Once upon a time we talked about how to initialize and launch view controllers manually. We did that so we could inject our dependencies via the initializer, then unit test our view controllers independently of those components.
Then we talked about how you can inject dependencies while loading your view controllers from the storyboard, instead of manually instantiating them.
We isolate the system under test from its dependencies by using faked versions of those dependencies.
Today, we’ll look at a fake in more detail for unit testing your iOS app.