exposing getters breaks mocks with es6 imports

[phra]

[REQUIRED] Step 2: Describe your environment

• Operating System version: linux
• Firebase SDK version: 3.16.0
• Library version: 5.5.1
• Firebase Product: auth, database

[REQUIRED] Step 3: Describe the problem

i use this technique to mock dependencies imported via es6 imports without having a dependency injection mechanism.

#106 introduces getters for main modules, effectively breaking the cited technique.

Relevant Code:

source.ts

import { auth, credential, database, firestore, initializeApp, ServiceAccount } from 'firebase-admin'

source.spec.ts

import * as admin from 'firebase-admin'

describe('App', async () => {
  beforeEach(async () => {
    spyOn(admin, 'initializeApp')

    spyOn(admin, 'auth' as any).and.returnValue({
      initializeApp: jest.fn(),
      verifyIdToken: jest.fn().mockReturnValue(Promise.resolve({ uid: 'UID' })),
      getUser: jest.fn().mockReturnValue(Promise.resolve({
        uid: 'UID',
        displayName: 'displayName',
        email: 'email',
      })),
    })

    spyOn(functions, 'config' as any).and.returnValue({
      firebase: {},
      sendgrid: {
        apikey: 'apikey',
      },
    })

    spyOn(mail, 'send').and.returnValue(Promise.resolve(void 0))
  })

  describe('/hello-world request', async () => {
    // tslint:disable-next-line:no-empty
    beforeEach(async () => { })

    // tslint:disable-next-line:no-empty
    afterEach(async () => { })

    it('should fail if anonymous user', async () => {
      const [err, res] = await to(anonymousRequest((FUNCTIONS as any).default, '/hello-world'))
      expect(err).toBeFalsy()
      expect(res.status).toBe(403)
      expect(res.text).toBe('Unauthorized')
    })

    it('works', async () => {
      const [err, res] = await to(request((FUNCTIONS as any).default, '/hello-world'))
      expect(err).toBeFalsy()
      expect(res.status).toBe(200)
      expect(res.text).toBe('"Hello from Firebase!"')
    })
  })

Result

running tests results in this errors:

  ● App › /hello-world request › should fail if anonymous user

    TypeError: Cannot set property auth of #<FirebaseNamespace> which has only a getter
      
      at SpyRegistry.spyOn (node_modules/jest-jasmine2/build/jasmine/spy_registry.js:127:21)
      at Object.<anonymous> (__tests__/index.spec.ts:44:5)
          at Generator.next (<anonymous>)
      at __tests__/index.spec.ts:7:71
          at new Promise (<anonymous>)
      at Object.<anonymous>.__awaiter (__tests__/index.spec.ts:3:12)
      at Object.beforeEach (__tests__/index.spec.ts:41:25)

  ● App › /hello-world request › should fail if anonymous user

    Firebase config variables are not available. Please use the latest version of the Firebase CLI to deploy this function.
      
      at init (node_modules/firebase-functions/lib/config.js:51:15)
      at Object.config (node_modules/firebase-functions/lib/config.js:29:9)
      at Timeout.Object.<anonymous>.setTimeout [as _onTimeout] (index.ts:58:8)
      at ontimeout (timers.js:475:11)
      at tryOnTimeout (timers.js:310:5)
      at Timer.listOnTimeout (timers.js:270:5)

  ● App › /hello-world request › works

    TypeError: Cannot set property auth of #<FirebaseNamespace> which has only a getter
      
      at SpyRegistry.spyOn (node_modules/jest-jasmine2/build/jasmine/spy_registry.js:127:21)
      at Object.<anonymous> (__tests__/index.spec.ts:44:5)
          at Generator.next (<anonymous>)
      at __tests__/index.spec.ts:7:71
          at new Promise (<anonymous>)
      at Object.<anonymous>.__awaiter (__tests__/index.spec.ts:3:12)
      at Object.beforeEach (__tests__/index.spec.ts:41:25)

  ● App › /hello-world request › works

    expect(received).toBe(expected)
    
    Expected value to be (using ===):
      200
    Received:
      500
      
      at Object.<anonymous> (__tests__/index.spec.ts:81:26)
          at Generator.next (<anonymous>)
      at fulfilled (__tests__/index.spec.ts:4:56)
          at <anonymous>
      at process._tickCallback (internal/process/next_tick.js:188:7)

[google-oss-bot]

Hmmm this issue does not seem to follow the issue template. Make sure you provide all the required information.

[phra]

a potential solution is cited here: https://stackoverflow.com/a/33169197

[hiranya911]

spyOnProperty() is now the recommended way to mock/stub Admin SDK namespace methods when using Jasmine. There are equivalent mocking techniques for Sinon. See #122 for a related discussion and code samples.