`swift test` output is buffered (rather than streamed) for swift-testing tests on Windows

[jmschonfeld]

Description

When running swift test on Windows in a VS Tools CMD Prompt or PowerShell, the results of each test are not output as the tests run. Instead, the prompt outputs text indicating that XCTests (no tests) have started/finished, then no output occurs for a few seconds while tests run, and when tests complete the results of all tests are printed at the same time.

Reproduction

1. Checkout swift-foundation
2. Run swift test

Expected behavior

I'd expect that (like on linux/macOS) each test would print its result in near-realtime as the test completes rather than waiting for all tests to complete before printing results

Environment

Swift version 6.2-dev (LLVM 4197ac1672a278c, Swift acbdfef4f4d71b1)
Target: aarch64-unknown-windows-msvc
Build config: +assertions

→ Testing Library Version: 6.3-dev (e63d542c8248599)
→ Target Platform: aarch64-unknown-windows-msvc

Additional information

No response

[grynspan]

Duplicate of a known SPM issue I believe.