Replace gulp with plain npm for linting.

.eslintrc.yaml

@@ -1,7 +1,11 @@
-extends: eslint:recommended
 env:
-  browser: true,
+  browser: true
-  es6: true
+  es2021: true
+extends: 'eslint:recommended'
+plugins:
+  - template
+parserOptions:
+  ecmaVersion: 12
 globals:
   jQuery: true
   u: true
@@ -17,7 +21,6 @@ rules:
   comma-dangle:
     - "error"
     - never
-  comma-spacing: "error"
   comma-style:
     - "error"
     - last

.sass-lint.yml

@@ -1,124 +0,0 @@
-# Documentation for the sass-lint Linters is available at:
-# https://github.com/sasstools/sass-lint/tree/master/docs/rules
-
-options:
-  formatter: stylish
-  merge-default-rules: true
-rules:
-  # Extends
-  extends-before-mixins: 2
-  extends-before-declarations: 2
-  placeholder-in-extend: 2
-
-  # Mixins
-  mixins-before-declarations:
-    - 2
-    - exclude:
-      - 'breakpoint'
-      - 'mq'
-      - 'respond-to'
-      - 'rtl'
-      - 'zen-breakpoint'
-      - 'zen-layout'
-      - 'zen-mq'
-      - 'zen-respond-to'
-
-  # Line Spacing
-  one-declaration-per-line: 2
-  empty-line-between-blocks:
-    - 2
-    - ignore-single-line-rulesets: false
-  single-line-per-selector: 2
-
-  # Disallows
-  no-attribute-selectors: 0
-  no-color-hex: 2
-  no-color-keywords: 2
-  no-color-literals: 2
-  no-combinators: 0
-  no-css-comments: 2
-  no-debug: 2
-  no-disallowed-properties: 2
-  no-duplicate-properties: 2
-  no-empty-rulesets: 0
-  no-extends: 0
-  no-ids: 2
-  no-important: 2
-  no-invalid-hex: 2
-  no-mergeable-selectors: 2
-  no-misspelled-properties:
-    - 2
-    - extra-properties:
-      - '*font-family'
-      - '*height'
-      - 'interpolation-mode'
-      - '*margin-left'
-      - '*vertical-align'
-      - '*width'
-  no-qualifying-elements: 0
-  no-trailing-whitespace: 2
-  no-trailing-zero: 2
-  no-transition-all: 0
-  no-universal-selectors: 0
-  no-url-protocols: 2
-  no-vendor-prefixes: 2
-  no-warn: 2
-  property-units: 0
-
-  # Nesting
-  force-attribute-nesting: 0
-  force-element-nesting: 0
-  force-pseudo-nesting: 0
-
-  # Name Formats
-  class-name-format:
-    - 2
-    - convention: hyphenatedbem
-  function-name-format: 2
-  id-name-format: 2
-  mixin-name-format:
-    - 2
-    - convention: hyphenatedbem
-  placeholder-name-format:
-    - 2
-    - convention: hyphenatedbem
-  variable-name-format: 2
-
-  # Style Guide
-  attribute-quotes: 2
-  bem-depth: 0
-  border-zero: 2
-  brace-style:
-    - 2
-    - style: stroustrup
-    - allow-single-line: false
-  clean-import-paths: 2
-  empty-args: 0
-  hex-length: 2
-  hex-notation: 2
-  indentation: 2
-  leading-zero: 2
-  nesting-depth:
-    - 2
-    - max-depth: 4
-  property-sort-order: 0
-  pseudo-element: 1
-  quotes: 2
-  shorthand-values: 2
-  url-quotes: 2
-  variable-for-property: 2
-  zero-unit: 2
-
-  # Inner Spacing
-  space-after-comma: 2
-  space-before-colon: 2
-  space-after-colon: 2
-  space-before-brace: 2
-  space-before-bang: 2
-  space-after-bang: 2
-  space-between-parens: 0
-  space-around-operator: 0
-
-  # Final Items
-  trailing-semicolon: 2
-  final-newline: 2

.stylelintrc.yaml

@@ -0,0 +1,84 @@
+plugins:
+  - stylelint-scss
+rules:
+  at-rule-disallowed-list:
+    - debug
+  at-rule-no-unknown:
+  at-rule-no-vendor-prefix: true
+  block-no-empty: true
+  block-opening-brace-space-before: always
+  color-hex-case: lower
+  color-hex-length: short
+  color-named: never
+  color-no-hex: true
+  color-no-invalid-hex: true
+  declaration-bang-space-after: never
+  declaration-bang-space-before: always
+  declaration-block-semicolon-newline-after: always
+  declaration-block-semicolon-space-before: never
+  declaration-block-single-line-max-declarations: 1
+  declaration-block-trailing-semicolon: always
+  declaration-colon-space-after: always-single-line
+  declaration-colon-space-before: never
+  declaration-no-important: true
+  declaration-property-value-disallowed-list:
+    border:
+      - none
+    border-top:
+      - none
+    border-right:
+      - none
+    border-bottom:
+      - none
+    border-left:
+      - none
+  function-comma-space-after: always-single-line
+  function-parentheses-space-inside: never
+  function-url-quotes: always
+  indentation: 2
+  length-zero-no-unit: true
+  max-nesting-depth:
+    - 3
+    - ignoreAtRules:
+      - each
+      - media
+      - supports
+      - include
+  media-feature-name-no-vendor-prefix: true
+  media-feature-parentheses-space-inside: never
+  no-missing-end-of-source-newline: true
+  number-leading-zero: never
+  number-no-trailing-zeros: true
+  property-no-unknown: true
+  property-no-vendor-prefix: true
+  rule-empty-line-before:
+    - always-multi-line
+    - except:
+      - first-nested
+      ignore:
+      - after-comment
+  scss/at-extend-no-missing-placeholder: true
+  scss/at-function-pattern: "^[a-z]+([a-z0-9-]+[a-z0-9]+)?$"
+  scss/at-import-no-partial-leading-underscore: true
+  scss/at-import-partial-extension-blacklist:
+  - scss
+  scss/at-mixin-pattern: "^[a-z]+([a-z0-9-]+[a-z0-9]+)?$"
+  scss/at-rule-no-unknown: true
+  #scss/dollar-variable-colon-space-after: always
+  scss/dollar-variable-colon-space-before: never
+  scss/dollar-variable-pattern: "^[_]?[a-z]+([a-z0-9-]+[a-z0-9]+)?$"
+  #scss/percent-placeholder-pattern: "^[a-z]+([a-z0-9-]+[a-z0-9]+)?$"
+  #scss/selector-no-redundant-nesting-selector: true
+  selector-class-pattern:
+    - "^[a-z0-9\\-]+$"
+    - message: Selector should be written in lowercase with hyphens (selector-class-pattern)
+  selector-list-comma-newline-after: always
+  selector-max-compound-selectors: 3
+  selector-max-id: 0
+  #selector-no-qualifying-type: true
+  selector-no-vendor-prefix: true
+  selector-pseudo-element-colon-notation: double
+  selector-pseudo-element-no-unknown: true
+  shorthand-property-no-redundant-values: true
+  string-quotes: single
+  value-no-vendor-prefix: true

assets/js/cookieconsent.js

@@ -1,3 +1,4 @@
+/* eslint-disable no-undef */
 (function () {
 
   'use strict';

assets/js/script.js

@@ -3,10 +3,10 @@
  * A JavaScript file for the theme.
  */
 
-(function ($) {
+(function () {
 
   'use strict';
 
   // Place your code here.
 
-})(u);
+})();

assets/js/search.js

@@ -1,3 +1,5 @@
+/* eslint-disable no-undef */
+
 /**
  * @file
  * A JavaScript file for flexsearch.
@@ -36,7 +38,7 @@
     results.appendChild(fragment);
   }
 
-  function doSearch () {
+  function doSearch() {
     const query = document.querySelector('.search-text').value.trim();
     const results = flexSearch.search({
       query: query,
@@ -45,21 +47,21 @@
     showResults(results);
   }
 
-  function enableUI () {
+  function enableUI() {
     const searchform = document.querySelector('.search-form');
     searchform.addEventListener('submit', function (e) {
       e.preventDefault();
       doSearch();
-    })
+    });
     searchform.addEventListener('keyup', function () {
       doSearch();
-    })
+    });
     document.querySelector('.search-loading').classList.add('hidden');
     document.querySelector('.search-input').classList.remove('hidden');
     document.querySelector('.search-text').focus();
   }
 
-  function buildIndex () {
+  function buildIndex() {
     document.querySelector('.search-loading').classList.remove('hidden');
     fetch('/searchindex.json')
       .then(function (response) {

assets/js/tracking.js

@@ -1,3 +1,5 @@
+/* eslint-disable no-undef */
+
 /**
  * @file
  * A JavaScript file for analytic tracking.

assets/sass/_custom.scss

@@ -1,3 +1,3 @@
-// sass-lint:disable no-css-comments, no-color-hex, no-color-literals
+// stylelint-disable color-no-hex, color-named
 
 // Site custom styles

assets/sass/_zen.scss

@@ -83,7 +83,6 @@ aside {
 }
 
 article {
-
   & > header {
     color: $text-meta;
   }

assets/sass/base/document/_document.scss

@@ -1,4 +1,4 @@
-// sass-lint:disable no-vendor-prefixes
+// stylelint-disable property-no-vendor-prefix
 
 // Document
 //

assets/sass/base/forms/_forms.scss

@@ -1,4 +1,4 @@
-// sass-lint:disable no-vendor-prefixes, no-css-comments
+// stylelint-disable property-no-vendor-prefix
 
 // Form defaults
 //

assets/sass/base/links/_links.scss

@@ -14,7 +14,7 @@
 a,
 %link {
   color: $link;
-  // sass-lint:disable no-vendor-prefixes
+  // stylelint-disable property-no-vendor-prefix
   // Remove gaps in links underline in iOS 8+ and Safari 8+.
   -webkit-text-decoration-skip: objects;
 }

assets/sass/base/text/_text.scss

@@ -10,7 +10,7 @@
 abbr[title] {
   // Remove the bottom border in Chrome 57- and Firefox 39-.
   border-bottom: 0;
-  // sass-lint:disable no-duplicate-properties
+  // stylelint-disable no-duplicate-properties
   // Add the correct text decoration in Chrome, Edge, IE, Opera, and Safari.
   text-decoration: underline;
   text-decoration: underline dotted;
@@ -31,7 +31,7 @@ strong {
   font-weight: inherit;
 }
 
-// sass-lint:disable no-mergeable-selectors
+// stylelint-disable no-mergeable-selectors
 b,
 strong {
   // Add the correct font weight in Chrome, Edge, and Safari.

assets/sass/components/button/_button.scss

@@ -14,7 +14,7 @@ button,
 [type='button'],
 [type='reset'],
 [type='submit'] {
-  // sass-lint:disable no-color-hex, no-color-literals
+  // stylelint-disable color-no-hex, color-named
   @extend %button--disabled;
   @include typeface(headings);
   @include margin-right(.75);
@@ -38,7 +38,7 @@ button,
   border-bottom-color: #b4b4b4;
   border-radius: 2px;
 
-  // sass-lint:disable no-vendor-prefixes
+  // stylelint-disable property-no-vendor-prefix
   // Correct the inability to style clickable types in iOS and Safari.
   -moz-appearance: button;
   -webkit-appearance: button;
@@ -53,7 +53,7 @@ button,
   &:-moz-focusring {
     outline: 1px dotted ButtonText;
   }
-  // sass-lint:enable no-vendor-prefixes
+  // sass-lint:enable property-no-vendor-prefix
 
   &:hover,
   &:focus,

assets/sass/components/cookieconsent/_cookieconsent.scss

@@ -3,11 +3,11 @@
 .cookieconsent {
   @include type-layout(s, 1);
   position: sticky;
-  bottom:  0;
+  bottom: 0;
   width: 100%;
   color: $warning;
   background-color: $warning-bg;
-  border-top:  4px solid $warning-border;
+  border-top: 4px solid $warning-border;
   text-align: center;
   transform: translateY(100vh);
   transition: all 130ms ease-in;

assets/sass/components/inline-sibling/_inline-sibling.scss

@@ -1,3 +1,5 @@
+// stylelint-disable selector-max-compound-selectors
+
 // Inline sibling
 //
 // An element that needs to appear inline with the content that follows.

assets/sass/components/watermark/_watermark.scss

@@ -14,7 +14,7 @@
   font-size: 75px;
   line-height: 1;
   text-align: center;
-  // sass-lint:disable no-color-literals
+  // stylelint-disable no-color-literals
   text-shadow: 0 0 1px rgba(0, 0, 0, .1);
   word-wrap: break-word;
 }

assets/sass/components/wireframe/_wireframe.scss

@@ -9,7 +9,6 @@ $with-wireframes: false !default;
 // variable: `$with-wireframes: true;`
 
 @if $with-wireframes {
-
   .wireframe,
   %wireframe {
     outline: 1px solid $border;
@@ -31,5 +30,4 @@ $with-wireframes: false !default;
       @extend %wireframe;
     }
   }
-
 }

assets/sass/init/_colors.scss

@@ -1,4 +1,4 @@
-// sass-lint:disable no-color-keywords; no-color-hex
+// stylelint-disable color-no-hex, color-named
 
 // Base colors.
 $black:                  #000;

assets/sass/init/_variables.scss

@@ -102,7 +102,7 @@ $typefaces: (
     // We could also specify the following property:
     // letter-spacing: .5px,
   ),
-);
+); // stylelint-disable indentation
 
 // Output a horizontal grid to help with debugging typography.
 $typey-debug: false;