TestFieldConstraint.php

<?php

namespace Drupal\field_test\Plugin\Validation\Constraint;

use Symfony\Component\Validator\Constraints\NotEqualTo;

/**
 * Checks if a value is not equal.
 *
 * @Constraint(
 *   id = "TestField",
 *   label = @Translation("Test Field", context = "Validation"),
 *   type = { "integer" }
 * )
 */
class TestFieldConstraint extends NotEqualTo {
    
    /**
     * {@inheritdoc}
     */
    public function getRequiredOptions() {
        return [
            'value',
        ];
    }
    
    /**
     * {@inheritdoc}
     */
    public function validatedBy() {
        return '\\Symfony\\Component\\Validator\\Constraints\\NotEqualToValidator';
    }

}