fixed problem in resolving items of outer query in subqueries in view (BUG#6394)

mysql-test/r/view.result:
  Resolving view fields in subqueries in VIEW
mysql-test/t/view.test:
  Resolving view fields in subqueries in VIEW
sql/table.cc:
  emulation of main table list by ancestor list added to view preparation routine  to allow subqueries resolve item from outer query corectly

mysql-test/r/view.result

@@ -1724,3 +1724,23 @@ a	b
 301	0
 drop view v3;
 drop tables t1,t2;
+create table t1(c1 int);
+create table t2(c2 int);
+insert into t1 values (1),(2),(3);
+insert into t2 values (1);
+SELECT c1 FROM t1 WHERE c1 IN (SELECT c2 FROM t2);
+c1
+1
+SELECT c1 FROM t1 WHERE EXISTS (SELECT c2 FROM t2 WHERE c2 = c1);
+c1
+1
+create view v1 as SELECT c1 FROM t1 WHERE c1 IN (SELECT c2 FROM t2);
+create view v2 as SELECT c1 FROM t1 WHERE EXISTS (SELECT c2 FROM t2 WHERE c2 = c1);
+select * from v1;
+c1
+1
+select * from v2;
+c1
+1
+drop view v2, v1;
+drop table t1, t2;

mysql-test/t/view.test

@@ -1654,3 +1654,19 @@ select * from v3;
 
 drop view v3;
 drop tables t1,t2;
+
+#
+# Resolving view fields in subqueries in VIEW (Bug #6394)
+#
+create table t1(c1 int);
+create table t2(c2 int);
+insert into t1 values (1),(2),(3);
+insert into t2 values (1);
+SELECT c1 FROM t1 WHERE c1 IN (SELECT c2 FROM t2);
+SELECT c1 FROM t1 WHERE EXISTS (SELECT c2 FROM t2 WHERE c2 = c1);
+create view v1 as SELECT c1 FROM t1 WHERE c1 IN (SELECT c2 FROM t2);
+create view v2 as SELECT c1 FROM t1 WHERE EXISTS (SELECT c2 FROM t2 WHERE c2 = c1);
+select * from v1;
+select * from v2;
+drop view v2, v1;
+drop table t1, t2;

sql/table.cc

@@ -1687,6 +1687,7 @@ bool st_table_list::setup_ancestor(THD *thd, Item **conds,
   Field_translator *transl;
   SELECT_LEX *select= &view->select_lex;
   SELECT_LEX *current_select_save= thd->lex->current_select;
+  byte *main_table_list_save= thd->lex->select_lex.table_list.first;
   Item *item;
   TABLE_LIST *tbl;
   List_iterator_fast<Item> it(select->item_list);
@@ -1709,8 +1710,13 @@ bool st_table_list::setup_ancestor(THD *thd, Item **conds,
   if (field_translation)
   {
     DBUG_PRINT("info", ("there are already translation table"));
-    /* prevent look up in SELECTs tree */
+    /*
+      prevent look up in SELECTs tree, and emulate main table list by
+      ancestor table list for subquery processing
+    */
     thd->lex->current_select= &thd->lex->select_lex;
+    thd->lex->select_lex.table_list.first= (byte *)ancestor;
+
     thd->lex->select_lex.no_wrap_view_item= 1;
     thd->set_query_id= 1;
     /* this view was prepared already on previous PS/SP execution */
@@ -1755,8 +1761,13 @@ bool st_table_list::setup_ancestor(THD *thd, Item **conds,
     DBUG_RETURN(1);
   }
 
-  /* prevent look up in SELECTs tree */
+  /*
+    prevent look up in SELECTs tree, and emulate main table list by ancestor
+    table list for subquery processing
+  */
   thd->lex->current_select= &thd->lex->select_lex;
+  thd->lex->select_lex.table_list.first= (byte *)ancestor;
+
   thd->lex->select_lex.no_wrap_view_item= 1;
 
   /*
@@ -1901,6 +1912,7 @@ bool st_table_list::setup_ancestor(THD *thd, Item **conds,
 ok:
   thd->lex->select_lex.no_wrap_view_item= save_wrapper;
   thd->lex->current_select= current_select_save;
+  thd->lex->select_lex.table_list.first= main_table_list_save;
   thd->set_query_id= save_set_query_id;
   thd->allow_sum_func= save_allow_sum_func;
   DBUG_RETURN(0);
@@ -1915,6 +1927,7 @@ err:
   }
   thd->lex->select_lex.no_wrap_view_item= save_wrapper;
   thd->lex->current_select= current_select_save;
+  thd->lex->select_lex.table_list.first= main_table_list_save;
   thd->set_query_id= save_set_query_id;
   thd->allow_sum_func= save_allow_sum_func;
   DBUG_RETURN(1);