How to test Firebase login action (React/Jest)

Question

I'm trying to create a test that will see if signIn has been called, then proceed to the success and error function testing.

I'm using the firebase-mock package here: https://github.com/soumak77/firebase-mock/blob/master/tutorials/auth/authentication.md

Below is my Login action

// Sign in action
export const signIn = (email, password, redirectUrl = ROUTEPATH_DEFAULT_PAGE) => (dispatch) => {
  dispatch({ type: USER_LOGIN_PENDING });

  firebase
    .then(auth => auth.signInWithEmailAndPassword(email, password))
    .catch((e) => {
      console.error('actions/Login/signIn', e);
      // Register a new user
      if (e.code === LOGIN_USER_NOT_FOUND) {
        dispatch(push(ROUTEPATH_FORBIDDEN));
        dispatch(toggleNotification(true, e.message, 'error'));
      } else {
        dispatch(displayError(true, e.message));
        setTimeout(() => {
          dispatch(displayError(false, ''));
        }, 5000);
        throw e;
      }
    })
    .then(res => res.getIdToken())
    .then((idToken) => {
      if (!idToken) {
        dispatch(displayError(true, 'Sorry, there was an issue with getting your token.'));
      }

      dispatch(onCheckAuth(email));
      dispatch(push(redirectUrl));
    });
};

My test:

import configureMockStore from 'redux-mock-store';
import thunk from 'redux-thunk';
import { MockFirebase } from 'firebase-mock';

// Login Actions
import { onCheckAuth, signIn } from 'actions';

// String Constants
import { LOGIN_USER_NOT_FOUND } from 'copy';

const middlewares = [thunk];
const mockStore = configureMockStore(middlewares);

let mockProps;

describe('login actions', () => {
  // console.log('MockFirebase', MockFirebase);
  // console.log('onCheckAuth', onCheckAuth);
  let mockAuth;

  beforeEach(() => {
    mockAuth = new MockFirebase();
    console.log('mockAuth: ==>', mockAuth);

    mockProps = {
      signIn: jest.fn(),
      signOut: jest.fn(),
      checkAuth: jest.fn(),
      createUser: jest.fn(),
      resetPassword: jest.fn(),
      verifyEmail: jest.fn()
    };
  });

  it('signIn should be called', () => {
    const user = {
      email: '[email protected]',
      password: 'abd123'
    };

    signIn(user.email, user.password);
    console.log('signIn', signIn);

    expect(signIn).toHaveBeenCalled();
  });
});

Error message

FAIL client/actions/Login/index.test.js ● login actions › signIn should be called

expect(jest.fn())[.not].toHaveBeenCalled()

jest.fn() value must be a mock function or spy. Received: function: [Function signIn]

at Object.<anonymous> (client/actions/Login/index.test.js:71:29)

Answer 1

I was incorrectly mocking the firebase services function, below is code I got working, however running into a new issue posted here: How to test is code inside of thenable in jest test is getting called?

The following test passes, however not sure that the code inside of the store.dispatch is thenable...

// Mock all the exports in the module.
function mockFirebaseService() {
  return new Promise(resolve => resolve(true));
}

// Since "services/firebase" is a dependency on this file that we are testing,
// we need to mock the child dependency.
jest.mock('services/firebase', () => new Promise(resolve => resolve(true)));

describe('login actions', () => {
  let store;

  beforeEach(() => {
    store = mockStore({});
  });

  it('signIn should call firebase', () => {
    const user = {
      email: '[email protected]',
      password: 'abd123'
    };

    store.dispatch(signIn(user.email, user.password)).then(() => {
      expect(mockFirebaseService).toHaveBeenCalled();
    });
  });
});