// <button ref={(node) => this.button = node}>...</button>const node = this.button;ReactTestUtils.Simulate.click(node);// <input ref={(node) => this.textInput = node} />const node = this.textInput;node.value = 'giraffe';ReactTestUtils.Simulate.change(node);ReactTestUtils.Simulate.keyDown(node, {key: "Enter", keyCode: 13, which: 13});