Rubocop

app/models/application_record.rb

@@ -32,7 +32,7 @@ class ApplicationRecord < ActiveRecord::Base
   end
 
   def self.sanitize_sql_in(ary)
-    return "(NULL)" unless ary.present? && ary.respond_to?(:map)
+    return '(NULL)' unless ary.present? && ary.respond_to?(:map)
 
     ary = ary.map { |el| ActiveRecord::Base.sanitize_sql_array(['?', el]) }
     "(#{ary.join(', ')})"

app/models/tag.rb

 class Tag < ApplicationRecord
   include CommunityRelated
 
-  scope :category_order, -> (required_ids, topic_ids) do
-    helpers = ActionController::Base.helpers
+  scope :category_order, lambda { |required_ids, topic_ids|
     order(Arel.sql("id IN #{sanitize_sql_in(required_ids)} DESC"),
           Arel.sql("id IN #{sanitize_sql_in(topic_ids)} DESC"),
           name: :asc)
-  end
+  }
 
   has_and_belongs_to_many :posts
   belongs_to :tag_set