当我试图监视 window 对象时出现 UnhandledPromiseRejection (jest + nuxt js)

Question

我正在使用 jest 来监视 window 对象来为我的 nuxt js 组件定义我自己的 window.scrollY 值。

我的笑话代码：

const winSpy = jest.spyOn(global, 'window', 'get')
winSpy.mockImplementation(() => ({
  scrollY: 200
}))

它工作正常，但在终端中显示以下错误：

node:internal/process/promises:265
        triggerUncaughtException(err, true /* fromPromise */);
        ^

[UnhandledPromiseRejection: This error originated either by throwing inside of an 
async function without a catch block, or by rejecting a promise which was not handled 
with .catch(). The promise rejected with the reason "TypeError: Cannot read 
properties of undefined (reading 'get')".] {

问题是什么？

谁能帮我解决这个问题？

Answer 1

您需要在 mockImplementation 中包含原始 window 属性：

describe('MyComponent', () => {
  it('reads scrollY', () => {
    const originalWindow = { ...window }
    const windowSpy = jest.spyOn(global, 'window', 'get')
    windowSpy.mockImplementation(() => ({
      ...originalWindow, 
      scrollY: 200,
    }))
    const wrapper = shallowMount(MyComponent)
    expect(wrapper.vm.top).toBe(200)
  })
})

demo

当我试图监视 window 对象时出现 UnhandledPromiseRejection (jest + nuxt js)

UnhandledPromiseRejection when I am trying to spy window object (jest + nuxt js)

vue.js

jestjs

nuxt.js