Root problem:
I'm trying to run the tests for in_app_purchase's in the example app. They fail to compile because @import in_app_purchase fails to find that module.

Diagnosis:
I suspect that is because the testspec is missing from the pod invocation in podhelper.rb:

Here is the documentation for adding tests to podspecs: https://guides.cocoapods.org/using/test-specs.html