Simple mocking in Python

mock.py

import contextlib

@contextlib.contextmanager
def mock_attr(object_, orig_attr_name, mock_attr):
    """
    Temporarily mock object attribute for testing

    This is similiar to the unittest.patch.object in Python 3.3 just much
    simpler for our limited needs and use in Python 2.7.

    :param object_: Object holding reference to attribute to mock
    :param orig_attr_name: Name of original attribute to mock
    :param mock_attr: Object to mock attribute with
    """

    orig_attr = getattr(object_, orig_attr_name)
    setattr(object_, orig_attr_name, mock_attr)

    try:
        yield object_
    finally:
        setattr(object_, orig_attr_name, orig_attr)