The code

``` javascript
class Comp extends React.Component {
  componentWillMount() {
    setTimeout(() => {
      this.setState({});
    });
  }

  render() {
    return <div onClick={() => {}} />;
  }
}

ReactDOMServer.renderToString(<Comp />);
```

produces errors:

> Warning: React can't find the root component node for data-reactid value `.0`. If you're seeing this message, it probably means that you've loaded two copies of React on the page. At this time, only a single copy of React can be loaded at a time.
> 
> Uncaught TypeError: Cannot read property 'firstChild' of undefined

But if I remove `onClick` handler the errors go away...

See demo: http://codepen.io/dened/pen/YyByYr

render: function() {
          return <span><NestedComponent /></span>;
        },
      });
      var response = ReactServerRendering.renderToStaticMarkup(
        <TestComponent />
      );
      expect(response).toBe('<span><div>inner text</div></span>');
    });
    it('should not put checksum and React ID on text components', function() {
      var TestComponent = React.createClass({
        render: function() {
          return <span>{'hello'} {'world'}</span>;
        },
      });
      var response = ReactServerRendering.renderToStaticMarkup(
        <TestComponent />
      );
      expect(response).toBe('<span>hello world</span>');
    });
    it('should not register event listeners', function() {
      var EventPluginHub = require('EventPluginHub');
      var cb = jest.fn();
      ReactServerRendering.renderToString(
        <span onClick={cb}>hello world</span>
      );
      expect(EventPluginHub.__getListenerBank()).toEqual({});
    });
    it('should only execute certain lifecycle methods', function() {
      function runTest() {