mbox: do not try to create filename from empty string

[public-inbox.git] / lib / PublicInbox / Mbox.pm

diff --git a/lib/PublicInbox/Mbox.pm b/lib/PublicInbox/Mbox.pm
index 42cedd15f5dead4a73170094327501f12111d983..c50a118b2b6367200767ea929ba97596bd1713c5 100644 (file)
--- a/lib/PublicInbox/Mbox.pm
+++ b/lib/PublicInbox/Mbox.pm
@@ -18,7 +18,7 @@ use Email::MIME::Encode;
 sub subject_fn ($) {
        my ($hdr) = @_;
        my $fn = $hdr->header('Subject');
-       return 'no-subject' unless defined($fn);
+       return 'no-subject' if (!defined($fn) || $fn eq '');
 
        # no need for full Email::MIME, here
        if ($fn =~ /=\?/) {