can’t run TestFoundation target in swift-corelibs-foundation repository

[kaijiemu]

I am starting contributing Swift Foundation framework. I am using swift-corelibs-foundation repository by following this guide: swift-corelibs-foundation/GettingStarted.md at main · apple/swift-corelibs-foundation · GitHub 6

But it is failed when I try to run TestFoundation:

What can I do about it？Thanks

[YOCKOW]

Unfortunately, there are bugs to build TestFoundation on macOS.
Not only SR-12177, but also...

also cannot be compiled with the default toolchain, since String.swift uses the @_spi feature to call String(_cocoaString:) and compiling with the default toolchain does not expose the required API.

https://forums.swift.org/t/ci-not-testing-foundation-overlay/51595.

[YOCKOW]

Ah, it's worse than I expected.
The reason why kCF*s become ambiguous is because Xcode is trying to load modulemaps of CoreFoundation twice: the one in Xcode's SDK and the repo's one.
It seems that this problem occurs no matter which toolchain is used.

[Fidetro]

I have successfully compiled SwiftFoundation, and then encountered the same error.
I have tried the methods mentioned here https://forums.swift.org/t/cant-run-testfoundation-target-in-swift-corelibs-foundation-repository/50360/7, but still can't solve

Does this problem still exist?

[parkera]

This is one of the reasons we decided we couldn't really support building the swift-corelibs-foundation module for macOS -- there is just an unresolvable ambiguity with the system frameworks. XCTest, for example, winds up causing a cycle.