# File lib/brakeman/tracker/config.rb, line 81
    def set_rails_version
      # Ignore ~>, etc. when using values from Gemfile
      version = gem_version(:rails) || gem_version(:railties)
      if version and version.match(/(\d+\.\d+(\.\d+.*)?)/)
        @rails_version = $1

        if tracker.options[:rails3].nil? and tracker.options[:rails4].nil?
          if @rails_version.start_with? "3"
            tracker.options[:rails3] = true
            Brakeman.notify "[Notice] Detected Rails 3 application"
          elsif @rails_version.start_with? "4"
            tracker.options[:rails3] = true
            tracker.options[:rails4] = true
            Brakeman.notify "[Notice] Detected Rails 4 application"
          elsif @rails_version.start_with? "5"
            tracker.options[:rails3] = true
            tracker.options[:rails4] = true
            tracker.options[:rails5] = true
            Brakeman.notify "[Notice] Detected Rails 5 application"
          end
        end
      end

      if get_gem :rails_xss
        @escape_html = true
        Brakeman.notify "[Notice] Escaping HTML by default"
      end
    end