Should it be possible to copy empty attachments between instances?

[tamc]

I expected the following to work:

class Thing < ActiveRecord::Base
  has_attached_file :file
end

original = Thing.create
copy = Thing.new
copy.file = original.file
copy.save

Minimum code to turn this into a working example here: https://gist.github.com/3037822

However, it doesn't, it throws:

paperclip-3.1.2/lib/paperclip/tempfile_factory.rb:14:in `extname': can't convert nil into String (TypeError)

Before I write a test and propose a patch, I just wanted to check that everyone agrees that this is a bug and not deliberate in some way that I'm too dense to spot.

Thanks

Tom

[jyurek]

Yes, this is something that should work in Paperclip. If you want to write a fix, it would be greatly appreciated.

[sikachu]

Wait @jyurek , is this something that should work in AttachmentAdapter?