Merge pull request #806 from ProGM/fix-caching-tag-list-on-bug

Fix `caching_tag_list_on?` bug (#432)

lib/acts_as_taggable_on/taggable/core.rb

@@ -275,7 +275,7 @@ def tag_list_cache_on(context)
       variable_name = "@#{context.to_s.singularize}_list"
       if instance_variable_get(variable_name)
         instance_variable_get(variable_name)
-      elsif cached_tag_list_on(context) && self.class.caching_tag_list_on?(context)
+      elsif cached_tag_list_on(context) && ensure_included_cache_methods! && self.class.caching_tag_list_on?(context)
         instance_variable_set(variable_name, ActsAsTaggableOn.default_parser.new(cached_tag_list_on(context)).parse)
       else
         instance_variable_set(variable_name, ActsAsTaggableOn::TagList.new(tags_on(context).map(&:name)))
@@ -418,6 +418,10 @@ def save_tags
 
     private
 
+    def ensure_included_cache_methods!
+      self.class.columns
+    end
+
     # Filters the tag lists from the attribute names.
     def attributes_for_update(attribute_names)
       tag_lists = tag_types.map {|tags_type| "#{tags_type.to_s.singularize}_list"}

spec/acts_as_taggable_on/caching_spec.rb

@@ -99,6 +99,24 @@
     end
   end
 
+  describe 'Cache methods initialization on new models' do
+    before(:all) do
+      ActiveRecord::Base.connection.execute(
+        'INSERT INTO cache_methods_injected_models (cached_tag_list) VALUES (\'ciao\')'
+      )
+      class CacheMethodsInjectedModel < ActiveRecord::Base
+        acts_as_taggable
+      end
+    end
+    after(:all) { Object.send(:remove_const, :CacheMethodsInjectedModel) }
+
+    it 'cached_tag_list_on? get injected correctly' do
+      expect do
+        CacheMethodsInjectedModel.first.tag_list
+      end.not_to raise_error
+    end
+  end
+
   describe 'CachingWithArray' do
     pending '#TODO'
   end

spec/internal/db/schema.rb

@@ -78,6 +78,9 @@
     t.column :type, :string
   end
 
+  create_table :cache_methods_injected_models, force: true do |t|
+    t.column :cached_tag_list, :string
+  end
 
   # Special cases for postgresql
   if using_postgresql?