Stubbing Paperclip S3 requests in specs

Question

I am using Paperclip and S3 for image uploads and am trying to stub out calls to S3 from my test suite. I found the thoughtbot post which mentions doing

  a.cover       { a.paperclip_fixture('album', 'cover', 'png') }

but that gives me a "wrong number of arguments (4 for 2)" error. I tried switching the arguments above to an array, which removes the original error, but gives an error saying "Attribute already defined: paperclip_fixture".

Has anyone been able to get this working? Also, I'd ideally like to use the local filesystem for the development environment. Is there an easy way to do this?