Book Image

Test-Driven iOS Development with Swift - Fourth Edition

By : Dr. Dominik Hauser
5 (1)
Book Image

Test-Driven iOS Development with Swift - Fourth Edition

5 (1)
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

What this book covers

Chapter 1, Your First Unit Tests, sees the first unit tests at work. We write real tests for a fictional blogging app and explore the different kinds of assertions in XCTest, a testing framework from Apple.

Chapter 2, Understanding Test-Driven Development, looks at test-driven development and how it can help us developers to write maintainable code.

Chapter 3, Test-Driven Development in Xcode, brings the insights from the first two chapters together and looks at how test-driven development works in Xcode. You'll learn some tricks and configurations that make Xcode a valuable testing tool.

Chapter 4, The App We Are Going To Build, discusses the app we are going to build in the rest of the book. This chapter ends with setting up the project for the app in Xcode.

Chapter 5, Building a Structure for ToDo Items, shows how to build the model layer of our app. By working on it, you will learn how to write tests for Combine code.

Chapter 6, Testing, Loading, and Saving Data, addresses the fact that the data used in the app needs to be saved and loaded in the file system of the iOS device. In this chapter, we build the class that is responsible for this task.

Chapter 7, Building a Table View Controller for the To-Do Items, shows how to write tests for a table view with a diffable data source. You will learn how to test updates of table view cells and the selection of cells.

Chapter 8, Building a Simple Detail View, explores how to test user interface elements such as labels, buttons, and maps. We also take a look at how to test actions of the user that change the data in the model layer.

Chapter 9, Test-Driven Input View in SwiftUI, shows how to build and test a view created using SwiftUI. In order to be able to test SwiftUI code, we add a third-party testing library to the testing target.

Chapter 10, Testing Networking Code, looks at writing tests for the new async/await APIs of URLSession. This will allow you to write clean tests that simulate the network communication with a fast mock object.

Chapter 11, Easy Navigation with Coordinators, the final chapter, shows how to write tests for navigation between the view controllers of our app. This allows us, finally, to see our small app running on the simulator. We fix the last bugs using TDD and end up with a working app.