Fix crash when warning about annotated functions if function is objec…

…t or partial function. (#93)

tests/test_typeguard.py

@@ -1022,6 +1022,24 @@ class Child(Parent):
         assert Child.foo('bar') == 'Child'
         pytest.raises(TypeError, Child.foo, 1)
 
+    def test_decorator_factory_no_annotations(self):
+        class CallableClass:
+            def __call__(self):
+                pass
+
+        def decorator_factory():
+            def decorator(f):
+                cmd = CallableClass()
+                return cmd
+
+            return decorator
+
+        with pytest.warns(UserWarning):
+            @typechecked
+            @decorator_factory()
+            def foo():
+                pass
+
 
 class TestTypeChecker:
     @pytest.fixture

typeguard/__init__.py

@@ -193,16 +193,17 @@ def qualified_name(obj) -> str:
     return qualname if module in ('typing', 'builtins') else '{}.{}'.format(module, qualname)
 
 
-def function_name(func: FunctionType) -> str:
+def function_name(func: Callable) -> str:
     """
     Return the qualified name of the given function.
 
     Builtins and types from the :mod:`typing` package get special treatment by having the module
     name stripped from the generated name.
 
     """
+    # For partial functions and objects with __call__ defined, __qualname__ does not exist
     module = func.__module__
-    qualname = func.__qualname__
+    qualname = getattr(func, '__qualname__', repr(func))
     return qualname if module == 'builtins' else '{}.{}'.format(module, qualname)