Hauser - Test-driven iOS development with Swift 4: write Swift code that is maintainable, flexible, and easily extensible

BIRMINGHAM - MUMBAI

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First published: February 2016

Second edition: October 2016

Third edition: October 2017

Production reference: 1271017

ISBN 978-1-78847-570-9

www.packtpub.com

Dr. Dominik Hauser completed his PhD in physics from the University of Heidelberg. While working as a university professor, he started iOS development in his spare time. His first app on physics has been an astounding success worldwide. Since then, he has turned himself into a full-time iOS developer, with a number of successful apps to his name. He has been a Swift developer since day one and runs a blog on iOS development.

S Ravi Shankar is a multi-skilled software consultant with over 17+ years of experience in IT industry. He has a good all-around ability to work in different technologies and extensive experience in product development, system maintenance, and support. He is a polyglot and a self-taught programmer with hands-on experience in Swift, Objective-C, and Java.

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iOS projects have become bigger and more complex. Many projects have already surpassed desktop applications in their complexity. One important strategy to manage this complexity is through the use of unit tests. By writing tests, a developer can point out the intention of the code and provide a safety net against the introduction of bugs.

By writing tests first (test-driven development), the developer focuses on the problem. This way, they are forced to think about the domain and rephrase a feature request using their own understanding by writing the test. In addition to this, applications are written using TDD only containing code that is necessary to solve the problem.

As a result, the code is clearer, and the developer gains more confidence that the code actually works.

In this book, you will develop an entire iOS app using TDD. You will experience different strategies for writing tests for models, view controller, and networking code.

, Your First Unit Tests , walks you through your first unit tests using Xcode and discusses the benefits of using TDD.

, Planning and Structuring Your Test-Driven iOS App , introduces the app you are going to write through the course of this book and how to set up a project in Xcode.

, A Test-Driven Data Model , discusses the TDD of a data model.

, A Test-Driven View Controller , shows you how to write tests for a view controller, and describes how to use fake objects to isolate micro features for the test.

, Testing Network Code , teaches you to test network code using stubs to fake a server component before it is developed.

, Putting It All Together , walks you through the integration of all the different parts developed in previous chapters and shows the use of functional tests.

, Code Coverage , shows you how to measure the code coverage of your tests using Xcode.

, Where to Go from Here , wraps up and shows you the possible next steps to improve your acquired testing skills.

The following hardware and software is needed to follow the code examples in