1 files changed, 82 insertions, 1 deletions
diff --git a/Lib/test/test_dict.py b/Lib/test/test_dict.py
index d2740a3384..b43e20d055 100644
--- a/Lib/test/test_dict.py
+++ b/Lib/test/test_dict.py
@@ -2,7 +2,9 @@ import unittest
 from test import support
 
 import collections, random, string
+import collections.abc
 import gc, weakref
+import pickle
 
 
 class DictTest(unittest.TestCase):
@@ -379,7 +381,7 @@ class DictTest(unittest.TestCase):
         x.fail = True
         self.assertRaises(Exc, d.pop, x)
 
-    def test_mutatingiteration(self):
+    def test_mutating_iteration(self):
         # changing dict size during iteration
         d = {}
         d[1] = 1
@@ -387,6 +389,33 @@ class DictTest(unittest.TestCase):
             for i in d:
                 d[i+1] = 1
 
+    def test_mutating_lookup(self):
+        # changing dict during a lookup
+        class NastyKey:
+            mutate_dict = None
+
+            def __init__(self, value):
+                self.value = value
+
+            def __hash__(self):
+                # hash collision!
+                return 1
+
+            def __eq__(self, other):
+                if NastyKey.mutate_dict:
+                    mydict, key = NastyKey.mutate_dict
+                    NastyKey.mutate_dict = None
+                    del mydict[key]
+                return self.value == other.value
+
+        key1 = NastyKey(1)
+        key2 = NastyKey(2)
+        d = {key1: 1}
+        NastyKey.mutate_dict = (d, key1)
+        with self.assertRaisesRegex(RuntimeError,
+                                    'dictionary changed size during lookup'):
+            d[key2] = 2
+
     def test_repr(self):
         d = {}
         self.assertEqual(repr(d), '{}')
@@ -776,6 +805,58 @@ class DictTest(unittest.TestCase):
             pass
         self._tracked(MyDict())
 
+    def test_iterator_pickling(self):
+        data = {1:"a", 2:"b", 3:"c"}
+        it = iter(data)
+        d = pickle.dumps(it)
+        it = pickle.loads(d)
+        self.assertEqual(sorted(it), sorted(data))
+
+        it = pickle.loads(d)
+        try:
+            drop = next(it)
+        except StopIteration:
+            return
+        d = pickle.dumps(it)
+        it = pickle.loads(d)
+        del data[drop]
+        self.assertEqual(sorted(it), sorted(data))
+
+    def test_itemiterator_pickling(self):
+        data = {1:"a", 2:"b", 3:"c"}
+        # dictviews aren't picklable, only their iterators
+        itorg = iter(data.items())
+        d = pickle.dumps(itorg)
+        it = pickle.loads(d)
+        # note that the type of type of the unpickled iterator
+        # is not necessarily the same as the original.  It is
+        # merely an object supporting the iterator protocol, yielding
+        # the same objects as the original one.
+        # self.assertEqual(type(itorg), type(it))
+        self.assertTrue(isinstance(it, collections.abc.Iterator))
+        self.assertEqual(dict(it), data)
+
+        it = pickle.loads(d)
+        drop = next(it)
+        d = pickle.dumps(it)
+        it = pickle.loads(d)
+        del data[drop[0]]
+        self.assertEqual(dict(it), data)
+
+    def test_valuesiterator_pickling(self):
+        data = {1:"a", 2:"b", 3:"c"}
+        # data.values() isn't picklable, only its iterator
+        it = iter(data.values())
+        d = pickle.dumps(it)
+        it = pickle.loads(d)
+        self.assertEqual(sorted(list(it)), sorted(list(data.values())))
+
+        it = pickle.loads(d)
+        drop = next(it)
+        d = pickle.dumps(it)
+        it = pickle.loads(d)
+        values = list(it) + [drop]
+        self.assertEqual(sorted(values), sorted(list(data.values())))
 
 from test import mapping_tests