replace includes and join parent with eager_load

lib/active_record/acts_as_relation.rb

@@ -13,11 +13,9 @@ def acts_as(model_name, scope = nil, options = {})
         class_eval do
           include ActiveRecord::ActsAsRelation::ActsAsModules[acts_as]
 
-          default_scope -> { includes(acts_as.name) }
+          default_scope -> { eager_load(acts_as.name) }
         end
 
-        class_eval { default_scope -> { joins(acts_as.name) } } if options.fetch :auto_join, true
-
         instance_eval <<-EndCode, __FILE__, __LINE__ + 1
           def acts_as_other_model?
             true

spec/acts_as_relation_spec.rb

@@ -169,10 +169,6 @@
         expect { Pen.where('price > 1').to_a }.not_to raise_error
         expect(Pen.where('name = ?', 'RedPen')).to include(pen)
       end
-
-      it 'can be disabled by setting auto_join option to false' do
-        expect { Pencil.where('name = 1').to_a }.to raise_error(ActiveRecord::StatementInvalid)
-      end
     end
   end
 end