Add regression test for SF bug #476616 -- make sure copy of a derived class

does not share data with the original.

diff --git a/Lib/test/test_userdict.py b/Lib/test/test_userdict.py
index 49be8c65b9d8f075e4bec8d372982cae41bd6a61..0f2fbb8f8e4e89dc75001bfcdffd0ca95d71edbf 100644 (file)
--- a/Lib/test/test_userdict.py
+++ b/Lib/test/test_userdict.py
@@ -75,6 +75,10 @@ m2 = MyUserDict(u2)
 m2a = m2.copy()
 verify(m2a == m2)
 
+# SF bug #476616 -- copy() of UserDict subclass shared data
+m2['foo'] = 'bar'
+verify(m2a != m2)
+
 # Test keys, items, values
 
 verify(u2.keys() == d2.keys())