Class _SlowRollbackCon

tests/test_read_write_unit.py:592–599

    real_con = lock._con

    class _SlowRollbackCon:
        def rollback(self) -> None:  # noqa: PLR6301
            started.set()
            proceed.wait(timeout=5)
            real_con.rollback()

        def __getattr__(self, name: str) -> object:
            return getattr(real_con, name)

    lock._con = _SlowRollbackCon()  # ty: ignore[invalid-assignment]
    threading.Thread(target=lock.release, daemon=True).start()