Scope for Polymorphic association + ManyToMany

[USvER]

I have this setup: "Topic" and "Comment" has many "Assets" through polymorphic join table.
I want my topics and comments to have their assets ordered. To make my act_as_list work for Topics and Comments separately it should use default scope. How to do that?

[USvER]

Hm... i guess i need to define position on the join model itself for that to work...

[swanandp]

I think the gem should support lambdas for scopes. With that, you can just define your own scope.

[USvER]

Polimorphic relation(or maybe all relations) is scopes by itself. So i have defined polimorphic relation as "holder". So asset has holder, wich can be either Topic or Comment... This way i just do

belongs_to :holder, polymorphic: true
acts_as_list scope: :holder

And all works... Still lambdas may be a good idea = )
Thank you!

[firedev]

I use it the same way:

belongs_to :imageable, polymorphic: true
acts_as_list scope :imageable

However Rails 4 complaints:

DEPRECATION WARNING: Calling #scope or #default_scope with a hash is deprecated. Please use a lambda containing a scope. E.g. scope :red, -> { where(color: 'red') }.

What would be the right syntax here?

[firedev]

Even worse Rails 4.1 simply rejects it:

`scope': wrong number of arguments (0 for 2) (ArgumentError)

Suggestions?

[firedev]

Anyway, I did it like this:

  acts_as_list scope :imageable, -> { includes :imageable }

[firedev]

Okay, upon further investigation I have figured out that it simply doesn't work. It reorders all images ignoring the scope. Switched to ranked-model. Took a few minutes.

[firedev]

Probably worth checking, however this is for Rails 3 http://jakeboxer.com/blog/2011/10/09/using-acts-as-list-in-a-polymorphic-scope/

class Picture < ActiveRecord::Base
  belongs_to :imageable, polymorphic: true
  acts_as_list scope: [:imageable_id, :imageable_type]
end

[USvER]

@firedev hm, strange... i didn't had this issue... just used as usual scope...

[Feuda]

@firedev

acts_as_list scope: [:imageable_id, :imageable_type]

This worked in rails4!

[firedev]

Guess this was fixed since.

[swanandp]

Closing.