[fantix]

Don't passthrough task local to spawned tasks which are not immediately joined.

@AmatanHead please review if this works for #84

[AmatanHead]

This looks nice. However, what happens if one call .add_done_callback() manually? In this case, task locals would be inherited from wherever .add_done_callback() was called. For example:

...
# We generally don't want to inherit task locals here
asyncio.ensure_future(coro()).add_done_callback(callback)
...

Right now, I see no way to detect such cases. Also, such behaviour makes the whole mechanism even more implicit and unpredictable. So I think, maybe I was too hastened to open #84... Maybe we should just state that task locals inherit from wherever the task was created unless drop_locals() is used?

Also, it would be nice to have a way to check if task locals are enabled ant not inherited. Right now, I use something like assert get_local() is not None. An additional task_local_is_not_inherited assertion can prevent a lot of unexpected things.

[fantix]

Yeah I was thinking about temporarily store the context at spawning, and only set it active on add_done_callback instead of get context in the callback, still the issue would be the same - manually adding done callbacks are considered "joining" when it is probably not. I'll update this PR.

[AmatanHead]

what about

just state that task locals inherit from wherever the task was created unless drop_locals() is used?

Is it an option?

[fantix]

Yes definitely! Please see update.

[AmatanHead]

This is great!

[fantix]

Thx for reviewing and commenting. I'll merge this first and start a new issue for renaming/new package issue, because #84 was actually about managing the inherit behavior but not renaming.