Python issue #23243: On Python 3.4 and newer, emit a ResourceWarning when anHEADmaster

event loop or a transport is not explicitly closed

1 files changed, 5 insertions, 1 deletions

diff --git a/asyncio/windows_utils.py b/asyncio/windows_utils.py
index 5f8327e..870cd13 100644
--- a/asyncio/windows_utils.py
+++ b/asyncio/windows_utils.py
@@ -14,6 +14,7 @@ import os
 import socket
 import subprocess
 import tempfile
+import warnings
 
 
 __all__ = ['socketpair', 'pipe', 'Popen', 'PIPE', 'PipeHandle']
@@ -156,7 +157,10 @@ class PipeHandle:
             CloseHandle(self._handle)
             self._handle = None
 
-    __del__ = close
+    def __del__(self):
+        if self._handle is not None:
+            warnings.warn("unclosed %r" % self, ResourceWarning)
+            self.close()
 
     def __enter__(self):
         return self