如何使用Firebase，redux实施测试并使用玩笑进行反应

Question

我正在测试我的代码操作：

export function fetchAlunos() {
  var itens = [];

  return firebaseDatabase
    .ref('/alunos')
    .on('value', snap => {
      snap.forEach(snapChild => {
        var item = snapChild.val();
        item.key = snapChild.key;

        itens.push(item);
      })

      dispatch(fetchAlunoFinished(itens));
    }, erro => dispatch(fetchAlunoError()))
  }


export function addAluno(aluno) {
  try{
    if (aluno && !aluno.id) {

      firebaseDatabase
        .ref('/alunos')
        .push(aluno)
    } else {
      var id = aluno.id;
      delete aluno.id

      firebaseDatabase
        .ref()
        .child('/alunos/' + id)
        .set(aluno)
    }
  } catch (erro) {
    console.log(erro);
  }

  return fetchAlunos();
}

测试是：

import 'firebase/database';
import thunk from 'redux-thunk'
import * as actions from './../../src/actions/aluno';
import * as types from './../../src/actions/types';
import configureMockStore from 'redux-mock-store'


jest.mock('./../../src/config/db.js', () => {

  const firebasemock = require('firebase-mock');

  const mockdatabase = new firebasemock.MockFirebase();
  const mockauth = new firebasemock.MockFirebase();
  const mocksdk = new firebasemock.MockFirebaseSdk(path => {
    return path ? mockdatabase.child(path) : mockdatabase;
  }, () => {
    return mockauth;
  });

  const firebase = mocksdk.initializeApp(); // can take a path arg to database url
  // optional - expose the mock
  global.firebase = firebase;

  // return the mock to match your export api
  return firebase;
});

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

describe("Action Aluno", () => {
  let store;

  beforeEach(() => {
    store = mockStore({ alunos: [] });
  })

  test("Adicionar aluno", () => {

    spyOn(actions, 'fetchAlunos');

    const expectedAction = {
      type: types.FETCH_ALUNOS
    }

    var newAluno = {
      nome: 'Teste aluno'
    };

    return store.dispatch(actions.addAluno(newAluno)).then(() => {
      console.log('store ==>', store);
      console.log(store.getActions());

      expect(store.getActions()).toEqual(expectedAction);
    })
  });

  test('should create an action to add a todo', () => {
    const alunos = [];
    const expectedAction = {
      type: types.FETCH_ALUNOS,
      alunos
    }

    return store.dispatch(actions.fetchAlunos(alunos)).then(() => {
      console.log('store ==>', store);
      expect(store.getActions()).toEqual(expectedAction);
    })
    // expect(mockFirebaseService).toEqual(expectedAction)
  })
})

但是告诉我这个错误：

动作Aluno     ×Adicionar aluno（45ms）     ×应该创建一个动作来添加待办事项（2毫秒）

●Action Aluno› Adicionar aluno

TypeError: snap.forEach is not a function

   9 |     .ref('/alunos')
  10 |     .on('value', snap => {
> 11 |       snap.forEach(snapChild => {
     |          ^
  12 |         var item = snapChild.val();
  13 |         item.key = snapChild.key;
  14 | 

  at src/actions/aluno.js:11:10
  at Object.dispatch (node_modules/redux-thunk/lib/index.js:11:18)
  at Object.<anonymous> (__tests__/actions/aluno.test.js:50:18)

●动作Aluno›应该创建一个动作来添加待办事项

TypeError: snap.forEach is not a function

   9 |     .ref('/alunos')
  10 |     .on('value', snap => {
> 11 |       snap.forEach(snapChild => {
     |          ^
  12 |         var item = snapChild.val();
  13 |         item.key = snapChild.key;

有人帮助我，在我的搜索中找不到用于测试Firebase的教程。

Answer 1

阅读这篇分为四部分的文章。开始玩笑非常有用且完整。

react-native jest - medium - part1

react-native jest - medium - part2

react-native jest - medium - part3

react-native jest - medium - part4