base_helper_decorator.rb

# link to cart better
Spree::BaseHelper.module_eval do

    def taxons_tree(root_taxon, current_taxon, max_level = 1, root_css_class = nil)
      return '' if max_level < 1 || root_taxon.children.empty?
      content_tag :ul, :class => root_css_class do
        root_taxon.children.map do |taxon|
          css_class = (taxon.children.empty? || max_level < 2) ? "no_sub_menu" : "has_sub_menu"
          i_class = (css_class == "no_sub_menu") ? "fi-minus" : "fi-plus"
          content_tag :li, :class => css_class do
            content_tag(:i, :class => "nav-collapse " + i_class) do end +
            link_to(taxon.name, seo_url(taxon)) +
            taxons_tree(taxon, current_taxon, max_level - 1, "nested")
          end
        end.join("\n").html_safe
      end
    end
end