javascript 在 React 中使用 Jest 测试函数的返回值
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Test return value of function with Jest in React
提问by Modular Integration
How would I test the return value in the "doSomethingFancy" function in this React code? I tried to find a super simple example and couldn't find anything. So I would like to write a test that checks that the number 2 is returned. I know it doesn't really return to anything as I wrote this as an example so I can learn how to write tests for my React application. Any help would be greatly appreciated.
我将如何测试此 React 代码中“doSomethingFancy”函数的返回值？我试图找到一个超级简单的例子，但找不到任何东西。所以我想编写一个测试来检查是否返回了数字 2。我知道它并没有真正返回任何东西，因为我将它作为示例编写，因此我可以学习如何为我的 React 应用程序编写测试。任何帮助将不胜感激。
import React from 'react';
class FancyStuff extends React.Component {
render() {
return <div>
<h1>
Hello, {this.props.name}
</h1>
<button onClick={this.doSomethingFancy}>
Add 1 + 1!
</button>
</div>;
}
doSomethingFancy(e) {
e.preventDefault();
let value = 1 + 1;
return value;
}
};
export default FancyStuff;
回答by EMC
If you need to access a class method in your test, it will be available as a property on the return of the instance method for your wrapper.
如果您需要访问测试中的类方法，它将作为包装器的实例方法返回时的属性提供。
const wrapper = shallow(<MyComponent />);
expect(wrapper.instance().doSomethingFancy()).toEqual(true);
