Issue 5109 - Create stylelintrc for websites and ui modules

stylelint-config-eyeo/index.js

+/*
+ * This file is part of Adblock Plus <https://adblockplus.org/>,
+ * Copyright (C) 2006-present eyeo GmbH
+ *
+ * Adblock Plus is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * Adblock Plus is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+"use strict";
+
+module.exports = {
+  extends: "stylelint-config-recommended",
+  rules: {
+    // Opening braces go on their own line
+    "block-closing-brace-empty-line-before": "never",
+    "block-closing-brace-newline-after": "always",
+    "block-closing-brace-newline-before": "always-multi-line",
+    "block-opening-brace-newline-after": "always-multi-line",
+    "block-opening-brace-newline-before": "always-multi-line",
+
+    // Use a space between the last selector and the declaration block
+    // (Google HTML/CSS Style Guide)
+    "block-closing-brace-space-after": "always-single-line",
+    "block-closing-brace-space-before": "always-single-line",
+    "block-opening-brace-space-after": "always-single-line",
+    "block-opening-brace-space-before": "always",
+
+    // Use double over single quotation marks
+    "string-quotes": "double",
+
+    // CSS color values should be specified in hexadecimal where possible
+    "color-named": "never",
+
+    // CSS shorthand properties usage is optional
+
+    // CSS rule declaration order should follow the 
+    // WordPress CSS Coding Standards
+
+    // CSS number values should specify units where possible
+
+    // Don't omit the optional leading 0 for decimal numbers
+    "number-leading-zero": "always",
+    "number-no-trailing-zeros": true,
+
+    // Two spaces per logic level (Mozilla Coding Style)
+    "indentation": 2,
+
+    // Line length should be 80 characters or less
+    "max-line-length": 80
+  }
+};