commit 14d988c748f3e500c44d65e073c276e6d8af6156
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Date:   Wed Feb 14 15:21:35 2024 +0000

    wait_for_restart_lsn_calculation

diff --git a/src/test/perl/PostgreSQL/Test/Cluster.pm b/src/test/perl/PostgreSQL/Test/Cluster.pm
index e2e70d0dbf..21cf179db1 100644
--- a/src/test/perl/PostgreSQL/Test/Cluster.pm
+++ b/src/test/perl/PostgreSQL/Test/Cluster.pm
@@ -3174,6 +3174,28 @@ $SIG{TERM} = $SIG{INT} = sub {
 
 =pod
 
+=item $node->wait_for_restart_lsn_calculation(self, slot_name)
+
+Create logical replication slot on given standby
+
+=cut
+
+sub wait_for_restart_lsn_calculation
+{
+	my ($self, $slot_name) = @_;
+	my ($stdout, $stderr);
+
+	$self->poll_query_until(
+		'postgres', qq[
+		SELECT restart_lsn IS NOT NULL
+		FROM pg_catalog.pg_replication_slots WHERE slot_name = '$slot_name'
+	])
+	  or die
+	  "timed out waiting for logical slot to calculate its restart_lsn";
+}
+
+=pod
+
 =item $node->create_logical_slot_on_standby(self, primary, slot_name, dbname)
 
 Create logical replication slot on given standby
@@ -3203,13 +3225,7 @@ sub create_logical_slot_on_standby
 	# xl_running_xacts WAL record from the restart_lsn onwards. First wait
 	# until the slot restart_lsn is determined.
 
-	$self->poll_query_until(
-		'postgres', qq[
-		SELECT restart_lsn IS NOT NULL
-		FROM pg_catalog.pg_replication_slots WHERE slot_name = '$slot_name'
-	])
-	  or die
-	  "timed out waiting for logical slot to calculate its restart_lsn";
+	$self->wait_for_restart_lsn_calculation($slot_name);
 
 	# Then arrange for the xl_running_xacts record for which pg_recvlogical is
 	# waiting.
diff --git a/src/test/recovery/t/035_standby_logical_decoding.pl b/src/test/recovery/t/035_standby_logical_decoding.pl
index f7b7fc7f9e..85330720c5 100644
--- a/src/test/recovery/t/035_standby_logical_decoding.pl
+++ b/src/test/recovery/t/035_standby_logical_decoding.pl
@@ -465,12 +465,8 @@ $psql_subscriber{subscriber_stdin} .= "\n";
 
 $psql_subscriber{run}->pump_nb();
 
-# See corresponding create_logical_slot_on_standby() code.
-$node_standby->poll_query_until(
-	'postgres', qq[
-		SELECT restart_lsn IS NOT NULL
-		FROM pg_catalog.pg_replication_slots WHERE slot_name = 'tap_sub'
-	]) or die "timed out waiting for logical slot to calculate its restart_lsn";
+# Wait for restart_lsn calculation
+$node_standby->wait_for_restart_lsn_calculation('tap_sub');
 
 # Speed up the subscription creation
 $node_primary->safe_psql('postgres', "SELECT pg_log_standby_snapshot()");