    # File lib/action_view/helpers/form_tag_helper.rb, line 399
          def image_submit_tag(source, options = {})
            options.stringify_keys!

            if confirm = options.delete("confirm")
              options["onclick"] ||= ''
              options["onclick"] += "return #{confirm_javascript_function(confirm)};"
            end

            tag :input, { "type" => "image", "src" => path_to_image(source) }.update(options.stringify_keys)
          end