[Phpmyadmin-devel] How to write unit test cases for DBI class?

Hi all, I am writing unit test cases for DBI classes. in the code base: [1], including DBI class: * DBIMysql.class.php * DBIMysqli.class.php But I have no idea how to test them. two methods: 1. Mock built-in PHP DB client API ( ig: mysql_connect) they call PHP DB client API finally, but I don't know how I can mock this kind of built-in functions 2. DB real operations If try to test with real data, I think It is not accessible, because I need to connect to DB with username and password. so I think method 1 is more flexible, Can someone give me some advice? thanks [1] https://github.com/phpmyadmin/phpmyadmin/tree/master/libraries/dbi Adam