模拟内部 axios.create()

Question

我正在使用 jest 和 axios-mock-adapter redux axios

当我使用 axios 使用 --- 创建的实例时，我无法使它们工作 axios.create() 这样：

 import axios from 'axios';

const { REACT_APP_BASE_URL } = process.env;

export const ajax = axios.create({
  baseURL: REACT_APP_BASE_URL,
});

我会在我的 async action creator 中使用它，比如：

 import { ajax } from '../../api/Ajax'

export function reportGet(data) {
  return async (dispatch, getState) => {
    dispatch({ type: REQUEST_TRANSACTION_DATA })

    try {
      const result = await ajax.post(
         END_POINT_MERCHANT_TRANSACTIONS_GET,
         data,
      )
      dispatch({ type: RECEIVE_TRANSACTION_DATA, data: result.data })
      return result.data
    } catch (e) {
      throw new Error(e);
    }
  }
}

这是我的测试文件：

 import {
  reportGet,
  REQUEST_TRANSACTION_DATA,
  RECEIVE_TRANSACTION_DATA,
} from '../redux/TransactionRedux'
import configureMockStore from 'redux-mock-store'
import thunk from 'redux-thunk'
import { END_POINT_MERCHANT_TRANSACTIONS_GET } from 'src/utils/apiHandler'
import axios from 'axios'
import MockAdapter from 'axios-mock-adapter'

const middlewares = [thunk]
const mockStore = configureMockStore(middlewares)
const store = mockStore({ transactions: {} })

test('get report data', async () => {
  let mock = new MockAdapter(axios)

  const mockData = {
    totalSalesAmount: 0
  }

  mock.onPost(END_POINT_MERCHANT_TRANSACTIONS_GET).reply(200, mockData)

  const expectedActions = [
    { type: REQUEST_TRANSACTION_DATA },
    { type: RECEIVE_TRANSACTION_DATA, data: mockData },
  ]

  await store.dispatch(reportGet())
  expect(store.getActions()).toEqual(expectedActions)
})

而且我只得到一个动作 Received: [{"type": "REQUEST_TRANSACTION_DATA"}] 因为 ajax.post 有错误。

我已经尝试了很多方法来模拟 axios.create 在不知道我在做什么的情况下无济于事..任何帮助表示赞赏。

原文由 kyw 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 1

好，我知道了。这是我修复它的方法！我最终 没有 为 axios 做任何模拟库！

在 src/__mocks__ axios 创建一个模拟：

 // src/__mocks__/axios.ts

const mockAxios = jest.genMockFromModule('axios')

// this is the key to fix the axios.create() undefined error!
mockAxios.create = jest.fn(() => mockAxios)

export default mockAxios

然后在您的测试文件中，要点如下所示：

 import mockAxios from 'axios'
import configureMockStore from 'redux-mock-store'
import thunk from 'redux-thunk'

// for some reason i need this to fix reducer keys undefined errors..
jest.mock('../../store/rootStore.ts')

// you need the 'async'!
test('Retrieve transaction data based on a date range', async () => {
  const middlewares = [thunk]
  const mockStore = configureMockStore(middlewares)
  const store = mockStore()

  const mockData = {
    'data': 123
  }

  /**
   *  SETUP
   *  This is where you override the 'post' method of your mocked axios and return
   *  mocked data in an appropriate data structure-- {data: YOUR_DATA} -- which
   *  mirrors the actual API call, in this case, the 'reportGet'
   */
  mockAxios.post.mockImplementationOnce(() =>
    Promise.resolve({ data: mockData }),
  )

  const expectedActions = [
    { type: REQUEST_TRANSACTION_DATA },
    { type: RECEIVE_TRANSACTION_DATA, data: mockData },
  ]

  // work
  await store.dispatch(reportGet())

  // assertions / expects
  expect(store.getActions()).toEqual(expectedActions)
  expect(mockAxios.post).toHaveBeenCalledTimes(1)
})

原文由 kyw 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 2

如果您需要创建在特定测试中模拟 axios 和 create 的 Jest 测试（并且不需要所有测试用例的模拟 axios，如其他答案中所述），您也可以使用：

 const axios = require("axios");

jest.mock("axios");

beforeAll(() => {
    axios.create.mockReturnThis();
});

test('should fetch users', () => {
    const users = [{name: 'Bob'}];
    const resp = {data: users};
    axios.get.mockResolvedValue(resp);

    // or you could use the following depending on your use case:
    // axios.get.mockImplementation(() => Promise.resolve(resp))

    return Users.all().then(data => expect(data).toEqual(users));
});

这是在没有 create 的 Jest 中模拟 Axios 的相同示例的链接。区别在于添加 axios.create.mockReturnThis()

原文由 Saša 发布，翻译遵循 CC BY-SA 4.0 许可协议