diff --git a/Lib/test/list_tests.py b/Lib/test/list_tests.py index 1adfc75b77a0..f20fdc0a5f0a 100644 --- a/Lib/test/list_tests.py +++ b/Lib/test/list_tests.py @@ -593,3 +593,14 @@ class F(object): 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 --git a/Lib/test/test_bytes.py b/Lib/test/test_bytes.py index 90bcc42dbd8d..69e5bc99522e 100644 --- a/Lib/test/test_bytes.py +++ b/Lib/test/test_bytes.py @@ -17,6 +17,7 @@ import test.support import test.string_tests import test.buffer_tests +import test.list_tests from test.support import bigaddrspacetest, MAX_Py_ssize_t @@ -1418,6 +1419,7 @@ def test_iterator_pickling2(self): b[:] = data self.assertEqual(list(it), []) + test_exhausted_iterator = test.list_tests.CommonTest.test_exhausted_iterator class AssortedBytesTest(unittest.TestCase): # diff --git a/Lib/test/test_iter.py b/Lib/test/test_iter.py index 54ddbaa5fdf4..a91670b4a11f 100644 --- a/Lib/test/test_iter.py +++ b/Lib/test/test_iter.py @@ -190,6 +190,17 @@ def test_mutating_seq_class_iter_pickle(self): self.assertTrue(isinstance(it, collections.abc.Iterator)) self.assertEqual(list(it), []) + 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):