`SyntheticEvent.type` is undefined when received by the handler. Or the nativeEvent type for that matter.

Needs to be added in here somewhere: https://github.com/facebook/react/blob/3a4e1dbb5b2957875cab6af11a5e5934e125a0d8/src/test/ReactTestUtils.js#L496

I realize that it's not sustainable to have to set _all_ the possible fields for a simulated event, but the type at least makes sense for verification that you're getting the right _sort_ of event.

var renderedComponent = ReactTestUtils.renderIntoDocument(<Wrapper />);
    var scryResults = ReactTestUtils.scryRenderedDOMComponentsWithClass(
      renderedComponent,
      'x'
    );
    expect(scryResults.length).toBe(1);
  });
  it('can scryRenderedDOMComponentsWithClass with multiple classes', function() {
    var Wrapper = React.createClass({
      render: function() {
        return <div>Hello <span className={'x y z'}>Jim</span></div>;
      },
    });
    var renderedComponent = ReactTestUtils.renderIntoDocument(<Wrapper />);
    var scryResults1 = ReactTestUtils.scryRenderedDOMComponentsWithClass(
      renderedComponent,
      'x y'
    );
    expect(scryResults1.length).toBe(1);
    var scryResults2 = ReactTestUtils.scryRenderedDOMComponentsWithClass(
      renderedComponent,
      'x z'
    );
    expect(scryResults2.length).toBe(1);
    var scryResults3 = ReactTestUtils.scryRenderedDOMComponentsWithClass(
      renderedComponent,
      ['x', 'y']
    );
    expect(scryResults3.length).toBe(1);
    expect(scryResults1[0]).toBe(scryResults2[0]);