Unify (mostly) Homebrew code style

Make the Homebrew/cask and Homebrew/homebrew-core style more closely
match the rest of Homebrew.

To accomplish this:
- Run `brew cask style` to ensure we don't break style there when
  making changes or upgrading RuboCop in Homebrew/brew.
- Fix the HomepageMatchesUrl cop to better handle weird input.
- Remove the now unneeded `.rubocop_shared.yml`
- Fix the cask fixtures with `brew cask style --fix`.
- Share more style between Homebrew/brew, casks and formulae.

.github/workflows/tests.yml

@@ -103,6 +103,9 @@ jobs:
         if [ "$RUNNER_OS" = "macOS" ]; then
           brew tap homebrew/cask
           brew update-reset Library/Taps/homebrew/homebrew-cask
+
+          # don't care about `brew cask style` here.
+          brew untap adoptopenjdk/openjdk
         else
           # Fix permissions for 'brew tests'
           sudo chmod -R g-w,o-w /home/linuxbrew /home/runner /opt
@@ -159,6 +162,10 @@ jobs:
     - name: Run brew style on official taps
       run: brew style --display-cop-names homebrew/bundle homebrew/services homebrew/test-bot
 
+    - name: Run brew cask style
+      if: matrix.os == 'macOS-latest'
+      run: brew cask style
+
     - name: Run vale for docs linting
       run: |
         brew install vale

Library/.rubocop.yml

-inherit_from: ./.rubocop_shared.yml
+# TODO: Try getting more rules in sync.
+
+require: ./Homebrew/rubocops.rb
+
+AllCops:
+  TargetRubyVersion: 2.6
+  DisplayCopNames: false
+  # enable all pending rubocops
+  NewCops: enable
 
 # enable all formulae audits
 FormulaAudit:
@@ -8,9 +16,108 @@ FormulaAudit:
 FormulaAuditStrict:
   Enabled: true
 
-# enable all pending rubocops
-AllCops:
-  NewCops: enable
+# Use `<<~` for heredocs.
+Layout/HeredocIndentation:
+  Enabled: true
+
+# Not useful in casks and formulae.
+Metrics/BlockLength:
+  Enabled: false
+
+# Keyword arguments don't have the same readability
+# problems as normal parameters.
+Metrics/ParameterLists:
+  CountKeywordArgs: false
+
+# Implicitly allow EOS as we use it everywhere.
+Naming/HeredocDelimiterNaming:
+  ForbiddenDelimiters:
+    - END, EOD, EOF
+
+# Allow dashes in filenames.
+Naming/FileName:
+  Regex: !ruby/regexp /^[\w\@\-\+\.]+(\.rb)?$/
+
+# Both styles are used depending on context,
+# e.g. `sha256` and `something_countable_1`.
+Naming/VariableNumber:
+  Enabled: false
+
+# Avoid leaking resources.
+Style/AutoResourceCleanup:
+  Enabled: true
+
+# This makes these a little more obvious.
+Style/BarePercentLiterals:
+  EnforcedStyle: percent_q
+
+# Use consistent style for better readability.
+Style/CollectionMethods:
+  Enabled: true
+
+# Prefer tokens with type annotations for consistency
+# between formatting numbers and strings.
+Style/FormatStringToken:
+  EnforcedStyle: annotated
+
+# autocorrectable and more readable
+Style/HashEachMethods:
+  Enabled: true
+Style/HashTransformKeys:
+  Enabled: true
+Style/HashTransformValues:
+  Enabled: true
+
+# Enabled now LineLength is lowish.
+Style/IfUnlessModifier:
+  Enabled: true
+
+# Only use this for numbers >= `1_000_000`.
+Style/NumericLiterals:
+  MinDigits: 7
+  Strict: true
+
+# Zero-prefixed octal literals are widely used and understood.
+Style/NumericLiteralPrefix:
+  EnforcedOctalStyle: zero_only
+
+# Rescuing `StandardError` is an understood default.
+Style/RescueStandardError:
+  EnforcedStyle: implicit
+
+# Returning `nil` is unnecessary.
+Style/ReturnNil:
+  Enabled: true
+
+# We have no use for using `warn` because we
+# are calling Ruby with warnings disabled.
+Style/StderrPuts:
+  Enabled: false
+
+# Use consistent method names.
+Style/StringMethods:
+  Enabled: true
+
+# An array of symbols is more readable than a symbol array
+# and also allows for easier grepping.
+Style/SymbolArray:
+  EnforcedStyle: brackets
+
+# Trailing commas make diffs nicer.
+Style/TrailingCommaInArguments:
+  EnforcedStyleForMultiline: comma
+Style/TrailingCommaInArrayLiteral:
+  EnforcedStyleForMultiline: comma
+Style/TrailingCommaInHashLiteral:
+  EnforcedStyleForMultiline: comma
+
+# Does not hinder readability, so might as well enable it.
+Performance/CaseWhenSplat:
+  Enabled: true
+
+# Makes code less readable for minor performance increases.
+Performance/Caller:
+  Enabled: false
 
 # don't allow cops to be disabled in formulae
 Style/DisableCopsWithinSourceCodeDirective:
@@ -54,6 +161,7 @@ Lint/AmbiguousRegexpLiteral:
 Lint/ParenthesesAsGroupedExpression:
   Enabled: false
 
+
 # most metrics don't make sense to apply for formulae/taps
 Metrics/AbcSize:
   Enabled: false
@@ -72,7 +180,15 @@ Metrics/PerceivedComplexity:
 Layout/LineLength:
   Max: 118
   # ignore manpage comments and long single-line strings
-  IgnoredPatterns: ['#: ', ' url "', ' mirror "', ' plist_options :']
+  IgnoredPatterns: ['#: ', ' url "', ' mirror "', ' plist_options ',
+                    ' appcast "', ' executable: "', '#{version.',
+                    ' "~/Library/Application Support/', '"~/Library/Caches/', '"~/Application Support',
+                    ' was verified as official when first introduced to the cask']
+
+# TODO: remove this when possible.
+Style/ClassVars:
+  Exclude:
+  - '**/developer/bin/*'
 
 # most of our APIs are internal so don't require docs
 Style/Documentation:
@@ -82,26 +198,18 @@ Style/Documentation:
 Style/FrozenStringLiteralComment:
   Enabled: false
 
+# TODO: remove this when possible.
+Style/GlobalVars:
+  Exclude:
+  - '**/developer/bin/*'
+
 # potential for errors in formulae too high with this
 Style/GuardClause:
   Enabled: false
 
-# depends_on a: :b looks weird in formulae.
+# avoid hash rockets where possible
 Style/HashSyntax:
-  EnforcedStyle: hash_rockets
-  Exclude:
-  - '**/Guardfile'
-  - '**/cmd/**/*.rb'
-  - '**/lib/**/*.rb'
-  - '**/spec/**/*.rb'
-
-# autocorrectable and more readable
-Style/HashEachMethods:
-  Enabled: true
-Style/HashTransformKeys:
-  Enabled: true
-Style/HashTransformValues:
-  Enabled: true
+  EnforcedStyle: ruby19
 
 # ruby style guide favorite
 Style/StringLiterals:
@@ -118,3 +226,11 @@ Style/TernaryParentheses:
 # a bit confusing to non-Rubyists but useful for longer arrays
 Style/WordArray:
   MinSize: 4
+
+# would rather freeze too much than too little
+Style/MutableConstant:
+  EnforcedStyle: strict
+
+# unused keyword arguments improve APIs
+Lint/UnusedMethodArgument:
+  AllowUnusedKeywordArguments: true

Library/.rubocop_cask.yml

-inherit_from: ./.rubocop_shared.yml
+inherit_from: ./Homebrew/.rubocop.yml
 
 Cask/HomepageMatchesUrl:
   Description: 'Ensure that the homepage and url match, otherwise add a comment. More info at https://github.com/Homebrew/homebrew-cask/blob/HEAD/doc/cask_language_reference/stanzas/url.md#when-url-and-homepage-hostnames-differ-add-a-comment'
   Enabled: true
-  Exclude:
-  - '**/test/support/fixtures/cask/Casks/**/*.rb'
 
 Cask/HomepageUrlTrailingSlash:
   Description: 'Ensure that the homepage url has a slash after the domain name.'
@@ -22,44 +20,6 @@ Cask/StanzaOrder:
   Description: 'Ensure that cask stanzas are sorted correctly. More info at https://github.com/Homebrew/homebrew-cask/blob/HEAD/CONTRIBUTING.md#stanza-order'
   Enabled: true
 
-Layout/HashAlignment:
-  EnforcedHashRocketStyle: table
-  EnforcedColonStyle: table
-
-Layout/FirstArrayElementIndentation:
-  EnforcedStyle: align_brackets
-
-Layout/FirstHashElementIndentation:
-  EnforcedStyle: align_braces
-
-# Casks often contain long URLs and file paths.
-Layout/LineLength:
-  Enabled: false
-
-# Casks don't need documentation.
-Style/Documentation:
-  Enabled: false
-
-# These would only be distracting in casks.
+# don't want this for casks but re-enabled for Library/Homebrew
 Style/FrozenStringLiteralComment:
-  EnforcedStyle: never
-
-# Don't use hash rockets.
-Style/HashSyntax:
-  EnforcedStyle: ruby19_no_mixed_keys
-
-# This is more readable when the regex contains slashes.
-Style/RegexpLiteral:
-  EnforcedStyle: percent_r
-
-# Use consistent style for all arrays.
-Style/WordArray:
-  EnforcedStyle: brackets
-
-# This makes multi-line arrays more readable and alignable.
-Layout/FirstArrayElementLineBreak:
-  Enabled: true
-
-# This makes multi-line hashes more readable and alignable.
-Layout/FirstHashElementLineBreak:
-  Enabled: true
+  Enabled: false

Library/.rubocop_shared.yml

-# TODO: Try getting more rules in sync.
-
-require: ./Homebrew/rubocops.rb
-
-AllCops:
-  TargetRubyVersion: 2.6
-  DisplayCopNames: false
-
-# Use `<<~` for heredocs.
-Layout/HeredocIndentation:
-  Enabled: true
-
-# Not useful in casks and formulae.
-Metrics/BlockLength:
-  Enabled: false
-
-# Keyword arguments don't have the same readability
-# problems as normal parameters.
-Metrics/ParameterLists:
-  CountKeywordArgs: false
-
-# Implicitly allow EOS as we use it everywhere.
-Naming/HeredocDelimiterNaming:
-  ForbiddenDelimiters:
-    - END, EOD, EOF
-
-# Allow dashes in filenames.
-Naming/FileName:
-  Regex: !ruby/regexp /^[\w\@\-\+\.]+(\.rb)?$/
-
-# Both styles are used depending on context,
-# e.g. `sha256` and `something_countable_1`.
-Naming/VariableNumber:
-  Enabled: false
-
-# Avoid leaking resources.
-Style/AutoResourceCleanup:
-  Enabled: true
-
-# This makes these a little more obvious.
-Style/BarePercentLiterals:
-  EnforcedStyle: percent_q
-
-# Use consistent style for better readability.
-Style/CollectionMethods:
-  Enabled: true
-
-# Prefer tokens with type annotations for consistency
-# between formatting numbers and strings.
-Style/FormatStringToken:
-  EnforcedStyle: annotated
-
-# autocorrectable and more readable
-Style/HashEachMethods:
-  Enabled: true
-Style/HashTransformKeys:
-  Enabled: true
-Style/HashTransformValues:
-  Enabled: true
-
-# Enabled now LineLength is lowish.
-Style/IfUnlessModifier:
-  Enabled: true
-
-# Only use this for numbers >= `1_000_000`.
-Style/NumericLiterals:
-  MinDigits: 7
-  Strict: true
-
-# Zero-prefixed octal literals are widely used and understood.
-Style/NumericLiteralPrefix:
-  EnforcedOctalStyle: zero_only
-
-# Rescuing `StandardError` is an understood default.
-Style/RescueStandardError:
-  EnforcedStyle: implicit
-
-# Returning `nil` is unnecessary.
-Style/ReturnNil:
-  Enabled: true
-
-# We have no use for using `warn` because we
-# are calling Ruby with warnings disabled.
-Style/StderrPuts:
-  Enabled: false
-
-# Use consistent method names.
-Style/StringMethods:
-  Enabled: true
-
-# An array of symbols is more readable than a symbol array
-# and also allows for easier grepping.
-Style/SymbolArray:
-  EnforcedStyle: brackets
-
-# Trailing commas make diffs nicer.
-Style/TrailingCommaInArguments:
-  EnforcedStyleForMultiline: comma
-Style/TrailingCommaInArrayLiteral:
-  EnforcedStyleForMultiline: comma
-Style/TrailingCommaInHashLiteral:
-  EnforcedStyleForMultiline: comma
-
-# Does not hinder readability, so might as well enable it.
-Performance/CaseWhenSplat:
-  Enabled: true
-
-# Makes code less readable for minor performance increases.
-Performance/Caller:
-  Enabled: false

Library/Homebrew/.rubocop.yml

@@ -6,7 +6,6 @@ AllCops:
     - 'Library/Homebrew/.simplecov'
   Exclude:
     - 'bin/*'
-    - '**/Casks/**/*'
     - '**/vendor/**/*'
 
 # messes up system formatting for formulae but good for Homebrew/brew
@@ -35,10 +34,6 @@ Lint/NestedMethodDefinition:
 Lint/ParenthesesAsGroupedExpression:
   Enabled: true
 
-# unused keyword arguments improve APIs
-Lint/UnusedMethodArgument:
-  AllowUnusedKeywordArguments: true
-
 # TODO: try to bring down all metrics maximums
 Metrics/AbcSize:
   Enabled: true
@@ -113,10 +108,7 @@ Style/BlockDelimiters:
 
 # don't group nicely documented or private attr_readers
 Style/AccessorGrouping:
-  Enabled: true
   Exclude:
-    - 'cask/cmd/internal_stanza.rb'
-    - 'cask/download.rb'
     - 'formula.rb'
     - 'formulary.rb'
     - 'migrator.rb'
@@ -124,11 +116,6 @@ Style/AccessorGrouping:
     - 'system_command.rb'
     - 'tap.rb'
 
-# https://github.com/rubocop-hq/rubocop/issues/8257
-Style/BisectedAttrAccessor:
-  Exclude:
-     - 'cask/url.rb'
-
 # document our public APIs
 Style/Documentation:
   Enabled: true
@@ -143,19 +130,9 @@ Style/DocumentationMethod:
 Style/FrozenStringLiteralComment:
   Enabled: true
   EnforcedStyle: always
+  Exclude:
+  - '**/Casks/**/*.rb'
 
 # so many of these in formulae but none in here
 Style/GuardClause:
   Enabled: true
-
-# hash-rockets preferred for formulae, a: 1 preferred here
-Style/HashSyntax:
-  EnforcedStyle: ruby19_no_mixed_keys
-
-# would rather freeze too much than too little
-Style/MutableConstant:
-  EnforcedStyle: strict
-
-# LineLength is low enough here to re-enable it.
-Style/IfUnlessModifier:
-  Enabled: true

Library/Homebrew/cask/cmd/internal_stanza.rb

@@ -32,12 +32,8 @@ module Cask
       option "--yaml",    :yaml,    false
       option "--inspect", :inspect, false
 
-      attr_accessor :format
-
+      attr_accessor :format, :stanza
       private :format, :format=
-
-      attr_accessor :stanza
-
       private :stanza, :stanza=
 
       def initialize(*)

Library/Homebrew/rubocops/cask/homepage_matches_url.rb

@@ -9,7 +9,7 @@ module RuboCop
       # or if it doesn't, checks if a comment in the form
       # `# example.com was verified as official when first introduced to the cask`
       # is present.
-      class HomepageMatchesUrl < Cop # rubocop:disable Metrics/ClassLength
+      class HomepageMatchesUrl < Cop
         extend Forwardable
         include CaskHelp
 
@@ -134,7 +134,13 @@ module RuboCop
 
         def url_match_homepage?(stanza)
           host = extract_url(stanza).downcase
-          host_uri = URI(remove_non_ascii(host))
+          host_uri = begin
+            URI(remove_non_ascii(host))
+          rescue URI::InvalidURIError
+            # Can't check if we can't parse.
+            return true
+          end
+
           host = if host.match?(/:\d/) && host_uri.port != 80
             "#{host_uri.host}:#{host_uri.port}"
           else

Library/Homebrew/test/cask/cmd/cat_spec.rb

@@ -10,14 +10,14 @@ describe Cask::Cmd::Cat, :cask do
   describe "given a basic Cask" do
     let(:basic_cask_content) {
       <<~RUBY
-        cask 'basic-cask' do
-          version '1.2.3'
-          sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+        cask "basic-cask" do
+          version "1.2.3"
+          sha256 "8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b"
 
-          url 'https://brew.sh/TestCask.dmg'
-          homepage 'https://brew.sh/'
+          url "https://brew.sh/TestCask.dmg"
+          homepage "https://brew.sh/"
 
-          app 'TestCask.app'
+          app "TestCask.app"
         end
       RUBY
     }

Library/Homebrew/test/cask/cmd/style_spec.rb

@@ -15,14 +15,16 @@ describe Cask::Cmd::Style, :cask do
 
     around do |example|
       FileUtils.ln_s HOMEBREW_LIBRARY_PATH, HOMEBREW_LIBRARY/"Homebrew"
+      FileUtils.ln_s HOMEBREW_LIBRARY_PATH.parent/".rubocop.yml", HOMEBREW_LIBRARY/".rubocop.yml"
       FileUtils.ln_s HOMEBREW_LIBRARY_PATH.parent/".rubocop_cask.yml", HOMEBREW_LIBRARY/".rubocop_cask.yml"
-      FileUtils.ln_s HOMEBREW_LIBRARY_PATH.parent/".rubocop_shared.yml", HOMEBREW_LIBRARY/".rubocop_shared.yml"
+      FileUtils.ln_s HOMEBREW_LIBRARY_PATH.parent/".rubocop_rspec.yml", HOMEBREW_LIBRARY/".rubocop_rspec.yml"
 
       example.run
     ensure
       FileUtils.rm_f HOMEBREW_LIBRARY/"Homebrew"
+      FileUtils.rm_f HOMEBREW_LIBRARY/".rubocop.yml"
       FileUtils.rm_f HOMEBREW_LIBRARY/".rubocop_cask.yml"
-      FileUtils.rm_f HOMEBREW_LIBRARY/".rubocop_shared.yml"
+      FileUtils.rm_f HOMEBREW_LIBRARY/".rubocop_rspec.yml"
     end
 
     before do

Library/Homebrew/test/style_spec.rb

@@ -6,13 +6,11 @@ describe Homebrew::Style do
   around do |example|
     FileUtils.ln_s HOMEBREW_LIBRARY_PATH, HOMEBREW_LIBRARY/"Homebrew"
     FileUtils.ln_s HOMEBREW_LIBRARY_PATH.parent/".rubocop.yml", HOMEBREW_LIBRARY/".rubocop.yml"
-    FileUtils.ln_s HOMEBREW_LIBRARY_PATH.parent/".rubocop_shared.yml", HOMEBREW_LIBRARY/".rubocop_shared.yml"
 
     example.run
   ensure
     FileUtils.rm_f HOMEBREW_LIBRARY/"Homebrew"
     FileUtils.rm_f HOMEBREW_LIBRARY/".rubocop.yml"
-    FileUtils.rm_f HOMEBREW_LIBRARY/".rubocop_shared.yml"
   end
 
   before do

Library/Homebrew/test/support/fixtures/cask/Casks/adobe-air.rb

-cask 'adobe-air' do
-  version '1.2.3'
-  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+cask "adobe-air" do
+  version "1.2.3"
+  sha256 "8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b"
 
-  url 'https://brew.sh/TestCask.dmg'
-  name 'Adobe Air'
-  homepage 'https://brew.sh/'
+  url "https://brew.sh/TestCask.dmg"
+  name "Adobe Air"
+  homepage "https://brew.sh/"
 
-  app 'TestCask.app'
+  app "TestCask.app"
 end

Library/Homebrew/test/support/fixtures/cask/Casks/adobe-illustrator.rb

-cask 'adobe-illustrator' do
-  version '1.2.3'
-  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+cask "adobe-illustrator" do
+  version "1.2.3"
+  sha256 "8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b"
 
-  url 'https://brew.sh/TestCask.dmg'
-  name 'Adobe Illustrator'
-  homepage 'https://brew.sh/'
+  url "https://brew.sh/TestCask.dmg"
+  name "Adobe Illustrator"
+  homepage "https://brew.sh/"
 
-  app 'TestCask.app'
+  app "TestCask.app"
 end

Library/Homebrew/test/support/fixtures/cask/Casks/appdir-interpolation.rb

-cask 'appdir-interpolation' do
-  version '2.61'
-  sha256 'e44ffa103fbf83f55c8d0b1bea309a43b2880798dae8620b1ee8da5e1095ec68'
+cask "appdir-interpolation" do
+  version "2.61"
+  sha256 "e44ffa103fbf83f55c8d0b1bea309a43b2880798dae8620b1ee8da5e1095ec68"
 
   url "file://#{TEST_FIXTURE_DIR}/cask/transmission-2.61.dmg"
-  homepage 'https://brew.sh/appdir-interpolation'
+  homepage "https://brew.sh/appdir-interpolation"
 
   binary "#{appdir}/some/path"
 end

Library/Homebrew/test/support/fixtures/cask/Casks/auto-updates.rb

-cask 'auto-updates' do
-  version '2.61'
-  sha256 '5633c3a0f2e572cbf021507dec78c50998b398c343232bdfc7e26221d0a5db4d'
+cask "auto-updates" do
+  version "2.61"
+  sha256 "5633c3a0f2e572cbf021507dec78c50998b398c343232bdfc7e26221d0a5db4d"
 
   url "file://#{TEST_FIXTURE_DIR}/cask/MyFancyApp.zip"
-  homepage 'https://brew.sh/MyFancyApp'
+  homepage "https://brew.sh/MyFancyApp"
 
   auto_updates true
 
-  app 'MyFancyApp/MyFancyApp.app'
+  app "MyFancyApp/MyFancyApp.app"
 end

Library/Homebrew/test/support/fixtures/cask/Casks/bad-checksum.rb

-cask 'bad-checksum' do
-  version '1.2.3'
-  sha256 'badbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadb'
+cask "bad-checksum" do
+  version "1.2.3"
+  sha256 "badbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadb"
 
   url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
-  homepage 'https://brew.sh/'
+  homepage "https://brew.sh/"
 
-  app 'Caffeine.app'
+  app "Caffeine.app"
 end

Library/Homebrew/test/support/fixtures/cask/Casks/bad-checksum2.rb

-cask 'bad-checksum2' do
-  version '1.2.3'
-  sha256 'badbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadb'
+cask "bad-checksum2" do
+  version "1.2.3"
+  sha256 "badbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadbadb"
 
   url "file://#{TEST_FIXTURE_DIR}/cask/container.tar.gz"
-  homepage 'https://brew.sh/container-tar-gz'
+  homepage "https://brew.sh/container-tar-gz"
 
-  app 'container'
+  app "container"
 end

Library/Homebrew/test/support/fixtures/cask/Casks/basic-cask.rb

-cask 'basic-cask' do
-  version '1.2.3'
-  sha256 '8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b'
+cask "basic-cask" do
+  version "1.2.3"
+  sha256 "8c62a2b791cf5f0da6066a0a4b6e85f62949cd60975da062df44adf887f4370b"
 
-  url 'https://brew.sh/TestCask.dmg'
-  homepage 'https://brew.sh/'
+  url "https://brew.sh/TestCask.dmg"
+  homepage "https://brew.sh/"
 
-  app 'TestCask.app'
+  app "TestCask.app"
 end

Library/Homebrew/test/support/fixtures/cask/Casks/booby-trap.rb

-cask 'booby-trap' do
-  version '0.0.7'
+cask "booby-trap" do
+  version "0.0.7"
 
   url do
     # to be lazily evaluated
-    raise 'Boom'
+    raise "Boom"
   end
 end

Library/Homebrew/test/support/fixtures/cask/Casks/compat/with-depends-on-macos-string.rb

-cask 'with-depends-on-macos-string' do
-  version '1.2.3'
-  sha256 '67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94'
+cask "with-depends-on-macos-string" do
+  version "1.2.3"
+  sha256 "67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94"
 
   url "file://#{TEST_FIXTURE_DIR}/cask/caffeine.zip"
-  homepage 'https://brew.sh/with-depends-on-macos-string'
+  homepage "https://brew.sh/with-depends-on-macos-string"
 
   depends_on macos: MacOS.version.to_s
 
-  app 'Caffeine.app'
+  app "Caffeine.app"
 end

Library/Homebrew/test/support/fixtures/cask/Casks/container-7z.rb

-cask 'container-7z' do
-  version '1.2.3'
-  sha256 '3f9542ace85ed5f88549e2d0ea82210f8ddc87e0defbb78469d3aed719b3c964'
+cask "container-7z" do
+  version "1.2.3"
+  sha256 "3f9542ace85ed5f88549e2d0ea82210f8ddc87e0defbb78469d3aed719b3c964"
 
   url "file://#{TEST_FIXTURE_DIR}/cask/container.7z"
-  homepage 'https://brew.sh/container-7z'
+  homepage "https://brew.sh/container-7z"
 
-  depends_on formula: 'unar'
+  depends_on formula: "unar"
 
-  app 'container'
+  app "container"
 end