I used ['TEST'] as this was common rake testtask - https://github.com/jimweirich/rake/blob/master/lib/rake/testtask.rb#L144

I am reviewing the test setup a little bit and seeing if I can propose something a little bit different leveraging testtask and including the 'test/helper'. I hope to spend a little bit of time on wednesday looking at that further and will repush an additional proposal.