watch: import_eml: avoid Eml dup for non-scrub case

Most inboxes don't use filters, so the destructive ->scrub won't
be called and we can avoid duplicating the Eml object in the
common case.  We'll also drop the last inbox optimization for
net_cb since it's likely unnecessary given that filters are not
very common.

This may be more noticeable for users who map multiple inboxes
to a single Maildir|IMAP|NNTP source.

diff --git a/lib/PublicInbox/Watch.pm b/lib/PublicInbox/Watch.pm
index c270f5870eb12e76c69f2681ec2484ff65399262..a37038b598c995dbb978d4d32966a1b507a70fe3 100644 (file)
--- a/lib/PublicInbox/Watch.pm
+++ b/lib/PublicInbox/Watch.pm
@@ -222,8 +222,10 @@ sub import_eml ($$$) {
        eval {
                my $im = _importer_for($self, $ibx);
                if (my $filter = $ibx->filter($im)) {
-                       my $ret = $filter->scrub($eml) or return;
+                       my $tmp = PublicInbox::Eml->new(\($eml->as_string));
+                       my $ret = $filter->scrub($tmp) or return;
                        $ret == REJECT and return;
+                       $eml = $tmp;
                }
                $im->add($eml, $self->{spamcheck});
        };
@@ -263,9 +265,9 @@ sub _try_path ($$) {
                $warn_cb->($pfx, "path: $path\n", @_);
        };
        return _remove_spam($self, $path) if $inboxes eq 'watchspam';
+       my $eml = eml_from_path($path) or return;
        for my $ibx (@$inboxes) {
-               my $eml = eml_from_path($path) or next;
-               import_eml($self, $ibx, $eml); # $eml may be scrubbed
+               import_eml($self, $ibx, $eml);
        }
        1;
 }
@@ -323,13 +325,9 @@ sub net_cb { # NetReader::(nntp|imap)_each callback
        return if grep(/\Adraft\z/, @$kw);
        local $self->{cur_uid} = $art; # IMAP UID or NNTP article
        if (ref($inboxes)) {
-               my @ibx = @$inboxes;
-               my $last = pop @ibx;
-               for my $ibx (@ibx) {
-                       my $tmp = PublicInbox::Eml->new(\($eml->as_string));
-                       import_eml($self, $ibx, $tmp);
+               for my $ibx (@$inboxes) {
+                       import_eml($self, $ibx, $eml);
                }
-               import_eml($self, $last, $eml);
        } elsif ($inboxes eq 'watchspam') {
                if ($uri->scheme =~ /\Aimaps?\z/ && !grep(/\Aseen\z/, @$kw)) {
                        return;