Merged revisions 84495-84496 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k

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  r84495 | antoine.pitrou | 2010-09-04 19:40:21 +0200 (sam., 04 sept. 2010) | 4 lines

  Issue #1100562: Fix deep-copying of objects derived from the list and dict types.
  Patch by Michele Orrù and Björn Lindqvist.
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  r84496 | antoine.pitrou | 2010-09-04 19:40:51 +0200 (sam., 04 sept. 2010) | 3 lines

  Fix Björn's name in ACKS.
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diff --git a/Lib/test/test_copy.py b/Lib/test/test_copy.py
index e3503c4..6b64f10 100644
--- a/Lib/test/test_copy.py
+++ b/Lib/test/test_copy.py
@@ -526,6 +526,26 @@
         self.assertEqual(x.foo, y.foo)
         self.assertTrue(x.foo is not y.foo)
 
+    def test_deepcopy_dict_subclass(self):
+        class C(dict):
+            def __init__(self, d=None):
+                if not d:
+                    d = {}
+                self._keys = list(d.keys())
+                dict.__init__(self, d)
+            def __setitem__(self, key, item):
+                dict.__setitem__(self, key, item)
+                if key not in self._keys:
+                    self._keys.append(key)
+        x = C(d={'foo':0})
+        y = copy.deepcopy(x)
+        self.assertEqual(x, y)
+        self.assertEqual(x._keys, y._keys)
+        self.assertTrue(x is not y)
+        x['bar'] = 1
+        self.assertNotEqual(x, y)
+        self.assertNotEqual(x._keys, y._keys)
+
     def test_copy_list_subclass(self):
         class C(list):
             pass