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)
1
Section 1 –The Basics of Test-Driven iOS Development
5
Section 2 –The Data Model
9
Section 3 –Views and View Controllers
13
Section 4 –Networking and Navigation

Finding information about tests in Xcode

With Xcode 5 and the introduction of XCTest, unit testing became tightly integrated into Xcode. Apple added many UI elements to navigate to tests, run specific tests, and find information about failing tests. Over the years, they improved the integration further. One key element here is the test navigator.

Test navigator

To open the test navigator, click the diamond with the minus sign in the navigator panel or use the shortcut 6:

Figure 3.1 – The test navigator in Xcode

The test navigator shows all tests in the open project or workspace. In the preceding screenshot, you can see the test navigator for our demo project. In the project, there are two test targets, one for the unit tests and one for the UI tests. For complex apps, it can be useful to have more than one unit tests target, but this is beyond the scope of this book. The number of tests is shown right behind the name of the test target...