当父方法在 JEST 中抛出错误时，期望子方法抛出错误

Question

• 在方法signup里面，我在嘲笑 firebase.auth().createUserWithEmailAndPassword 并让它抛出 一个error
• 所以现在我希望父方法，即 signup 也应该抛出，因为 signup 方法的 sub-method 已经抛出错误
• 但是测试用例失败了，我在这里缺少什么？

App.js

import firebase from 'firebase/app'
import 'firebase/auth'
import './Init'

const App = {
  firebase: firebase,
  signup: async (email, password) => {
    const userCredential = await App.firebase.auth().createUserWithEmailAndPassword(email, password)
    await userCredential.user.sendEmailVerification()
    return `Check your email for verification mail before logging in`
  },
export default App

App.spec.ts

import myAuthenticationPlugin from 'authenticationPlugin/App'
it('to Throw',async ()=>{
     myAuthenticationPlugin.firebase = {
     auth: jest.fn().mockReturnThis(),
     createUserWithEmailAndPassword: jest.fn(() => {
       throw new Error('Network Error')
     }),
   }
     expect(myAuthenticationPlugin.firebase.auth().createUserWithEmailAndPassword).toThrowError('Network Error')
     expect(await myAuthenticationPlugin.signup).toThrow() // THIS FAILS
    })

错误

 expect(received).toThrow()

    Received function did not throw

      107 |       expect(myAuthenticationPlugin.firebase.auth().createUserWithEmailAndPassword).toThrowError('Network Error')
    > 108 |       expect(await myAuthenticationPlugin.signup).toThrow()
          |                                                   ^
      109 | 
      110 |     })
      111 |   })

Answer 1

这有几个问题：

expect(await myAuthenticationPlugin.signup).toThrow() // THIS FAILS

首先，传递给expect的参数必须是函数，所以这几乎正确：

expect(async () => { await myAuthenticationPlugin.signup() }).toThrow()

...但它也行不通。这是因为.toThrow() 函数用于检测同步错误抛出，而不是用于检查被拒绝的 Promise。你需要使用.rejects 来告诉 Jest 解开 Promise：

await expect(myAuthenticationPlugin.signup()).rejects.toThrow()