Table Of ContentTest-Driven iOS Development with
Swift 3
Write testable and maintainable code to develop highly-functional iOS apps
Dr. Dominik Hauser
BIRMINGHAM - MUMBAI
Test-Driven iOS Development with Swift 3
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First published: February 2015
Second edition: October 2016
Production reference: 1251016
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Credits
Author Copy Editor
Dr. Dominik Hauser Yesha Gangani
Reviewer Project Coordinator
S Ravi Shankar Sheejal Shah
Commissioning Editor Proofreader
Ashwin Nair Safis Editing
Acquisition Editor Indexer
Reshma Raman Rekha Nair
Content Development Editor Production Coordinator
Parshva Sheth Aparna Bhagat
Technical Editor
Rutuja Vaze
About the Author
Dr. Dominik Hauser completed his Ph.D. from the University of Heidelberg in Physics.
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 turned
himself into a full-time iOS developer, crediting number of successful apps to his name. He
has been a Swift developer since day one and runs a blog on iOS development,
www.swiftandpainless.com.
I would like to thank my wife, Isa. Thank you for all your support during all those years
and especially the last months while I wrote this book. I also want to thank all those great
people in our community. I learned so much by reading excellent blog posts. I proud to be
part of it.
About the Reviewer
S Ravi Shankar is a multi-skilled software consultant with over 17+ years of experience in
IT Industry. Good all-around ability to work in different technologies and extensive
experience in product development, system maintenance and support. A polyglot and a
self-taught programmer with hands on experience in Swift, Objective-C and Java.
It was a pleasure to work with Sheejal and thanks to Packt publishing for giving me this
opportunity.
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Table of Contents
Preface
1
Chapter 1: Your First Unit Tests
6
Building your first automatic unit test 7
What are unit tests? 7
Implementing a unit test example 7
Important built-in assert functions 12
Understanding TDD 15
The TDD workflow – red, green, and refactor 16
Red 16
Green 17
Refactor 17
TDD in Xcode 17
An example of TDD 18
Red – example 1 19
Green – example 1 20
Refactor – example 1 20
Red – example 2 21
Green – example 2 21
Refactor – example 2 22
A recap 24
Finding information about tests in Xcode 24
Test Navigator 24
Tests overview 25
Running tests 27
Running one specific test 27
Running all tests in a test case 28
Running a group of tests 28
The setUp() and tearDown() methods 29
Debugging tests 30
Breakpoint that breaks on test failure 31
The test again feature 32
The advantages of TDD 32
The disadvantages of TDD 33
What to test 34
Summary 35
Chapter 2: Planning and Structuring Your Test-Driven iOS App
36
The task list view 37
The task detail view 39
The task input view 40
The structure of the app 41
The Table View Controller, the delegate, and the data source 41
Table view cells 42
The model 42
Other View Controllers 42
The development strategy 43
Getting started with Xcode 43
Setting up useful Xcode behaviors for testing 44
Useful build behaviors 45
Testing behaviors 45
Summary 47
Chapter 3: A Test-Driven Data Model
48
Implementing the ToDoItem struct 49
Adding a title property 49
Adding an itemDescription property 51
Removing a hidden source of bugs 52
Adding a timestamp property 54
Adding a location property 55
Implementing the Location struct 56
Adding a coordinate property 57
Implementing the ItemManager class 58
Count 58
Adding and checking items 61
Equatable 67
Removing all items 76
Ensuring uniqueness 77
Summary 78
Chapter 4: A Test-Driven View Controller
79
Implementing ItemListViewController 80
Implementing ItemListDataProvider 90
Conducting the first tests 90
Fake objects 96
Using mocks 97
Checking and unchecking items 108
Implementing ItemCell 110
Implementing DetailViewController 117
[ ii ]
Implementing InputViewController 122
Summary 128
Chapter 5: Testing Network Code
129
Implementing tests using a web service 130
Implementing a login request 133
Handling errors 141
Summary 145
Chapter 6: Putting It All Together
146
Connecting parts 147
The initial View Controller 147
Showing the input view 148
Showing the detail view 156
Serialization and deserialization 160
Functional tests 168
Adding a UI test target 169
Recording and testing 169
Summary 175
Chapter 7: Code Coverage and Continuous Integration
176
Enabling code coverage 176
Code coverage in Xcode 177
What code coverage is enough? 180
Continuous integration 180
Installing and setting up Xcode Server 181
Adding bots 186
Automatic deployment with fastlane 190
Installing fastlane 191
Setting up 191
Summary 192
Chapter 8: Where to Go from Here
193
What we have learned so far 193
Integration tests 194
UI tests 194
Behavior-Driven Development 195
TDD in existing projects 196
More information about TDD 197
Summary 197
Index
198
[ iii ]
