visualizer

# File actionpack/lib/action_dispatch/journey/gtg/transition_table.rb, line 125
        def visualizer(paths, title = "FSM")
          viz_dir   = File.join __dir__, "..", "visualizer"
          fsm_js    = File.read File.join(viz_dir, "fsm.js")
          fsm_css   = File.read File.join(viz_dir, "fsm.css")
          erb       = File.read File.join(viz_dir, "index.html.erb")
          states    = "function tt() { return #{to_json}; }"

          fun_routes = paths.sample(3).map do |ast|
            ast.filter_map { |n|
              case n
              when Nodes::Symbol
                case n.left
                when ":id" then rand(100).to_s
                when ":format" then %{ xml json }.sample
                else
                  "omg"
                end
              when Nodes::Terminal then n.symbol
              else
                nil
              end
            }.join
          end

          stylesheets = [fsm_css]
          svg         = to_svg
          javascripts = [states, fsm_js]

          fun_routes  = fun_routes
          stylesheets = stylesheets
          svg         = svg
          javascripts = javascripts

          require "erb"
          template = ERB.new erb
          template.result(binding)
        end