public function testToString()
{
$admin = new PostAdmin('sonata.post.admin.post', 'NewsBundle\\Entity\\Post', 'SonataNewsBundle:PostAdmin');
$s = new \stdClass();
$this->assertNotEmpty($admin->toString($s));
$s = new FooToString();
$this->assertSame('salut', $admin->toString($s));
// To string method is implemented, but returns null
$s = new FooToStringNull();
$this->assertNotEmpty($admin->toString($s));
$this->assertSame('', $admin->toString(false));
}