Class RaisesGroup

src/_pytest/raises.py:724–1444

.. versionadded:: 8.4 Contextmanager for checking for an expected :exc:`ExceptionGroup`. This works similar to :func:`pytest.raises`, but allows for specifying the structure of an :exc:`ExceptionGroup`. :meth:`ExceptionInfo.group_contains` also tries to handle exception groups,

@final
class RaisesGroup(AbstractRaises[BaseExceptionGroup[BaseExcT_co]]):
    """
    .. versionadded:: 8.4

    Contextmanager for checking for an expected :exc:`ExceptionGroup`.
    This works similar to :func:`pytest.raises`, but allows for specifying the structure of an :exc:`ExceptionGroup`.
    :meth:`ExceptionInfo.group_contains` also tries to handle exception groups,
    but it is very bad at checking that you *didn't* get unexpected exceptions.

    The catching behaviour differs from :ref:`except* <except_star>`, being much
    stricter about the structure by default.
    By using ``allow_unwrapped=True`` and ``flatten_subgroups=True`` you can match
    :ref:`except* <except_star>` fully when expecting a single exception.

    :param args:
        Any number of exception types, :class:`RaisesGroup` or :class:`RaisesExc`
        to specify the exceptions contained in this exception.
        All specified exceptions must be present in the raised group, *and no others*.

        If you expect a variable number of exceptions you need to use
        :func:`pytest.raises(ExceptionGroup) <pytest.raises>` and manually check
        the contained exceptions. Consider making use of :meth:`RaisesExc.matches`.

        It does not care about the order of the exceptions, so
        ``RaisesGroup(ValueError, TypeError)``
        is equivalent to
        ``RaisesGroup(TypeError, ValueError)``.
    :kwparam str | re.Pattern[str] | None match:
        If specified, a string containing a regular expression,
        or a regular expression object, that is tested against the string
        representation of the exception group and its :pep:`678` `__notes__`
        using :func:`re.search`.

        To match a literal string that may contain :ref:`special characters
        <re-syntax>`, the pattern can first be escaped with :func:`re.escape`.

        Note that " (5 subgroups)" will be stripped from the ``repr`` before matching.
    :kwparam Callable[[E], bool] check:
        If specified, a callable that will be called with the group as a parameter
        after successfully matching the expected exceptions. If it returns ``True``
        it will be considered a match, if not it will be considered a failed match.
    :kwparam bool allow_unwrapped:
        If expecting a single exception or :class:`RaisesExc` it will match even
        if the exception is not inside an exceptiongroup.

        Using this together with ``match``, ``check`` or expecting multiple exceptions
        will raise an error.
    :kwparam bool flatten_subgroups:
        "flatten" any groups inside the raised exception group, extracting all exceptions
        inside any nested groups, before matching. Without this it expects you to
        fully specify the nesting structure by passing :class:`RaisesGroup` as expected
        parameter.

    Examples::

        with RaisesGroup(ValueError):
            raise ExceptionGroup("", (ValueError(),))
        # match