From 9853edb792f81953567b68da0b79baa57a8c518c Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horikyoga.ntt@gmail.com>
Date: Wed, 9 Dec 2020 17:21:49 +0900
Subject: [PATCH v2 1/2] Add a new test to detect a replication bug

---
 src/test/recovery/t/001_stream_rep.pl | 65 ++++++++++++++++++++++++++-
 1 file changed, 64 insertions(+), 1 deletion(-)

diff --git a/src/test/recovery/t/001_stream_rep.pl b/src/test/recovery/t/001_stream_rep.pl
index 9e31a53de7..13b6e00da4 100644
--- a/src/test/recovery/t/001_stream_rep.pl
+++ b/src/test/recovery/t/001_stream_rep.pl
@@ -2,8 +2,9 @@
 use strict;
 use warnings;
 use PostgresNode;
+use Time::HiRes qw(usleep);
 use TestLib;
-use Test::More tests => 36;
+use Test::More tests => 37;
 
 # Initialize primary node
 my $node_primary = get_new_node('primary');
@@ -409,3 +410,65 @@ ok( ($phys_restart_lsn_pre cmp $phys_restart_lsn_post) == 0,
 my $primary_data = $node_primary->data_dir;
 ok(!-f "$primary_data/pg_wal/$segment_removed",
 	"WAL segment $segment_removed recycled after physical slot advancing");
+
+#
+# Check if timeline-increment works while reading a historic timeline.
+my $node_primary_2 = get_new_node('primary_2');
+$node_primary_2->init(allows_streaming => 1);
+$node_primary_2->enable_archiving; # needed to make .paritial segment
+$node_primary_2->start;
+$node_primary_2->backup($backup_name);
+my $node_standby_3 = get_new_node('standby_3');
+$node_standby_3->init_from_backup($node_primary_2, $backup_name,
+								  has_streaming => 1);
+$node_primary_2->stop;
+$node_primary_2->set_standby_mode; # increment primary timeline
+$node_primary_2->start;
+$node_primary_2->promote;
+my $logstart = get_log_size($node_standby_3);
+$node_standby_3->start;
+
+my $success = 0;
+for (my $i = 0 ; $i < 1000; $i++)
+{
+	if (find_in_log(
+			$node_standby_3,
+			"requested WAL segment [0-9A-F]+ has already been removed",
+			$logstart))
+	{
+		last;
+	}
+	elsif (find_in_log(
+			$node_standby_3,
+			"End of WAL reached on timeline",
+			   $logstart))
+	{
+		$success = 1;
+		last;
+	}
+	usleep(100_000);
+}
+
+ok($success, 'Timeline increment while reading a historic timeline');
+
+# return the size of logfile of $node in bytes
+sub get_log_size
+{
+	my ($node) = @_;
+
+	return (stat $node->logfile)[7];
+}
+
+# find $pat in logfile of $node after $off-th byte
+sub find_in_log
+{
+	my ($node, $pat, $off) = @_;
+
+	$off = 0 unless defined $off;
+	my $log = TestLib::slurp_file($node->logfile);
+	return 0 if (length($log) <= $off);
+
+	$log = substr($log, $off);
+
+	return $log =~ m/$pat/;
+}
-- 
2.27.0