Book Image

Test-Driven iOS Development with Swift - Fourth Edition

By : Dr. Dominik Hauser
Book Image

Test-Driven iOS Development with Swift - Fourth Edition

By: Dr. Dominik Hauser

Overview of this book

Test-driven development (TDD) is a proven way to find software bugs earlier on in software development. Writing tests before you code improves the structure and maintainability of your apps, and so using TDD in combination with Swift 5.5's improved syntax leaves you with no excuse for writing bad code. Developers working with iOS will be able to put their knowledge to work with this practical guide to TDD in iOS. This book will help you grasp the fundamentals and show you how to run TDD with Xcode. You'll learn how to test network code, navigate between different parts of the app, run asynchronous tests, and much more. Using practical, real-world examples, you'll begin with an overview of the TDD workflow and get to grips with unit testing concepts and code cycles. You'll then develop an entire iOS app using TDD while exploring different strategies for writing tests for models, view controllers, and networking code. Additionally, you'll explore how to test the user interface and business logic of iOS apps and even write tests for the network layer of the sample app. By the end of this TDD book, you'll be able to implement TDD methodologies comfortably in your day-to-day development for building scalable and robust applications.
Table of Contents (17 chapters)
Section 1 –The Basics of Test-Driven iOS Development
Section 2 –The Data Model
Section 3 –Views and View Controllers
Section 4 –Networking and Navigation


In this chapter, we have learned how to write tests for calls to CLGeoCoder and how to test the async/await REST API calls of URLSession. We have seen what we need to do in the test method to test whether an error is thrown in an async/await call. In addition, we have learned how to make our network code tests independent from the implementation of server infrastructure. This way we made our tests fast and robust.

You can use the skills gained in this chapter to write tests for the complete network layer of your apps. But you don't have to stop there. The strategies we've covered in this chapter also help to write tests for all kinds of async/await APIs.

In the next chapter, we will put all the code that we wrote up to now together, and finally see the app running on the simulator.