Check for Unit-Tests in Objective-C

I’ve been adding some Unit Tests to an iOS App lately, which had both Test Host and Bundle Loader set for the Unit-Testing target. Now executing the unit tests caused the iOS App to launch, and the launch itself interfered with my unit-tests (e.g. real network calls which interfere with your mocked network calls).

I needed a way to stop the launch if we are running in a unit testing scenario. So how do you detect if Unit-Tests are being run in Objective-C ? Turns out it’s extremly simple:

BOOL runningTests = NSClassFromString(@"SenTestCase") != nil;

That’s all you need to check if you are running Unit-Tests - an additional return at the right place and your app stops dead when executing unit tests.

There are a few assumptions about your test targets setup:

• Test Host is set to your iOS App
• Bundle Loader is set to your iOS App

Happy Hacking :)