class Cucumber::Cli::Configuration

def arrange_formats
  @options[:formats] << ['pretty', @out_stream] if @options[:formats].empty?
  @options[:formats] = @options[:formats].sort_by{|f| f[1] == @out_stream ? -1 : 1}
  streams = @options[:formats].map { |(_, stream)| stream }
  if streams != streams.uniq
    raise "All but one formatter must use --out, only one can print to each stream (or STDOUT)"
  end
end