How to validate an array which can be empty

My class, which I try to validate, has a property, which can be either an empty array or an array of certain objects:

use App\Api\Dto\WorkHour as WorkHourDto;
use Symfony\Component\Serializer\Annotation\Groups as SerializerGroups;
use Symfony\Component\Validator\Constraints as Assert;

[....]

        #[Assert\All(
            new Assert\Type(type: WorkHourDto::class)
        )]
        #[Assert\Valid(groups: ['create', 'update'])]
        #[SerializerGroups(['view', 'create', 'update'])]
        public array $workHours = []
[....]

What would be the correct way to assert this? Currently the validation fails if the array is empty.

I have seen then When Constraint [https://symfony.com/doc/6.4/reference/constraints/When.html], but it seems that it is only for checking complex details.

Of course I can leave out the validation at all or only assert that it is an array, but that would be my last resort.

I am running symfony 6.4 on php8.2

Wrap it into Assert\AtLeastOneOf

    #[
        Assert\AtLeastOneOf([
            new Assert\Count(max: 0),
            new Assert\All(
                new Assert\Type(type: WorkHourDto::class)
            ),
        ]),
        Assert\Valid(groups: ['create', 'update']),
        SerializerGroups(['view', 'create', 'update']),
    ]
    public array $workHours = [],

PHP-only approach would be to have setter:

    private array $workHours = [];

    public function setWorkHours(WorkHourDto ...$workHours) {
        $this->workHours = $workHours;
    }