Book Image

Test-Driven iOS Development with Swift 4 - Third Edition

By : Dr. Dominik Hauser
Book Image

Test-Driven iOS Development with Swift 4 - Third Edition

By: Dr. Dominik Hauser

Overview of this book

Test-driven development (TDD) is a proven way to find software bugs early. Writing tests before you code improves the structure and maintainability of your apps. Using TDD, in combination with Swift 4's improved syntax, means there is no longer any excuse for writing bad code. This book will help you understand the process of TDD and how to apply it to your apps written in Swift. Through practical, real-world examples, you’ll learn how to implement TDD in context. You will begin with an overview of the TDD workflow and then delve into unit-testing concepts and code cycles. You will also plan and structure your test-driven iOS app, and write tests to drive the development of view controllers and helper classes. Next, you’ll learn how to write tests for network code and explore how the test-driven approach—in combination with stubs—helps you write network code even before the backend component is finished. Finally, the book will guide you through the next steps to becoming a testing expert by discussing integration tests, Behavior Driven Development (BDD), open source testing frameworks, and UI Tests (introduced in Xcode 9).
Table of Contents (9 chapters)

Getting started with Xcode

Now, let's start our journey by creating a project that we will implement using TDD.

Open Xcode and create a new iOS project using the Single View Application template. In the options window, add ToDo as the product name, select Swift as language, and check the box next to Include Unit Tests. Let the Use Core Data and Include UI Tests boxes stay unchecked.

Xcode creates a small iOS project with two targets: one for the implementation code and the other for the unit tests. The template contains code that presents a single view on screen. We could have chosen to start with the master-detail application template because the app will show a master and a detail view. However, we have chosen the Single View Application template because it comes with hardly any code. In TDD, we want to have all the implementation code demanded by failing tests.

To take...