redux-mock-store

redux-mock-store (GitHub: arnaudbenard/redux-mock-store, License: MIT, npm: redux-mock-store)

When you are working on an application with a Redux architecture and you want to test if your actions triggered correctly. Doing this with the default Redux store is a very hard thing. In the project I recently joined we solve this problem by using redux-mock-store, which stores the actions that got triggered. By suppling a getActions() method we can access the previously called actions in the form of an Array.

By example:

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

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

it('should dispatch action', () => {
  const getState = {};
  const addTodo = { type: 'ADD_TODO' };

  const store = mockStore(getState);
  store.dispatch(addTodo);

  const actions = store.getActions();

  expect(actions).toEqual([addTodo]);
});

it('should execute promise', () => {
    function success() {
      return {
        type: 'FETCH_DATA_SUCCESS'
      };
    }

    function fetchData() {
      return dispatch => {
        return fetch('/users.json')
          .then(() => dispatch(success()));
      };
    }

    const store = mockStore({});

    return store.dispatch(fetchData())
      .then(() => {
        expect(store.getActions()[0]).toEqual(success())
      });
})

In the Redux docs you can find a more extensive explanation and best best practices on how to approach this problem.