/te-ci pytorch L1

Greptile Summary

This PR fixes a misplaced pytest.skip() call introduced in #2691. The NVFP4 availability guard was placed inside _test_nvfp4_partial_cast_matches_full, a worker function that runs inside a torch.distributed.run subprocess — completely outside the pytest process. Calling pytest.skip() there raised a BaseException that was uncaught, causing the subprocess to exit non-zero and subprocess.run(..., check=True) to throw subprocess.CalledProcessError, making the test fail on machines without NVFP4 instead of skipping it.

The fix moves the guard to test_nvfp4_partial_cast_matches_full, which runs directly under pytest, so pytest.skip() is handled correctly and the subprocess is never launched on unsupported hardware.

• The root cause is correctly identified: pytest.skip() must only be called from code running under the pytest process.
• The worker function _test_nvfp4_partial_cast_matches_full is only reachable via the subprocess launched by the now-guarded test function, so removing the check from the worker is safe.
• No other code paths call _test_nvfp4_partial_cast_matches_full directly.
• Change is minimal and targeted with no side-effects on other tests.

Confidence Score: 5/5

• This PR is safe to merge; it is a small, well-scoped bug fix with no risk of regressions.
• The change is a single-file, four-line relocation of a pytest.skip() call from a subprocess worker to the correct pytest-context test function. The logic is sound, the fix is the minimal correct solution, and there are no new dependencies or side-effects introduced.
• No files require special attention.

Important Files Changed

Sequence Diagram

sequenceDiagram
    participant pytest as pytest runner
    participant T as test_nvfp4_partial_cast_matches_full
    participant SP as subprocess (torch.distributed.run)
    participant W as _test_nvfp4_partial_cast_matches_full (worker)

    pytest->>T: invoke test

    alt NVFP4 not available (NEW behaviour)
        T->>T: is_nvfp4_available() → False
        T->>pytest: pytest.skip(reason)
        Note over SP,W: subprocess never launched
    else NVFP4 available
        T->>SP: subprocess.run(..., check=True)
        SP->>W: run_parallel_nvfp4_partial_cast_test()
        W->>W: distributed quantisation assertions
        W-->>SP: success / AssertionError
        SP-->>T: exit 0 / non-zero
        T-->>pytest: pass / CalledProcessError
    end

_{Last reviewed commit: c1fb5d7}