Move issues sort logic to Issuable concern

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

app/contexts/issues/list_context.rb

@@ -31,23 +31,9 @@ module Issues
       end
 
       # Sort by :sort param
-      @issues = sort(@issues, params[:sort])
+      @issues = @issues.sort(params[:sort])
 
       @issues
     end
-
-    private
-
-    def sort(issues, condition)
-      case condition
-      when 'newest' then issues.except(:order).order('created_at DESC')
-      when 'oldest' then issues.except(:order).order('created_at ASC')
-      when 'recently_updated' then issues.except(:order).order('updated_at DESC')
-      when 'last_updated' then issues.except(:order).order('updated_at ASC')
-      when 'milestone_due_soon' then issues.except(:order).joins(:milestone).order("milestones.due_date ASC")
-      when 'milestone_due_later' then issues.except(:order).joins(:milestone).order("milestones.due_date DESC")
-      else issues
-      end
-    end
   end
 end

app/models/concerns/issuable.rb

@@ -45,6 +45,18 @@ module Issuable
     def search(query)
       where("title like :query", query: "%#{query}%")
     end
+
+    def sort(method)
+      case method.to_s
+      when 'newest' then reorder('created_at DESC')
+      when 'oldest' then reorder('created_at ASC')
+      when 'recently_updated' then reorder('updated_at DESC')
+      when 'last_updated' then reorder('updated_at ASC')
+      when 'milestone_due_soon' then joins(:milestone).reorder("milestones.due_date ASC")
+      when 'milestone_due_later' then joins(:milestone).reorder("milestones.due_date DESC")
+      else reorder('created_at DESC')
+      end
+    end
   end
 
   def today?