Add gulp task for JavaScript files linting

src/.eslintrc

@@ -0,0 +1,26 @@
+{
+    "extends": "eslint:recommended",
+    "rules": {
+        "indent": ["error", 4, {"SwitchCase": 1}],
+        "no-trailing-spaces": "error",
+        "semi": ["error", "always"],
+        "guard-for-in": "error"
+    },
+    "globals": {
+        "Mibew": true,
+        "MibewAPI": true,
+        "MibewAPIInteraction": true,
+        "MibewAPIChatInteraction": true,
+        "MibewAPIUsersInteraction": true,
+        "MibewAPIExecutionContext": true,
+        "Handlebars": true,
+        "_": true,
+        "Backbone": true,
+        "jQuery": true,
+        "vex": true,
+        "validator": true
+    },
+    "env":{
+        "browser": true
+    }
+}

src/gulpfile.js

@@ -24,7 +24,8 @@ var fs = require('fs'),
     chmod = require('gulp-chmod'),
     xgettext = require('gulp-xgettext'),
     concatPo = require('gulp-concat-po'),
-    rename = require('gulp-rename');
+    rename = require('gulp-rename'),
+    eslint = require('gulp-eslint');
 
 // Set global configs.
 var config = {
@@ -83,6 +84,14 @@ gulp.task('phpcs', ['composer-install-dev'], function() {
     .pipe(phpcs.reporter('fail'));
 });
 
+// Checks all JavaScript Source files with ESLint.
+gulp.task('eslint', function() {
+    return gulp.src(config.jsPath + '/source/**/*.js')
+        .pipe(eslint())
+        .pipe(eslint.format())
+        .pipe(eslint.failAfterError());
+});
+
 // Get and install PHP Composer
 gulp.task('get-composer', function(callback) {
     // Check if Composer already in place

src/package.json

@@ -23,6 +23,8 @@
         "lodash": "~3.9.3",
         "strftime": "~0.9.2",
         "del": "~1.2.0",
-        "event-stream": "~3.3.1"
+        "event-stream": "~3.3.1",
+        "eslint": "~2.11.0",
+        "gulp-eslint": "~2.0.0"
     }
 }