Tighten test in contrib/bloom/t/001_wal.pl.

Make bloom WAL test compare psql output text, not just result codes;
this was evidently the intent all along, but it was mis-coded.
In passing, make sure we will notice any failure in setup steps.

Alexander Korotkov, reviewed by Michael Paquier and Masahiko Sawada

Discussion: https://postgr.es/m/CAPpHfdtohPdQ9rc5mdWjxq+3VsBNw534KV_5O65dTQrSdVJNgw@mail.gmail.com

contrib/bloom/t/001_wal.pl

@@ -32,8 +32,8 @@ SELECT * FROM tst WHERE i = 7 AND t = 'e';
 );
 
 	# Run test queries and compare their result
-	my $master_result = $node_master->psql("postgres", $queries);
-	my $standby_result = $node_standby->psql("postgres", $queries);
+	my $master_result = $node_master->safe_psql("postgres", $queries);
+	my $standby_result = $node_standby->safe_psql("postgres", $queries);
 
 	is($master_result, $standby_result, "$test_name: query result matches");
 }
@@ -54,12 +54,12 @@ $node_standby->init_from_backup($node_master, $backup_name,
 $node_standby->start;
 
 # Create some bloom index on master
-$node_master->psql("postgres", "CREATE EXTENSION bloom;");
-$node_master->psql("postgres", "CREATE TABLE tst (i int4, t text);");
-$node_master->psql("postgres",
+$node_master->safe_psql("postgres", "CREATE EXTENSION bloom;");
+$node_master->safe_psql("postgres", "CREATE TABLE tst (i int4, t text);");
+$node_master->safe_psql("postgres",
 "INSERT INTO tst SELECT i%10, substr(md5(i::text), 1, 1) FROM generate_series(1,100000) i;"
 );
-$node_master->psql("postgres",
+$node_master->safe_psql("postgres",
 	"CREATE INDEX bloomidx ON tst USING bloom (i, t) WITH (col1 = 3);");
 
 # Test that queries give same result
@@ -68,12 +68,12 @@ test_index_replay('initial');
 # Run 10 cycles of table modification. Run test queries after each modification.
 for my $i (1 .. 10)
 {
-	$node_master->psql("postgres", "DELETE FROM tst WHERE i = $i;");
+	$node_master->safe_psql("postgres", "DELETE FROM tst WHERE i = $i;");
 	test_index_replay("delete $i");
-	$node_master->psql("postgres", "VACUUM tst;");
+	$node_master->safe_psql("postgres", "VACUUM tst;");
 	test_index_replay("vacuum $i");
 	my ($start, $end) = (100001 + ($i - 1) * 10000, 100000 + $i * 10000);
-	$node_master->psql("postgres",
+	$node_master->safe_psql("postgres",
 "INSERT INTO tst SELECT i%10, substr(md5(i::text), 1, 1) FROM generate_series($start,$end) i;"
 	);
 	test_index_replay("insert $i");