MDEV-30082 View definition losing brackets changes semantics of the query and causes wrong result

Item_func_not_all::print() either uses Item_func::print() or directly invokes args[0]->print(). Thus the precedence should be either the one of Item_func or of args[0]. Item_allany_subselect::print() prints args[0], then a comparison op, then a subquery. That is, the precedence should be the one of a comparison.

Author: vuvova

mysql-test/main/precedence_bugs.result

@@ -58,3 +58,21 @@ Create View	CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY D
 character_set_client	latin1
 collation_connection	latin1_swedish_ci
 drop view v1;
+#
+# MDEV-30082 View definition losing brackets changes semantics of the query and causes wrong result
+#
+create table t1 (a varchar(1), b bool) engine=myisam;
+insert into t1 values ('u',1),('s',1);
+select * from t1 where t1.b in (t1.a <= all (select 'a'));
+a	b
+create view v as select * from t1 where t1.b in (t1.a <= all (select 'a'));
+select * from v;
+a	b
+show create view v;
+View	Create View	character_set_client	collation_connection
+v	CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `v` AS select `t1`.`a` AS `a`,`t1`.`b` AS `b` from `t1` where `t1`.`b` = (`t1`.`a` <= all (select 'a'))	latin1	latin1_swedish_ci
+drop view v;
+drop table t1;
+#
+# End of 10.3 results
+#

mysql-test/main/precedence_bugs.test

@@ -39,3 +39,19 @@ drop table t1;
 create view v1 as select 1 like (now() between '2000-01-01' and '2012-12-12' );
 query_vertical show create view v1;
 drop view v1;
+
+--echo #
+--echo # MDEV-30082 View definition losing brackets changes semantics of the query and causes wrong result
+--echo #
+create table t1 (a varchar(1), b bool) engine=myisam;
+insert into t1 values ('u',1),('s',1);
+select * from t1 where t1.b in (t1.a <= all (select 'a'));
+create view v as select * from t1 where t1.b in (t1.a <= all (select 'a'));
+select * from v;
+show create view v;
+drop view v;
+drop table t1;
+
+--echo #
+--echo # End of 10.3 results
+--echo #

sql/item_cmpfunc.h

@@ -668,6 +668,8 @@ class Item_func_not_all :public Item_func_not
  longlong val_int();
  enum Functype functype() const { return NOT_ALL_FUNC; }
  const char *func_name() const { return "<not>"; }
+ enum precedence precedence() const
+ { return show ? Item_func::precedence() : args[0]->precedence(); }
  bool fix_fields(THD *thd, Item **ref)
  {return Item_func::fix_fields(thd, ref);}
  virtual void print(String *str, enum_query_type query_type);

sql/item_subselect.h

@@ -783,6 +783,7 @@ class Item_allany_subselect :public Item_in_subselect
  bool select_transformer(JOIN *join);
  void create_comp_func(bool invert) { func= func_creator(invert); }
  void print(String *str, enum_query_type query_type);
+ enum precedence precedence() const { return CMP_PRECEDENCE; }
  bool is_maxmin_applicable(JOIN *join);
  bool transform_into_max_min(JOIN *join);
  void no_rows_in_result();