v2writable: count_shards: allow working without {ibx}

This will be needed for ExtSearchIdx which doesn't have a
persistent PublicInbox::Inbox object.

1 files changed, 7 insertions, 5 deletions

diff --git a/lib/PublicInbox/V2Writable.pm b/lib/PublicInbox/V2Writable.pm
index f575ba11..667a11f8 100644
--- a/lib/PublicInbox/V2Writable.pm
+++ b/lib/PublicInbox/V2Writable.pm
@@ -65,11 +65,13 @@ sub nproc_shards ($) {
 
 sub count_shards ($) {
         my ($self) = @_;
-        # always load existing shards in case core count changes:
-        # Also, shard count may change while -watch is running
-        my $srch = $self->{ibx}->search or return 0;
-        delete $self->{ibx}->{search};
-        $srch->{nshard} // 0
+        $self->{ibx} ? do {
+                # always load existing shards in case core count changes:
+                # Also, shard count may change while -watch is running
+                my $srch = $self->{ibx}->search or return 0;
+                delete $self->{ibx}->{search};
+                $srch->{nshard} // 0
+        } : $self->{nshard}; # self->{nshard} is for ExtSearchIdx
 }
 
 sub new {