小编ott*_*tto的帖子

我是 React Hooks 的新手，我想要实现的是测试一个 React 组件（称为 CardFooter），该组件包含对 useEffect 钩子的调用，该钩子被触发并修改了全局上下文变量。

CardFooter.js：

const CardFooter = props => {
  const [localState, setLocalState] = useState({
    attachmentError: false
  });
  const globalContext = useContext(GlobalContext);
  React.useEffect(()=> {
    setLocalState({
    ...localState,
    attachmentError: globalContext.data.attachmentError
  });
 },[globalContext.data.attachmentError]);
}

CardFooter.test.js：

import Enzyme, { shallow } from 'enzyme';    
Enzyme.configure({ adapter: new Adapter() });
describe('<CardFooter  />', () => {
  let useEffect;
  const mockUseEffect = () => {
    useEffect.mockImplementation(f => f());
  };

  useEffect = jest.spyOn(React, "useEffect");
  mockUseEffect(); //

  it('should render correctly with no props.', () …