🐛 Fix syncify with raise_sync_error=False on AnyIO 4.x.x, do not start new event loops unnecessarily
Currently, when using syncify(do_stuff, raise_sync_error=False)() and AnyIO 4.x.x, when running on an async context (there is a parent main async function, e.g. with FastAPI), it will instead of sending the async task to the async event loop in the main thread as it should, it will start a new event loop for this async task, which is incorrect behavior when there's a parent async function, it's the correct behavior only when there's no async parent function.
This is because AnyIO 4.x.x changed the internal name current_async_module with current_async_backend and Asyncer was only checking for that.
This includes the fix and tests that verify that jumping from async to sync to async and all those possible async sandwiches behave correctly, running things in the correct thread (the main thread with the event loop or worker threads for sync functions under async parents).
🐛 Fix
syncifywithraise_sync_error=Falseon AnyIO 4.x.x, do not start new event loops unnecessarilyCurrently, when using
syncify(do_stuff, raise_sync_error=False)()and AnyIO 4.x.x, when running on an async context (there is a parent main async function, e.g. with FastAPI), it will instead of sending the async task to the async event loop in the main thread as it should, it will start a new event loop for this async task, which is incorrect behavior when there's a parent async function, it's the correct behavior only when there's no async parent function.This is because AnyIO 4.x.x changed the internal name
current_async_modulewithcurrent_async_backendand Asyncer was only checking for that.This includes the fix and tests that verify that jumping from async to sync to async and all those possible async sandwiches behave correctly, running things in the correct thread (the main thread with the event loop or worker threads for sync functions under async parents).