Gary cool thanks, sure I can write a test, it was a very straight forward change that's why I didn't wrote one, I have been using this in our build system for a few months now. And I was going through documentation stage of our insite SCons tool and thought it could be interesting to other. I will write the unit test and send back, I verified none of the other tests got broken, but agree we need a test.
Also I have to ask my superiors on which parts we can contribute back, our tool handles things like configuring arm-none-eabi-gcc for ARM targets, some automated C/C++ unit tests and some bug fixes for qt tool. Would love to contribute back, that way I would not only get feedback from people with more knoweledge on SCons internals, but also if lucky get help maintaing :D.