如题，举个例子：

// ListItem.tsx interface Props {     onTouchStart: (e: React.TouchEvent) => void; }  const ListItem: React.FC<Props> = (props) => {     const handleTouchStart = (e: React.TouchEvent) => {         // 在组件内部函数调用传入的函数         props.onTouchStart(e);         // 执行一些其他操作     }      return <div onTouchStart={handleTouchStart}></div>; }  export default ListItem; 

// ListItem.test.tsx import { createElement } from 'rax'; import renderer from 'rax-test-renderer';  it('Test ListItem TouchStart', () => {     const mockFunc = jest.fn();     const component = renderer.create(<ListItem onTouchStart={mockFunc} />)     const tree = component.toJSON();     tree.eventListeners.touchstart();     // 报错     expect(tree.eventListeners.touchstart).toHaveBeenCalled(); }) 

expect(received).toHaveBeenCalled()      Matcher error: received value must be a mock or spy function      Received has type:  function     Received has value: [Function handleTouchStart] 

怎么在测试用例中测试传入props的函数是否存在？ 怎么在测试用例中测试传入props的函数是否被调用？