/usr/lib/mysql-testsuite/include/have_lowercase2.inc is in percona-server-test-5.6 5.6.22-rel71.0-0ubuntu4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 | --require r/lowercase2.require
--disable_query_log
show variables like 'lower_case_table_names';
--enable_query_log
|