I am able to use an Xcode project with Precondition Catching to build a library which imports XCTest to add a couple of additional test functions. I had to use the following build settings.
ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES
ENABLE_TESTING_SEARCH_PATHS = YES
SYSTEM_FRAMEWORK_SEARCH_PATHS = $(CORRESPONDING_DEVICE_PLATFORM_DIR)/Developer/Library/Frameworks $(inherited)
This works by expanding the search path to find XCTest but this package named Hela I am not able to apply these same build settings in Package.swift. I know the CORRESPONDING_DEVICE_PLATFORM_DIR build variable will not be defined so I have tried setting it to the correct path manually using using cSettings and cxxSettings but that also does not work.
Is there a way to make this work?