[3.11] gh-100931: Test all `pickle` protocols in `test_slice` (GH-100932). (GH-100979)

(cherry picked from commit 8795ad1bd0d6ee031543fcaf5a86a60b37950714)

Co-authored-by: Nikita Sobolev <mail@sobolevn.me>
Automerge-Triggered-By: GH:AlexWaygood

diff --git a/Lib/test/test_slice.py b/Lib/test/test_slice.py
index 584e5c7f17c2f6dd6a7bbf7ed5b104697476b629..03fde3275e1475dc6467cf78270d9102c55da9bd 100644 (file)
--- a/Lib/test/test_slice.py
+++ b/Lib/test/test_slice.py
@@ -236,8 +236,10 @@ class SliceTest(unittest.TestCase):
         self.assertEqual(tmp, [(slice(1, 2), 42)])
 
     def test_pickle(self):
+        import pickle
+
         s = slice(10, 20, 3)
-        for protocol in (0,1,2):
+        for protocol in range(pickle.HIGHEST_PROTOCOL + 1):
             t = loads(dumps(s, protocol))
             self.assertEqual(s, t)
             self.assertEqual(s.indices(15), t.indices(15))