Question

When you have a partial in

/app/views/posts/comments/_comment.html.erb,

doing the following

<%= render @post.comments %>

iterates the @post.comments collection like

@post.comments.each do |comment|

automatically, even if you don’t pass in the collection into the partial.

However, this will render the comments in the other direction, because of the way objects are sorted by created_at.

I want to change the direction: sort the collection in the other way by created_at DESC, and then iterate the comments collection.

I would do

@comments = @post.comments.paginate(:page => params[:page], :per_page => 10, :order => "created_at") in the PostsContoller and <%= render @comments %> instead of <%= @post.comments %>, but I was curious if there were any more common way of doing this.

Thanks in advance!

Answer 1

You definitely want to do:

@comments = @post.comments.order("created_at ASC").paginate(page: params[:page])

instead of changing how a Rails helper works! Why would you do that?

You can define how comments are ordered on the association. In the Post model:

has_many :comments, order: "comments.created_at ASC"

You can also set a default scope to change how the comments are ordered by default.

In the model:

default_scope order('created_at ASC')