As I introduced yesterday, KIF is a tool that enables functional testing of iOS applications. I wanted to go into a little more detail today on KIF’s capabilities by giving you three reasons KIF is awesome. Tomorrow, I’ll present an actual walkthrough of writing a KIF test case or two, so be sure to check back then.
What is KIF?
KIF stands for “keep it functional.” The name does it justice, it’s a test framework totally focused on providing a mechanism to write functional tests for your app. KIF tests hook into your app by interacting with the user interface. Similar to all automated tests of any sort, KIF enables you to write repeatable steps of verification to ensure that certain inputs determine certain outputs. Unlike a unit test where you might instantiate a model object, and then directly call a method, and verify the outcome, in KIF tests you instead write code to literally navigates through your app’s user interface and looks for things on the screen. You’ll never call viewDidLoad() explicitly from a KIF test, but you will instead simulate the tap of a button. In order to find things on the screen, KIF leverages accessibility labels and identifiers on your user interface elements.
Three Reasons KIF is Awesome
There are three main reasons why I like KIF:
- Tests can be written in Swift or Objective-C. For anyone that has experience with the first iteration of UI Automation test cases, THIS IS HUGE. UI Automation was Apple’s original provided tool for developers to write functional tests, and it was lame because you had to write the tests in JavaScript with a poorly documented API.
- Tests are executed as part of a normal old test target. Similarly replacing UI Automation JavaScript testing, THIS IS EVEN HUGER! Being able to execute your tests as a normal target in Xcode means first class citizenship with your build process, and thus more easily enabling repeatability and integration with continuous integration tools. With a single Command-U (the keyboard shortcut to run all tests), you can run both your unit tests and your KIF tests.
- KIFTestCases, the class that you subclass to write your tests, are subclasses of XCTestCase. This means that the same familiar API from writing verification in unit tests applies to KIF tests, no need to learn a new API for making assertions in your KIF tests.
Can KIF Test Swift Code?
For sure! In fact, this is where I got my first introduction to writing Swift code as part of a “real” project. The first Swift code that we started adding into our repositories on my team was in KIF tests. If you’re looking for a way to start introducing Swift code into your Objective-C project, give it a try in your tests.
Wrap Up
I’ve really enjoyed using KIF for my functional tests, and I hope I helped you by explaining why. Tomorrow, I’m excited to walk you through creating your first KIF test.
Happy cleaning.