changeset:   100805:249ef9d02aa6
branch:      2.7
parent:      100802:cff06d875678
user:        Serhiy Storchaka <storchaka@gmail.com>
date:        Wed Mar 30 21:02:00 2016 +0300
files:       Lib/test/list_tests.py Lib/test/test_bytes.py Lib/test/test_iter.py
description:
Issue #26492: Added additional tests for exhausted iterators of mutable sequences.


diff -r cff06d875678 -r 249ef9d02aa6 Lib/test/list_tests.py
--- a/Lib/test/list_tests.py	Wed Mar 30 20:43:06 2016 +0300
+++ b/Lib/test/list_tests.py	Wed Mar 30 21:02:00 2016 +0300
@@ -532,3 +532,14 @@
             def __iter__(self):
                 raise KeyboardInterrupt
         self.assertRaises(KeyboardInterrupt, list, F())
+
+    def test_exhausted_iterator(self):
+        a = self.type2test([1, 2, 3])
+        exhit = iter(a)
+        empit = iter(a)
+        for x in exhit:  # exhaust the iterator
+            next(empit)  # not exhausted
+        a.append(9)
+        self.assertEqual(list(exhit), [])
+        self.assertEqual(list(empit), [9])
+        self.assertEqual(a, self.type2test([1, 2, 3, 9]))
diff -r cff06d875678 -r 249ef9d02aa6 Lib/test/test_bytes.py
--- a/Lib/test/test_bytes.py	Wed Mar 30 20:43:06 2016 +0300
+++ b/Lib/test/test_bytes.py	Wed Mar 30 21:02:00 2016 +0300
@@ -900,6 +900,16 @@
         # PyByteArray_AS_STRING() C macro.
         self.assertRaises(ValueError, int, bytearray(b''))
 
+    def test_exhausted_iterator(self):
+        a = self.type2test([1, 2, 3])
+        exhit = iter(a)
+        empit = iter(a)
+        for x in exhit:  # exhaust the iterator
+            next(empit)  # not exhausted
+        a.append(9)
+        self.assertEqual(list(exhit), [])
+        self.assertEqual(list(empit), [9])
+        self.assertEqual(a, self.type2test([1, 2, 3, 9]))
 
 class AssortedBytesTest(unittest.TestCase):
     #
diff -r cff06d875678 -r 249ef9d02aa6 Lib/test/test_iter.py
--- a/Lib/test/test_iter.py	Wed Mar 30 20:43:06 2016 +0300
+++ b/Lib/test/test_iter.py	Wed Mar 30 21:02:00 2016 +0300
@@ -122,6 +122,17 @@
     def test_seq_class_iter(self):
         self.check_iterator(iter(SequenceClass(10)), range(10))
 
+    def test_mutating_seq_class_exhausted_iter(self):
+        a = SequenceClass(5)
+        exhit = iter(a)
+        empit = iter(a)
+        for x in exhit:  # exhaust the iterator
+            next(empit)  # not exhausted
+        a.n = 7
+        self.assertEqual(list(exhit), [])
+        self.assertEqual(list(empit), [5, 6])
+        self.assertEqual(list(a), [0, 1, 2, 3, 4, 5, 6])
+
     # Test a new_style class with __iter__ but no next() method
     def test_new_style_iter_class(self):
         class IterClass(object):