Fix marshal's incorrect handling of subclasses of builtin types (backport candidate).

1 files changed, 11 insertions, 0 deletions

diff --git a/Lib/test/test_marshal.py b/Lib/test/test_marshal.py
index 656fc1f..1b2c8b7 100644
--- a/Lib/test/test_marshal.py
+++ b/Lib/test/test_marshal.py
@@ -244,6 +244,17 @@ class BugsTestCase(unittest.TestCase):
         last.append([0])
         self.assertRaises(ValueError, marshal.dumps, head)
 
+    def test_exact_type_match(self):
+        # Former bug:
+        #   >>> class Int(int): pass
+        #   >>> type(loads(dumps(Int())))
+        #   <type 'int'>
+        for typ in (int, long, float, complex, tuple, list, dict, set, frozenset):
+            # Note: str and unicode sublclasses are not tested because they get handled
+            # by marshal's routines for objects supporting the buffer API.
+            subtyp = type('subtyp', (typ,), {})
+            self.assertRaises(ValueError, marshal.dumps, subtyp())
+
 def test_main():
     test_support.run_unittest(IntTestCase,
                               FloatTestCase,