Newest PyPy started failing

[A5rocks]

It looks like the v7.3.22 release of PyPy has made CI start to fail... I don't really get why at a glance and I don't have the time to dig deeper yet.

We should probably:

• diagnose the issue and report it to pypy (unless it's already been reported? it doesn't look like it has been reported yet.)
• hardcode the pypy version we test to 7.3.21 if possible, so that CI starts passing... or maybe the nightly version (if that's still a thing?) if the pypy fix comes fast enough?

[illia-v]

We see the error with the latest PyPy and Trio in urllib3's tests too
https://github.com/urllib3/urllib3/actions/runs/25104287021/job/73561383364

[A5rocks]

First pass:

import trio

async def blah():
    print("hello, world!")

trio.run(blah)

causing this:

/Users/a5rocks/Developer/trio/src/trio/_core/_run.py:2729: RuntimeWarning: coroutine 'Runner.init' was never awaited
  runner.init_task = runner.spawn_impl(
/Users/a5rocks/Developer/trio/src/trio/_core/_run.py:2157: RuntimeWarning: coroutine 'blah' was never awaited
  self.main_task = self.spawn_impl(
/Users/a5rocks/Developer/trio/src/trio/_core/_run.py:2166: RuntimeWarning: coroutine 'EntryQueue.task' was never awaited
  self.spawn_impl(
hello, world!

(at least I'm fairly certain that's the issue)

Also nightly doesn't seem to work either, so it hasn't been fixed yet.

[A5rocks]

Hm, it looks like this is due to pypy/pypy@79b7b09 (based on some basic grep + blame, I didn't bisect). Well, hopefully that gets reverted and fixed!

[A5rocks]

This is fixed in PyPy, let's leave this issue open until they release 7.3.23. People depending on Trio in CI should switch to either pypy-3.11-7.3.21 or pypy-3.11-nightly (actions/setup-python should support both), though note that the only nightly build w/ the fix ATM is linux.

Based on #3434 the only remaining issues (with -nightly) is that a) somehow astroid also doesn't support the latest pypy and b) that only linux has the new change.