inspect: Validate that __signature__ is None or an instance of Signature.
Closes #21801.
diff --git a/Lib/test/test_inspect.py b/Lib/test/test_inspect.py
index 1ede3b5..da0572d 100644
--- a/Lib/test/test_inspect.py
+++ b/Lib/test/test_inspect.py
@@ -3048,6 +3048,13 @@
self.assertEqual(lines[:-1], inspect.getsource(module).splitlines())
self.assertEqual(err, b'')
+ def test_custom_getattr(self):
+ def foo():
+ pass
+ foo.__signature__ = 42
+ with self.assertRaises(TypeError):
+ inspect.signature(foo)
+
@unittest.skipIf(ThreadPoolExecutor is None,
'threads required to test __qualname__ for source files')
def test_qualname_source(self):