url_for() produces path with double namespace

[cristian-rivera]

I have routes defined like this:

 namespace :dealer, path: '' do
   resources :images, except: :index do
     resources :comments, only: [:create, :destroy] do
       resources :attachments, only: :show
     end
   end
 end

In my view using link_to [@image, @comment] results in a url named:

dealer_image_dealer_comment_path which doesn't exist. It should be dealer_image_comment_path. Any way to avoid the double namespace?

I'm receiving this error:

undefined method `dealer_image_dealer_comment_path' for #<#<Class:0x007fb599499520>:0x007fb5994980d0>
Did you mean?  dealer_image_comments_path
               dealer_image_comment_path

rake routes:

dealer_image_comments POST      /images/:image_id/comments(.:format)                                                                   dealer/comments#create {:subdomain=>"dealer"}
dealer_image_comment DELETE    /images/:image_id/comments/:id(.:format) 

Rails version: 5.0.2

Ruby version: 2.4.0

[alexcameron89]

Hey @cristian-rivera, can you provide us with a minimal Rails application so we can reproduce the issue you are seeing?

[cristian-rivera]

Hey @alexcameron89, here is the link to a test repo I setup https://github.com/cristian-rivera/Example just run rails s and navigate to http://lvh.me:3000/dealer/images/1/comments/new!

[pixeltrix]

@cristian-rivera are you using namespaces for your models, e.g. Dealer::Image and Dealer::Comment ? If so this is a limitation of the way polymorphic_url works. It effectively guesses the url helper name based on the model name and namespaces can cause it to go wrong.

[rails-bot]

This issue has been automatically marked as stale because it has not been commented on for at least three months.
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