Merge pull request #116 from mobify/modern-eslint-es5-compatibility

Modern eslint ES5 compatibility

Author: Daniel Brook-Roberge

CHANGELOG

@@ -1,3 +1,5 @@
+2.5.2
+    - Add a new ES5 configuration ported to ESLint 2 and up
 2.5.1
     - Update line length to 200
     - Remove 'strict' rule for modules

README.md

@@ -4,17 +4,29 @@ A repo to document code standards for different languages and provide tools for
 
 [![NPM version](https://badge.fury.io/js/mobify-code-style.svg)](http://badge.fury.io/js/mobify-code-style)
 
-## JavaScript (ES5)
+## JavaScript (ES5) with Grunt
 
-Typically, we lint our javascript files using [Grunt](http://gruntjs.com/) and [grunt-eslint](https://github.com/sindresorhus/grunt-eslint). grunt-eslint is a Grunt helper for the [ESLint](http://eslint.org/) linter.
+Typically, we lint our javascript files using
+[Grunt](http://gruntjs.com/) and
+[grunt-eslint](https://github.com/sindresorhus/grunt-eslint). grunt-eslint
+is a Grunt helper for the [ESLint](http://eslint.org/) linter.
 
 To add javascript linting to your project:
 
  1. Install the NPM `mobify-code-style` and `grunt-eslint` modules.
- 2. Create a [Gruntfile](http://gruntjs.com/sample-gruntfile) if you don't have one already.
- 3. In the initConfig of your gruntfile, add a section for eslint pointing to the correct linting file.
+ 2. Create a [Gruntfile](http://gruntjs.com/sample-gruntfile) if you
+    don't have one already.
+ 3. Create an `.eslintrc.yml` file in the root of your project directory
+ 4. In the initConfig of your gruntfile, add a section for eslint pointing to the correct linting file.
 
-Sample eslint config:
+The `.eslintrc.yml` file should contain, to begin with:
+```yaml
+extends:
+  - './node_modules/mobify-code-style/es5/mobify-es5.yml'
+```
+
+
+Sample eslint Grunt config:
 
 ```javascript
 eslint:{
@@ -24,20 +36,36 @@ eslint:{
             // When true, eslint will test _only_ the rules set in the provided
             // configuration file
             reset: false,
-            config: 'node_modules/mobify-code-style/javascript/.eslintrc'
+            configFile: './.eslintrc.yml'
         }
     }
 }
 ```
 
+### Migrating from ESLint 0.x or 1.x to ESlint 2.x or 3.x
+
+If you upgrade the version of `grunt-eslint` you use from one that
+pulls in ESLint 1.x or lower to one that pulls
+in ESLint 2.x or greater, you must modify the configuration files to
+include the new style of configuration.
+
+If the Grunt config includes the default config
+`./node_modules/mobify-code-style/javascript/.eslintrc`, replace that
+with `./.eslintrc.yml`, and add an `.eslintrc.yml` to the project root
+as described above.
+
+If there are modifications to the lint configuration in the project,
+please check the migration guides at [http://eslint.org/] to port the
+modified lint config to ESLint 3.x.
+
 ## ES6/JSX
 
 We use [ESLint](http://eslint.org/) to lint ES6 and React/JSX code. If ESLint is installed in a project, we can use the configuration from this module by creating a file in the project root named `.eslintrc.yml`. If the project does not use JSX, the file contents should be
 
 ```yaml
 extends:
   - './node_modules/mobify-code-style/es6/mobify-es6.yml'
-```  
+```
 
 and for a React/JSX project: