如何测试返回函数值

Question

如何测试这个函数的返回值？

handleValidatePassword = (confirmPassword) => {
    const { newPassword } = this.props;
    if (newPassword !== confirmPassword) {
      return <FormattedMessage id="some value" />;
    }
  }

如果条件正确，我需要检查此函数的返回值是否为预期值：(FormattedMessage return span with value === id)

<span> some value </span>

我正在使用浅酶进行测试

Answer 1

如果您使用 jest 或 jasmine f.e.，我个人会使用酶匹配剂。 https://github.com/FormidableLabs/enzyme-matchers/blob/master/packages/jest-enzyme/README.md#tocontainreact

import { shallow } from 'enzyme' 
import Element from './yourpath'

const wrapper = shallow(<Element />); // mount/render/shallow when applicable

//as shallow renders only one level of children components
expect(wrapper).toContainReact(<FormattedMessage id="some value" />);

//or if you want to test actually the span element you should use mount
const wrapper2 = mount(<Element />);
expect(wrapper).toContainReact(<span> some value </span>);