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

Implementing the ToDoItem struct

To be useful, to-do items need a minimal set of information. In this section, we will create a structure to hold this information while using tests to guide their development.

A to-do app needs a model class/struct to store information for to-do items:

  1. We will start by adding a new test case to the unit test target. Open the to-do project that we created in the Getting started with Xcode section of Chapter 4, The App We Are Going to Build, and select the ToDoTests group.
  2. Go to File | New | File..., navigate to iOS | Source | Unit Test Case Class, and click on Next. Put in the name ToDoItemTests, make it a subclass of XCTestCase, select Swift as the language, and click on Next.
  3. In the next window, click on Create.
  4. Now, delete the ToDoTests.swift template test case.

Adding a title property

A to-do item needs a title. Follow these steps to add one to our ToDoItem struct:

  1. Open ToDoItemTests.swift and add the following...