https://jsfiddle.net/3apqnhmw/

```jsx
class Foo extends React.Component {
  render() {
     return <div>Foo</div>
  }
}

class App extends React.Component {
  render() {
    return Foo
  }
}
```

When `App` returns `Foo` instead of `<Foo />` accidentally, Fiber does not catch this.
render() {
        return <Child><div ref="test" /></Child>;
      }
      componentDidMount() {
        expect(this.refs && this.refs.test).toEqual(undefined);
      }
    }
    class Child extends React.Component {
      render() {
        return <div />;
      }
    }
    ReactTestUtils.renderIntoDocument(<Parent child={<span />} />);
  });
  it('should support new-style refs', () => {
    var innerObj = {};
    var outerObj = {};
    class Wrapper extends React.Component {
      getObject = () => {
        return this.props.object;
      };
      render() {
        return <div>{this.props.children}</div>;
      }
    }
    var mounted = false;
    class Component extends React.Component {