mariadb/mysql-test/main/mysql_upgrade-6984.test

#
# MDEV-6984 Can't migrate from MySQL 5.6.21 to MariaDB 10
#
--source include/not_embedded.inc

#
# When 'root' account is password protected and MYSQL_UPGRADE doesn't
# know the password (meaning, MYSQL_UPGRADE is run automatically
# on upgrade), MYSQLD has to be started with --skip-grant-tables.
#
# In this setup MYSQL_UPGRADE cannot continue after issuing FLUSH PRIVILEGES
#

update mysql.global_priv set priv=json_set(priv, '$.plugin', 'mysql_native_password', '$.authentication_string', password('foo'));

--exec $MYSQL_UPGRADE

connect(con1,localhost,root,foo,,,);

update mysql.global_priv set priv=json_compact(json_remove(priv, '$.plugin', '$.authentication_string'));
flush privileges;
# Load event table
set global event_scheduler=OFF;