Test a Render Prop!

two-wrappers.jsx

describe('when <App /> renders', () => {
  const wrapper = shallow(<App />);
  const mouseWrapper = shallow(
    wrapper.find(Mouse).prop('render')({ x: 0, y: 0 })
  );

  it('should render a string containing the coordinates', () => {
    expect(mouseWrapper.equals(<h1>The mouse position is (0, 0)</h1>)).toBe(
      true
    );
  });
});