javascriptreactjsjestjsreact-testing-libraryredux-mock-store

React testing library snapshot testing cannot read store property


I'm trying to create a snapshot test for a component, however, my store keeps coming up as undefined and I cannot figure out why. What do I need to pass into my store to make this correct? I've done snapshot testing with other components that don't require mapStateToProps or withRouter with no issue before.

WorkflowForm.jsx

const mapStateToProps = (state, ownProps) => {
  return {
    ...ownProps,
    userID: state.data.userID,
    userObj: state.ui.userObj
  };
};

export default withRouter(
  connect(mapStateToProps, null)(WorkflowForm)
);

WorkflowForm.test.jsx

import React from 'react';
import renderer from 'react-test-renderer';
import { Provider } from 'react-redux';
import { BrowserRouter } from "react-router-dom";
import  WorkflowForm from "../WorkflowForm";
import { cleanup } from '@testing-library/react';
import configureMockStore from 'redux-mock-store';

afterEach(cleanup);

const mockStore = configureMockStore();
const store = mockStore({
  userID: "121",
  userObj: "Name"
});

describe('Test suits for WorkflowForm', () => {
  it('should match with snapshot', () => {
    const tree = renderer
      .create(
        <Provider store={store}>
          <BrowserRouter>
            <WorkflowForm />
          </BrowserRouter>
        </Provider>
      )
      .toJSON();
    expect(tree).toMatchSnapshot();
   });
});

This is the error I get when I run the test

TypeError: Cannot read property 'userID' of undefined

      392 |   return {
      393 |     ...ownProps,
    > 394 |     userID: state.data.userID,
          |                        ^
      395 |     userObj: state.ui.userObj
      396 |   };
      397 | };

Solution

  • You didn't provide the state to mocked store correctly. It should be:

    const store = mockStore({
      data: { userID: '121' },
      ui: { userObj: 'Name' },
    });