Hi
With dovecot 2.2.5, and dovecot-antispam built from a recent HEAD pull, when copying multiple messages to or from a Spam folder, the plugin sends multiple copies of the first message to the backend. I've tried this with the pipe and spool2dir backends.
For example with the spool2dir backend, via IMAP doing
A COPY 1:3 Spam
yields 3 copies of message id 1 in the dir: dev:imap-8.1 rplatel@imap01:/var/run/dovecot_as_tmp$ sudo -u mail md5sum * 28ad0a215eb7ecbd3a814a8a334d85bf 00000000001385586164-rplatel@ff-dev.com-00001s 28ad0a215eb7ecbd3a814a8a334d85bf 00000000001385586164-rplatel@ff-dev.com-00002s 28ad0a215eb7ecbd3a814a8a334d85bf 00000000001385586164-rplatel@ff-dev.com-00003s
I see the same behaviour with the pipe backend, the pipe program is invoked 3 times, but with the same message content.