Better formatting expected vs. actual method call

[ivancrneto]

What steps will reproduce the problem?
Mock a given method that has a long and complex signature, and have the
actual call to the mock not match the recorded call.

mock_my_object = self.mox.create_mock(MyObject)
mock_my_object.some_complex_method(1, 2, 3, 4, 5, 6).returns(True)
self.mox.replay_all()

assert mock_my_object.some_complex_method(1, 2, 3, 4, 5, 6, 7))

Something like this would be nice:

Expected <MyObject mock>.SomeComplexMethod(1, 2, 3, 4, 5, 6)
Actual   <MyObject mock>.SomeComplexMethod(1, 2, 3, 4, 5, 6, 7)
                                            Extra parameter /|\

Check if this is still the case.