# File lib/bundler/cli.rb, line 711
    def viz
      require 'graphviz'
      output_file = File.expand_path(options[:file])
      graph = Graph.new(Bundler.load, output_file, options[:version], options[:requirements], options[:format])
      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 "Please install GraphViz. On a Mac with homebrew, you can run `brew install graphviz`."
      else
        raise
      end
    end