bpo-34610: Fixed iterator of multiprocessing.managers.DictProxy. (GH-9113)

(cherry picked from commit e0e5065daef36dafe10a46eaa8b7800274d73062)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/Lib/test/_test_multiprocessing.py b/Lib/test/_test_multiprocessing.py
index 5c625dd495..9d4917076c 100644
--- a/Lib/test/_test_multiprocessing.py
+++ b/Lib/test/_test_multiprocessing.py
@@ -1813,6 +1813,16 @@ class _TestContainers(BaseTestCase):
         a.append('hello')
         self.assertEqual(f[0][:], [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 'hello'])
 
+    def test_list_iter(self):
+        a = self.list(list(range(10)))
+        it = iter(a)
+        self.assertEqual(list(it), list(range(10)))
+        self.assertEqual(list(it), [])  # exhausted
+        # list modified during iteration
+        it = iter(a)
+        a[0] = 100
+        self.assertEqual(next(it), 100)
+
     def test_list_proxy_in_list(self):
         a = self.list([self.list(range(3)) for _i in range(3)])
         self.assertEqual([inner[:] for inner in a], [[0, 1, 2]] * 3)
@@ -1843,6 +1853,19 @@ class _TestContainers(BaseTestCase):
         self.assertEqual(sorted(d.values()), [chr(i) for i in indices])
         self.assertEqual(sorted(d.items()), [(i, chr(i)) for i in indices])
 
+    def test_dict_iter(self):
+        d = self.dict()
+        indices = list(range(65, 70))
+        for i in indices:
+            d[i] = chr(i)
+        it = iter(d)
+        self.assertEqual(list(it), indices)
+        self.assertEqual(list(it), [])  # exhausted
+        # dictionary changed size during iteration
+        it = iter(d)
+        d.clear()
+        self.assertRaises(RuntimeError, next, it)
+
     def test_dict_proxy_nested(self):
         pets = self.dict(ferrets=2, hamsters=4)
         supplies = self.dict(water=10, feed=3)