"""Regression: _lookup_bandwidth must tolerate a non-string gpu_name. It guarded only falsy values; a truthy non-string (e.g. a number from a malformed hardware probe) reached `gpu_name.lower()` and raised AttributeError. """ from services.hwfit.fit import _lookup_bandwidth def test_non_string_returns_none(): assert _lookup_bandwidth(123) is None assert _lookup_bandwidth(["x"]) is None assert _lookup_bandwidth(None) is None def test_known_gpu_resolves(): assert _lookup_bandwidth("NVIDIA GeForce RTX 4090") is not None