I understand what the point of the test was.  Unfortunately, with the way the filter/handler are designed, combined with the new change that checks if the list is null before processing anything else, we can't actually execute this failure case.

Basically I could execute the failure case because whenever I called init() on the filter with any empty filter config, the entire handler's init would get executed.

With the new code, when you call init, it will call the handler's init (which has already been called once from the setUp() method) which will not execute anything in the if statement since the list is already populated. 

Unless that handler becomes non-static or we always instanciate a new one in init (regardless of the fact that its static and not a member variable), we'll never be able to do this test.