private function createGroups(OutputInterface $output)
    {
        $em = $this->container->get('ekyna_user.group.manager');
        $repository = $this->container->get('ekyna_user.group.repository');

        foreach ($this->defaultGroups as $name => $options) {
            $output->write(sprintf(
                '- <comment>%s</comment> %s ',
                $name,
                str_pad('.', 44 - mb_strlen($name), '.', STR_PAD_LEFT)
            ));
            if (null !== $group = $repository->findOneBy(['name' => $name])) {
                $output->writeln('already exists.');
                continue;
            }
            /** @var \Ekyna\Bundle\UserBundle\Model\GroupInterface $group */
            $group = $repository->createNew();
            $group
                ->setDefault($options[2])
                ->setName($name)
                ->setRoles($options[0])
            ;
            $em->persist($group);
            $output->writeln('created.');
        }
        $em->flush();
    }