In general the whole govspeak preprocess is a bit ugly. 

For this class inclusion you could do something like:


    type = case $1.include?
           when 'stacked'
             ' .mc-stacked'
           when 'compact'
             ' .compact'
           when 'negative'
             ' .mc-negative'

    classline = [ 
                  '{: .js-barchart-table', 
                  type, 
                  ' .left-key', 
                  ' .mc-auto-outdent',
                  '}'
                ].join()