Testing React Applications

React Testing Library is a handy utility that adds APIs for working with React components. Next.js doesn't come with them out-of-the-box yarn add. It runs your testing scenarios inside a browser, which means that you can easily test your application as a whole. Cypress tests require having your development server running in the background, thankfully package named start-server-and-test does it automatically. Cypress and Playwright offer very similar functionalities.