Method make_dual_exception_instance

python/ray/exceptions.py:161–173

Makes a object instance that inherits from both RayTaskError and the type of `self.cause`. Raises TypeError if the cause class can't be subclassed

(self)

        assert traceback_str is not None

    def make_dual_exception_instance(self) -> "RayTaskError":
        """Makes a object instance that inherits from both RayTaskError and the type of
        `self.cause`. Raises TypeError if the cause class can't be subclassed"""
        # For normal user Exceptions, we subclass from both
        # RayTaskError and the user exception. For ExceptionGroup,
        # we special handle it because it has a different __new__()
        # signature from Exception.
        # Ref: https://docs.python.org/3/library/exceptions.html#exception-groups
        if sys.version_info >= (3, 11) and isinstance(
            self.cause, ExceptionGroup  # noqa: F821
        ):
            return self._make_exceptiongroup_dual_exception_instance()
        return self._make_normal_dual_exception_instance()

    def _make_normal_dual_exception_instance(self) -> "RayTaskError":
        cause_cls = self.cause.__class__