prevent unacceptable bases from becoming bases through multiple inheritance (#24806)
diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
index 9a60a12..adce6e5 100644
--- a/Lib/test/test_descr.py
+++ b/Lib/test/test_descr.py
@@ -3735,6 +3735,37 @@
else:
assert 0, "best_base calculation found wanting"
+ def test_unsubclassable_types(self):
+ with self.assertRaises(TypeError):
+ class X(type(None)):
+ pass
+ with self.assertRaises(TypeError):
+ class X(object, type(None)):
+ pass
+ with self.assertRaises(TypeError):
+ class X(type(None), object):
+ pass
+ class O(object):
+ pass
+ with self.assertRaises(TypeError):
+ class X(O, type(None)):
+ pass
+ with self.assertRaises(TypeError):
+ class X(type(None), O):
+ pass
+
+ class X(object):
+ pass
+ with self.assertRaises(TypeError):
+ X.__bases__ = type(None),
+ with self.assertRaises(TypeError):
+ X.__bases__ = object, type(None)
+ with self.assertRaises(TypeError):
+ X.__bases__ = type(None), object
+ with self.assertRaises(TypeError):
+ X.__bases__ = O, type(None)
+ with self.assertRaises(TypeError):
+ X.__bases__ = type(None), O
def test_mutable_bases_with_failing_mro(self):
# Testing mutable bases with failing mro...