "diagnostic"
 
 describe Homebrew::Diagnostic::Checks do
+  subject(:checks) { described_class.new }
+
   specify "#check_supported_architecture" do
     allow(Hardware::CPU).to receive(:type).and_return(:arm64)
 
-    expect(subject.check_supported_architecture)
+    expect(checks.check_supported_architecture)
       .to match(/Your CPU architecture .+ is not supported/)
   end
 
   specify "#check_glibc_minimum_version" do
     allow(OS::Linux::Glibc).to receive(:below_minimum_version?).and_return(true)
 
-    expect(subject.check_glibc_minimum_version)
+    expect(checks.check_glibc_minimum_version)
       .to match(/Your system glibc .+ is too old/)
   end
 
   specify "#check_kernel_minimum_version" do
     allow(OS::Linux::Kernel).to receive(:below_minimum_version?).and_return(true)
 
-    expect(subject.check_kernel_minimum_version)
+    expect(checks.check_kernel_minimum_version)
       .to match(/Your Linux kernel .+ is too old/)
   end
 end
diff --git a/Library/Homebrew/test/os/mac/dependency_collector_spec.rb b/Library/Homebrew/test/os/mac/dependency_collector_spec.rb
index eb29d478d5..cad682f1a1 100644
--- a/Library/Homebrew/test/os/mac/dependency_collector_spec.rb
+++ b/Library/Homebrew/test/os/mac/dependency_collector_spec.rb
@@ -6,37 +6,39 @@ require "dependency_collector"
 describe DependencyCollector do
   alias_matcher :need_tar_xz_dependency, :be_tar_needs_xz_dependency
 
+  subject(:collector) { described_class.new }
+
   specify "Resource dependency from a '.xz' URL" do
     resource = Resource.new
     resource.url("https://brew.sh/foo.tar.xz")
-    expect(subject.add(resource)).to be nil
+    expect(collector.add(resource)).to be nil
   end
 
   specify "Resource dependency from a '.zip' URL" do
     resource = Resource.new
     resource.url("https://brew.sh/foo.zip")
-    expect(subject.add(resource)).to be nil
+    expect(collector.add(resource)).to be nil
   end
 
   specify "Resource dependency from a '.bz2' URL" do
     resource = Resource.new
     resource.url("https://brew.sh/foo.tar.bz2")
-    expect(subject.add(resource)).to be nil
+    expect(collector.add(resource)).to be nil
   end
 
   specify "Resource dependency from a '.git' URL" do
     resource = Resource.new
     resource.url("git://brew.sh/foo/bar.git")
-    expect(subject.add(resource)).to be nil
+    expect(collector.add(resource)).to be nil
   end
 
   specify "Resource dependency from a Subversion URL" do
     resource = Resource.new
     resource.url("svn://brew.sh/foo/bar")
     if MacOS.version < :catalina
-      expect(subject.add(resource)).to be nil
+      expect(collector.add(resource)).to be nil
     else
-      expect(subject.add(resource)).not_to be nil
+      expect(collector.add(resource)).not_to be nil
     end
   end
 end
diff --git a/Library/Homebrew/test/os/mac/diagnostic_spec.rb b/Library/Homebrew/test/os/mac/diagnostic_spec.rb
index ad6f14632e..f58aef8cff 100644
--- a/Library/Homebrew/test/os/mac/diagnostic_spec.rb
+++ b/Library/Homebrew/test/os/mac/diagnostic_spec.rb
@@ -4,6 +4,8 @@
 require "diagnostic"
 
 describe Homebrew::Diagnostic::Checks do
+  subject(:checks) { described_class.new }
+
   specify "#check_for_unsupported_macos" do
     ENV.delete("HOMEBREW_DEVELOPER")
 
@@ -12,7 +14,7 @@ describe Homebrew::Diagnostic::Checks do
     allow(OS::Mac).to receive(:full_version).and_return(macos_version)
     allow(OS::Mac).to receive(:prerelease?).and_return(true)
 
-    expect(subject.check_for_unsupported_macos)
+    expect(checks.check_for_unsupported_macos)
       .to match("We do not provide support for this pre-release version.")
   end
 
@@ -24,7 +26,7 @@ describe Homebrew::Diagnostic::Checks do
     allow(OS::Mac::Xcode).to receive(:version).and_return("8.0")
     allow(OS::Mac::Xcode).to receive(:without_clt?).and_return(true)
 
-    expect(subject.check_if_xcode_needs_clt_installed)
+    expect(checks.check_if_xcode_needs_clt_installed)
       .to match("Xcode alone is not sufficient on El Capitan")
   end
 
@@ -34,7 +36,7 @@ describe Homebrew::Diagnostic::Checks do
     allow(OS::Mac).to receive(:full_version).and_return(macos_version)
     stub_const("RUBY_VERSION", "1.8.6")
 
-    expect(subject.check_ruby_version)
+    expect(checks.check_ruby_version)
       .to match "Ruby version 1.8.6 is unsupported on 10.12"
   end
 end
diff --git a/Library/Homebrew/test/os/mac/keg_spec.rb b/Library/Homebrew/test/os/mac/keg_spec.rb
index 6ce7bc0758..267d510135 100644
--- a/Library/Homebrew/test/os/mac/keg_spec.rb
+++ b/Library/Homebrew/test/os/mac/keg_spec.rb
@@ -6,21 +6,21 @@ require "keg"
 describe Keg do
   include FileUtils
 
-  subject { described_class.new(keg_path) }
+  subject(:keg) { described_class.new(keg_path) }
 
   describe "#mach_o_files" do
     let(:keg_path) { HOMEBREW_CELLAR/"a/1.0" }
 
     before { (keg_path/"lib").mkpath }
 
-    after { subject.unlink }
+    after { keg.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)
+      keg.link
+      expect(keg.mach_o_files.count).to eq(1)
     end
 
     it "isn't confused by symlinks" do
@@ -28,8 +28,8 @@ describe Keg do
       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)
+      keg.link
+      expect(keg.mach_o_files.count).to eq(1)
     end
   end
 end
diff --git a/Library/Homebrew/test/os/mac_spec.rb b/Library/Homebrew/test/os/mac_spec.rb
index d7fff66b2a..1379cc3993 100644
--- a/Library/Homebrew/test/os/mac_spec.rb
+++ b/Library/Homebrew/test/os/mac_spec.rb
@@ -7,13 +7,13 @@ require "os/mac"
 describe OS::Mac do
   describe "::languages" do
     it "returns a list of all languages" do
-      expect(subject.languages).not_to be_empty
+      expect(described_class.languages).not_to be_empty
     end
   end
 
   describe "::language" do
     it "returns the first item from #languages" do
-      expect(subject.language).to eq(subject.languages.first)
+      expect(described_class.language).to eq(described_class.languages.first)
     end
   end
 
diff --git a/Library/Homebrew/test/patch_spec.rb b/Library/Homebrew/test/patch_spec.rb
index 1708cd39ca..cd03b0a100 100644
--- a/Library/Homebrew/test/patch_spec.rb
+++ b/Library/Homebrew/test/patch_spec.rb
@@ -53,26 +53,26 @@ describe Patch do
   end
 
   describe "#patch_files" do
-    subject { described_class.create(:p2, nil) }
+    subject(:patch) { described_class.create(:p2, nil) }
 
     context "empty patch" do
       its(:resource) { is_expected.to be_kind_of Resource::PatchResource }
-      its(:patch_files) { is_expected.to eq(subject.resource.patch_files) }
+      its(:patch_files) { is_expected.to eq(patch.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"])
+      patch.resource.apply("patch1.diff")
+      expect(patch.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"])
+      patch.resource.apply("patch2.diff", "patch3.diff")
+      expect(patch.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)
+      patch.resource.apply(["patch4.diff", "patch5.diff"])
+      expect(patch.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)
+      patch.resource.apply("patch4.diff", ["patch5.diff", "patch6.diff"], "patch7.diff")
+      expect(patch.patch_files.count).to eq(7)
     end
   end
 end
@@ -86,7 +86,7 @@ describe EmbeddedPatch do
 end
 
 describe ExternalPatch do
-  subject { described_class.new(:p1) { url "file:///my.patch" } }
+  subject(:patch) { described_class.new(:p1) { url "file:///my.patch" } }
 
   describe "#url" do
     its(:url) { is_expected.to eq("file:///my.patch") }
@@ -98,7 +98,7 @@ describe ExternalPatch do
 
   describe "#cached_download" do
     before do
-      allow(subject.resource).to receive(:cached_download).and_return("/tmp/foo.tar.gz")
+      allow(patch.resource).to receive(:cached_download).and_return("/tmp/foo.tar.gz")
     end
 
     its(:cached_download) { is_expected.to eq("/tmp/foo.tar.gz") }
diff --git a/Library/Homebrew/test/requirement_spec.rb b/Library/Homebrew/test/requirement_spec.rb
index 5f2b007c81..7e082d2b0f 100644
--- a/Library/Homebrew/test/requirement_spec.rb
+++ b/Library/Homebrew/test/requirement_spec.rb
@@ -7,7 +7,7 @@ require "requirement"
 describe Requirement do
   alias_matcher :be_a_build_requirement, :be_a_build
 
-  subject { klass.new }
+  subject(:requirement) { klass.new }
 
   let(:klass) { Class.new(described_class) }
 
@@ -111,7 +111,7 @@ describe Requirement do
 
       it "sets up build environment" do
         expect(ENV).to receive(:with_build_environment).and_call_original
-        subject.satisfied?
+        requirement.satisfied?
       end
     end
 
@@ -126,7 +126,7 @@ describe Requirement do
 
       it "skips setting up build environment" do
         expect(ENV).not_to receive(:with_build_environment)
-        subject.satisfied?
+        requirement.satisfied?
       end
     end
 
@@ -141,8 +141,8 @@ describe Requirement do
 
       it "infers path from #satisfy result" do
         expect(ENV).to receive(:prepend_path).with("PATH", Pathname.new("/foo/bar"))
-        subject.satisfied?
-        subject.modify_build_environment
+        requirement.satisfied?
+        requirement.modify_build_environment
       end
     end
   end
@@ -180,53 +180,53 @@ describe Requirement do
       let(:klass) { Class.new(described_class) }
 
       it "returns nil" do
-        expect(subject.modify_build_environment).to be nil
+        expect(requirement.modify_build_environment).to be nil
       end
     end
   end
 
   describe "#eql? and #==" do
-    subject { described_class.new }
+    subject(:requirement) { 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)
+      expect(requirement).to eql(other)
+      expect(requirement).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)
+      expect(requirement).not_to eql(other)
+      expect(requirement).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)
+      expect(requirement).not_to eql(other)
+      expect(requirement).not_to eq(other)
     end
   end
 
   describe "#hash" do
-    subject { described_class.new }
+    subject(:requirement) { described_class.new }
 
     it "is equal if names and tags are equal" do
       other = described_class.new
-      expect(subject.hash).to eq(other.hash)
+      expect(requirement.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)
+      expect(requirement.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)
+      expect(requirement.hash).not_to eq(other.hash)
     end
   end
 end
diff --git a/Library/Homebrew/test/requirements_spec.rb b/Library/Homebrew/test/requirements_spec.rb
index 9d65e513c9..a915c926cd 100644
--- a/Library/Homebrew/test/requirements_spec.rb
+++ b/Library/Homebrew/test/requirements_spec.rb
@@ -4,14 +4,16 @@
 require "requirements"
 
 describe Requirements do
+  subject(:requirements) { described_class.new }
+
   describe "#<<" do
     it "returns itself" do
-      expect(subject << Object.new).to be(subject)
+      expect(requirements << Object.new).to be(requirements)
     end
 
     it "merges duplicate requirements" do
-      subject << Requirement.new << Requirement.new
-      expect(subject.count).to eq(1)
+      requirements << Requirement.new << Requirement.new
+      expect(requirements.count).to eq(1)
     end
   end
 end
diff --git a/Library/Homebrew/test/resource_spec.rb b/Library/Homebrew/test/resource_spec.rb
index 9c3f294ce7..29513698e0 100644
--- a/Library/Homebrew/test/resource_spec.rb
+++ b/Library/Homebrew/test/resource_spec.rb
@@ -4,111 +4,111 @@
 require "resource"
 
 describe Resource do
-  subject { described_class.new("test") }
+  subject(:resource) { described_class.new("test") }
 
   describe "#url" do
     it "sets the URL" do
-      subject.url("foo")
-      expect(subject.url).to eq("foo")
+      resource.url("foo")
+      expect(resource.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")
+      resource.url("foo", branch: "master")
+      expect(resource.url).to eq("foo")
+      expect(resource.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)
+      resource.url("foo", using: strategy)
+      expect(resource.url).to eq("foo")
+      expect(resource.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)
+      resource.url("foo", using: strategy, branch: "master")
+      expect(resource.url).to eq("foo")
+      expect(resource.specs).to eq(branch: "master")
+      expect(resource.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)
+      resource.url("foo", using: :git)
+      expect(resource.url).to eq("foo")
+      expect(resource.download_strategy).to eq(GitDownloadStrategy)
     end
 
     it "raises an error if the download strategy class is unknown" do
-      expect { subject.url("foo", using: Class.new) }.to raise_error(TypeError)
+      expect { resource.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)
+      resource.url("foo", specs)
+      expect(resource.specs).to eq(branch: "master")
+      expect(resource.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
+      resource.version("1.0")
+      expect(resource.version).to eq(Version.parse("1.0"))
+      expect(resource.version).not_to be_detected_from_url
     end
 
     it "can detect the version from a URL" do
-      subject.url("https://brew.sh/foo-1.0.tar.gz")
-      expect(subject.version).to eq(Version.parse("1.0"))
-      expect(subject.version).to be_detected_from_url
+      resource.url("https://brew.sh/foo-1.0.tar.gz")
+      expect(resource.version).to eq(Version.parse("1.0"))
+      expect(resource.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)
+      resource.version klass.new("1.0")
+      expect(resource.version).to eq(Version.parse("1.0"))
+      expect(resource.version).to be_a(klass)
     end
 
     it "can set the version from a tag" do
-      subject.url("https://brew.sh/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
+      resource.url("https://brew.sh/foo-1.0.tar.gz", tag: "v1.0.2")
+      expect(resource.version).to eq(Version.parse("1.0.2"))
+      expect(resource.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)
+      expect { resource.version(1) }.to raise_error(TypeError)
+      expect { resource.version(2.0) }.to raise_error(TypeError)
+      expect { resource.version(Object.new) }.to raise_error(TypeError)
     end
 
     it "returns nil if unset" do
-      expect(subject.version).to be nil
+      expect(resource.version).to be nil
     end
   end
 
   describe "#mirrors" do
     it "is empty by defaults" do
-      expect(subject.mirrors).to be_empty
+      expect(resource.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])
+      resource.mirror("foo")
+      resource.mirror("bar")
+      expect(resource.mirrors).to eq(%w[foo bar])
     end
   end
 
   describe "#checksum" do
     it "returns nil if unset" do
-      expect(subject.checksum).to be nil
+      expect(resource.checksum).to be nil
     end
 
     it "returns the checksum set with #sha256" do
-      subject.sha256(TEST_SHA256)
-      expect(subject.checksum).to eq(Checksum.new(TEST_SHA256))
+      resource.sha256(TEST_SHA256)
+      expect(resource.checksum).to eq(Checksum.new(TEST_SHA256))
     end
   end
 
@@ -117,23 +117,23 @@ describe Resource 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)
+      resource.url("foo")
+      expect(resource.download_strategy).to eq(strategy)
     end
   end
 
   describe "#owner" do
     it "sets the owner" do
       owner = Object.new
-      subject.owner = owner
-      expect(subject.owner).to eq(owner)
+      resource.owner = owner
+      expect(resource.owner).to eq(owner)
     end
 
     it "sets its owner to be the patches' owner" do
-      subject.patch(:p1) { url "file:///my.patch" }
+      resource.patch(:p1) { url "file:///my.patch" }
       owner = Object.new
-      subject.owner = owner
-      subject.patches.each do |p|
+      resource.owner = owner
+      resource.patches.each do |p|
         expect(p.resource.owner).to eq(owner)
       end
     end
@@ -141,9 +141,9 @@ describe Resource do
 
   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)
+      resource.patch(:p1, :DATA)
+      expect(resource.patches.count).to eq(1)
+      expect(resource.patches.first.strip).to eq(:p1)
     end
   end
 
@@ -154,18 +154,18 @@ describe Resource do
     expect(fn).to receive(:verify_checksum).and_raise(ChecksumMissingError)
     expect(fn).to receive(:sha256)
 
-    subject.verify_download_integrity(fn)
+    resource.verify_download_integrity(fn)
   end
 
   specify "#verify_download_integrity_mismatch" do
     fn = double(file?: true, basename: "foo")
-    checksum = subject.sha256(TEST_SHA256)
+    checksum = resource.sha256(TEST_SHA256)
 
     expect(fn).to receive(:verify_checksum).with(checksum)
       .and_raise(ChecksumMismatchError.new(fn, checksum, Object.new))
 
     expect {
-      subject.verify_download_integrity(fn)
+      resource.verify_download_integrity(fn)
     }.to raise_error(ChecksumMismatchError)
   end
 end
diff --git a/Library/Homebrew/test/sandbox_spec.rb b/Library/Homebrew/test/sandbox_spec.rb
index 10f4abde6c..2d827f9e06 100644
--- a/Library/Homebrew/test/sandbox_spec.rb
+++ b/Library/Homebrew/test/sandbox_spec.rb
@@ -6,6 +6,8 @@ require "sandbox"
 describe Sandbox, :needs_macos do
   define_negated_matcher :not_matching, :matching
 
+  subject(:sandbox) { described_class.new }
+
   let(:dir) { mktmpdir }
   let(:file) { dir/"foo" }
 
@@ -14,8 +16,8 @@ describe Sandbox, :needs_macos do
   end
 
   specify "#allow_write" do
-    subject.allow_write file
-    subject.exec "touch", file
+    sandbox.allow_write file
+    sandbox.exec "touch", file
 
     expect(file).to exist
   end
@@ -23,7 +25,7 @@ describe Sandbox, :needs_macos do
   describe "#exec" do
     it "fails when writing to file not specified with ##allow_write" do
       expect {
-        subject.exec "touch", file
+        sandbox.exec "touch", file
       }.to raise_error(ErrorDuringExecution)
 
       expect(file).not_to exist
@@ -34,7 +36,7 @@ describe Sandbox, :needs_macos do
 
       expect(Utils).to receive(:popen_read).and_return("foo")
 
-      expect { subject.exec "false" }
+      expect { sandbox.exec "false" }
         .to raise_error(ErrorDuringExecution)
         .and output(/foo/).to_stdout
     end
@@ -49,7 +51,7 @@ describe Sandbox, :needs_macos do
       EOS
       expect(Utils).to receive(:popen_read).and_return(with_bogus_error)
 
-      expect { subject.exec "false" }
+      expect { sandbox.exec "false" }
         .to raise_error(ErrorDuringExecution)
         .and output(a_string_matching(/foo/).and(matching(/bar/).and(not_matching(/Python/)))).to_stdout
     end
diff --git a/Library/Homebrew/test/searchable_spec.rb b/Library/Homebrew/test/searchable_spec.rb
index f7e059ffb0..7a1f9cacbb 100644
--- a/Library/Homebrew/test/searchable_spec.rb
+++ b/Library/Homebrew/test/searchable_spec.rb
@@ -4,7 +4,7 @@
 require "searchable"
 
 describe Searchable do
-  subject { collection.extend(described_class) }
+  subject(:searchable_collection) { collection.extend(described_class) }
 
   let(:collection) { ["with-dashes"] }
 
@@ -13,20 +13,20 @@ describe Searchable do
       let(:collection) { [["with-dashes", "withdashes"]] }
 
       it "searches by the selected argument" do
-        expect(subject.search(/withdashes/) { |_, short_name| short_name }).not_to be_empty
-        expect(subject.search(/withdashes/) { |long_name, _| long_name }).to be_empty
+        expect(searchable_collection.search(/withdashes/) { |_, short_name| short_name }).not_to be_empty
+        expect(searchable_collection.search(/withdashes/) { |long_name, _| long_name }).to be_empty
       end
     end
 
     context "when given a regex" do
       it "does not simplify strings" do
-        expect(subject.search(/with-dashes/)).to eq ["with-dashes"]
+        expect(searchable_collection.search(/with-dashes/)).to eq ["with-dashes"]
       end
     end
 
     context "when given a string" do
       it "simplifies both the query and searched strings" do
-        expect(subject.search("with dashes")).to eq ["with-dashes"]
+        expect(searchable_collection.search("with dashes")).to eq ["with-dashes"]
       end
     end
 
@@ -34,14 +34,14 @@ describe Searchable do
       let(:collection) { { "foo" => "bar" } }
 
       it "returns a Hash" do
-        expect(subject.search("foo")).to eq "foo" => "bar"
+        expect(searchable_collection.search("foo")).to eq "foo" => "bar"
       end
 
       context "containing nil" do
         let(:collection) { { "foo" => nil } }
 
         it "does not raise an error" do
-          expect(subject.search("foo")).to eq "foo" => nil
+          expect(searchable_collection.search("foo")).to eq "foo" => nil
         end
       end
     end
diff --git a/Library/Homebrew/test/software_spec_spec.rb b/Library/Homebrew/test/software_spec_spec.rb
index 1cfd058adb..85ff8e1b10 100644
--- a/Library/Homebrew/test/software_spec_spec.rb
+++ b/Library/Homebrew/test/software_spec_spec.rb
@@ -7,182 +7,188 @@ describe SoftwareSpec do
   alias_matcher :have_defined_resource, :be_resource_defined
   alias_matcher :have_defined_option, :be_option_defined
 
+  subject(:spec) { described_class.new }
+
   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")
+      spec.resource("foo") { url "foo-1.0" }
+      expect(spec).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)
+      spec.resource("foo") { url "foo-1.0" }
+      spec.owner = owner
+      spec.resources.each_value do |r|
+        expect(r.owner).to eq(spec)
       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
+      spec.url("foo-42")
+      spec.resource("bar") { url "bar" }
+      spec.owner = owner
 
-      expect(subject.resource("bar").version).to eq("42")
+      expect(spec.resource("bar").version).to eq("42")
     end
 
     it "raises an error when duplicate resources are defined" do
-      subject.resource("foo") { url "foo-1.0" }
+      spec.resource("foo") { url "foo-1.0" }
       expect {
-        subject.resource("foo") { url "foo-1.0" }
+        spec.resource("foo") { url "foo-1.0" }
       }.to raise_error(DuplicateResourceError)
     end
 
     it "raises an error when accessing missing resources" do
-      subject.owner = owner
+      spec.owner = owner
       expect {
-        subject.resource("foo")
+        spec.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)
+      spec.owner = owner
+      expect(spec.owner).to eq(owner)
     end
 
     it "sets the name" do
-      subject.owner = owner
-      expect(subject.name).to eq(owner.name)
+      spec.owner = owner
+      expect(spec.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")
+      spec.option("foo")
+      expect(spec).to have_defined_option("foo")
     end
 
     it "raises an error when it begins with dashes" do
       expect {
-        subject.option("--foo")
+        spec.option("--foo")
       }.to raise_error(ArgumentError)
     end
 
     it "raises an error when name is empty" do
       expect {
-        subject.option("")
+        spec.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")
+      spec.option(:cxx11)
+      expect(spec).to have_defined_option("c++11")
+      expect(spec).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")
+      spec.option("bar", "description")
+      expect(spec.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("")
+      spec.option("foo")
+      expect(spec.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")
+      spec.deprecated_option("foo" => "bar")
+      expect(spec.deprecated_options).not_to be_empty
+      expect(spec.deprecated_options.first.old).to eq("foo")
+      expect(spec.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"))
+      spec.deprecated_option(["foo1", "foo2"] => "bar1", "foo3" => ["bar2", "bar3"])
+      expect(spec.deprecated_options).to include(DeprecatedOption.new("foo1", "bar1"))
+      expect(spec.deprecated_options).to include(DeprecatedOption.new("foo2", "bar1"))
+      expect(spec.deprecated_options).to include(DeprecatedOption.new("foo3", "bar2"))
+      expect(spec.deprecated_options).to include(DeprecatedOption.new("foo3", "bar3"))
     end
 
     it "raises an error when empty" do
       expect {
-        subject.deprecated_option({})
+        spec.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")
+      spec.depends_on("foo")
+      expect(spec.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")
+      spec.depends_on "foo" => :optional
+      expect(spec).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")
+      spec.depends_on "bar" => :recommended
+      expect(spec).to have_defined_option("without-bar")
     end
   end
 
   describe "#uses_from_macos" do
     it "allows specifying dependencies", :needs_linux do
-      subject.uses_from_macos("foo")
+      spec.uses_from_macos("foo")
 
-      expect(subject.deps.first.name).to eq("foo")
+      expect(spec.deps.first.name).to eq("foo")
     end
 
     it "works with tags", :needs_linux do
-      subject.uses_from_macos("foo" => :build)
+      spec.uses_from_macos("foo" => :build)
 
-      expect(subject.deps.first.name).to eq("foo")
-      expect(subject.deps.first.tags).to include(:build)
+      expect(spec.deps.first.name).to eq("foo")
+      expect(spec.deps.first.tags).to include(:build)
     end
 
     it "ignores OS version specifications", :needs_linux do
-      subject.uses_from_macos("foo", since: :mojave)
-      subject.uses_from_macos("bar" => :build, :since => :mojave)
+      spec.uses_from_macos("foo", since: :mojave)
+      spec.uses_from_macos("bar" => :build, :since => :mojave)
 
-      expect(subject.deps.first.name).to eq("foo")
-      expect(subject.deps.last.name).to eq("bar")
-      expect(subject.deps.last.tags).to include(:build)
+      expect(spec.deps.first.name).to eq("foo")
+      expect(spec.deps.last.name).to eq("bar")
+      expect(spec.deps.last.tags).to include(:build)
     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")
+    spec.option("with-foo", "blah")
+    spec.depends_on("foo" => :optional)
+    expect(spec.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)
+      spec.patch(:p1, :DATA)
+      expect(spec.patches.count).to eq(1)
+      expect(spec.patches.first.strip).to eq(:p1)
     end
   end
 end
 
 describe HeadSoftwareSpec do
+  subject(:head_spec) { described_class.new }
+
   specify "#version" do
-    expect(subject.version).to eq(Version.create("HEAD"))
+    expect(head_spec.version).to eq(Version.create("HEAD"))
   end
 
   specify "#verify_download_integrity" do
-    expect(subject.verify_download_integrity(Object.new)).to be nil
+    expect(head_spec.verify_download_integrity(Object.new)).to be nil
   end
 end
 
 describe BottleSpecification do
+  subject(:bottle_spec) { described_class.new }
+
   describe "#sha256" do
     it "works without cellar" do
       checksums = {
@@ -193,8 +199,8 @@ describe BottleSpecification do
       }
 
       checksums.each_pair do |cat, digest|
-        subject.sha256(digest => cat)
-        checksum, = subject.checksum_for(cat)
+        bottle_spec.sha256(digest => cat)
+        checksum, = bottle_spec.checksum_for(cat)
         expect(Checksum.new(digest)).to eq(checksum)
       end
     end
@@ -208,8 +214,8 @@ describe BottleSpecification do
       ]
 
       checksums.each do |checksum|
-        subject.sha256(checksum[:tag] => checksum[:digest], cellar: checksum[:cellar])
-        digest, tag, cellar = subject.checksum_for(checksum[:tag])
+        bottle_spec.sha256(checksum[:tag] => checksum[:digest], cellar: checksum[:cellar])
+        digest, tag, cellar = bottle_spec.checksum_for(checksum[:tag])
         expect(Checksum.new(checksum[:digest])).to eq(digest)
         expect(checksum[:tag]).to eq(tag)
         checksum[:cellar] ||= Homebrew::DEFAULT_CELLAR
@@ -221,8 +227,8 @@ describe BottleSpecification do
   %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)
+      bottle_spec.public_send(method, object)
+      expect(bottle_spec.public_send(method)).to eq(object)
     end
   end
 end
diff --git a/Library/Homebrew/test/system_command_result_spec.rb b/Library/Homebrew/test/system_command_result_spec.rb
index 8d37dbf57e..5ce216387d 100644
--- a/Library/Homebrew/test/system_command_result_spec.rb
+++ b/Library/Homebrew/test/system_command_result_spec.rb
@@ -45,7 +45,7 @@ describe SystemCommand::Result do
   end
 
   describe "#plist" do
-    subject { result.plist }
+    subject(:result_plist) { result.plist }
 
     let(:output_array) { [[:stdout, stdout]] }
     let(:garbage) {
@@ -116,7 +116,7 @@ describe SystemCommand::Result do
       }
 
       it "ignores garbage" do
-        expect(subject["system-entities"].length).to eq(3)
+        expect(result_plist["system-entities"].length).to eq(3)
       end
 
       context "when verbose" do
@@ -125,7 +125,7 @@ describe SystemCommand::Result do
         end
 
         it "warns about garbage" do
-          expect { subject }
+          expect { result_plist }
             .to output(a_string_containing(garbage)).to_stderr
         end
       end
@@ -140,7 +140,7 @@ describe SystemCommand::Result do
       }
 
       it "ignores garbage" do
-        expect(subject["system-entities"].length).to eq(3)
+        expect(result_plist["system-entities"].length).to eq(3)
       end
 
       context "when verbose" do
@@ -149,7 +149,7 @@ describe SystemCommand::Result do
         end
 
         it "warns about garbage" do
-          expect { subject }
+          expect { result_plist }
             .to output(a_string_containing(garbage)).to_stderr
         end
       end
@@ -159,9 +159,9 @@ describe SystemCommand::Result do
       let(:stdout) { plist }
 
       it "successfully parses it" do
-        expect(subject.keys).to eq(["system-entities"])
-        expect(subject["system-entities"].length).to eq(3)
-        expect(subject["system-entities"].map { |e| e["dev-entry"] })
+        expect(result_plist.keys).to eq(["system-entities"])
+        expect(result_plist["system-entities"].length).to eq(3)
+        expect(result_plist["system-entities"].map { |e| e["dev-entry"] })
           .to eq(["/dev/disk3s1", "/dev/disk3", "/dev/disk3s2"])
       end
     end
@@ -170,7 +170,7 @@ describe SystemCommand::Result do
       let(:stdout) { "" }
 
       it "returns nil" do
-        expect(subject).to be nil
+        expect(result_plist).to be nil
       end
     end
   end
diff --git a/Library/Homebrew/test/tab_spec.rb b/Library/Homebrew/test/tab_spec.rb
index 355a1c1838..ed99ddf8d1 100644
--- a/Library/Homebrew/test/tab_spec.rb
+++ b/Library/Homebrew/test/tab_spec.rb
@@ -19,7 +19,7 @@ describe Tab do
     end
   end
 
-  subject {
+  subject(:tab) {
     described_class.new(
       "homebrew_version"     => HOMEBREW_VERSION,
       "used_options"         => used_options.as_flags,
@@ -79,15 +79,15 @@ describe Tab do
   end
 
   specify "#include?" do
-    expect(subject).to include("with-foo")
-    expect(subject).to include("without-bar")
+    expect(tab).to include("with-foo")
+    expect(tab).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")
+    expect(tab).to be_built_with("foo")
+    expect(tab).to be_built_with("qux")
+    expect(tab).not_to be_built_with("bar")
+    expect(tab).not_to be_built_with("baz")
   end
 
   specify "#parsed_homebrew_version" do
@@ -146,16 +146,16 @@ describe Tab do
   end
 
   specify "#cxxstdlib" do
-    expect(subject.cxxstdlib.compiler).to eq(:clang)
-    expect(subject.cxxstdlib.type).to eq(:libcxx)
+    expect(tab.cxxstdlib.compiler).to eq(:clang)
+    expect(tab.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
+    expect(tab.HEAD).to eq(TEST_SHA1)
+    expect(tab.tap.name).to eq("homebrew/core")
+    expect(tab.time).to eq(time)
+    expect(tab).not_to be_built_as_bottle
+    expect(tab).to be_poured_from_bottle
   end
 
   describe "::from_file" do
@@ -286,19 +286,19 @@ describe Tab do
   end
 
   describe "::for_keg" do
-    subject { described_class.for_keg(f.prefix) }
+    subject(:tab_for_keg) { 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)
+      expect(tab_for_keg.tabfile).to eq(f_tab_path)
     end
 
     it "can create a Tab for a non-existent Keg" do
       f.prefix.mkpath
 
-      expect(subject.tabfile).to eq(f_tab_path)
+      expect(tab_for_keg.tabfile).to eq(f_tab_path)
     end
   end
 
@@ -359,27 +359,27 @@ describe Tab do
   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.head_version).to eq(subject.head_version)
-    expect(tab.source["path"]).to eq(subject.source["path"])
+    json_tab = described_class.new(JSON.parse(tab.to_json))
+    expect(json_tab.used_options.sort).to eq(tab.used_options.sort)
+    expect(json_tab.unused_options.sort).to eq(tab.unused_options.sort)
+    expect(json_tab.built_as_bottle).to eq(tab.built_as_bottle)
+    expect(json_tab.poured_from_bottle).to eq(tab.poured_from_bottle)
+    expect(json_tab.changed_files).to eq(tab.changed_files)
+    expect(json_tab.tap).to eq(tab.tap)
+    expect(json_tab.spec).to eq(tab.spec)
+    expect(json_tab.time).to eq(tab.time)
+    expect(json_tab.HEAD).to eq(tab.HEAD)
+    expect(json_tab.compiler).to eq(tab.compiler)
+    expect(json_tab.stdlib).to eq(tab.stdlib)
+    expect(json_tab.runtime_dependencies).to eq(tab.runtime_dependencies)
+    expect(json_tab.stable_version).to eq(tab.stable_version)
+    expect(json_tab.head_version).to eq(tab.head_version)
+    expect(json_tab.source["path"]).to eq(tab.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)
+    remapped_options = described_class.remap_deprecated_options(deprecated_options, tab.used_options)
     expect(remapped_options).to include(Option.new("without-bar"))
     expect(remapped_options).to include(Option.new("with-foo-new"))
   end
diff --git a/Library/Homebrew/test/tap_spec.rb b/Library/Homebrew/test/tap_spec.rb
index 9a108ec90d..06288eb633 100644
--- a/Library/Homebrew/test/tap_spec.rb
+++ b/Library/Homebrew/test/tap_spec.rb
@@ -5,7 +5,7 @@ describe Tap do
   alias_matcher :have_formula_file, :be_formula_file
   alias_matcher :have_custom_remote, :be_custom_remote
 
-  subject { described_class.new("Homebrew", "foo") }
+  subject(:homebrew_foo_tap) { described_class.new("Homebrew", "foo") }
 
   let(:path) { Tap::TAP_DIRECTORY/"homebrew/homebrew-foo" }
   let(:formula_file) { path/"Formula/foo.rb" }
@@ -131,13 +131,13 @@ describe Tap do
   end
 
   specify "attributes" do
-    expect(subject.user).to eq("Homebrew")
-    expect(subject.repo).to eq("foo")
-    expect(subject.name).to eq("homebrew/foo")
-    expect(subject.path).to eq(path)
-    expect(subject).to be_installed
-    expect(subject).to be_official
-    expect(subject).not_to be_a_core_tap
+    expect(homebrew_foo_tap.user).to eq("Homebrew")
+    expect(homebrew_foo_tap.repo).to eq("foo")
+    expect(homebrew_foo_tap.name).to eq("homebrew/foo")
+    expect(homebrew_foo_tap.path).to eq(path)
+    expect(homebrew_foo_tap).to be_installed
+    expect(homebrew_foo_tap).to be_official
+    expect(homebrew_foo_tap).not_to be_a_core_tap
   end
 
   specify "#issues_url" do
@@ -150,7 +150,7 @@ describe Tap do
              "https://github.com/someone/homebrew-foo"
     end
     expect(t.issues_url).to eq("https://github.com/someone/homebrew-foo/issues")
-    expect(subject.issues_url).to eq("https://github.com/Homebrew/homebrew-foo/issues")
+    expect(homebrew_foo_tap.issues_url).to eq("https://github.com/Homebrew/homebrew-foo/issues")
 
     (Tap::TAP_DIRECTORY/"someone/homebrew-no-git").mkpath
     expect(described_class.new("someone", "no-git").issues_url).to be nil
@@ -161,29 +161,29 @@ describe Tap do
   specify "files" do
     setup_tap_files
 
-    expect(subject.formula_files).to eq([formula_file])
-    expect(subject.formula_names).to eq(["homebrew/foo/foo"])
-    expect(subject.alias_files).to eq([alias_file])
-    expect(subject.aliases).to eq(["homebrew/foo/bar"])
-    expect(subject.alias_table).to eq("homebrew/foo/bar" => "homebrew/foo/foo")
-    expect(subject.alias_reverse_table).to eq("homebrew/foo/foo" => ["homebrew/foo/bar"])
-    expect(subject.formula_renames).to eq("oldname" => "foo")
-    expect(subject.tap_migrations).to eq("removed-formula" => "homebrew/foo")
-    expect(subject.command_files).to eq([cmd_file])
-    expect(subject.to_hash).to be_kind_of(Hash)
-    expect(subject).to have_formula_file(formula_file)
-    expect(subject).to have_formula_file("Formula/foo.rb")
-    expect(subject).not_to have_formula_file("bar.rb")
-    expect(subject).not_to have_formula_file("Formula/baz.sh")
+    expect(homebrew_foo_tap.formula_files).to eq([formula_file])
+    expect(homebrew_foo_tap.formula_names).to eq(["homebrew/foo/foo"])
+    expect(homebrew_foo_tap.alias_files).to eq([alias_file])
+    expect(homebrew_foo_tap.aliases).to eq(["homebrew/foo/bar"])
+    expect(homebrew_foo_tap.alias_table).to eq("homebrew/foo/bar" => "homebrew/foo/foo")
+    expect(homebrew_foo_tap.alias_reverse_table).to eq("homebrew/foo/foo" => ["homebrew/foo/bar"])
+    expect(homebrew_foo_tap.formula_renames).to eq("oldname" => "foo")
+    expect(homebrew_foo_tap.tap_migrations).to eq("removed-formula" => "homebrew/foo")
+    expect(homebrew_foo_tap.command_files).to eq([cmd_file])
+    expect(homebrew_foo_tap.to_hash).to be_kind_of(Hash)
+    expect(homebrew_foo_tap).to have_formula_file(formula_file)
+    expect(homebrew_foo_tap).to have_formula_file("Formula/foo.rb")
+    expect(homebrew_foo_tap).not_to have_formula_file("bar.rb")
+    expect(homebrew_foo_tap).not_to have_formula_file("Formula/baz.sh")
   end
 
   describe "#remote" do
     it "returns the remote URL" do
       setup_git_repo
 
-      expect(subject.remote).to eq("https://github.com/Homebrew/homebrew-foo")
+      expect(homebrew_foo_tap.remote).to eq("https://github.com/Homebrew/homebrew-foo")
       expect { described_class.new("Homebrew", "bar").remote }.to raise_error(TapUnavailableError)
-      expect(subject).not_to have_custom_remote
+      expect(homebrew_foo_tap).not_to have_custom_remote
 
       services_tap = described_class.new("Homebrew", "services")
       services_tap.path.mkpath
@@ -195,13 +195,13 @@ describe Tap do
     end
 
     it "returns nil if the Tap is not a Git repository" do
-      expect(subject.remote).to be nil
+      expect(homebrew_foo_tap.remote).to be nil
     end
 
     it "returns nil if Git is not available" do
       setup_git_repo
       allow(Utils::Git).to receive(:available?).and_return(false)
-      expect(subject.remote).to be nil
+      expect(homebrew_foo_tap.remote).to be nil
     end
   end
 
@@ -209,15 +209,15 @@ describe Tap do
     touch path/"README"
     setup_git_repo
 
-    expect(subject.git_head).to eq("0453e16c8e3fac73104da50927a86221ca0740c2")
-    expect(subject.git_short_head).to eq("0453")
-    expect(subject.git_last_commit).to match(/\A\d+ .+ ago\Z/)
-    expect(subject.git_last_commit_date).to eq("2017-01-22")
+    expect(homebrew_foo_tap.git_head).to eq("0453e16c8e3fac73104da50927a86221ca0740c2")
+    expect(homebrew_foo_tap.git_short_head).to eq("0453")
+    expect(homebrew_foo_tap.git_last_commit).to match(/\A\d+ .+ ago\Z/)
+    expect(homebrew_foo_tap.git_last_commit_date).to eq("2017-01-22")
   end
 
   specify "#private?" do
     skip "HOMEBREW_GITHUB_API_TOKEN is required" unless GitHub.api_credentials
-    expect(subject).to be_private
+    expect(homebrew_foo_tap).to be_private
   end
 
   describe "#install" do
@@ -232,7 +232,7 @@ describe Tap do
       setup_git_repo
       already_tapped_tap = described_class.new("Homebrew", "foo")
       expect(already_tapped_tap).to be_installed
-      right_remote = subject.remote
+      right_remote = homebrew_foo_tap.remote
       expect { already_tapped_tap.install clone_target: right_remote }.to raise_error(TapAlreadyTappedError)
     end
 
@@ -240,7 +240,7 @@ describe Tap do
       setup_git_repo
       already_tapped_tap = described_class.new("Homebrew", "foo")
       expect(already_tapped_tap).to be_installed
-      wrong_remote = "#{subject.remote}-oops"
+      wrong_remote = "#{homebrew_foo_tap.remote}-oops"
       expect {
         already_tapped_tap.install clone_target: wrong_remote
       }.to raise_error(TapRemoteMismatchError)
@@ -297,7 +297,7 @@ describe Tap do
 
     tap = described_class.new("Homebrew", "bar")
 
-    tap.install clone_target: subject.path/".git"
+    tap.install clone_target: homebrew_foo_tap.path/".git"
 
     expect(tap).to be_installed
     expect(HOMEBREW_PREFIX/"share/man/man1/brew-tap-cmd.1").to be_a_file
@@ -322,7 +322,7 @@ describe Tap do
     setup_git_repo
     setup_completion link: true
     tap = described_class.new("NotHomebrew", "baz")
-    tap.install clone_target: subject.path/".git"
+    tap.install clone_target: homebrew_foo_tap.path/".git"
     (HOMEBREW_PREFIX/"share/man/man1/brew-tap-cmd.1").delete
     (HOMEBREW_PREFIX/"etc/bash_completion.d/brew-tap-cmd").delete
     (HOMEBREW_PREFIX/"share/zsh/site-functions/_brew-tap-cmd").delete
@@ -343,7 +343,7 @@ describe Tap do
     setup_git_repo
     setup_completion link: false
     tap = described_class.new("NotHomebrew", "baz")
-    tap.install clone_target: subject.path/".git"
+    tap.install clone_target: homebrew_foo_tap.path/".git"
     (HOMEBREW_PREFIX/"share/man/man1/brew-tap-cmd.1").delete
     tap.link_completions_and_manpages
     expect(HOMEBREW_PREFIX/"share/man/man1/brew-tap-cmd.1").to be_a_file
@@ -361,7 +361,7 @@ describe Tap do
     setup_git_repo
     setup_completion link: false
     tap = described_class.new("Homebrew", "baz")
-    tap.install clone_target: subject.path/".git"
+    tap.install clone_target: homebrew_foo_tap.path/".git"
     (HOMEBREW_PREFIX/"share/man/man1/brew-tap-cmd.1").delete
     (HOMEBREW_PREFIX/"etc/bash_completion.d/brew-tap-cmd").delete
     (HOMEBREW_PREFIX/"share/zsh/site-functions/_brew-tap-cmd").delete
@@ -380,11 +380,11 @@ describe Tap do
   specify "#config" do
     setup_git_repo
 
-    expect(subject.config["foo"]).to be nil
-    subject.config["foo"] = "bar"
-    expect(subject.config["foo"]).to eq("bar")
-    subject.config["foo"] = nil
-    expect(subject.config["foo"]).to be nil
+    expect(homebrew_foo_tap.config["foo"]).to be nil
+    homebrew_foo_tap.config["foo"] = "bar"
+    expect(homebrew_foo_tap.config["foo"]).to eq("bar")
+    homebrew_foo_tap.config["foo"] = nil
+    expect(homebrew_foo_tap.config["foo"]).to be nil
   end
 
   describe "#each" do
@@ -399,7 +399,7 @@ describe Tap do
         setup_tap_files
 
         expected_result = { "oldname" => "foo" }
-        expect(subject.formula_renames).to eq expected_result
+        expect(homebrew_foo_tap.formula_renames).to eq expected_result
       end
     end
 
@@ -408,7 +408,7 @@ describe Tap do
         setup_tap_files
 
         expected_result = { "removed-formula" => "homebrew/foo" }
-        expect(subject.tap_migrations).to eq expected_result
+        expect(homebrew_foo_tap.tap_migrations).to eq expected_result
       end
     end
 
@@ -420,7 +420,7 @@ describe Tap do
           formula_list: ["foo", "bar"],
           formula_hash: { "foo" => "foo1", "bar" => "bar1" },
         }
-        expect(subject.audit_exceptions).to eq expected_result
+        expect(homebrew_foo_tap.audit_exceptions).to eq expected_result
       end
     end
 
@@ -432,7 +432,7 @@ describe Tap do
           formula_list: ["foo", "bar"],
           formula_hash: { "foo" => "foo1", "bar" => "bar1" },
         }
-        expect(subject.style_exceptions).to eq expected_result
+        expect(homebrew_foo_tap.style_exceptions).to eq expected_result
       end
     end
 
@@ -448,33 +448,35 @@ describe Tap do
             "exclude_packages" => ["baz"],
           },
         }
-        expect(subject.pypi_formula_mappings).to eq expected_result
+        expect(homebrew_foo_tap.pypi_formula_mappings).to eq expected_result
       end
     end
   end
 end
 
 describe CoreTap do
+  subject(:core_tap) { described_class.new }
+
   specify "attributes" do
-    expect(subject.user).to eq("Homebrew")
-    expect(subject.repo).to eq("core")
-    expect(subject.name).to eq("homebrew/core")
-    expect(subject.command_files).to eq([])
-    expect(subject).to be_installed
-    expect(subject).not_to be_pinned
-    expect(subject).to be_official
-    expect(subject).to be_a_core_tap
+    expect(core_tap.user).to eq("Homebrew")
+    expect(core_tap.repo).to eq("core")
+    expect(core_tap.name).to eq("homebrew/core")
+    expect(core_tap.command_files).to eq([])
+    expect(core_tap).to be_installed
+    expect(core_tap).not_to be_pinned
+    expect(core_tap).to be_official
+    expect(core_tap).to be_a_core_tap
   end
 
   specify "forbidden operations" do
-    expect { subject.uninstall }.to raise_error(RuntimeError)
-    expect { subject.pin }.to raise_error(RuntimeError)
-    expect { subject.unpin }.to raise_error(RuntimeError)
+    expect { core_tap.uninstall }.to raise_error(RuntimeError)
+    expect { core_tap.pin }.to raise_error(RuntimeError)
+    expect { core_tap.unpin }.to raise_error(RuntimeError)
   end
 
   specify "files" do
     path = Tap::TAP_DIRECTORY/"homebrew/homebrew-core"
-    formula_file = subject.formula_dir/"foo.rb"
+    formula_file = core_tap.formula_dir/"foo.rb"
     formula_file.write <<~RUBY
       class Foo < Formula
         url "https://brew.sh/foo-1.0.tar.gz"
@@ -493,21 +495,21 @@ describe CoreTap do
       (path/file).write formula_list_file_json
     end
 
-    alias_file = subject.alias_dir/"bar"
+    alias_file = core_tap.alias_dir/"bar"
     alias_file.parent.mkpath
     ln_s formula_file, alias_file
 
-    expect(subject.formula_files).to eq([formula_file])
-    expect(subject.formula_names).to eq(["foo"])
-    expect(subject.alias_files).to eq([alias_file])
-    expect(subject.aliases).to eq(["bar"])
-    expect(subject.alias_table).to eq("bar" => "foo")
-    expect(subject.alias_reverse_table).to eq("foo" => ["bar"])
+    expect(core_tap.formula_files).to eq([formula_file])
+    expect(core_tap.formula_names).to eq(["foo"])
+    expect(core_tap.alias_files).to eq([alias_file])
+    expect(core_tap.aliases).to eq(["bar"])
+    expect(core_tap.alias_table).to eq("bar" => "foo")
+    expect(core_tap.alias_reverse_table).to eq("foo" => ["bar"])
 
-    expect(subject.formula_renames).to eq formula_list_file_contents
-    expect(subject.tap_migrations).to eq formula_list_file_contents
-    expect(subject.audit_exceptions).to eq({ formula_list: formula_list_file_contents })
-    expect(subject.style_exceptions).to eq({ formula_hash: formula_list_file_contents })
-    expect(subject.pypi_formula_mappings).to eq formula_list_file_contents
+    expect(core_tap.formula_renames).to eq formula_list_file_contents
+    expect(core_tap.tap_migrations).to eq formula_list_file_contents
+    expect(core_tap.audit_exceptions).to eq({ formula_list: formula_list_file_contents })
+    expect(core_tap.style_exceptions).to eq({ formula_hash: formula_list_file_contents })
+    expect(core_tap.pypi_formula_mappings).to eq formula_list_file_contents
   end
 end
diff --git a/Library/Homebrew/test/utils_spec.rb b/Library/Homebrew/test/utils_spec.rb
index efaf326603..380b1d3803 100644
--- a/Library/Homebrew/test/utils_spec.rb
+++ b/Library/Homebrew/test/utils_spec.rb
@@ -28,14 +28,14 @@ describe "globally-scoped helper methods" do
   end
 
   describe "#pretty_installed" do
-    subject { pretty_installed("foo") }
+    subject(:pretty_installed_output) { pretty_installed("foo") }
 
     context "when $stdout is a TTY" do
       before { allow($stdout).to receive(:tty?).and_return(true) }
 
       context "with HOMEBREW_NO_EMOJI unset" do
         it "returns a string with a colored checkmark" do
-          expect(subject)
+          expect(pretty_installed_output)
             .to match(/#{esc 1}foo #{esc 32}✔#{esc 0}/)
         end
       end
@@ -44,7 +44,7 @@ describe "globally-scoped helper methods" do
         before { ENV["HOMEBREW_NO_EMOJI"] = "1" }
 
         it "returns a string with colored info" do
-          expect(subject)
+          expect(pretty_installed_output)
             .to match(/#{esc 1}foo \(installed\)#{esc 0}/)
         end
       end
@@ -54,20 +54,20 @@ describe "globally-scoped helper methods" do
       before { allow($stdout).to receive(:tty?).and_return(false) }
 
       it "returns plain text" do
-        expect(subject).to eq("foo")
+        expect(pretty_installed_output).to eq("foo")
       end
     end
   end
 
   describe "#pretty_uninstalled" do
-    subject { pretty_uninstalled("foo") }
+    subject(:pretty_uninstalled_output) { pretty_uninstalled("foo") }
 
     context "when $stdout is a TTY" do
       before { allow($stdout).to receive(:tty?).and_return(true) }
 
       context "with HOMEBREW_NO_EMOJI unset" do
         it "returns a string with a colored checkmark" do
-          expect(subject)
+          expect(pretty_uninstalled_output)
             .to match(/#{esc 1}foo #{esc 31}✘#{esc 0}/)
         end
       end
@@ -76,7 +76,7 @@ describe "globally-scoped helper methods" do
         before { ENV["HOMEBREW_NO_EMOJI"] = "1" }
 
         it "returns a string with colored info" do
-          expect(subject)
+          expect(pretty_uninstalled_output)
             .to match(/#{esc 1}foo \(uninstalled\)#{esc 0}/)
         end
       end
@@ -86,7 +86,7 @@ describe "globally-scoped helper methods" do
       before { allow($stdout).to receive(:tty?).and_return(false) }
 
       it "returns plain text" do
-        expect(subject).to eq("foo")
+        expect(pretty_uninstalled_output).to eq("foo")
       end
     end
   end
diff --git a/Library/Homebrew/test/version_spec.rb b/Library/Homebrew/test/version_spec.rb
index d828d766ed..2df4494387 100644
--- a/Library/Homebrew/test/version_spec.rb
+++ b/Library/Homebrew/test/version_spec.rb
@@ -72,14 +72,14 @@ end
 
 describe Version do
   describe "::NULL_TOKEN" do
-    subject { described_class::NULL_TOKEN }
+    subject(:null_version) { described_class::NULL_TOKEN }
 
     specify "#inspect" do
-      expect(subject.inspect).to eq("#<Version::NullToken>")
+      expect(null_version.inspect).to eq("#<Version::NullToken>")
     end
 
     it "is equal to itself" do
-      expect(subject).to be == described_class::NULL_TOKEN
+      expect(null_version).to be == described_class::NULL_TOKEN
     end
   end