Preserve original mock message

[nicoddemus]

Follow up to #79

def test(mocker):
    m = mocker.Mock()
    m('fo')
    m.assert_called_once_with('', bar=4)

Output:

____________________________________ test _____________________________________

mocker = <pytest_mock.MockFixture object at 0x0381E2D0>

    def test(mocker):
        m = mocker.Mock()
        m('fo')
>       m.assert_called_once_with('', bar=4)
E       AssertionError: Expected call: mock('', bar=4)
E       Actual call: mock('fo')
E
E       pytest introspection follows:
E
E       Args:
E       assert ('fo',) == ('',)
E         At index 0 diff: 'fo' != ''
E         Use -v to get the full diff
E       Kwargs:
E       assert {} == {'bar': 4}
E         Right contains more items:
E         {'bar': 4}
E         Use -v to get the full diff

test_foo.py:6: AssertionError
========================== 1 failed in 0.03 seconds ===========================

cc @txomon @quodlibetor

[quodlibetor]

That looks beautiful.

[nicoddemus]

pytest-mock 1.6.0 is out! 😉