Mocks are a great way of preventing AJAX calls in tests, but they can also help you isolate side effects and impurities that can create complicated tests.

As you learned …

Testing can be simple. In fact, it is simple. Well, it is simple until impurities slip in.

Code that would be easy to test becomes a nightmare as soon as you get impure …

Proper state handling in React will make your components simple and maintainable. Poor choices will give you lots of headaches in the long-term.

There are plenty of …