mm: min/max: return 0 instead of undef

This simplifies callers and allows empty newsgroups to be
represented (the WWW UI may be insufficient there, too).

1 files changed, 3 insertions, 4 deletions

diff --git a/lib/PublicInbox/Msgmap.pm b/lib/PublicInbox/Msgmap.pm
index f15875e3..a8c874af 100644
--- a/lib/PublicInbox/Msgmap.pm
+++ b/lib/PublicInbox/Msgmap.pm
@@ -36,8 +36,7 @@ sub new_file {
                 create_tables($dbh);
                 $self->created_at(time) unless $self->created_at;
 
-                my $max = $self->max // 0;
-                $self->num_highwater($max);
+                $self->num_highwater(max($self));
                 $dbh->commit;
         }
         $self;
@@ -144,7 +143,7 @@ sub max {
         my $sth = $_[0]->{dbh}->prepare_cached('SELECT MAX(num) FROM msgmap',
                                                 undef, 1);
         $sth->execute;
-        $sth->fetchrow_array;
+        $sth->fetchrow_array // 0;
 }
 
 sub minmax {
@@ -153,7 +152,7 @@ sub minmax {
         my $sth = $_[0]->{dbh}->prepare_cached('SELECT MIN(num) FROM msgmap',
                                                 undef, 1);
         $sth->execute;
-        ($sth->fetchrow_array, max($_[0]));
+        ($sth->fetchrow_array // 0, max($_[0]));
 }
 
 sub mid_delete {