<?php

/*
 * This file is part of the Sylius package.
 *
 * (c) Paweł Jędrzejewski
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Sylius\Component\Core\Promotion\Checker\Rule;

use Sylius\Component\Core\Model\CustomerInterface;
use Sylius\Component\Core\Model\OrderInterface;
use Sylius\Component\Promotion\Checker\Rule\RuleCheckerInterface;
use Sylius\Component\Promotion\Exception\UnsupportedTypeException;
use Sylius\Component\Promotion\Model\PromotionSubjectInterface;

/**
 * @author Antonio Perić <antonio@locastic.com>
 */
class CustomerGroupRuleChecker implements RuleCheckerInterface
{
    /**
     * {@inheritdoc}
     */
    public function isEligible(PromotionSubjectInterface $subject, array $configuration)
    {
        if (!$subject instanceof OrderInterface) {
            throw new UnsupportedTypeException($subject, OrderInterface::class);
        }

        if (null === $customer = $subject->getCustomer()) {
            return false;
        }

        if (!$customer instanceof CustomerInterface) {
            return false;
        }

        if ($configuration['groups'] === $customer->getGroup()->getId()) {
            return true;
        }

        return false;
    }

    /**
     * {@inheritdoc}
     */
    public function getConfigurationFormType()
    {
        return 'sylius_promotion_rule_customer_group_configuration';
    }
}

<?php

/*
 * This file is part of the Sylius package.
 *
 * (c) Paweł Jędrzejewski
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Sylius\Component\Core\Promotion\Checker\Rule;

use Sylius\Component\Core\Model\CustomerInterface;
use Sylius\Component\Core\Model\OrderInterface;
use Sylius\Component\Promotion\Checker\Rule\RuleCheckerInterface;
use Sylius\Component\Promotion\Exception\UnsupportedTypeException;
use Sylius\Component\Promotion\Model\PromotionSubjectInterface;

/**
 * @author Antonio Perić <antonio@locastic.com>
 */
class CustomerGroupRuleChecker implements RuleCheckerInterface
{
    /**
     * {@inheritdoc}
     */
    public function isEligible(PromotionSubjectInterface $subject, array $configuration)
    {
        if (!$subject instanceof OrderInterface) {
            throw new UnsupportedTypeException($subject, OrderInterface::class);
        }

        if (null === $customer = $subject->getCustomer()) {
            return false;
        }

        if (!$customer instanceof CustomerInterface) {
            return false;
        }

        if (is_null($customer->getGroup())) {
            return false;
        }

        if ($configuration['group'] === $customer->getGroup()->getId()) {
            return true;
        }

        return false;
    }

    /**
     * {@inheritdoc}
     */
    public function getConfigurationFormType()
    {
        return 'sylius_promotion_rule_customer_group_configuration';
    }
}

Fix Customer Group Type and RuleChecker
Fix Customer Group Type and RuleChecker
