GH-94597: Deprecate child watcher getters and setters (#98215)

This is the next step for deprecating child watchers.

Until we've removed the API completely we have to use it, so this PR is mostly suppressing a lot of warnings when using the API internally.

Once the child watcher API is totally removed, the two child watcher implementations we actually use and need (Pidfd and Thread) will be turned into internal helpers.

1 files changed, 12 insertions, 9 deletions

diff --git a/Lib/test/test_asyncio/test_unix_events.py b/Lib/test/test_asyncio/test_unix_events.py
index 025da0f..d806ed4 100644
--- a/Lib/test/test_asyncio/test_unix_events.py
+++ b/Lib/test/test_asyncio/test_unix_events.py
@@ -1709,33 +1709,36 @@ class PolicyTests(unittest.TestCase):
         self.assertIsNone(policy._watcher)
         unix_events.can_use_pidfd = mock.Mock()
         unix_events.can_use_pidfd.return_value = False
-        watcher = policy.get_child_watcher()
+        with self.assertWarns(DeprecationWarning):
+            watcher = policy.get_child_watcher()
         self.assertIsInstance(watcher, asyncio.ThreadedChildWatcher)
 
         self.assertIs(policy._watcher, watcher)
-
-        self.assertIs(watcher, policy.get_child_watcher())
+        with self.assertWarns(DeprecationWarning):
+            self.assertIs(watcher, policy.get_child_watcher())
 
         policy = self.create_policy()
         self.assertIsNone(policy._watcher)
         unix_events.can_use_pidfd = mock.Mock()
         unix_events.can_use_pidfd.return_value = True
-        watcher = policy.get_child_watcher()
+        with self.assertWarns(DeprecationWarning):
+            watcher = policy.get_child_watcher()
         self.assertIsInstance(watcher, asyncio.PidfdChildWatcher)
 
         self.assertIs(policy._watcher, watcher)
-
-        self.assertIs(watcher, policy.get_child_watcher())
+        with self.assertWarns(DeprecationWarning):
+            self.assertIs(watcher, policy.get_child_watcher())
 
     def test_get_child_watcher_after_set(self):
         policy = self.create_policy()
         with warnings.catch_warnings():
             warnings.simplefilter("ignore", DeprecationWarning)
             watcher = asyncio.FastChildWatcher()
+            policy.set_child_watcher(watcher)
 
-        policy.set_child_watcher(watcher)
         self.assertIs(policy._watcher, watcher)
-        self.assertIs(watcher, policy.get_child_watcher())
+        with self.assertWarns(DeprecationWarning):
+            self.assertIs(watcher, policy.get_child_watcher())
 
     def test_get_child_watcher_thread(self):
 
@@ -1769,7 +1772,7 @@ class PolicyTests(unittest.TestCase):
         with warnings.catch_warnings():
             warnings.simplefilter("ignore", DeprecationWarning)
             watcher = asyncio.SafeChildWatcher()
-        policy.set_child_watcher(watcher)
+            policy.set_child_watcher(watcher)
         watcher.attach_loop(loop)
 
         self.assertIs(watcher._loop, loop)