apply_form_for_options!

# File actionpack/lib/action_view/helpers/form_helper.rb, line 380
      def apply_form_for_options!(object_or_array, options) #:nodoc:
        object = object_or_array.is_a?(Array) ? object_or_array.last : object_or_array
        object = convert_to_model(object)

        as = options[:as]
        action, method = object.respond_to?(:persisted?) && object.persisted? ? [:edit, :put] : [:new, :post]
        options[:html].reverse_merge!(
          :class  => as ? "#{as}_#{action}" : dom_class(object, action),
          :id     => as ? "#{as}_#{action}" : dom_id(object, action),
          :method => method
        )

        options[:url] ||= polymorphic_path(object_or_array, :format => options.delete(:format))
      end