test of changing subselects tree

mysql-test/r/subselect.result

@@ -532,6 +532,15 @@ Note	1246	Select 2 was reduced during optimisation
 SELECT * FROM t WHERE id IN (SELECT 1 UNION SELECT 3);
 id
 1
+SELECT * FROM t WHERE id IN (SELECT 1+(select 1));
+id
+2
+EXPLAIN SELECT * FROM t WHERE id IN (SELECT 1+(select 1));
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t	ref	id	id	5	const	1	Using where; Using index
+3	SUBSELECT								No tables used
+Warnings:
+Note	1246	Select 2 was reduced during optimisation
 EXPLAIN SELECT * FROM t WHERE id IN (SELECT 1 UNION SELECT 3);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t	index	NULL	id	5	NULL	2	Using where; Using index

mysql-test/t/subselect.test

@@ -317,6 +317,8 @@ INSERT INTO t VALUES (1),(2);
 SELECT * FROM t WHERE id IN (SELECT 1);
 EXPLAIN SELECT * FROM t WHERE id IN (SELECT 1);
 SELECT * FROM t WHERE id IN (SELECT 1 UNION SELECT 3);
+SELECT * FROM t WHERE id IN (SELECT 1+(select 1));
+EXPLAIN SELECT * FROM t WHERE id IN (SELECT 1+(select 1));
 EXPLAIN SELECT * FROM t WHERE id IN (SELECT 1 UNION SELECT 3);
 SELECT * FROM t WHERE id IN (SELECT 5 UNION SELECT 3);
 SELECT * FROM t WHERE id IN (SELECT 5 UNION SELECT 2);