Is there a way to have a build trigger if a change exclusively contains certain filetypes?

Hello,

Is there a way to have a build trigger if a change exclusively contains certain filetypes? 

I want to trigger a build if the change from perforce only has *.uasset files in it, but not if there are any other file types in the change list.

For example this change would trigger a build:

cool_asset.uasset
reall_cool_asset.uasset

but this change would not trigger a build:

cool_asset.uasset
reall_cool_asset.uasset
cool_code_file.h
cool_code_file.cpp

and neither would this change:

cool_code_file.h
cool_code_file.cpp

So far I have tried adjusting the VCS trigger rules in the following ways:

+:**.uasset

-:**.h
-:**.cpp

+:**.uasset
-:**.h
-:**.cpp

All of which work for the first and third example, but still trigger a build for the second example.

Any help would be appreciated.