asyncio: fix ResourceWarning related to subprocesses
Issue #26741: asyncio: BaseSubprocessTransport._process_exited() now copies the
return code from the child watched to the returncode attribute of the Popen
object. On Python 3.6, it is required to avoid a ResourceWarning.
diff --git a/Lib/asyncio/base_subprocess.py b/Lib/asyncio/base_subprocess.py
index 08080bd..8fc253c 100644
--- a/Lib/asyncio/base_subprocess.py
+++ b/Lib/asyncio/base_subprocess.py
@@ -210,6 +210,10 @@
logger.info('%r exited with return code %r',
self, returncode)
self._returncode = returncode
+ if self._proc.returncode is None:
+ # asyncio uses a child watcher: copy the status into the Popen
+ # object. On Python 3.6, it is required to avoid a ResourceWarning.
+ self._proc.returncode = returncode
self._call(self._protocol.process_exited)
self._try_finish()