#282

backend/app/models/tag.rb

@@ -23,6 +23,8 @@ class Tag < ApplicationRecord
   has_many :parents, through: :reversed_tag_implications, source: :parent_tag
 
   has_many :tag_similarities, dependent: :delete_all
+  has_many :tag_similarities_as_target,
+           class_name: 'TagSimilarity', foreign_key: :target_tag_id, dependent: :delete_all
 
   has_many :deerjikists, dependent: :delete_all
 
@@ -140,7 +142,7 @@ class Tag < ApplicationRecord
     retry
   end
 
-  def self.merge_tags target_tag, source_tags
+  def self.merge_tags! target_tag, source_tags
     target_tag => Tag
 
     Tag.transaction do
@@ -166,6 +168,8 @@ class Tag < ApplicationRecord
       end
     end
 
+    target_tag.update!(post_count: PostTag.kept.where(tag: target_tag).count)
+
     target_tag
   end