how does Bar call test() on Foo if its defined as protected?

protected.php

<?php

abstract class Base {
    protected static function test() {
        echo get_called_class()."\n";
    }
}

class Foo extends Base {
    protected static function test2(){
        echo get_called_class()."\n";
    }
}

class Bar extends Base {
    public static function fooTest() {
        echo Foo::test()."\n";
    }

    public static function fooTest2() {
        echo Foo::test2()."\n";
    }
}

Bar::fooTest(); // Foo
Bar::fooTest2(); // Fatal call to protected method Foo::test2() from context 'Bar'