Merge pull request #2743 "Add ESLint".

- Adds ESLint checking to the automated tests, using most of the
  eslint:recommended rules in addition to some style rules.
- Adds two "local" ESLint rules to match MooTools' specific whitespace
  and indentation styles, in Grunt/plugins/eslint/rules.
- Fixes syntax inconsistencies based on ESLint results.

Author: timwienk

.eslintrc

@@ -0,0 +1,20 @@
+root: true
+
+extends: 'eslint:recommended'
+
+rules:
+  no-cond-assign: 0
+  no-constant-condition: 0
+  no-empty: 0
+  no-extra-semi: 0
+  no-octal: 0
+  no-undef: 0
+  no-unused-vars: 0
+  linebreak-style: [2, unix]
+  no-trailing-spaces: 2
+  no-unneeded-ternary: 2
+  quotes: [2, single, avoid-escape]
+  semi: 2
+  semi-spacing: 2
+  mootools-indent: [2, tab, {SwitchCase: 1, VariableDeclarator: 1, IndentRootIIFE: false}]
+  mootools-whitespace: 2

Grunt/options/build.js

@@ -69,6 +69,17 @@ module.exports = function(grunt){
 				src: build.server.sources,
 				dest: dir.build + '/mootools-core.js'
 			}
+		},
+		eslint: {
+			'compat': {
+				src: ['Gruntfile.js', 'Grunt/{options,tasks}/*.js', build.compat.sources, build.compat.specs]
+			},
+			'nocompat': {
+				src: ['Gruntfile.js', 'Grunt/{options,tasks}/*.js', build.nocompat.sources, build.nocompat.specs]
+			},
+			'server': {
+				src: ['Gruntfile.js', 'Grunt/{options,tasks}/*.js', build.server.sources, build.server.specs]
+			}
 		}
 	};
 

Grunt/options/options.js

@@ -4,9 +4,7 @@ var path = require('path');
 var browsers = require('./browsers');
 
 module.exports = function(grunt){
-	var dir = grunt.config.get('environment.dir'),
-		build = grunt.config.get('environment.build'),
-		travis = grunt.config.get('environment.travis'),
+	var travis = grunt.config.get('environment.travis'),
 		sauceLabs = grunt.config.get('environment.sauceLabs');
 
 	var config = {
@@ -46,6 +44,11 @@ module.exports = function(grunt){
 				compress: true,
 				preserveComments: 'some'
 			}
+		},
+		eslint: {
+			options: {
+				rulePaths: ['Grunt/plugins/eslint/rules']
+			}
 		}
 	};