# File lib/bundler/cli.rb, line 570
    def viz
      output_file = File.expand_path(options[:file])
      output_format = options[:format]
      graph = Graph.new(Bundler.load, output_file, options[:version], options[:requirements], options[:format])

      begin
        graph.viz
      rescue LoadError => e
        Bundler.ui.error e.inspect
        Bundler.ui.warn "Make sure you have the graphviz ruby gem. You can install it with:"
        Bundler.ui.warn "`gem install ruby-graphviz`"
      rescue StandardError => e
        if e.message =~ /GraphViz not installed or dot not in PATH/
          Bundler.ui.error e.message
          Bundler.ui.warn "The ruby graphviz gem requires GraphViz to be installed"
        else
          raise
        end
      end
    end