title: How to test React component without Browserify
body: <p>I have a react application that doesn't uses the <a href="http://browserify.org/" rel="nofollow">browserify</a> tool. 
  It means that the <code>React</code> variable is exported by the script of the react js lib called in the <code>&lt;head&gt;</code>.</p>
  
  <pre><code>// React variable is already available
  var MyComponent = React.createClass({}); 
  </code></pre>
  
  <p>After implementing this component, I want to create a test for it.
  I took a look at <a href="http://facebook.github.io/jest/docs/tutorial-react.html" rel="nofollow">Jest documentation</a> and I've created my component test.</p>
  
  <pre><code>/** @jsx React.DOM */
  jest.dontMock('../compiled_jsx/components/my-component.js');
  describe('MyComponent', function() {
  it('The variables are being passed to component', function() {
    var React = require('react/addons');
  
    // In the `MyComponent` import I got the error below: 
    // ReferenceError: /compiled_jsx/components/my-component.js: React is not defined
    var myComponent = require('../compiled_jsx/components/my-component.js'); 
  });
  </code></pre>
  
  <p>In the <a href="http://facebook.github.io/jest/docs/tutorial-react.html" rel="nofollow">Jest documentation</a> example, both component and its tests uses the <code>require</code> function for getting the <code>React</code> variable.</p>
  
  <p>Is there any way to expose <code>React</code> variable into the component?
  Or it's necessary using browserify for creating this test?</p>