When using Redux, we can test that our application state changes are working by testing that dispatching actions to the store creates our expected output. In this lesson we will run a few realistic actions back to back (as if the user is using the app) and then test that the state tree looks as we expect it to. These types of tests that ensure all of your redux logic is working as expected give you a lot of value for not too much effort (they test your entire app's state in one big swoop). You may also find it useful to add more granular/individual tests for your reducers and/or actions, which we will cover in other lessons in this course.
NOTE: This lesson assumes you have used Redux. If you are new to Redux, it is recommended that you first watch the Getting Started With Redux course.