Description
The macOS-only test failure reported in #3146 went unnoticed for an extended period because the CI matrix runs Ubuntu and Windows only. The failing test (test_modern_post_with_deeply_nested_body_is_rejected_not_a_crash) encodes an assumption about where CPython's recursion guard strikes, and that assumption silently broke on macOS + Python 3.14 — a platform/interpreter combination the matrix never exercised.
Adding macos-latest to the test matrix would have surfaced this at the point it was introduced rather than via a downstream bug report. The failure was deterministic and reproducible across repeated macos-latest runs, so it is a reliable signal, not flaky-runner noise.
Worth noting for scoping: the failure mode is CPython-version-sensitive (pre-3.14 the recursion limit ignores stack size entirely, so the test is deterministic and platform-independent there; on 3.14 the outcome depends on per-thread stack headroom). A macOS matrix leg therefore provides the most value on 3.14+, but including it across the supported range also guards against other platform-specific regressions in the server transport stack.
Context: this was flagged during review of #3147 (which fixes #3146) as the "more valuable half" of that issue — splitting it out so it doesn't get closed along with the PR.
References
AI Disclaimer
Description
The macOS-only test failure reported in #3146 went unnoticed for an extended period because the CI matrix runs Ubuntu and Windows only. The failing test (
test_modern_post_with_deeply_nested_body_is_rejected_not_a_crash) encodes an assumption about where CPython's recursion guard strikes, and that assumption silently broke on macOS + Python 3.14 — a platform/interpreter combination the matrix never exercised.Adding
macos-latestto the test matrix would have surfaced this at the point it was introduced rather than via a downstream bug report. The failure was deterministic and reproducible across repeatedmacos-latestruns, so it is a reliable signal, not flaky-runner noise.Worth noting for scoping: the failure mode is CPython-version-sensitive (pre-3.14 the recursion limit ignores stack size entirely, so the test is deterministic and platform-independent there; on 3.14 the outcome depends on per-thread stack headroom). A macOS matrix leg therefore provides the most value on 3.14+, but including it across the supported range also guards against other platform-specific regressions in the server transport stack.
Context: this was flagged during review of #3147 (which fixes #3146) as the "more valuable half" of that issue — splitting it out so it doesn't get closed along with the PR.
References
AI Disclaimer