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

Implementing the Location struct

In the previous section, we added a struct to hold information about the location. We will now add tests to make sure that Location has the required properties and initializer.

These tests could be added to ToDoItemTests, but they are easier to maintain when the test classes mirror the implementation classes/structs. So, we need a new test case class.

Open the Project navigator, select the ToDoTests group, and add a unit test case class called LocationTests. Make sure that you go to iOS | Source | Unit Test Case Class since we want to test the iOS code, and Xcode sometimes navigates to OS X | Source.

Set up the editor to show LocationTests.swift on the left-hand side and Location.swift in the Assistant Editor on the right-hand side. In the test class, add @testable import ToDo and remove the testExample() and testPerformanceExample() template tests.

Adding a coordinate property

The location of a to-do item will be used in the app to show...