From 23172b798c82b039ec5be178a3740362ae65fc37 Mon Sep 17 00:00:00 2001
From: Sergey Fukanchik <s.fukanchik@postgrespro.ru>
Date: Sun, 7 Sep 2025 12:06:27 +0300
Subject: [PATCH v2 2/2] Add a TAP test for oversized WAL records

---
 .../recovery/t/049_oversized_wal_record.pl    | 50 +++++++++++++++++++
 1 file changed, 50 insertions(+)
 create mode 100644 src/test/recovery/t/049_oversized_wal_record.pl

diff --git a/src/test/recovery/t/049_oversized_wal_record.pl b/src/test/recovery/t/049_oversized_wal_record.pl
new file mode 100644
index 00000000000..8604ef53d48
--- /dev/null
+++ b/src/test/recovery/t/049_oversized_wal_record.pl
@@ -0,0 +1,50 @@
+
+# Copyright (c) 2025, PostgreSQL Global Development Group
+
+# Try to create a WAL record which is larger than the limit XLogRecordMaxSize.
+# That should raise an error.
+
+use strict;
+use warnings FATAL => 'all';
+use PostgreSQL::Test::Cluster;
+use Test::More;
+
+# Disable the test unless requested explicitly because it requires 1Gb of memory
+if (exists $ENV{PG_TEST_EXTRA}
+	&& $ENV{PG_TEST_EXTRA} =~ m/\boversized_wal_record\b/)
+{
+	plan tests => 4;
+}
+else
+{
+	plan skip_all =>
+      'Skipping oversized_wal_record test as it requires a lot of memory';
+}
+
+note "Check handing of oversized WAL records";
+
+# Initialize and start basic node
+my $node = PostgreSQL::Test::Cluster->new('node');
+
+$node->init;
+
+$node->start;
+
+# Insert oversized record
+my ($ret, $stdout, $stderr) = $node->psql(
+	'postgres',
+	"select pg_logical_emit_message(false, 'a', repeat('00000000', (1020 * 1024 * 1024)/8+1), true)",
+	on_error_die => 0
+  );
+
+# Verify we have error
+ok($ret != 0, 'exit code is non-zero');
+
+ok($stderr =~ qr/ERROR:  oversized WAL record/, 'expect error');
+
+ok($stderr =~ qr/DETAIL:  WAL record would be [0-9]+ bytes \(of maximum [0-9]+ bytes\);/,
+   'error details');
+
+$node->stop;
+
+done_testing();
-- 
2.34.1