undefined method `each' for nil:NilClass in Spree

Question

In Spree Store I have a side bar composed by Taxonomies. Example: Food (taxonomy) |-hamburguer |-french fries

I took the side bar made by taxonomies and I applied the code to build a customized bootstrap menu. And to do that I did that following:

I took the code bellow from _taxonomies.html.rb:

<% max_level = Spree::Config[:max_level_in_taxons_menu] || 1 %>
<nav id="taxonomies" class="sidebar-item" data-hook>
  <% @taxonomies.each do |taxonomy| %>
    <% cache [I18n.locale, taxonomy, max_level] do %>
      <h6 class='taxonomy-root'><%= Spree.t(:shop_by_taxonomy, :taxonomy => taxonomy.name) %></h6>
      <%= taxons_tree(taxonomy.root, @taxon, max_level) %>
    <% end %>
  <% end %>
</nav>

And I did it:(putting it in a _main_bar_menu.html.rb file)

<% max_level = Spree::Config[:max_level_in_taxons_menu] || 1 %>
<nav class="columns sixteen">
<nav id="taxonomies" class="navbar navbar-default" data-hook>
    <div class="container-fluid">
        <div class="navbar-header">
            <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" 
            data-target="#menu-produtos-taxonomi" aria-expanded="false">
                <span class="sr-only">Toggle navigation</span>
                <span class="icon-bar"></span>
                <span class="icon-bar"></span>
                <span class="icon-bar"></span>
            </button>
        </div>
        <div class="collapse navbar-collapse" id="menu-produtos-taxonomi">
            <ul class="nav navbar-nav">
                <li id="home-link" data-hook><%= link_to Spree.t(:home), spree.root_path %></li>    
                <% @taxonomies.each do |taxonomy| %>
                    <% cache [I18n.locale, taxonomy, max_level] do %>
                    <li class="dropdown">
                        <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" 
                            aria-haspopup="true" aria-expanded="false">
                            <%= Spree.t(:shop_by_taxonomy_only_name, :taxonomy => taxonomy.name) %> 
                            <span class="caret"></span>
                        </a>
                        <%= taxons_tree_menu(taxonomy.root, @taxon, max_level) %>
                    </li>
                    <% end %>
                <% end %>   
            </ul>
        </div>
    </div>
</nav>
</nav>

After that, every time I try to access a product page with its details(not a page listing the products of the same time), por exemple:

http://localhost:3000/products/soy-milk?taxon_id=3

I get the following error:

undefined method `each' for nil:NilClass

And it is pointing to that line in _main_bar_menu.html.rb (shown above):

<% @taxonomies.each do |taxonomy| %>

I'm a begginer in Ruby on Rails and Spree, and I don't know how to solve that. If you can help me please ... I would appreciate that.

sumit sumit · Accepted Answer · 2016-02-15T03:41:18

<% @taxonomies.each do |taxonomy| %> Please write down this line as <% (@taxonomies || []).each do |taxonomy| %> It will never genrate error of nil

undefined method `each' for nil:NilClass in Spree

3 Answers