1.php
<?php
require '2.php';
require '3.php';

xdebug_start_code_coverage(XDEBUG_CC_UNUSED | XDEBUG_CC_DEAD_CODE | XDEBUG_CC_BRANCH_CHECK);

$bar = 'bar';

$class = new Baz();
$class->baz();

print_r(xdebug_get_code_coverage());

2.php
<?php

$foo = 'bar';

3.php
<?php

class Baz
{

public function baz()
{
    $foo = 'baz';
}

}