DateTimeValidator example

namespace Symfony\Component\Validator\Tests\Constraints;

use Symfony\Component\Validator\Constraints\DateTime;
use Symfony\Component\Validator\Constraints\DateTimeValidator;
use Symfony\Component\Validator\Exception\UnexpectedValueException;
use Symfony\Component\Validator\Test\ConstraintValidatorTestCase;

class DateTimeValidatorTest extends ConstraintValidatorTestCase
{
    protected function createValidator(): DateTimeValidator
    {
        return new DateTimeValidator();
    }

    public function testNullIsValid()
    {
        $this->validator->validate(null, new DateTime());

        $this->assertNoViolation();
    }

    public function testEmptyStringIsValid()
    {