Most apps have more than one view controller. Besides interactions within a view controller, we ought to test navigation from one view controller to the next.
Going from one view controller to next is part of what we want to test. But what’s even more interesting is that we can test the data the first view controller sends to the next one.
In this chapter, you’ll learn how to write unit tests for code-based navigation and segue-based navigation. In fact, you’ll be able to test this navigation without manual tests or UI tests.