instance method config_when_updating

# File railties/lib/rails/generators/rails/app/app_generator.rb, line 115
    def config_when_updating
      cookie_serializer_config_exist = File.exist?("config/initializers/cookies_serializer.rb")
      action_cable_config_exist = File.exist?("config/cable.yml")
      rack_cors_config_exist = File.exist?("config/initializers/cors.rb")
      assets_config_exist = File.exist?("config/initializers/assets.rb")
      new_framework_defaults_5_1_exist = File.exist?("config/initializers/new_framework_defaults_5_1.rb")

      config

      unless cookie_serializer_config_exist
        gsub_file "config/initializers/cookies_serializer.rb", /json(?!,)/, "marshal"
      end

      unless action_cable_config_exist
        template "config/cable.yml"
      end

      unless rack_cors_config_exist
        remove_file "config/initializers/cors.rb"
      end

      if options[:api]
        unless cookie_serializer_config_exist
          remove_file "config/initializers/cookies_serializer.rb"
        end

        unless assets_config_exist
          remove_file "config/initializers/assets.rb"
        end

        # Sprockets owns the only new default for 5.1:
        # In API-only Applications, we don't want the file.
        unless new_framework_defaults_5_1_exist
          remove_file "config/initializers/new_framework_defaults_5_1.rb"
        end
      end
    end