Use CommonJS-style requires for rewire

In order for rewire calls to be correctly handled like
require() calls by Webpack, rewire currently needs
to be imported using CommonJS style syntax.

See jhnns/rewire-webpack#12
for a discussion and explanation.

package.json

@@ -38,8 +38,8 @@
     "mocha-loader": "^0.7.1",
     "null-loader": "^0.1.1",
     "react-addons-test-utils": "^0.14.6",
-    "rewire": "^2.3.1",
-    "rewire-webpack": "^1.0.0",
+    "rewire": "^2.5.1",
+    "rewire-webpack": "^1.0.1",
     "rx": "^2.4.3",
     "webpack": "^1.7.3",
     "webpack-dev-server": "^1.7.0"

tests/TweetItem_test.js

@@ -2,12 +2,18 @@ import React from 'react';
 import {renderIntoDocument} from 'react-addons-test-utils';
 
 import {expect} from 'chai';
-import rewire from 'rewire';
 
 import setup from './setup';
 
 import TweetItem from '../src/TweetItem';
 
+// CommonJS syntax is used for importing rewire for compatibility
+// with babel-loader.
+//
+// See https://github.com/jhnns/rewire-webpack/issues/12#issuecomment-95797024
+// for an explanation
+var rewire = require('rewire');
+
 const TEST_TWEET = {
   id: 'tweet-1',
   user: {

tests/TweetList_test.js

@@ -1,13 +1,14 @@
 import React, {Component} from 'react';
 import {findDOMNode, render} from 'react-dom';
 import {createRenderer, scryRenderedComponentsWithType, renderIntoDocument} from 'react-addons-test-utils';
-import rewire from 'rewire';
 import {expect} from 'chai';
 
 import * as utils from './utils';
 
 import TweetItem from '../src/TweetItem';
 
+var rewire = require('rewire');
+
 const TEST_TWEETS = [{
   id: 'tweet-1',
   user: {