Move after_save callback to HasAttachedFile

lib/paperclip.rb

@@ -175,7 +175,6 @@ module Paperclip
     def has_attached_file(name, options = {})
       HasAttachedFile.define_on(self, name, options)
 
-      after_save { send(name).send(:save) }
       before_destroy { send(name).send(:queue_all_for_delete) }
       after_destroy { send(name).send(:flush_deletes) }
 

lib/paperclip/has_attached_file.rb

@@ -17,6 +17,7 @@ module Paperclip
       define_query
       check_for_path_clash
       register_with_rake_tasks
+      add_active_record_callbacks
     end
 
     private
@@ -72,5 +73,10 @@ module Paperclip
     def register_with_rake_tasks
       Paperclip::Tasks::Attachments.add(@klass, @name, @options)
     end
+
+    def add_active_record_callbacks
+      name = @name
+      @klass.send(:after_save) { send(name).send(:save) }
+    end
   end
 end

test/has_attached_file_test.rb

@@ -26,6 +26,10 @@ class HasAttachedFileTest < Test::Unit::TestCase
     should 'register the attachment with Paperclip::Tasks' do
       assert_adding_attachment('avatar').registers_with_tasks
     end
+
+    should 'define an after_save callback' do
+      assert_adding_attachment('avatar').defines_callback('after_save')
+    end
   end
 
   private
@@ -84,12 +88,23 @@ class HasAttachedFileTest < Test::Unit::TestCase
       end
     end
 
+    def defines_callback(callback_name)
+      a_class = stub_class
+
+      Paperclip::HasAttachedFile.define_on(a_class, @attachment_name, {})
+
+      assert_received(a_class, callback_name.to_sym)
+    end
+
     private
 
     def stub_class
       stub('class',
            validates_each: nil,
            define_method: nil,
+           after_save: nil,
+           before_destroy: nil,
+           after_destroy: nil,
            name: 'Billy')
     end
   end