Issue #14288: Serialization support for builtin iterators.

Lib/test/test_enumerate.py

@@ -1,5 +1,6 @@
 import unittest
 import sys
+import pickle
 
 from test import support
 
@@ -61,7 +62,25 @@ class N:
     def __iter__(self):
         return self
 
-class EnumerateTestCase(unittest.TestCase):
+class PickleTest:
+    # Helper to check picklability
+    def check_pickle(self, itorg, seq):
+        d = pickle.dumps(itorg)
+        it = pickle.loads(d)
+        self.assertEqual(type(itorg), type(it))
+        self.assertEqual(list(it), seq)
+
+        it = pickle.loads(d)
+        try:
+            next(it)
+        except StopIteration:
+            self.assertFalse(seq[1:])
+            return
+        d = pickle.dumps(it)
+        it = pickle.loads(d)
+        self.assertEqual(list(it), seq[1:])
+
+class EnumerateTestCase(unittest.TestCase, PickleTest):
 
     enum = enumerate
     seq, res = 'abc', [(0,'a'), (1,'b'), (2,'c')]
@@ -73,6 +92,9 @@ class EnumerateTestCase(unittest.TestCase):
         self.assertEqual(list(self.enum(self.seq)), self.res)
         self.enum.__doc__
 
+    def test_pickle(self):
+        self.check_pickle(self.enum(self.seq), self.res)
+
     def test_getitemseqn(self):
         self.assertEqual(list(self.enum(G(self.seq))), self.res)
         e = self.enum(G(''))
@@ -126,7 +148,7 @@ class TestBig(EnumerateTestCase):
     seq = range(10,20000,2)
     res = list(zip(range(20000), seq))
 
-class TestReversed(unittest.TestCase):
+class TestReversed(unittest.TestCase, PickleTest):
 
     def test_simple(self):
         class A:
@@ -212,6 +234,10 @@ class TestReversed(unittest.TestCase):
         ngi = NoGetItem()
         self.assertRaises(TypeError, reversed, ngi)
 
+    def test_pickle(self):
+        for data in 'abc', range(5), tuple(enumerate('abc')), range(1,17,5):
+            self.check_pickle(reversed(data), list(data)[::-1])
+
 
 class EnumerateStartTestCase(EnumerateTestCase):