Handle strange exceptions raised on attempting to access __set_name__

Author: AlexWaygood

Lib/test/test_typing.py

@@ -7577,6 +7577,22 @@ class NamedTupleClass(NamedTuple):
             normal_exception.__notes__[0].replace("NormalClass", "NamedTupleClass")
         )
 
+    def test_exception_raised_if_accessing_set_name_causes_strange_error(self):
+        class Meta(type):
+            def __getattribute__(self, attr):
+                if attr == "__set_name__":
+                    raise TypeError("NO")
+
+        class VeryAnnoying(metaclass=Meta): pass
+
+        # Sanity check to make sure the test is setup correctly:
+        with self.assertRaises(TypeError):
+            VeryAnnoying.__set_name__
+
+        # The real test here is just that this class creation succeeds:
+        class Foo(NamedTuple):
+            attr = VeryAnnoying()
+
 
 class TypedDictTests(BaseTestCase):
     def test_basics_functional_syntax(self):

Lib/typing.py

@@ -2734,7 +2734,7 @@ def __new__(cls, typename, bases, ns):
                     setattr(nm_tpl, key, val)
                 try:
                     set_name = type(val).__set_name__
-                except AttributeError:
+                except Exception:
                     pass
                 else:
                     try: