post.rb: handle automatic *_(cosplay) tags in TagImplication.

app/models/post.rb

@@ -636,6 +636,7 @@ class Post < ActiveRecord::Base
       normalized_tags = %w(tagme) if normalized_tags.empty?
       normalized_tags = TagAlias.to_aliased(normalized_tags)
       normalized_tags = add_automatic_tags(normalized_tags)
+      normalized_tags = normalized_tags + TagImplication.automatic_tags_for(normalized_tags)
       normalized_tags = TagImplication.with_descendants(normalized_tags)
       normalized_tags = normalized_tags.compact
       normalized_tags.sort!
@@ -705,10 +706,6 @@ class Post < ActiveRecord::Base
         tags << "ugoira"
       end
 
-      characters = tags.grep(/\A(.+)_\(cosplay\)\Z/) { $1 }
-      tags += characters
-      tags << "cosplay" if characters.present?
-
       return tags
     end
 

app/models/tag_implication.rb

@@ -32,6 +32,12 @@ class TagImplication < ActiveRecord::Base
       def with_descendants(names)
         (names + where("antecedent_name in (?) and status in (?)", names, ["active", "processing"]).map(&:descendant_names_array)).flatten.uniq
       end
+
+      def automatic_tags_for(names)
+        tags = names.grep(/\A(.+)_\(cosplay\)\Z/) { $1 }
+        tags << "cosplay" if tags.present?
+        tags.uniq
+      end
     end
 
     def descendants