[AlexXuz]

What Is This?

Preserve asynchronous handler errors regardless of their truthiness by checking the None sentinel returned by Future.exception() directly.

Add regression tests for both coroutine handlers and returned futures, covering exception types whose __bool__ returns False or raises. The tests assert that the original exception object reaches the error listener.

Why Is This?

The asyncio completion callback currently uses if exc. An exception with __bool__ returning False is silently discarded instead of reaching the error listener. If __bool__ raises, the callback fails with that new error instead.

Using if exc is not None preserves the original exception object without evaluating its truth value. Successful and cancelled futures keep their existing behavior.

Anything We Need To Know?

AI coding assistants were used for this contribution, including the implementation and independent review. The commit subject and upcoming changelog entry use the required 🤖 marker. Added the public GitHub handle to CONTRIBUTORS.md without an email address.

Validation:

• All four new regression cases fail on the original source.
• Linux CPython 3.12.14 and 3.13.5: all 57 tests pass on each.
• Black, isort, flake8, mypy (16 files), Pyright and project metadata validation pass.
• An independent local 79-case matrix passed, covering synchronous/coroutine/Task/Future handlers, error listeners, success and cancellation. The unmodified baseline failed 36 affected cases.
• Python 3.14, other operating systems, documentation builds and distribution builds were not tested locally.

Questions

• Has the developer read DEVELOPMENT.md?
• Have tests been updated accordingly?
• Have AI assisted commits been marked with a 🤖 emoji?
• Have AI assisted changes been marked with a 🤖 emoji in CHANGELOG.md?
• Does the PR notify the use of AI coding assistants?
• Is the developer's name in the CONTRIBUTORS.md file?