Issue 3692 - Add base ESLint configuration

eslint-config-eyeo/index.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2017 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/>.
  */
 
 /* eslint-env commonjs */
-/* eslint quote-props: ["error", "always"] */
 
 "use strict";
 
 module.exports = {
-  "extends": "eslint:recommended",
-  "env": {
-    "es6": true
+  extends: "eslint:recommended",
+  env: {
+    es6: true
   },
-  "rules": {
+  rules: {
     "array-bracket-spacing": "error",
     "arrow-spacing": "error",
     "block-scoped-var": "error",
     "block-spacing": "error",
-    "brace-style": ["error", "allman", {"allowSingleLine": true}],
-    "camelcase": ["error", {"properties": "never"}],
+    "brace-style": ["error", "allman", {allowSingleLine: true}],
+    "camelcase": ["error", {properties: "never"}],
     "comma-dangle": "error",
     "comma-spacing": "error",
     "comma-style": "error",
     "computed-property-spacing": "error",
-    "curly": ["error", "multi-or-nest", "consistent"],
+    "curly": ["error", "multi-or-nest"],
     "eol-last": "error",
     "func-call-spacing": "error",
-    "indent": ["error", 2, {"SwitchCase": 1, "ArrayExpression": "first"}],
+    "indent": ["error", 2, {SwitchCase: 1, ArrayExpression: "first"}],
     "key-spacing": "error",
     "keyword-spacing": "error",
     "linebreak-style": "error",
     "lines-around-directive": "error",
-    "max-len": ["error", 80, {"ignoreUrls": true}],
+    "max-len": ["error", 80, {ignoreUrls: true}],
     "new-parens": "error",
     "no-array-constructor": "error",
     "no-caller": "error",
     "no-case-declarations": "off",
     "no-catch-shadow": "error",
     "no-cond-assign": "off",
-    "no-console": ["error", {"allow": ["warn", "error", "trace"]}],
+    "no-console": ["error", {allow: ["warn", "error", "trace"]}],
     "no-control-regex": "off",
     "no-else-return": "error",
+    "no-empty": ["error", {allowEmptyCatch: true}],
     "no-eval": "error",
     "no-extra-bind": "error",
     "no-extra-label": "error",
     "no-implied-eval": "error",
-    "no-labels": "error",

[Sebastian Noack, 2017/02/12 20:53:12]

I posted this rule by accident among the other rules I suggested to add. You
have to label outer loops in order to break out of it from an inner loop. While
we currently have no need for this (in adblockpluschrome), I think this is a
legit use case. The alternative is much more complex. And in fact we currently
have a patch under review where we have to break out of an outer loop.

[kzar, 2017/02/13 06:02:58]

Good point. How about we leave this rule enabled but with the allowLoop option?

[Sebastian Noack, 2017/02/13 11:31:29]

Yeah, at very least we should add the "allowLoop" option. But we might just
remove this rule altogether, if it is just to avoid unnecessary complexity in
the ESLint configuration. Labeling random blocks isn't quite a common practice,
and inappropriate use of labels is unlikely to make it past our code review or
to create controversy during the review. No strong opinion though.

[kzar, 2017/02/13 13:02:21]

I've never seen a use-case for labels which didn't involve breaking out of
nested loops, so I think it's OK to leave the rule on with that option.

[Sebastian Noack, 2017/02/13 14:20:28]

The same way, you could argue, because it is so rare, it's not worth even having
that rule. Or you could even go one step further, and argue because there are no
representative examples of either good or bad usage, protecting against labels
with a rule would be premature. ;) But I suppose it doesn't matter much.

+    "no-labels": ["error", {allowLoop: true}],
     "no-lone-blocks": "error",
     "no-lonely-if": "error",
     "no-multi-spaces": "error",
     "no-new-func": "error",
     "no-new-object": "error",
     "no-proto": "error",
     "no-self-compare": "error",
     "no-shadow": "error",
     "no-trailing-spaces": "error",
     "no-unneeded-ternary": "error",
     "no-unused-vars": "off",
     "no-useless-computed-key": "error",
     "no-useless-concat": "error",
     "no-useless-escape": "error",
     "no-useless-return": "error",
     "no-var": "error",
     "no-warning-comments": "error",
     "no-whitespace-before-property": "error",
     "no-with": "error",
     "object-curly-spacing": "error",
     "object-shorthand": ["error", "always", {
-      "avoidExplicitReturnArrows": true
+      avoidExplicitReturnArrows: true
     }],
     "one-var": ["error", "never"],
     "operator-assignment": "error",
     "operator-linebreak": "error",
     "padded-blocks": ["error", "never"],
     "prefer-arrow-callback": "error",
-    "prefer-destructuring": ["error", {"array": false}],
+    "prefer-destructuring": ["error", {array: false}],
     "prefer-numeric-literals": "error",
     "prefer-rest-params": "error",
     "prefer-spread": "error",
-    "quote-props": ["error", "as-needed"],
-    "quotes": ["error", "double", {"avoidEscape": true}],
+    "quote-props": ["error", "consistent-as-needed"],
+    "quotes": ["error", "double", {avoidEscape: true}],
     "radix": "error",
     "rest-spread-spacing": "error",
     "semi": "error",
     "semi-spacing": "error",
     "space-before-function-paren": ["error", "never"],
     "space-in-parens": "error",
     "space-infix-ops": "error",
     "space-unary-ops": "error",
     "spaced-comment": "error",
     "strict": ["error", "global"],
     "valid-jsdoc": ["error", {
-      "requireParamDescription": false,
-      "requireReturn": false,
-      "requireReturnDescription": false
+      requireParamDescription: false,
+      requireReturn: false,
+      requireReturnDescription: false
     }],
     "yield-star-spacing": "error",
     "yoda": "error"
   }
 };