Add SCSS Lint, CSSComb config file, run SCSS Lint in GitLab CI, add documentation for SCSS Style Guide.

See !3069 for more information.

1 files changed, 158 insertions, 0 deletions

diff --git a/.scss-lint.yml b/.scss-lint.yml
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index 00000000000..e350b2073c3
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+++ b/.scss-lint.yml
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+# Linter Documentation:
+# https://github.com/brigade/scss-lint/blob/master/lib/scss_lint/linter/README.md
+
+scss_files: 'app/assets/stylesheets/**/*.scss'
+
+exclude:
+  - 'app/assets/stylesheets/pages/emojis.scss'
+
+linters:
+  BangFormat:
+    enabled: false
+  
+  BorderZero:
+    enabled: false
+  
+  ColorKeyword:
+    enabled: false
+  
+  ColorVariable:
+    enabled: false
+  
+  Comment:
+    enabled: false
+  
+  DeclarationOrder:
+    enabled: false
+
+  # `scss-lint:disable` control comments should be preceded by a comment
+  # explaining why these linters are being disabled for this file.
+  # See https://github.com/brigade/scss-lint#disabling-linters-via-source for
+  # more information.
+  DisableLinterReason:
+    enabled: true
+  
+  DuplicateProperty:
+    enabled: false
+  
+  EmptyLineBetweenBlocks:
+    enabled: false
+  
+  EmptyRule:
+    enabled: false
+  
+  FinalNewline:
+    enabled: false
+  
+  # HEX colors should use three-character values where possible.
+  HexLength:
+    enabled: true
+  
+  # HEX color values should use lower-case colors to differentiate between
+  # letters and numbers, e.g. `#E3E3E3` vs. `#e3e3e3`.
+  HexNotation:
+    enabled: true
+  
+  IdSelector:
+    enabled: false
+  
+  ImportPath:
+    enabled: false
+  
+  ImportantRule:
+    enabled: false
+  
+  # Indentation should always be done in increments of 2 spaces.
+  Indentation:
+    enabled: true
+    width: 2
+  
+  LeadingZero:
+    enabled: false
+  
+  MergeableSelector:
+    enabled: false
+  
+  NameFormat:
+    enabled: false
+  
+  NestingDepth:
+    enabled: false
+
+  PlaceholderInExtend:
+    enabled: false
+
+  PropertySortOrder:
+    enabled: false
+  
+  PropertySpelling:
+    enabled: false
+  
+  PseudoElement:
+    enabled: false
+  
+  QualifyingElement:
+    enabled: false
+  
+  SelectorDepth:
+    enabled: false
+  
+  # Selectors should always use hyphenated-lowercase, rather than camelCase or
+  # snake_case.
+  SelectorFormat:
+    enabled: true
+    convention: hyphenated_lowercase
+  
+  # Prefer the shortest shorthand form possible for properties that support it.
+  Shorthand:
+    enabled: true
+  
+  # Each property should have its own line, except in the special case of
+  # single line rulesets.
+  SingleLinePerProperty:
+    enabled: true
+    allow_single_line_rule_sets: true
+
+  SingleLinePerSelector:
+    enabled: false
+  
+  SpaceAfterComma:
+    enabled: false
+  
+  # Properties should be formatted with a single space separating the colon
+  # from the property's value.
+  SpaceAfterPropertyColon:
+    enabled: true
+
+  # Properties should be formatted with no space between the name and the
+  # colon.
+  SpaceAfterPropertyName:
+    enabled: true
+  
+  SpaceAroundOperator:
+    enabled: false
+  
+  SpaceBeforeBrace:
+    enabled: false
+  
+  StringQuotes:
+    enabled: false
+
+  TrailingSemicolon:
+    enabled: false
+
+  TrailingWhitespace:
+    enabled: false
+
+  UnnecessaryMantissa:
+    enabled: false
+
+  UnnecessaryParentReference:
+    enabled: false
+
+  VendorPrefix:
+    enabled: false
+
+  # Omit length units on zero values, e.g. `0px` vs. `0`.
+  ZeroUnit:
+    enabled: true