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)

Behavior-Driven Development

Behavior-Driven Development (BDD) is sort of similar to TDD, but you can focus on testing the behavior of your app instead. The main difference is the way the tests are written. Using XCTest, you mainly use the method name to describe what the test does. BDD frameworks usually allow you to write the expected behavior as a text string and therefore make the tests easier to read.

It is often said that the tests become so clear that people who are not familiar with programming can write them. Here is an example that uses the Quick framework and its matcher framework, Nimble:

class ToDoItemSpec: QuickSpec { 
  override func spec() { 
    describe("to-do item") {
 
             
      it("can be created with a title") { 
        let item = ToDoItem(title: "Test title") 
        expect(item).toNot(beNil()) 
      }
 
       ...