React Testing Library

With an end to end test, you kind of look from the outside on the entire system as a black box. This test has to know something about the framework that is rendering for instance. So it's used two types of tests: one where you want to be safe and the other to exert some new requirements on the system which is more specific. I would use Excel in an architecture to fake out all of the IO. And if you use functional components, if you use React books, then the entire rendering process is synchronous. The difference between them is that query and get by are synchronous and find by is asynchronous.