concurrent.futures.Future.add_done_callback: calling thread description error.

asyncio.run_coroutine_threadsafe will return a concurrent.futures.Future.
And according to its doc concurrent.futures.Future.add_done_callback() :

Added callables are called in the order that they were added and are always ** called in a thread belonging to the process that added them. **

But acually, the callback is called in where Future.set_result() is called according to its source.

Linked PRs

• gh-122678

concurrent.futures.Future.add_done_callback() のドキュメントと、asyncio.run_coroutine_threadsafe を介して到達する動作から始め、Future.set_result() のソースパスと記述を比較します。変更を加える前に既存のリンクされた PR を考慮したうえで、コールバックが実行されるスレッドをドキュメントが正確に説明していれば完了です。