<?php

        $merchant = MerchantQuery::create()->findPk(1);
        $aclProvider = $this->get('security.acl.provider');

        // no ACL set at all!

        $objectIdentity = ObjectIdentity::fromDomainObject($merchant);
        $securityIdentity = UserSecurityIdentity::fromAccount($securityContext->getToken()->getUser());
        // $securityIdentity = new RoleSecurityIdentity('ROLE_USER');

        try {
            $acl = $aclProvider->findAcl($objectIdentity, array($securityIdentity));
        } catch (AclNotFoundException $e) {
            $acl = $aclProvider->createAcl($objectIdentity);
        }

        if (!$acl->isSidLoaded($securityIdentity)) {
            $acl->insertObjectAce($securityIdentity, MaskBuilder::MASK_VIEW);
            $aclProvider->updateAcl($acl);
        }

        var_dump($securityContext->isGranted('VIEW', $merchant)); // FALSE