fix(asyncify): avoid hanging process under certain conditions

[spokeydokeys]

• I understand that this repository is auto-generated and my pull request may not be merged

Changes being requested

This is a follow on PR for #1828 that updates the asyncify method to use asyncio.to_thread for python 3.9+ or a copy of the source code for the same for python 3.8. This was done since to_thread was only added to asyncio in python 3.9.

This addresses an issue where the code would hand with a left-over, non-daemon thread from anyio in certain contexts.

Additional context & links

#1827
#1828

[RobertCraigie]

Thanks! I assume getting a test setup for this would be difficult?

[spokeydokeys]

Thanks! I assume getting a test setup for this would be difficult?

I added a test that I can confirm fails on main, but works on the fixed branch.

I was concerned that since nest_asyncio.apply() is global and that I couldn't guarantee any particular test execution order, it might end up impacting other tests. For that reason I used a separate process and made sure that process closed in a timely manner. I used 2 seconds, which is quite long really, but the nature of the failure is that it hangs for much longer than that and I didn't want to introduce a flaky test if I cut the timeout too tight.

Let me know what you think.

[RobertCraigie]

looks like the test is failing is CI, I'm surprised there isn't any output from the subprocess? 🤔

[spokeydokeys]

looks like the test is failing is CI, I'm surprised there isn't any output from the subprocess? 🤔

I think it was because I foolishly added the nest_asyncio requirement to the lock file, rather than the pyproject.toml file so it was missing an import.

[RobertCraigie]

ahhh good catch, looks like it's not in the lock file anymore, you'll need to update it with rye sync

[spokeydokeys]

@RobertCraigie, rye sync done!

[spokeydokeys]

@RobertCraigie is there anything else that you need for this?

This fix enables us to run our automated AI tasks in github workflows and we are holding off on deploying until this is merged. I'm trying to gauge how much effort to put into workarounds based on timelines...

[RobertCraigie]

Thanks!