Issue #23293, asyncio: Rewrite IocpProactor.connect_pipe() as a coroutine

Use a coroutine with asyncio.sleep() instead of call_later() to ensure that the
schedule call is cancelled.

Add also a unit test cancelling connect_pipe().

1 files changed, 13 insertions, 0 deletions

diff --git a/Lib/test/test_asyncio/test_windows_events.py b/Lib/test/test_asyncio/test_windows_events.py
index f9b3dd1..73d8fcd 100644
--- a/Lib/test/test_asyncio/test_windows_events.py
+++ b/Lib/test/test_asyncio/test_windows_events.py
@@ -1,6 +1,7 @@
 import os
 import sys
 import unittest
+from unittest import mock
 
 if sys.platform != 'win32':
     raise unittest.SkipTest('Windows only')
@@ -91,6 +92,18 @@ class ProactorTests(test_utils.TestCase):
 
         return 'done'
 
+    def test_connect_pipe_cancel(self):
+        exc = OSError()
+        exc.winerror = _overlapped.ERROR_PIPE_BUSY
+        with mock.patch.object(_overlapped, 'ConnectPipe', side_effect=exc) as connect:
+            coro = self.loop._proactor.connect_pipe('pipe_address')
+            task = self.loop.create_task(coro)
+
+            # check that it's possible to cancel connect_pipe()
+            task.cancel()
+            with self.assertRaises(asyncio.CancelledError):
+                self.loop.run_until_complete(task)
+
     def test_wait_for_handle(self):
         event = _overlapped.CreateEvent(None, True, False, None)
         self.addCleanup(_winapi.CloseHandle, event)