Linking error for unit testing with XCode 4?

Question

I want to write some logic unit tests for classes in my XCode application. In Xcode 4, I clicked on the project name in the Project Navigator, and from the bottom clicked Add Target. I chose "Cocoa Touch Unit Testing Bundle" under Other, give the new target a "product name" of "tests", and finish.

Because the class I want to test is compiled as part of my existing application target, for my new "tests" target I immediately go to the Build Phases tab and add my existing application target as the only target dependency.

I then go to the created tests.m file, import the class I want to test (below it's ReleasePlanManager, and call one of its methods. But the linker fails with an error like:

Undefined symbols for architecture i386:
  "_OBJC_CLASS_$_ReleasePlanManager", referenced from:
      objc-class-ref in tests.o
ld: symbol(s) not found for architecture i386
collect2: ld returned 1 exit status

So the class cannot be found, even though (from my understanding) adding the application target (which it is a part of) should be sufficient?

Any help would be greatly appreciated. Thanks!

Answer 1

Your test bundle needs extra settings:

• Set Bundle Loader to $(BUILT_PRODUCTS_DIR)/AppName.app/AppName (replacing AppName in both places with your app's name)
• Set Test Host to $(BUNDLE_LOADER)

(If you create a project from scratch and enable unit tests, these are set up for you. But if you add a unit test bundle to an existing project, they're not.)