Module "MyApp" not found in UnitTest-Swift

Question

Im trying to test some Swift class (@objc class) in my legacy Objc code. I am importing "UnitTests-Swift.h" in my test classes.

Then I get this error:

Module "MyApp" not found in the autogenerated "UnitTests-Swift.h"

This is whats inside the top part of the "UnitTests-Swift.h"

typedef int swift_int3  __attribute__((__ext_vector_type__(3)));
typedef int swift_int4  __attribute__((__ext_vector_type__(4)));
#if defined(__has_feature) && __has_feature(modules)
@import XCTest;
@import ObjectiveC;
@import MyApp;
@import CoreData;
#endif

I cleaned the project, checked all the relevant flags ("No such module" when using @testable in Xcode Unit tests, Can't use Swift classes inside Objective-C), removed derived data and so on.. No idea of whats happening, but I m quite sure that @import MyApp shouldnt be there..

Can anyone help me with this?

Answer 1

Just got this issue in my project and after the entire day spent on investigation I finally resolved it. Basically this happens because you have cyclic dependency between ObjC and Swift. So in my case it was:

• Swift Protocol with @obj attribute in a main target;
• Swift Class in UnitTest target which inherited this Protocol;
• Import UnitTestTarget-Swift.h in any Objective-C class of your UnitTest target

So fairly simple combination leads to this error. In order to fix this you want either:

• simply make sure that your Swift Class in UnitTest target is private, so it won't get to UnitTestTarget-Swift.h

or

• do not mark your original Swift Protocol as @objc, which will allow you to access your SwiftClass from all ObjectiveC test classes, but those classes won't have any idea about the Swift Protocol.