Git Repository Tests are hanging on the Windows CI job

[dschaefer2]

Is it reproducible with SwiftPM command-line tools: swift build, swift test, swift package etc?

• Confirmed reproduction steps with SwiftPM CLI. The description text must include reproduction steps with either of command-line SwiftPM commands, swift build, swift test, swift package etc.

Description

We saw this with an attempt last year to parallelize the git checkouts SwiftPM does at the beginning of the resolve step. It has hit again when we parallelized the Git repository tests in Windows CI in the build-using-self script.

Running the tests in parallel greatly improve the CI run times. So for now, I have turned off those tests in Windows when running the build-using-self scripts, but we do need to bring them back.

Two options, find out why it's happening. Which seems so far to only happen in the CI job. All attempt to reproduce locally have failed.

Or we need to find a way to serialize these tests, ensuing only one git operation is running at a time.

I'd prefer the former but it's going to be difficult unless we can reproduce locally so we can debug it or at least quickly try workarounds.

Expected behavior

No response

Actual behavior

No response

Steps to reproduce

No response

Swift Package Manager version/commit hash

No response

Swift & OS version (output of swift --version ; uname -a)

No response

[dschaefer2]

I've tried a number of different incantations of Windows, including physical boxes running Windows 10 and 11 and a VM on may Mac and the nightly and released docker containers, the hang appears to only happen in the docker containers.

Talking with @bkhouri, I think moving these tests to Swift Testing and ensuring they run serialized will be the best way to bring these back.