From 4a2e64b44cf8ec22a264d8fa495432f535482fb4 Mon Sep 17 00:00:00 2001
From: Maxim Orlov <orlovmg@gmail.com>
Date: Fri, 27 Dec 2024 19:39:58 +0300
Subject: [PATCH v13 6/7] TEST: try to replicate buggy oldest offset

---
 src/bin/pg_upgrade/t/005_offset.pl | 59 ++++++++++++++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/src/bin/pg_upgrade/t/005_offset.pl b/src/bin/pg_upgrade/t/005_offset.pl
index df84186de4..2d91d101fa 100644
--- a/src/bin/pg_upgrade/t/005_offset.pl
+++ b/src/bin/pg_upgrade/t/005_offset.pl
@@ -305,6 +305,8 @@ my @TESTS = (
 	100, 101, 102, 103, 104, 105, 106,
 	# self upgrade
 	1000,
+	# buggy
+	2000
 );
 
 # =============================================================================
@@ -560,4 +562,61 @@ SKIP:
 	ok(1, "TEST $TEST_NO PASSED");
 }
 
+# =============================================================================
+# Buggy
+# =============================================================================
+
+SKIP:
+{
+	my $TEST_NO = 2000;
+	skip "do not test case $TEST_NO", 1
+		unless ( grep( /^$TEST_NO$/, @TESTS ) );
+
+	if (!defined($ENV{oldinstall}))
+	{
+		die "oldinstall is not defined";
+	}
+
+	my $dbname = 'buggy';
+	my $newnode = PostgreSQL::Test::Cluster->new("new_$dbname");
+	my $oldnode = PostgreSQL::Test::Cluster->new("old_$dbname",
+					install_path => $ENV{oldinstall});
+	$newnode->init;
+	$oldnode->init(force_initdb => 1);
+
+	$oldnode->append_conf('postgresql.conf', q(
+		autovacuum = off
+		max_prepared_transactions = 2
+		fsync = off
+	));
+	$oldnode->start;
+
+	mxid_gen2($oldnode, 'FOO', 1.25);
+	mxid_gen2($oldnode, 'BAR', 1.25);
+
+	$oldnode->safe_psql('postgres', q(
+		DROP TABLE BAR;
+		CHECKPOINT;
+	));
+	$oldnode->stop;
+
+	unlink($oldnode->data_dir . "/pg_multixact/offsets/0000");
+
+	command_ok(
+		[
+			'pg_upgrade', '--no-sync',
+			'-d', $oldnode->data_dir,
+			'-D', $newnode->data_dir,
+			'-b', $oldnode->config_data('--bindir'),
+			'-B', $newnode->config_data('--bindir'),
+			'-s', $newnode->host,
+			'-p', $oldnode->port,
+			'-P', $newnode->port,
+			'--copy'
+		],
+		'run of pg_upgrade');
+
+	ok(1, "TEST $TEST_NO PASSED");
+}
+
 done_testing();
-- 
2.43.0