Unit test for the Counter component

Counter.test.jsx

import React from 'react';
import Counter from './Counter';
import {Provider} from 'react-redux';
import configureStore from 'redux-mock-store';
import {render, cleanup, fireEvent} from 'react-native-testing-library';

afterEach(cleanup);

describe('<Counter />', () => {
  // configureStore expects a list of middlewares
  const mockStore = configureStore([]);
  
  it('should display current count', () => {
    const store = mockStore({count: 5});
    const rendered = render(
      <Provider store={store}><Counter /></Provider>
    );
    const textComponent = rendered.getByTestId('text');
    
    expect(textComponent.props.children).toContain(5);
  });
  
  it('should dispatch increment action', () => {
    const store = mockStore({count: 5});
    const rendered = render(
      <Provider store={store}><Counter /></Provider>
    );
    const buttonComponent = rendered.getByTestId('button');
    
    fireEvent(buttonComponent, 'press');
    
    // This will return all actions dispatched on this store
    const actions = store.getActions();
    expect(actions.length).toBe(1);
    expect(actions[0].type).toEqual('INCREMENT');
  });
});