+
+ my $set = eml_load('t/plack-qp.eml');
+ $set->header_set('Message-ID', "<set\@$parallel>");
+ my $ret = $lst->set_eml($set, 'seen');
+ is(ref $ret, 'PublicInbox::Smsg', 'initial returns smsg');
+ my $ids = $lst->set_eml($set, qw(seen));
+ is_deeply($ids, [ $ret->{num} ], 'set_eml idempotent');
+ $ids = $lst->set_eml($set, qw(seen answered));
+ is_deeply($ids, [ $ret->{num} ], 'set_eml to change kw');
+ $lst->done;
+ @kw = $lst->search->msg_keywords($ids->[0]);
+ is_deeply(\@kw, [qw(answered seen)], 'set changed kw');