From bb32940d12df1cadcd94bb7b4a071044c837cc9b Mon Sep 17 00:00:00 2001
From: Shihao Zhong <zhong950419@gmail.com>
Date: Wed, 16 Sep 2026 21:56:17 -0400
Subject: [PATCH v7 4/4] Add a TAP test for per-index vacuum progress reporting

Use the injection point added by the previous commit to stop with a
known index in progress, and check that pg_stat_progress_vacuum names
that index and then moves on to the next one rather than carrying a
stale value over.
---
 src/test/modules/test_misc/meson.build        |  1 +
 .../test_misc/t/016_vacuum_progress.pl        | 69 +++++++++++++++++++
 2 files changed, 70 insertions(+)
 create mode 100644 src/test/modules/test_misc/t/016_vacuum_progress.pl

diff --git a/src/test/modules/test_misc/meson.build b/src/test/modules/test_misc/meson.build
index 5d81f5b13be..27b33a2c61e 100644
--- a/src/test/modules/test_misc/meson.build
+++ b/src/test/modules/test_misc/meson.build
@@ -24,6 +24,7 @@ tests += {
       't/013_temp_obj_multisession.pl',
       't/014_log_statement_max_length.pl',
       't/015_temp_schema_exit_deferrable.pl',
+      't/016_vacuum_progress.pl',
     ],
     # The injection points are cluster-wide, so disable installcheck
     'runningcheck': false,
diff --git a/src/test/modules/test_misc/t/016_vacuum_progress.pl b/src/test/modules/test_misc/t/016_vacuum_progress.pl
new file mode 100644
index 00000000000..525e7621afd
--- /dev/null
+++ b/src/test/modules/test_misc/t/016_vacuum_progress.pl
@@ -0,0 +1,69 @@
+# Copyright (c) 2026, PostgreSQL Global Development Group
+#
+# Check that pg_stat_progress_vacuum reports the index being vacuumed.
+
+use strict;
+use warnings FATAL => 'all';
+use PostgreSQL::Test::Cluster;
+use PostgreSQL::Test::Utils;
+use Test::More;
+
+if (($ENV{enable_injection_points} // 'no') ne 'yes')
+{
+	plan skip_all => 'Injection points not supported by this build';
+}
+
+my $node = PostgreSQL::Test::Cluster->new('vacprog');
+$node->init;
+$node->append_conf('postgresql.conf', 'autovacuum = off');
+$node->start;
+
+if (!$node->check_extension('injection_points'))
+{
+	plan skip_all => 'Extension injection_points not installed';
+}
+
+$node->safe_psql(
+	'postgres', qq{
+	CREATE EXTENSION injection_points;
+	CREATE TABLE vacprog (a int, b int);
+	INSERT INTO vacprog SELECT g, g FROM generate_series(1, 20000) g;
+	CREATE INDEX vacprog_a ON vacprog (a);
+	CREATE INDEX vacprog_b ON vacprog (b);
+	DELETE FROM vacprog WHERE a % 2 = 0;
+	SELECT injection_points_attach('vacuum-index-in-progress', 'wait');
+});
+
+# Stop inside the per index loop, with one index known to be in progress.
+my $vac = $node->background_psql('postgres');
+$vac->query_until(qr//, "VACUUM vacprog;\n");
+$node->wait_for_event('client backend', 'vacuum-index-in-progress');
+
+my $first = $node->safe_psql(
+	'postgres', q{
+	SELECT c.relname FROM pg_stat_progress_vacuum v
+	  JOIN pg_class c ON c.oid = v.current_index_relid
+	 WHERE v.relid = 'vacprog'::regclass});
+like($first, qr/^vacprog_[ab]$/, "reports the index being vacuumed, $first");
+
+$node->safe_psql('postgres',
+	"SELECT injection_points_wakeup('vacuum-index-in-progress');");
+
+# The other index must be reported in its turn. A value left over from the
+# first index would never satisfy this.
+ok( $node->poll_query_until(
+		'postgres', qq{
+		SELECT count(*) = 1 FROM pg_stat_progress_vacuum v
+		  JOIN pg_class c ON c.oid = v.current_index_relid
+		 WHERE v.relid = 'vacprog'::regclass AND c.relname <> '$first'}),
+	'reports the next index in turn');
+
+$node->safe_psql(
+	'postgres', q{
+	SELECT injection_points_detach('vacuum-index-in-progress');
+	SELECT injection_points_wakeup('vacuum-index-in-progress');
+});
+$vac->quit;
+$node->stop;
+
+done_testing();
-- 
2.37.1 (Apple Git-137.1)