S3 publishing endpoint appears to reupload everything

[MMartyn]

I am investigating slowness around publishing new snapshots to s3. I turned on debugging and the ListObjects call appeared to double up on the prefix ie
GET /?max-keys=1000&prefix={prefix}%2F{prefix}%2F.

As far as I can tell I have the s3 endpoint configured correctly and I am not sending a prefix in the command but do have the prefix configured in the endpoint.

Unless I am reading the code incorrectly it looks like that is happening as a result of these 2 lines:
https://github.com/smira/aptly/blob/master/s3/public.go#L270
https://github.com/smira/aptly/blob/master/s3/public.go#L325

[smira]

thanks, nice catch!

there's no error but it gets empty listing and decides to re-upload everything :(