Is it possible to import the modulename-Swift.h file to another .h file, so that the test target also would compile?
Currently, I was importing the modulename-Swift.h in the one of the headers of the app's target, however, the test target was not able to compile.
When I moved the import statement to the .m file instead, I was able to compile both, the app and the tests.
However, I have to resort to a forward protocol declaration in order to resolve this issue - the modulename-Swift.h file contains a protocol.
So, the question is whether I can import that file in .h file at all?
No, you can't import modulename-Swift.h in a .h file. You'll need to create forward declarations (adding @protocol Something; to your .h) and import the Swift module in the .m file.
Another way to work around this is to declare the protocol conformance in a category in the .m file. More details can be found in this StackOverflow answer: