gh-124245: Fix UserWarning in test_argparse (GH-124246)

diff --git a/Lib/test/test_argparse.py b/Lib/test/test_argparse.py
index 584462b741ee9965b2343bc551f676408e4b1da9..435db65d52fddb1124b48550667e61f6d0106190 100644 (file)
--- a/Lib/test/test_argparse.py
+++ b/Lib/test/test_argparse.py
@@ -5811,9 +5811,8 @@ class TestIntermixedArgs(TestCase):
         parser = ErrorRaisingArgumentParser(prog='PROG')
         parser.add_argument('--foo', nargs="*")
         parser.add_argument('foo')
-        with captured_stderr() as stderr:
+        with self.assertWarns(UserWarning):
             parser.parse_intermixed_args(['hello', '--foo'])
-            self.assertIn("UserWarning", stderr.getvalue())
 
 class TestIntermixedMessageContentError(TestCase):
     # case where Intermixed gives different error message