Testing Redux
Unit testing Redux is a very straightforward process. There are two primary units:
Reducers are pure functions that lend themselves well to testing.
Actions trigger changes in a Redux system. There are two broad categories of actions: synchronous (which are quite simple to test) and asynchronous (which are slightly more involved).
The examples below should provide you with a strong foundation for testing Redux applications.
原文: https://angular-2-training-book.rangle.io/handout/testing/redux/