How do I setup mysql sandbox for Test::DBIX::Class?

Question

I'm trying to setup Test::DBIX::Class with MySQL::Sandbox. But it looks like my setup is not correct because the warning message:

Test-DBIx-Class-0.52$ mysql_install_db=$HOME/opt/sandbox/mysql/5.5.54/bin/mysqld BASE_DIR=/tmp/sandboxes/msb_5_5_54 prove -l t/08-test-mysqld.t 
t/08-test-mysqld.t .. mysqld: Can't change dir to '/var/lib/mysql/' (Errcode: 13 - Permission denied)
t/08-test-mysqld.t .. ok   
All tests successful.
Files=1, Tests=7, 28 wallclock secs ( 0.02 usr  0.00 sys +  1.05 cusr  0.57 csys =  1.64 CPU)
Result: PASS

/var/lib/mysql/ is not a part of my mysql sandbox setup. What's the reason for the warning message?

I'm using 08-test-mysqld.t for testing purpose.

My mysql sanbox setup:

$all_info = {
              '5554' => {
                          'opt' => {
                                     'datadir' => $HOME.'/sandboxes/msb_5_5_54/data',
                                     'log_error' => 'msandbox.err',
                                     'socket' => '/tmp/mysql_sandbox5554.sock',
                                     'prompt' => '\'mysql [\\h] {\\u} (\\d) > \'',
                                     'bind_address' => '127.0.0.1',
                                     'tmpdir' => $HOME.'/sandboxes/msb_5_5_54/tmp',
                                     'user' => 'me',
                                     'lower_case_table_names' => '0',
                                     'basedir' => $HOME.'/opt/sandbox/mysql/5.5.54',
                                     'port' => '5554',
                                     'pid_file' => $HOME.'/sandboxes/msb_5_5_54/data/mysql_sandbox5554.pid',
                                     'password' => 'msandbox'
                                   },
                          'conf' => undef
                        }
            };

Answer 1

The warning message is generated in Test::mysqld::_use_mysqld_initialize and could be ignored. After setting MYSQL_INSTALL_DB it works fine:

Here my current test setting:

export SB_DIR=$HOME/opt/sandbox/mysql/5.5.54
Test-DBIx-Class-0.52$ MYSQLD=$SB_DIR/bin/mysqld \
MYSQL_INSTALL_DB=$SB_DIR/scripts/mysql_install_db \
KEEP_DB=1 \
prove -lv t/08-test-mysqld.t

KEEP_DB is helpfull for diagnostic purposes.