ValidSequenceKeysConstraintValidator.php

<?php

declare (strict_types=1);
namespace Drupal\Core\Validation\Plugin\Validation\Constraint;

use Drupal\Core\DependencyInjection\AutowireTrait;
use Drupal\Core\DependencyInjection\ClassResolverInterface;
use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
use Drupal\Core\Validation\ConstraintValidatorFactory;
use Symfony\Component\Validator\Constraint;
use Symfony\Component\Validator\ConstraintValidator;
use Symfony\Component\Validator\Exception\UnexpectedTypeException;

/**
 * Validates that all the keys of a sequence match the specified constraints.
 */
class ValidSequenceKeysConstraintValidator extends ConstraintValidator implements ContainerInjectionInterface {
  use AutowireTrait;
  public function __construct(private readonly ClassResolverInterface $classResolver) {
  }
  
  /**
   * {@inheritdoc}
   */
  public function validate(mixed $value, Constraint $constraint) : void {
    assert($constraint instanceof ValidSequenceKeysConstraint);
    if (!is_array($value)) {
      throw new UnexpectedTypeException($value, 'array');
    }
    if (empty($value)) {
      return;
    }
    $previousViolationCount = count($this->context
      ->getViolations());
    $constraintValidatorFactory = new ConstraintValidatorFactory($this->classResolver);
    foreach (array_keys($value) as $sequence_key) {
      foreach ($constraint->constraints as $item) {
        $validator = $constraintValidatorFactory->getInstance($item);
        $validator->initialize($this->context);
        $validator->validate($sequence_key, $item);
      }
    }
    if (count($this->context
      ->getViolations()) > $previousViolationCount) {
      $this->context
        ->buildViolation($constraint->message)
        ->addViolation();
    }
  }

}