Issue 5794: fix cPickle's unpickling of recursive tuples.

2 files changed, 15 insertions, 0 deletions

diff --git a/Lib/test/pickletester.py b/Lib/test/pickletester.py
index bc0be1f845..ce49fdda78 100644
--- a/Lib/test/pickletester.py
+++ b/Lib/test/pickletester.py
@@ -463,6 +463,16 @@ class AbstractPickleTests(unittest.TestCase):
             self.assertEqual(len(x), 1)
             self.assert_(x is x[0])
 
+    def test_recursive_tuple(self):
+        t = ([],)
+        t[0].append(t)
+        for proto in protocols:
+            s = self.dumps(t, proto)
+            x = self.loads(s)
+            self.assertEqual(len(x), 1)
+            self.assertEqual(len(x[0]), 1)
+            self.assert_(x is x[0][0])
+
     def test_recursive_dict(self):
         d = {}
         d[1] = d
diff --git a/Lib/test/test_cpickle.py b/Lib/test/test_cpickle.py
index 054187313f..c240669873 100644
--- a/Lib/test/test_cpickle.py
+++ b/Lib/test/test_cpickle.py
@@ -65,6 +65,11 @@ class cPickleFastPicklerTests(AbstractPickleTests):
                           AbstractPickleTests.test_recursive_list,
                           self)
 
+    def test_recursive_tuple(self):
+        self.assertRaises(ValueError,
+                          AbstractPickleTests.test_recursive_tuple,
+                          self)
+
     def test_recursive_inst(self):
         self.assertRaises(ValueError,
                           AbstractPickleTests.test_recursive_inst,