jest-environment import React from 'react' ; import { renderToString as mount } from 'react-dom/server' ; import { Snackbar } from './snackbar' ; describe ( 'Snackbar' , ( ) => { it ( 'renders' , ( ) => { mount ( < Snackbar open onClose = { ( evt ) => { } } message = "This is a new message" action = { < div / > } />); } ) ; } ) ;