Deface + cache = undefined method 'html_safe' for nil:NilClass

[jagthedrummer]

I'm trying to implement Russian doll style fragment caching in my Spree app. In general this works really well, but I'm running into problems when I have a Deface override that tries to alter something inside of a <% cache ... %> block.

For example, I'm trying to use the spree_wishlist gem, which contains this override:

Deface::Override.new(:virtual_path => "spree/products/show",
                 :name => "add_wish_to_cart_form",
                 :insert_bottom => "[data-hook='cart_form']",
                 :partial => "spree/products/wishlist_form",
                 :disabled => false)

I have a custom version of views/spree/products/show.html.erb that looks something like this:

<% cache @product %>
  ...
  <div id="cart-form" class="productcontrols" data-hook="cart_form">
  ...
  </div>
  ...
<% end %>

If I comment out the override in the spree_wishlist gem then the products/show pages will load. OR if I uncomment the override code, but remove the cache block the products/show pages will also load. With both the override in place and the cache block present I get the following stack trace. Is there a way to use Deface and fragment caching together?

undefined method `html_safe' for nil:NilClass

Extracted source (around line #35):

32:     
33:           <div id="content" class='span<%= !content_for?(:sidebar) ? "12" : "12" %>' data-hook>
34:             <%= flash_messages %>
35:               <%= yield %>
36:             </div>
37:         </div>
38:       <%= render :partial => 'spree/shared/footer' %>

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[huoxito]

hey @jagthedrummer thanks for the report interesting issue. Couldn't get that error yet though (I tried with spree_auth_device overrides) will try again with your spree wishlist example. Honestly I can't tell if deface works with rails cache out of the box but it sounds like something worth looking into.

[radar]

Hey @jagthedrummer, do you have an application which reproduces this problem? That'd be a great help.