fixes #1473

app/models/tag_implication.rb

@@ -1,6 +1,8 @@
 class TagImplication < ActiveRecord::Base
   before_save :update_descendant_names
   after_save :update_descendant_names_for_parent
+  after_destroy :update_descendant_names_for_parent
+  after_destroy :update_posts_for_destroy
   belongs_to :creator, :class_name => "User"
   before_validation :initialize_creator, :on => :create
   before_validation :normalize_names
@@ -90,13 +92,41 @@ class TagImplication < ActiveRecord::Base
         q = q.where("antecedent_name = ?", params[:antecedent_name])
       end
 
+      if params[:consequent_name].present?
+        q = q.where("consequent_name = ?", params[:consequent_name])
+      end
+
       q
     end
   end
 
+  module DeletionMethods
+    extend ActiveSupport::Concern
+
+    module ClassMethods
+      def update_posts_for_destroy(creator_id, creator_ip_addr, tag_name)
+        Post.tag_match("#{tag_name} status:any").find_each do |post|
+          escaped_tag_name = Regexp.escape(tag_name)
+          fixed_tags = post.tag_string.sub(/(?:\A| )#{escaped_tag_name}(?:\Z| )/, " ").strip
+          CurrentUser.scoped(User.find(creator_id), creator_ip_addr) do
+            post.disable_versioning = true
+            post.update_attributes(
+              :tag_string => fixed_tags
+            )
+          end
+        end
+      end
+    end
+
+    def update_posts_for_destroy
+      TagImplication.delay(:queue => "default").update_posts_for_destroy(CurrentUser.user.id, CurrentUser.ip_addr, consequent_name)
+    end
+  end
+
   include DescendantMethods
   include ParentMethods
   extend SearchMethods
+  include DeletionMethods
 
   def initialize_creator
     self.creator_id = CurrentUser.user.id
@@ -105,7 +135,7 @@ class TagImplication < ActiveRecord::Base
 
   def process!
     update_column(:status, "processing")
-    update_posts
+    update_posts_for_create
     update_column(:status, "active")
     update_descendant_names_for_parent
   rescue Exception => e
@@ -120,7 +150,7 @@ class TagImplication < ActiveRecord::Base
     end
   end
 
-  def update_posts
+  def update_posts_for_create
     Post.tag_match("#{antecedent_name} status:any").find_each do |post|
       escaped_antecedent_name = Regexp.escape(antecedent_name)
       fixed_tags = post.tag_string.sub(/(?:\A| )#{escaped_antecedent_name}(?:\Z| )/, " #{antecedent_name} #{descendant_names} ").strip