adds 'most commented' order to debates

app/controllers/debates_controller.rb

@@ -82,7 +82,7 @@ class DebatesController < ApplicationController
     end
 
     def parse_order
-      @valid_orders = ['created_at', 'score']
+      @valid_orders = ['created_at', 'score', 'most_commented']
       @order = @valid_orders.include?(params[:order]) ? params[:order] : 'created_at'
     end
 

app/models/debate.rb

@@ -30,6 +30,7 @@ class Debate < ActiveRecord::Base
   scope :for_render, -> { includes(:tags) }
   scope :sort_by_score , -> { reorder(cached_votes_score: :desc) }
   scope :sort_by_created_at, -> { reorder(created_at: :desc) }
+  scope :sort_by_most_commented, -> { reorder(comments_count: :desc) }
 
   # Ahoy setup
   visitable # Ahoy will automatically assign visit_id on create