On Python 3.13, "greenlet.error: cannot switch to a different thread" #425
Description
Eventlet runs on greenlet, but on Python 3.13rc2 tests that work on older versions of Python now fail (using this PR: eventlet/eventlet#966, and greenlet 3.1.0):
$ .tox/py313/bin/python tests/isolated/patcher_threading_join.py
Traceback (most recent call last):
File "/home/itamarst/devel/eventlet/eventlet/hubs/hub.py", line 471, in fire_timers
timer()
~~~~~^^
File "/home/itamarst/devel/eventlet/eventlet/hubs/timer.py", line 59, in __call__
cb(*args, **kw)
~~^^^^^^^^^^^^^
File "/home/itamarst/devel/eventlet/eventlet/semaphore.py", line 147, in _do_acquire
waiter.switch()
~~~~~~~~~~~~~^^
greenlet.error: cannot switch to a different thread
It's not clear if this is greenlet's fault or if eventlet is doing something wrong (but something wrong that used to work!). If you have any hints on how to debug this sort of problem that would be helpful in trying to fix it in eventlet.