gh-106503: asyncio._SelectorSocketTransport: fix cyclic reference on close(). (#106504)

Lib/asyncio/selector_events.py

@@ -1202,6 +1202,7 @@ class _SelectorSocketTransport(_SelectorTransport):
 
     def close(self):
         self._read_ready_cb = None
+        self._write_ready = None
         super().close()
 
 

Misc/ACKS

@@ -615,6 +615,7 @@ Marius Gedminas
 Jan-Philip Gehrcke
 Thomas Gellekum
 Gabriel Genellina
+Andrew Geng
 Philip Georgi
 Christos Georgiou
 Elazar (אלעזר) Gershuni

Misc/NEWS.d/next/Library/2023-07-07-03-05-58.gh-issue-106503.ltfeiH.rst

@@ -0,0 +1,2 @@
+Fix ref cycle in :class:`!asyncio._SelectorSocketTransport` by removing
+``_write_ready`` in ``close``.