From 932611bb1fd27a016521623e4f049e41d406d3c9 Mon Sep 17 00:00:00 2001
From: Andreas Schneider <asn@cryptomilk.org>
Date: Fri, 3 Jan 2025 08:37:22 +0100
Subject: [PATCH] Replace deprecated asyncio.get_child_watcher()

Use PidfdChildWatcher if os.pidfd_open is available and
otherwise use ThreadedChildWatcher which should work in any case.

Fixes #583
---
 pynvim/msgpack_rpc/event_loop/asyncio.py | 41 +++++++++++++++++++++---
 1 file changed, 37 insertions(+), 4 deletions(-)

diff --git a/pynvim/msgpack_rpc/event_loop/asyncio.py b/pynvim/msgpack_rpc/event_loop/asyncio.py
index cb17f321..5d8ef2a0 100644
--- a/pynvim/msgpack_rpc/event_loop/asyncio.py
+++ b/pynvim/msgpack_rpc/event_loop/asyncio.py
@@ -188,10 +188,42 @@ async def connect_stdout():
 
     @override
     def _connect_child(self, argv: List[str]) -> None:
+        def can_use_pidfd():
+            # Unix system without pidfd_open?
+            if not hasattr(os, 'pidfd_open'):
+                return False
+
+            # Check that we are not blocked by security policy like SECCOMP
+            try:
+                pid = os.getpid()
+                fd = os.pidfd_open(pid, 0)
+                os.close(fd)
+            except OSError:
+                return False
+
+            return True
+
+        def get_child_watcher():
+            if can_use_pidfd():
+                try:
+                    from asyncio.unix_events import PidfdChildWatcher
+                    return PidfdChildWatcher()
+                except ImportError:
+                    pass
+
+            try:
+                from asyncio.unix_events import ThreadedChildWatcher
+                return ThreadedChildWatcher()
+            except ImportError:
+                pass
+
+            # FIXME Python 3.7, return None if we drop support
+            return asyncio.get_child_watcher()
+
         if os.name != 'nt':
-            # see #238, #241
-            self._child_watcher = asyncio.get_child_watcher()
-            self._child_watcher.attach_loop(self._loop)
+            watcher = get_child_watcher()
+            watcher.attach_loop(self._loop)
+            self._child_watcher = watcher
 
         async def create_subprocess():
             transport: asyncio.SubprocessTransport  # type: ignore
@@ -250,7 +282,8 @@ def _close_transport(transport):
             # Windows: for ProactorBasePipeTransport, close() doesn't take in
             # effect immediately (closing happens asynchronously inside the
             # event loop), need to wait a bit for completing graceful shutdown.
-            if os.name == 'nt' and hasattr(transport, '_sock'):
+            if (sys.version_info.major == 3 and sys.version_info.minor < 13 and
+                    os.name == 'nt' and hasattr(transport, '_sock')):
                 async def wait_until_closed():
                     # pylint: disable-next=protected-access
                     while transport._sock is not None: