Chapter 9: Test-Driven Input View in SwiftUI

In 2019, Apple introduced SwiftUI as a new way to build user interfaces for apps on Apple platforms. In contrast to user interfaces built with UIKit, SwiftUI views are a function of some kind of state. As a result, testing such views can be very easy. In a test, we would have to set the state and assert that the expected user interface elements are present.

Unfortunately, the engineers in charge at Apple believe that there is no value in testing user interfaces. They believe that to prove the user interface looks and works as expected, it's enough to run the app and check with your eyes. This might be true for an app as simple as the one we are building in this book. But, if you have a look in the App Store, you will find most of the apps (if not all) are way more complicated. Usually, apps consist of many views and some of them are only visible in some rare cases. Ensuring that those views work for all input values and environment...