From 04f8aa18335e5ed76e4e099027a6841f986eb091 Mon Sep 17 00:00:00 2001
From: Afonso Coutinho <afonso@omelhorsite.pt>
Date: Wed, 3 Jun 2026 06:11:10 +0100
Subject: [PATCH] fix: _lookup_bandwidth crashes on a truthy non-string
 gpu_name (#1641)

---
 services/hwfit/fit.py                   |  2 +-
 tests/test_hwfit_bandwidth_nonstring.py | 16 ++++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)
 create mode 100644 tests/test_hwfit_bandwidth_nonstring.py

diff --git a/services/hwfit/fit.py b/services/hwfit/fit.py
index 9e80ced..fb0e006 100644
--- a/services/hwfit/fit.py
+++ b/services/hwfit/fit.py
@@ -61,7 +61,7 @@ CONTEXT_TARGET = {
 
 
 def _lookup_bandwidth(gpu_name):
-    if not gpu_name:
+    if not isinstance(gpu_name, str) or not gpu_name:
         return None
     gn = gpu_name.lower()
     for key in _BW_KEYS_SORTED:
diff --git a/tests/test_hwfit_bandwidth_nonstring.py b/tests/test_hwfit_bandwidth_nonstring.py
new file mode 100644
index 0000000..4b5e496
--- /dev/null
+++ b/tests/test_hwfit_bandwidth_nonstring.py
@@ -0,0 +1,16 @@
+"""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