def evaluate(context, locals, &block)
      return data unless stylus_file?(context)

      depend_on(context, data)
      data
    end
def evaluate(context, locals, &block)
      return data unless stylus_file?(context)

      depend_on(context, data)
      data
    end
Public: Scans the current stylesheet to track down Stylus
 '@import' calls as dependencies.

 Returns the stylesheet content, unmodified.