'''UnitTest'''ing appears to focus primarily on unit testing on a class by class basis. The class is the unit of test. How does unit testing address AspectOrientedProgramming, which by definition modifies the behavior across several objects?'''

The UnitTest''''''s for aspects of objects are aspects of the unit tests of the objects.

Simple, eh?

No, seriously, it is:

You have a unit test for an object.  You define an aspect which applies to that object.  To test the aspect, you write another aspect which applies to the tests of those objects.