app_name

# File actionpack/lib/action_dispatch/routing/mapper.rb, line 429
          def app_name(app)
            return unless app.respond_to?(:routes)

            if app.respond_to?(:railtie_name)
              app.railtie_name
            else
              class_name = app.class.is_a?(Class) ? app.name : app.class.name
              ActiveSupport::Inflector.underscore(class_name).gsub("/", "_")
            end
          end