Merge pull request Expensify#145 from Expensify/Rory-AllowForOfLoops

Allow for...of loops in JS

Author: mountiny

rules/es6.js

@@ -26,5 +26,22 @@ module.exports = {
 
         // Use of `this` outside class methods can lead to crashes on minified code
         'no-invalid-this': 'error',
+
+        // Override no-restricted-syntax to allow for...of loops
+        'no-restricted-syntax': ['error',
+            {
+                selector: 'ForInStatement',
+                message: 'for..in loops iterate over the entire prototype chain, which is virtually never what you want. '
+                    + 'Use Object.{keys,values,entries}, and iterate over the resulting array.',
+            },
+            {
+                selector: 'LabeledStatement',
+                message: 'Labels are a form of GOTO; using them makes code confusing and hard to maintain and understand.',
+            },
+            {
+                selector: 'WithStatement',
+                message: '`with` is disallowed in strict mode because it makes code impossible to predict and optimize. It is also deprecated.',
+            },
+        ],
     },
 };