Jest 报告 componentDidMount 中未调用来自酶浅层组件的方法

Question

所以我有一个通用的 class 组件：

import React, { Component } from "react";

export default class CompTest extends Component {
  someFunc() {}

  componentDidMount() {
    this.someFunc();
  }

  render() {
    return <div>Hey</div>;
  }
}

我想检查 someFunc 是否至少被调用一次（在 componentDidMount 内）

describe("<CompTest /> componendDidMount", () => {
  it("should call someFun()", () => {
    const wrapper = shallow(<CompTest />);
    const instance = instance();
    jest.spyOn(instance, "someFun");

    expect(instance.someFunc).toHaveBeenCalledTimes(1);
  });
});

但是我得到： Expected mock function to have been called one time, but it was called zero times.

根据酶 v3 文档：As of Enzyme v3, the shallow API does call React lifecycle methods such as componentDidMount and componentDidUpdate.

我的测试有什么问题？谢谢。

Answer 1

（此处为酶维护者）

问题是在原始文件已经传递到渲染树后，您正在监视 someFunc 方法。试试这个：

describe("<CompTest /> componendDidMount", () => {
  it("should call someFun()", () => {
    jest.spyOn(CompTest.prototype, 'someFunc');
    const wrapper = shallow(<CompTest />);

    expect(wrapper.instance().someFunc).toHaveBeenCalledTimes(1);
  });
});

Jest 报告 componentDidMount 中未调用来自酶浅层组件的方法

Jest reports that a method from a enzyme shallowed component has not been called in componentDidMount

testing

reactjs

jestjs

react-native

enzyme