无法在Vue 3 setup()内部执行spyOn函数

Question

如何使用Jest编写一个调用resetTimer并检查是否也调用了startTimer的测试？

代码：

setup () {
    const startTimer = () => {
        // ...
    };
    const resetTimer = () => {
        startTimer();
    };
    return {
        startTimer,
        resetTimer
    }

测试：

import { shallowMount } from '@vue/test-utils';
import Overlay from '@/components/Overlay.vue';
const wrapper = shallowMount(Overlay);
it('resetTimer should call startTimer', () => {
    const spy = jest.spyOn(wrapper.vm, 'resetTimer');
    wrapper.vm.startTimer();
    expect(spy).toHaveBeenCalled();
});

结果：

TypeError: object.hasOwnProperty is not a function
      187 |
      188 |     it('resetTimer should call startTimer', () => {
    > 189 |         const spy = jest.spyOn(wrapper.vm, 'resetTimer');
          |                          ^
      190 |         wrapper.vm.startTimer();
      191 |         expect(spy).toHaveBeenCalled();
      192 |     });

谢谢！

Answer 1

找到了一个临时解决方案，虽然不是最好的，但至少可以让您检查是否调用了函数。

import { mount } from '@vue/test-utils';
import Component from './Component.vue';
describe('Component', () => {
  it('should call foo', () => {
    Component.created = function () {
      this.foo = jest.fn(this.foo);
    };
    const component = mount(Component);
    component.find('div').trigger('click');
    component.vm.foo();
    expect(component.vm.foo).toHaveBeenCalled();
    delete Component.created;
  });
});