bpo-46829: Deprecate passing a message into Future.cancel() and Task.cancel() (GH-31840)

After a long deliberation we ended up feeling that the message argument for Future.cancel(), added in 3.9, was a bad idea, so we're deprecating it in 3.11 and plan to remove it in 3.13.

1 files changed, 10 insertions, 2 deletions

diff --git a/Lib/test/test_asyncio/test_futures.py b/Lib/test/test_asyncio/test_futures.py
index 84d7d45af94..cf677f6a951 100644
--- a/Lib/test/test_asyncio/test_futures.py
+++ b/Lib/test/test_asyncio/test_futures.py
@@ -228,14 +228,22 @@ class BaseFutureTests:
         self.assertTrue(hasattr(f, '_cancel_message'))
         self.assertEqual(f._cancel_message, None)
 
-        f.cancel('my message')
+        with self.assertWarnsRegex(
+            DeprecationWarning,
+            "Passing 'msg' argument"
+        ):
+            f.cancel('my message')
         with self.assertRaises(asyncio.CancelledError):
             self.loop.run_until_complete(f)
         self.assertEqual(f._cancel_message, 'my message')
 
     def test_future_cancel_message_setter(self):
         f = self._new_future(loop=self.loop)
-        f.cancel('my message')
+        with self.assertWarnsRegex(
+            DeprecationWarning,
+            "Passing 'msg' argument"
+        ):
+            f.cancel('my message')
         f._cancel_message = 'my new message'
         self.assertEqual(f._cancel_message, 'my new message')