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

The origin of TDD

In 1996, Kent Beck, Ward Cunningham, and Ron Jeffries introduced a new software development methodology called Extreme Programming while they were working on the project Comprehensive Compensation System at Chrysler. The word Extreme indicates that the concepts behind Extreme Programming are totally different from the concepts used in software development back then. For many people, these concepts sound extreme even today.

The methodology is based on 12 rules or practices. One of the rules states that developers have to write unit tests and all parts of the software have to be thoroughly tested. All tests have to pass before the software (or a new feature) can be released to customers. The tests should be written before the production code that they test.

This so-called test-first programming led to TDD. As the name suggests, in TDD, tests drive the development. This means that the developer writes code only because there is a test...