.scss-lint.yml

linters:

  # Documentation:
  # https://github.com/causes/scss-lint/blob/master/lib/scss_lint/linter/README.md

  # "value !important;" not "value!important ;"
  BangFormat:
    enabled: true
    space_before_bang: true
    space_after_bang: false
    severity: error

  # "border: 0" not "border: none"
  BorderZero:
    enabled: true
    severity: error
    convention: zero

  # Allow colors to be used outside of variables
  ColorVariable:
    enabled: false

  # "#00ff00" not "green"
  # (AB: Causes problems with o-colors < 3, because o-colors uses
  # color names that are also valid CSS color strings)
  ColorKeyword:
    enabled: false

  # // not /**/
  Comment:
    enabled: false

  # Disallow "@debug"
  DebugStatement:
    enabled: true
    severity: error

  # @extend must come first, then properties, then nested rulesets
  DeclarationOrder:
    enabled: true

  # Warn when the same property appears more than once in the same ruleset
  # This is not a deal breaker, as authors may repeat properties
  # in the case where both a value and its fallback are needed
  DuplicateProperty:
    enabled: true

  # "} else {" not "}\n else {"
  ElsePlacement:
    enabled: true
    style: same_line # or 'new_line'

  # Require an empty line between rulesets
  EmptyLineBetweenBlocks:
    enabled: false

  # Disallow empty rulesets
  EmptyRule:
    enabled: false

  # Require a newline at the end of the file
  FinalNewline:
    enabled: true
    present: true

  # #aabbcc good, #abc bad. Makes the codebase more searchable
  HexLength:
    enabled: true
    style: long
    severity: error

  # Require hex colors to be lowercase (if they include any of the letters a-f)
  HexNotation:
    enabled: true
    style: lowercase

  # Hex colors must be actual colors (ie not #ab or #00mm00)
  HexValidation:
    enabled: true

  # Disallow using ID Selectors
  IdSelector:
    enabled: true

  # "@import 'path/to/partial'" not "@import 'path/to/_partial.scss'"
  ImportPath:
    enabled: true
    leading_underscore: false
    filename_extension: false

  # Avoid using !important
  ImportantRule:
    enabled: true

  # Disable indentation liting since it's done via another task
  Indentation:
    enabled: false
    allow_non_nested_indentation: false

  # 0.1 not .1
  # (differs from Guardian)
  LeadingZero:
    enabled: true
    style: include_zero
    severity: error

  # Disallow more than one ruleset with the same selector in the same file
  MergeableSelector:
    enabled: false

  # Allow camelcase but forbid non-alphanumeric characters
  # in mixin, variable and function names.
  NameFormat:
    enabled: true
    convention: '^[a-z_][a-zA-Z0-9_\-]+$'
    severity: error

  # Thou shall nest 3 levels deep maximum. Not 4, nor 5.
  # See SelectorDepth for control over the actually maximum authorized depth
  NestingDepth:
    enabled: true
    max_depth: 3

  # @extend %placeholders, don't @extend .a-class
  PlaceholderInExtend:
    enabled: true
    severity: error

  # Allow any number of properties in a ruleset
  PropertyCount:
    enabled: false

  # Require properties to be in alphabetical order
  # (also possible to specify a specific order)
  # (AB: Alpha seems a bit weird. Rhys had a tool to do this,
  # maybe we should set the order here and use this tool)
  PropertySortOrder:
    enabled: false
    order: []
    separate_groups: false

  # Disallow unknown CSS property names
  PropertySpelling:
    enabled: true
    extra_properties:
      - text-size-adjust

  # ".class, [foo]" not "span.class, div[foo]"
  QualifyingElement:
    enabled: true
    allow_element_with_attribute: false
    allow_element_with_class: false
    allow_element_with_id: false
    severity: error

  # Limit selector depth
  # We decided to deal with this via peer review in
  # https://github.com/Financial-Times/ft-origami/issues/243
  SelectorDepth:
    enabled: true
    max_depth: 3

  # Allow lowercase only, but forbid non-alphanumeric characters
  # in selector names.
  SelectorFormat:
    enabled: true
    convention: '^[a-z0-9_\-]+$'
    severity: error

  # margin: 1px not margin: 1px 1px 1px 1px;
  Shorthand:
    enabled: true

  # Disallow properties on the same line "margin: 0; padding: 0;"
  SingleLinePerProperty:
    enabled: true
    # enable simple rules to be on a single line "el { margin: 0; }"
    allow_single_line_rule_sets: true
    severity: error

  # Rulesets with multiple (comma delimited) selectors
  # must have each selector on a separate line
  SingleLinePerSelector:
    enabled: true
    severity: error

  # rgb(0, 0, 0) not rgb(0,0,0)
  SpaceAfterComma:
    enabled: true
    severity: error

  # margin: 0px not margin:0px
  SpaceAfterPropertyColon:
    enabled: true
    style: one_space
    severity: error

  # margin: 0px not margin : 0px
  # (AB: clearly this should be called NoSpaceAfterPropertyName)
  SpaceAfterPropertyName:
    enabled: true
    severity: error

  # .thing { not .thing{
  SpaceBeforeBrace:
    enabled: true
    style: space
    allow_single_line_padding: false
    severity: error

  # rgb(0, 0, 0) not rgb( 0, 0, 0 )
  SpaceBetweenParens:
    enabled: true
    spaces: 0
    severity: error

  # Use single quotes, not double quotes
  # (AB: This really doesn't matter IMHO)
  # Differs from guardian
  StringQuotes:
    enabled: false

  # Every property value must end with a semicolon
  TrailingSemicolon:
    enabled: true
    severity: error

  # "margin: .5em;" not "margin: .500em;"
  TrailingZero:
    enabled: true

  # No unnecessary fractions: 1 not 1.0
  UnnecessaryMantissa:
    enabled: true
    severity: error

  # Disable this rule to allow parent references such as "& + * {}"
  UnnecessaryParentReference:
    enabled: false

  # URLs must not contain domain names
  # (AB: We may want to use build service or responsive image proxy)
  UrlFormat:
    enabled: false

  # url("example.com") not url(example.com)
  UrlQuotes:
    enabled: false

  # Allow any property to have literal values
  VariableForProperty:
    enabled: false

  # Allow vendor prefixes
  # (…by disabling the linter that forbids vendor prefixes)
  # But: ideally products should use autoprefixer or equivalent,
  # since we might eventually enable this linter.
  VendorPrefixes:
    enabled: true
    severity: warning

  # No units on zero values: 0 not 0px
  # (AB: it can be useful to express what unit you want
  # something to be in if its value is ever adjusted away from zero)
  ZeroUnit:
    enabled: false