Bug#19671 mysql_list_fields returns incorrect table name for VIEWs

After view onening real view db name and table name are placed
into table_list->view_db & table_list->view_name.
Item_field class does not handle these names properly during 
intialization of Send_field.
The fix is to use new class 'Item_ident_for_show' 
which sets correct view db name and table name for Send_field.


sql/item.cc:
  Bug#19671 mysql_list_fields returns incorrect table name for VIEWs
  new Item_ident_for_show class which correctly sets view db and table names
  for Send_field.
sql/item.h:
  Bug#19671 mysql_list_fields returns incorrect table name for VIEWs
  new Item_ident_for_show class which correctly sets view db and table names
  for Send_field.
sql/sql_show.cc:
  Bug#19671 mysql_list_fields returns incorrect table name for VIEWs
  new Item_ident_for_show is used for views
tests/mysql_client_test.c:
  Bug#19671 mysql_list_fields returns incorrect table name for VIEWs
  test case

1 files changed, 22 insertions, 0 deletions

diff --git a/sql/item.h b/sql/item.h
index 2cadfda6895..bee24d23245 100644
--- a/sql/item.h
+++ b/sql/item.h
@@ -1142,6 +1142,28 @@ public:
                             bool any_privileges);
 };
 
+
+class Item_ident_for_show :public Item
+{
+public:
+  Field *field;
+  const char *db_name;
+  const char *table_name;
+
+  Item_ident_for_show(Field *par_field, const char *db_arg,
+                      const char *table_name_arg)
+    :field(par_field), db_name(db_arg), table_name(table_name_arg)
+  {}
+
+  enum Type type() const { return FIELD_ITEM; }
+  double val_real() { return field->val_real(); }
+  longlong val_int() { return field->val_int(); }
+  String *val_str(String *str) { return field->val_str(str); }
+  my_decimal *val_decimal(my_decimal *dec) { return field->val_decimal(dec); }
+  void make_field(Send_field *tmp_field);
+};
+
+
 class Item_equal;
 class COND_EQUAL;