.rubocop.yml

# keep consistent (other than a few Ruby 2.0 compatible changes) with:
# https://github.com/Homebrew/brew/blob/master/Library/.rubocop_shared.yml
# and https://github.com/Homebrew/brew/blob/master/Library/.rubocop.yml

### rubocop_shared.yml
AllCops:
  # Actually supporting 2.0 for older macOS versions but RuboCop doesn't support
  # it any more so set it as old as possible.
  TargetRubyVersion: 2.3
  DisplayCopNames: false

# Disabled for 2.0 support
Layout/IndentHeredoc:
  Enabled: false

# 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:
  Blacklist:
    - 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 simple tokens without type annotations.
Style/FormatStringToken:
  EnforcedStyle: template

# This often leads to lines longer than the maximum line length.
# https://github.com/rubocop-hq/rubocop/issues/6149
Style/IfUnlessModifier:
  Enabled: false

# 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

### rubocop_shared.yml
# make our hashes consistent
Layout/AlignHash:
  EnforcedHashRocketStyle: table
  EnforcedColonStyle: table

# `system` is a special case and aligns on second argument
Layout/AlignParameters:
  Enabled: false

# favour parens-less DSL-style arguments
Lint/AmbiguousOperator:
  Enabled: false

# this is a bit less "floaty"
Layout/CaseIndentation:
  EnforcedStyle: end

# this is a bit less "floaty"
Layout/EndAlignment:
  EnforcedStyleAlignWith: start_of_line

# conflicts with DSL-style path concatenation with `/`
Layout/SpaceAroundOperators:
  Enabled: false

# Auto-correct is broken (https://github.com/rubocop-hq/rubocop/issues/6300).
Layout/EmptyLineAfterGuardClause:
  Enabled: false

# Auto-correct is broken (https://github.com/rubocop-hq/rubocop/issues/6258)
# and layout is not configurable (https://github.com/rubocop-hq/rubocop/issues/6254).
Layout/RescueEnsureAlignment:
  Enabled: false

# favour parens-less DSL-style arguments
Lint/AmbiguousBlockAssociation:
  Enabled: false

# so many of these in formulae and can't be autocorrected
# TODO: fix these as `ruby -w` complains about them.
Lint/AmbiguousRegexpLiteral:
  Enabled: false

# assignment in conditions are useful sometimes
# TODO: add parentheses for these and remove
Lint/AssignmentInCondition:
  Enabled: false

# we output how to use interpolated strings too often
Lint/InterpolationCheck:
  Enabled: false

# so many of these in formulae and can't be autocorrected
Lint/ParenthesesAsGroupedExpression:
  Enabled: false

# most metrics don't make sense to apply for formulae/taps
Metrics/AbcSize:
  Enabled: false
Metrics/ClassLength:
  Enabled: false
Metrics/CyclomaticComplexity:
  Enabled: false
Metrics/MethodLength:
  Enabled: false
Metrics/ModuleLength:
  Enabled: false
Metrics/PerceivedComplexity:
  Enabled: false

# GitHub diff UI wraps beyond 118 characters (so that's the goal)
Metrics/LineLength:
  Max: 170
  # ignore manpage comments and long single-line strings
  IgnoredPatterns: ['#: ', ' url "', ' mirror "', ' plist_options :']

# our current conditional style is established
# TODO: enable this when possible
Style/ConditionalAssignment:
  Enabled: false

# most of our APIs are internal so don't require docs
Style/Documentation:
 Enabled: false

# we want to add this slowly and manually
# TODO: add to more files
Style/FrozenStringLiteralComment:
  Enabled: false

# so many of these in formulae and can't be autocorrected
Style/GuardClause:
  Enabled: false

# depends_on a: :b looks weird in formulae.
Style/HashSyntax:
  EnforcedStyle: hash_rockets
  Exclude:
  - '**/Guardfile'
  - '**/cmd/**/*.rb'
  - '**/lib/**/*.rb'
  - '**/spec/**/*.rb'

# ruby style guide favorite
Style/StringLiterals:
  EnforcedStyle: double_quotes

# consistency with above
Style/StringLiteralsInInterpolation:
  EnforcedStyle: double_quotes

# make things a bit easier to read
Style/TernaryParentheses:
  EnforcedStyle: require_parentheses_when_complex

# messes with existing plist/caveats style
Style/TrailingBodyOnMethodDefinition:
  Enabled: false

# a bit confusing to non-Rubyists but useful for longer arrays
Style/WordArray:
  MinSize: 4