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)


In this chapter, we looked at how to implement a view controller with a table view using TDD. We split the table view controller into code that manages the view hierarchy and code for the data source, and the delegate of the table view.

We discussed how to write tests to drive the development of subviews, outlets, and actions, and how to use fake objects to isolate the microfeature to be tested. The usage of mock objects allowed us to create fast, isolated, and reliable tests. This way, we were able to write tests for the table view cell without the need to instantiate the real data source of the table view.

Next, we implemented the detail view controller using TDD. We added MapKit to the project in order to show the location of the to-do item in case a user added an address.

Finally, we wrote tests to drive the implementation of the input view controller. We also looked...