text: import React from 'react';
  import ReactDOM from 'react-dom';
  import App from './App';
  
  import {applyMiddleware, createStore} from 'redux'
  import {Provider} from 'react-redux'
  
  import reducer from './reducers';
  import thunk from "redux-thunk";
  
  const reduxStore = createStore(reducer, applyMiddleware(thunk));
  
  jest.mock(
      'firebase',
      () => ({
          initializeApp: () => ({
          }),
          database: () => ({
              ref: () => ({
                  once: () => new Promise(() => ({
                      val: () => 'x'
                  }))
              })
          }),
      }),
      {virtual: true}
  );
  
  it('renders without crashing', () => {
      const div = document.createElement('div');
      ReactDOM.render(
          <Provider store={reduxStore}>
              <App/>
          </Provider>
          , div);
  });
  