I have encourred a strange problem when use a Symfony validator, the constraints violations is always empty even if entity does not respect constraints.

Entity :

```
use Symfony\Component\Validator\Constraints as Assert;

class Author
{
  /**
  * @Assert\NotBlank()
  */
  public $name;
}

```

The code to use validator :

```
$Author = new Author();

$validator = Validation::createValidator();
var_dump( count($validator-> validate($Author)) );

```

Result : 0

Do you have an idea on the origin of this problem ?

Thanks in advance.

Jérémy