Modularizing Legacy Projects Using TDD: Test-Driven Development with XCTest for iOS

© Khaled El-Morabea and Hassaan El-Garem 2021

K. El-Morabea, H. El-GaremModularizing Legacy Projects Using TDDhttps://doi.org/10.1007/978-1-4842-7428-6_7

7. Dependency Injection and Mocks

Khaled El-Morabea¹   and Hassaan El-Garem²

(1)

Giza, Egypt

(2)

Cairo, Egypt

 

Writing tests for a component can be a tedious task if this component depends on another component that has an unpredictable behavior. To test such a component, we need to be able to control this unpredictable behavior. We can do that with the help of a test double. The term test double was first introduced in Gerard Meszaros’s book XUnit Test Patterns. Test double is a generic term for any kind of pretend object used in place of a real object for testing purposes. Another situation in which ...