Function fail_callback

tests/test_fork_backends.py:466–467

(_fd: int)

    callback_error.__context__ = prior_context

    def fail_callback(_fd: int) -> None:
        raise callback_error

    lock = _CoroutineDescriptorLock(
        str(tmp_path / "coroutine-hook-context.lock"), is_singleton=False, on_acquired=fail_callback