javascript - 如何在 Jest 中将数据作为上下文传递？

Question

我正在尝试使用 Jest 在 enzyme 测试中传递上下文，as shown in the Airbnb doc ，但上下文返回 undefined。我不确定我在这里做错了什么。

App.js

class App extends Component{
  componentWillMount(){
    console.log("Context in App", this.context) // getting undefined when running test case
  }

  render(){
    return(
      <div>
        Sample Application
      </div>
    )
  }
}

export default App;

App.test.js

import React from 'react';
import { shallow } from 'enzyme';
import App from './App';

describe('App test cases', () => {
  let wrapper;
  let AppContext = {name: "React is Simple"};
   beforeEach(() => {
    wrapper = shallow(<App />, {context: AppContext })
   })
   test('should pass render the component without crashing', () => {
    expect(wrapper).toMatchSnapshot()
   })
})

版本

React: 16.8.1
enzyme: 3.8.0
enzyme-adapter-react-16: 1.7.1

Answer 1

这似乎是一个 open issue for enzyme对于 the new context api .作为解决方法，您可以设置静态 contextTypes :

App.contextTypes = {
  name: PropTypes.string
};

然后您可以根据需要操纵上下文:

shallow(<App />, {context: {name: "React is Simple"}}) // did mount
    .setContext({ name: 'some new context'}); // did update

在您的应用中:

componentDidMount(){
    console.log("Context in App", this.context) 
  }
  componentDidUpdate() {
    console.log(this.context);
  }

希望对您有所帮助。