javascript - 测试 Async Redux Action Jest

Question

我无法从异步 redux 操作中获得正确的输出。我使用 Jest、redux-mock-adapter 和 thunk 作为工具。

根据 redux 关于测试异步 thunk 的文档 (https://redux.js.org/docs/recipes/WritingTests.html#async-action-creators)，我的测试应该返回一个包含两个操作的数组。但是，我的测试只返回第一个操作，而不是应该在成功获取时返回的第二个操作。我想我只是在这里遗漏了一些小东西，但至少可以说这很麻烦。

Redux Action

export const getRemoveFileMetrics = cacheKey => dispatch => {
    dispatch({ type: IS_FETCHING_DELETE_METRICS });
    return axios
        .get("GetRemoveFileMetrics", { params: { cacheKey } })
        .then(response => dispatch({ type: GET_REMOVE_FILE_METRICS, payload: response.data }))
        .catch(err => err);
};

测试

it("getRemoveFileMetrics() should dispatch GET_REMOVE_FILE_METRICS on successful fetch", () => {
        const store = mockStore({});
        const cacheKey = "abc123doremi";
        const removeFileMetrics = {
            cacheKey,
            duplicateFileCount: 3,
            uniqueFileCount: 12,
        };
        const expectedActions = [
            {
                type: MOA.IS_FETCHING_DELETE_METRICS,
            },
            {
                type: MOA.GET_REMOVE_FILE_METRICS,
                payload: removeFileMetrics,
            }
        ];
        mockRequest.onGet(`/GetRemoveFileMetrics?cacheKey=${cacheKey}`).reply(200, removeFileMetrics);
        return store.dispatch(MOA.getRemoveFileMetrics(cacheKey)).then(() => {
            const returnedActions = store.getActions();
            expect(returnedActions).toEqual(expectedActions);
        });
    });

输出

Expected value to equal:
    [{ "type": "IS_FETCHING_DELETE_METRICS" }, { "payload": { "cacheKey": "abc123doremi", "duplicateFileCount": 3, "uniqueFileCount": 12 }, "type": "GET_REMOVE_FILE_METRICS" }]
Received:
    [{ "type": "IS_FETCHING_DELETE_METRICS" }]

Answer 1

我正在使用 jest-fetch-mock 而没有使用 axios。以下是为我工作的 Action 。作为第一步，您可以重构为 async await。对我来说，它只适用于这种方式。

我现在正试图弄清楚如何测试副作用 (showErrorAlert(jsonResponse);)。如果我模拟测试文件顶部的 showErrorAlert 实现(在我的示例中已注释掉)，那么我会遇到与您一样的问题。使用 fetch 的操作由于某种原因不会被触发。

export const submitTeammateInvitation = (data) => {
  const config = {
    //.....
  };

  return async (dispatch) => {
    dispatch(submitTeammateInvitationRequest());

    try {
      const response = await fetch(inviteTeammateEndpoint, config);
      const jsonResponse = await response.json();

      if (!response.ok) {
        showErrorAlert(jsonResponse);
        dispatch(submitTeammateInvitationError(jsonResponse));

        throw new Error(response.statusText);
      }

      dispatch(submitTeammateInvitationSuccess());
    } catch (error) {
      if (process.env.NODE_ENV === 'development') {
        console.log('Request failed', error);
      }
    }
  };
};

测试

import configureMockStore from 'redux-mock-store';
import thunk from 'redux-thunk';

// jest.mock('../../../../_helpers/alerts', ()=> ({ showAlertError: jest.fn() }));

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

......

it('dispatches the correct actions on a failed fetch request', () => {
  fetch.mockResponse(
    JSON.stringify(error),
    { status: 500, statusText: 'Internal Server Error' }
  );

  const store = createMockStore({});
  const expectedActions = [
    {
      type: 'SUBMIT_TEAMMATE_INVITATION_REQUEST',
    },
    {
      type: 'SUBMIT_TEAMMATE_INVITATION_FAILURE',
      payload: { error }
    }
  ];

  return store.dispatch(submitTeammateInvitation(data))
    .then(() => {
      // expect(alerts.showAlertError).toBeCalled();
      expect(store.getActions()).toEqual(expectedActions);
    });
});