Issue #24379: Add operator.subscript() as a convenience for building slices.
diff --git a/Lib/test/test_operator.py b/Lib/test/test_operator.py
index 54fd1f4..27501c2 100644
--- a/Lib/test/test_operator.py
+++ b/Lib/test/test_operator.py
@@ -596,5 +596,38 @@
module2 = c_operator
+class SubscriptTestCase:
+ def test_subscript(self):
+ subscript = self.module.subscript
+ self.assertIsNone(subscript[None])
+ self.assertEqual(subscript[0], 0)
+ self.assertEqual(subscript[0:1:2], slice(0, 1, 2))
+ self.assertEqual(
+ subscript[0, ..., :2, ...],
+ (0, Ellipsis, slice(2), Ellipsis),
+ )
+
+ def test_pickle(self):
+ from operator import subscript
+ for proto in range(pickle.HIGHEST_PROTOCOL + 1):
+ with self.subTest(proto=proto):
+ self.assertIs(
+ pickle.loads(pickle.dumps(subscript, proto)),
+ subscript,
+ )
+
+ def test_singleton(self):
+ with self.assertRaises(TypeError):
+ type(self.module.subscript)()
+
+ def test_immutable(self):
+ with self.assertRaises(AttributeError):
+ self.module.subscript.attr = None
+
+
+class PySubscriptTestCase(SubscriptTestCase, PyOperatorTestCase):
+ pass
+
+
if __name__ == "__main__":
unittest.main()