########################################################################
# File name: utils.py
# This file is part of: aiosasl
#
# LICENSE
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this program.  If not, see
# <http://www.gnu.org/licenses/>.
#
########################################################################

import operator


def xor_bytes(a: bytes, b: bytes) -> bytes:
    """
    Calculate the byte wise exclusive of of two :class:`bytes` objects
    of the same length.
    """
    assert len(a) == len(b)
    return bytes(map(operator.xor, a, b))