Apply rails/rails rubocop rules (except performance, md)

.rubocop.yml

@@ -0,0 +1,317 @@
+require:
+  - rubocop-minitest
+  - rubocop-packaging
+  - rubocop-rails
+
+AllCops:
+  TargetRubyVersion: 2.7
+  # RuboCop has a bunch of cops enabled by default. This setting tells RuboCop
+  # to ignore them, so only the ones explicitly set in this file are enabled.
+  DisabledByDefault: true
+  SuggestExtensions: false
+  Exclude:
+    - '**/tmp/**/*'
+    - '**/templates/**/*'
+    - '**/vendor/**/*'
+    - 'actionpack/lib/action_dispatch/journey/parser.rb'
+    - 'actionmailbox/test/dummy/**/*'
+    - 'activestorage/test/dummy/**/*'
+    - 'actiontext/test/dummy/**/*'
+    - 'tools/rail_inspector/test/fixtures/*'
+    - guides/source/debugging_rails_applications.md
+    - guides/source/active_support_instrumentation.md
+    - '**/node_modules/**/*'
+    - '**/CHANGELOG.md'
+    - '**/2_*_release_notes.md'
+    - '**/3_*_release_notes.md'
+    - '**/4_*_release_notes.md'
+    - '**/5_*_release_notes.md'
+    - '**/6_*_release_notes.md'
+
+
+# Prefer assert_not over assert !
+Rails/AssertNot:
+  Include:
+    - '**/test/**/*'
+
+# Prefer assert_not_x over refute_x
+Rails/RefuteMethods:
+  Include:
+    - '**/test/**/*'
+
+Rails/IndexBy:
+  Enabled: true
+
+Rails/IndexWith:
+  Enabled: true
+
+# Prefer &&/|| over and/or.
+Style/AndOr:
+  Enabled: true
+
+# Align `when` with `case`.
+Layout/CaseIndentation:
+  Enabled: true
+
+Layout/ClosingHeredocIndentation:
+  Enabled: true
+
+Layout/ClosingParenthesisIndentation:
+  Enabled: true
+
+# Align comments with method definitions.
+Layout/CommentIndentation:
+  Enabled: true
+
+Layout/ElseAlignment:
+  Enabled: true
+
+# Align `end` with the matching keyword or starting expression except for
+# assignments, where it should be aligned with the LHS.
+Layout/EndAlignment:
+  Enabled: true
+  EnforcedStyleAlignWith: variable
+  AutoCorrect: true
+
+Layout/EndOfLine:
+  Enabled: true
+
+Layout/EmptyLineAfterMagicComment:
+  Enabled: true
+
+Layout/EmptyLinesAroundAccessModifier:
+  Enabled: true
+  EnforcedStyle: only_before
+
+Layout/EmptyLinesAroundBlockBody:
+  Enabled: true
+
+# In a regular class definition, no empty lines around the body.
+Layout/EmptyLinesAroundClassBody:
+  Enabled: true
+
+# In a regular method definition, no empty lines around the body.
+Layout/EmptyLinesAroundMethodBody:
+  Enabled: true
+
+# In a regular module definition, no empty lines around the body.
+Layout/EmptyLinesAroundModuleBody:
+  Enabled: true
+
+# Use Ruby >= 1.9 syntax for hashes. Prefer { a: :b } over { :a => :b }.
+Style/HashSyntax:
+  Enabled: true
+
+# Method definitions after `private` or `protected` isolated calls need one
+# extra level of indentation.
+Layout/IndentationConsistency:
+  Enabled: true
+  EnforcedStyle: indented_internal_methods
+  Exclude:
+    - '**/*.md'
+
+# Two spaces, no tabs (for indentation).
+Layout/IndentationWidth:
+  Enabled: true
+
+Layout/LeadingCommentSpace:
+  Enabled: true
+
+Layout/SpaceAfterColon:
+  Enabled: true
+
+Layout/SpaceAfterComma:
+  Enabled: true
+
+Layout/SpaceAfterSemicolon:
+  Enabled: true
+
+Layout/SpaceAroundEqualsInParameterDefault:
+  Enabled: true
+
+Layout/SpaceAroundKeyword:
+  Enabled: true
+
+Layout/SpaceAroundOperators:
+  Enabled: true
+
+Layout/SpaceBeforeComma:
+  Enabled: true
+
+Layout/SpaceBeforeComment:
+  Enabled: true
+
+Layout/SpaceBeforeFirstArg:
+  Enabled: true
+
+Style/DefWithParentheses:
+  Enabled: true
+
+# Defining a method with parameters needs parentheses.
+Style/MethodDefParentheses:
+  Enabled: true
+
+Style/ExplicitBlockArgument:
+  Enabled: true
+
+Style/FrozenStringLiteralComment:
+  Enabled: true
+  EnforcedStyle: always
+  Exclude:
+    - 'actionview/test/**/*.builder'
+    - 'actionview/test/**/*.ruby'
+    - 'actionpack/test/**/*.builder'
+    - 'actionpack/test/**/*.ruby'
+    - 'activestorage/db/migrate/**/*.rb'
+    - 'activestorage/db/update_migrate/**/*.rb'
+    - 'actionmailbox/db/migrate/**/*.rb'
+    - 'actiontext/db/migrate/**/*.rb'
+    - '**/*.md'
+
+Style/MapToHash:
+  Enabled: true
+
+Style/RedundantFreeze:
+  Enabled: true
+
+# Use `foo {}` not `foo{}`.
+Layout/SpaceBeforeBlockBraces:
+  Enabled: true
+
+# Use `foo { bar }` not `foo {bar}`.
+Layout/SpaceInsideBlockBraces:
+  Enabled: true
+  EnforcedStyleForEmptyBraces: space
+
+# Use `{ a: 1 }` not `{a:1}`.
+Layout/SpaceInsideHashLiteralBraces:
+  Enabled: true
+
+Layout/SpaceInsideParens:
+  Enabled: true
+
+# Check quotes usage according to lint rule below.
+Style/StringLiterals:
+  Enabled: true
+  EnforcedStyle: double_quotes
+
+# Detect hard tabs, no hard tabs.
+Layout/IndentationStyle:
+  Enabled: true
+
+# Empty lines should not have any spaces.
+Layout/TrailingEmptyLines:
+  Enabled: true
+
+# No trailing whitespace.
+Layout/TrailingWhitespace:
+  Enabled: true
+
+# Use quotes for string literals when they are enough.
+Style/RedundantPercentQ:
+  Enabled: true
+
+Lint/AmbiguousOperator:
+  Enabled: true
+
+Lint/AmbiguousRegexpLiteral:
+  Enabled: true
+
+Lint/DuplicateRequire:
+  Enabled: true
+
+Lint/DuplicateMagicComment:
+  Enabled: true
+
+Lint/DuplicateMethods:
+  Enabled: true
+
+Lint/ErbNewArguments:
+  Enabled: true
+
+Lint/EnsureReturn:
+  Enabled: true
+
+# Use my_method(my_arg) not my_method( my_arg ) or my_method my_arg.
+Lint/RequireParentheses:
+  Enabled: true
+
+Lint/RedundantStringCoercion:
+  Enabled: true
+
+Lint/RedundantSafeNavigation:
+  Enabled: true
+
+Lint/UriEscapeUnescape:
+  Enabled: true
+
+Lint/UselessAssignment:
+  Enabled: true
+
+Lint/DeprecatedClassMethods:
+  Enabled: true
+
+Lint/InterpolationCheck:
+  Enabled: true
+  Exclude:
+    - '**/test/**/*'
+
+Style/EvalWithLocation:
+  Enabled: true
+  Exclude:
+    - '**/test/**/*'
+
+Style/ParenthesesAroundCondition:
+  Enabled: true
+
+Style/HashTransformKeys:
+  Enabled: true
+
+Style/HashTransformValues:
+  Enabled: true
+
+Style/RedundantBegin:
+  Enabled: true
+
+Style/RedundantReturn:
+  Enabled: true
+  AllowMultipleReturnValues: true
+
+Style/RedundantRegexpEscape:
+  Enabled: true
+
+Style/Semicolon:
+  Enabled: true
+  AllowAsExpressionSeparator: true
+
+# Prefer Foo.method over Foo::method
+Style/ColonMethodCall:
+  Enabled: true
+
+Style/TrivialAccessors:
+  Enabled: true
+
+# Prefer a = b || c over a = b ? b : c
+Style/RedundantCondition:
+  Enabled: true
+
+Style/RedundantDoubleSplatHashBraces:
+  Enabled: true
+
+Minitest/AssertPredicate:
+  Enabled: true
+
+Minitest/AssertRaisesWithRegexpArgument:
+  Enabled: true
+
+Minitest/AssertWithExpectedArgument:
+  Enabled: true
+
+Minitest/LiteralAsActualArgument:
+  Enabled: true
+
+Minitest/SkipEnsure:
+  Enabled: true
+
+Minitest/UnreachableAssertion:
+  Enabled: true

Gemfile

@@ -1,8 +1,14 @@
+# frozen_string_literal: true
+
 source "https://rubygems.org"
 
 gem "buildkit"
 gem "buildkite-builder"
 gem "diffy"
 gem "rake"
 gem "debug"
-gem "activesupport"
+gem "activesupport"
+gem "rubocop"
+gem "rubocop-minitest"
+gem "rubocop-packaging"
+gem "rubocop-rails"