feat: add detail if get_obj_by_attr raise StopIteration (#40)

src/fastapi_toolsets/fixtures/utils.py

@@ -29,9 +29,14 @@ def get_obj_by_attr(
         The first model instance where the attribute matches the given value.
 
     Raises:
-        StopIteration: If no matching object is found.
+        StopIteration: If no matching object is found in the fixture group.
     """
-    return next(obj for obj in fixtures() if getattr(obj, attr_name) == value)
+    try:
+        return next(obj for obj in fixtures() if getattr(obj, attr_name) == value)
+    except StopIteration:
+        raise StopIteration(
+            f"No object with {attr_name}={value} found in fixture '{getattr(fixtures, '__name__', repr(fixtures))}'"
+        ) from None
 
 
 async def load_fixtures(

tests/test_fixtures.py

@@ -744,8 +744,11 @@ class TestGetObjByAttr:
         assert user.username == "alice"
 
     def test_no_match_raises_stop_iteration(self):
-        """Raises StopIteration when no object matches."""
-        with pytest.raises(StopIteration):
+        """Raises StopIteration with contextual message when no object matches."""
+        with pytest.raises(
+            StopIteration,
+            match="No object with name=nonexistent found in fixture 'roles'",
+        ):
             get_obj_by_attr(self.roles, "name", "nonexistent")
 
     def test_no_match_on_wrong_value_type(self):