Class ExceptionInfo

src/_pytest/_code/code.py:446–680

Wraps sys.exc_info() objects and offers help for navigating the traceback.

@final
@attr.s(repr=False, init=False, auto_attribs=True)
class ExceptionInfo(Generic[E]):
    """Wraps sys.exc_info() objects and offers help for navigating the traceback."""

    _assert_start_repr: ClassVar = "AssertionError('assert "

    _excinfo: Optional[Tuple[Type["E"], "E", TracebackType]]
    _striptext: str
    _traceback: Optional[Traceback]

    def __init__(
        self,
        excinfo: Optional[Tuple[Type["E"], "E", TracebackType]],
        striptext: str = "",
        traceback: Optional[Traceback] = None,
        *,
        _ispytest: bool = False,
    ) -> None:
        check_ispytest(_ispytest)
        self._excinfo = excinfo
        self._striptext = striptext
        self._traceback = traceback

    @classmethod
    def from_exc_info(
        cls,
        exc_info: Tuple[Type[E], E, TracebackType],
        exprinfo: Optional[str] = None,
    ) -> "ExceptionInfo[E]":
        """Return an ExceptionInfo for an existing exc_info tuple.

        .. warning::

            Experimental API

        :param exprinfo:
            A text string helping to determine if we should strip
            ``AssertionError`` from the output. Defaults to the exception
            message/``__str__()``.
        """
        _striptext = ""
        if exprinfo is None and isinstance(exc_info[1], AssertionError):
            exprinfo = getattr(exc_info[1], "msg", None)
            if exprinfo is None:
                exprinfo = saferepr(exc_info[1])
            if exprinfo and exprinfo.startswith(cls._assert_start_repr):
                _striptext = "AssertionError: "

        return cls(exc_info, _striptext, _ispytest=True)

    @classmethod
    def from_current(
        cls, exprinfo: Optional[str] = None
    ) -> "ExceptionInfo[BaseException]":
        """Return an ExceptionInfo matching the current traceback.

        .. warning::

            Experimental API