Minor improvement to digital factory

spec/factories/digital_factory.rb

@@ -2,5 +2,8 @@ FactoryGirl.define do
   factory :digital, :class => Spree::Digital do |f|
     # TODO good to assign variant association if no association is manually defined
     # f.variant { |p| p.association(:variant) }
+
+    attachment_content_type 'application/octet-stream'
+    attachment_file_name 'a_great_book.epub'
   end
 end