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)

Implementing ItemListDataProvider

In the previous section, we created a class to act as the data source and delegate for the item list table view. In this section, we will implement its properties and methods, but we first need a test case class for ItemListDataProvider.

Conducting the first tests

Open Project Navigator and select the ToDoTests group. Add a new Unit Test Case Class and call it ItemListDataProviderTests. Add the @testable import ToDo import statement and remove the two test template methods.

The table view should have two sections--one for unchecked to-do items and the other for checked items. Add the following test to ItemListDataProviderTests:

func test_NumberOfSections_IsTwo() { 
  let sut = ItemListDataProvider...