👀 Views: 1965 💬 Answers: 1 📅 Created: 2025-06-21

javascript react redux jest testing JavaScript

I'm confused about I'm dealing with I'm sure I'm missing something obvious here, but This might be a silly question, but I'm having trouble writing unit tests for my asynchronous actions using Redux Thunk in my React app..... Specifically, when I try to test an action creator that fetches data from an API, the promise returned by the action seems to resolve before the mocked API call completes, which leads to inconsistent results in my tests. Here's the relevant code for my action creator: ```javascript import axios from 'axios'; export const fetchData = () => async (dispatch) => { dispatch({ type: 'FETCH_DATA_REQUEST' }); try { const response = await axios.get('https://api.example.com/data'); dispatch({ type: 'FETCH_DATA_SUCCESS', payload: response.data }); } catch (behavior) { dispatch({ type: 'FETCH_DATA_FAILURE', payload: behavior.message }); } }; ``` And here's how I'm trying to test it using Jest and a mock for axios: ```javascript import configureMockStore from 'redux-mock-store'; import thunk from 'redux-thunk'; import axios from 'axios'; import { fetchData } from './dataActions'; const middlewares = [thunk]; const mockStore = configureMockStore(middlewares); jest.mock('axios'); describe('fetchData actions', () => { it('creates FETCH_DATA_SUCCESS when fetching data has been done', async () => { const data = { name: 'John Doe' }; axios.get.mockResolvedValue({ data }); const expectedActions = [ { type: 'FETCH_DATA_REQUEST' }, { type: 'FETCH_DATA_SUCCESS', payload: data }, ]; const store = mockStore({}); await store.dispatch(fetchData()); const actions = store.getActions(); expect(actions).toEqual(expectedActions); }); }); ``` However, when running this test, I get the following behavior: ``` Expected: [ { type: 'FETCH_DATA_REQUEST' }, { type: 'FETCH_DATA_SUCCESS', payload: { name: 'John Doe' } } ] Received: [ { type: 'FETCH_DATA_REQUEST' }, { type: 'FETCH_DATA_FAILURE', payload: 'Network behavior' } ] ``` It seems like the mock for axios isn't being used as expected. I've also tried using `mockImplementation` instead of `mockResolvedValue`, but that led to the same failure. I'm using Jest version 27 and Redux Thunk version 2.4.1. How can I ensure that my mock behaves correctly in this async testing scenario? I'm working on a API that needs to handle this. Any ideas what could be causing this? For context: I'm using Javascript on Linux. Has anyone dealt with something similar? I'm open to any suggestions.