FIX: automatically in/decrement topic_tags.pm_topic_count

app/models/topic_tag.rb

@@ -3,26 +3,34 @@ class TopicTag < ActiveRecord::Base
   belongs_to :tag
 
   after_create do
-    if topic && topic.archetype != Archetype.private_message
-      tag.increment!(:topic_count)
+    if topic
+      if topic.archetype == Archetype.private_message
+        tag.increment!(:pm_topic_count)
+      else
+        tag.increment!(:topic_count)
 
-      if topic.category_id
-        if stat = CategoryTagStat.where(tag_id: tag_id, category_id: topic.category_id).first
-          stat.increment!(:topic_count)
-        else
-          CategoryTagStat.create(tag_id: tag_id, category_id: topic.category_id, topic_count: 1)
+        if topic.category_id
+          if stat = CategoryTagStat.find_by(tag_id: tag_id, category_id: topic.category_id)
+            stat.increment!(:topic_count)
+          else
+            CategoryTagStat.create(tag_id: tag_id, category_id: topic.category_id, topic_count: 1)
+          end
         end
       end
     end
   end
 
   after_destroy do
-    if topic && topic.archetype != Archetype.private_message
-      if topic.category_id && stat = CategoryTagStat.where(tag_id: tag_id, category: topic.category_id).first
-        stat.topic_count == 1 ? stat.destroy : stat.decrement!(:topic_count)
-      end
+    if topic
+      if topic.archetype == Archetype.private_message
+        tag.decrement!(:pm_topic_count)
+      else
+        if topic.category_id && stat = CategoryTagStat.find_by(tag_id: tag_id, category: topic.category_id)
+          stat.topic_count == 1 ? stat.destroy : stat.decrement!(:topic_count)
+        end
 
-      tag.decrement!(:topic_count)
+        tag.decrement!(:topic_count)
+      end
     end
   end
 end

lib/discourse_tagging.rb

@@ -181,9 +181,7 @@ module DiscourseTagging
   end
 
   def self.hidden_tag_names(guardian = nil)
-    return [] if guardian&.is_staff?
-
-    hidden_tags_query.pluck(:name)
+    guardian&.is_staff? ? [] : hidden_tags_query.pluck(:name)
   end
 
   def self.hidden_tags_query