commit 9128732de668e5777e135a423d3fa8b9bbd71fe1
author Daniel Stutzbach <daniel@stutzbachenterprises.com> Tue Aug 24 21:09:30 2010 +0000
committer Daniel Stutzbach <daniel@stutzbachenterprises.com> Tue Aug 24 21:09:30 2010 +0000
tree 19cf1f302337c077e6a421d247fedfd2f7f907dd
parent 6fb0fd12328449d7899f11d42f11e2b0d39231cf

Merged revisions 84301 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k

........
  r84301 | daniel.stutzbach | 2010-08-24 15:49:57 -0500 (Tue, 24 Aug 2010) | 1 line

  Issue 8750: Fixed MutableSet's methods to correctly handle reflexive operations, namely x -= x and x ^= x
........

Lib/test/test_collections.py

diff --git a/Lib/test/test_collections.py b/Lib/test/test_collections.py
index f10f956..16c4552 100644
--- a/Lib/test/test_collections.py
+++ b/Lib/test/test_collections.py
@@ -526,6 +526,21 @@
         s = MySet([5,43,2,1])
         self.assertEqual(s.pop(), 1)
 
+    def test_issue8750(self):
+        empty = WithSet()
+        full = WithSet(range(10))
+        s = WithSet(full)
+        s -= s
+        self.assertEqual(s, empty)
+        s = WithSet(full)
+        s ^= s
+        self.assertEqual(s, empty)
+        s = WithSet(full)
+        s &= s
+        self.assertEqual(s, full)
+        s |= s
+        self.assertEqual(s, full)
+
     def test_Mapping(self):
         for sample in [dict]:
             self.assertIsInstance(sample(), Mapping)