class BreakLockLink

class BreakLockLink extends RenderElement implements ContainerFactoryPluginInterface {
    
    /**
     * The date formatter.
     *
     * @var \Drupal\Core\Datetime\DateFormatterInterface
     */
    protected $dateFormatter;
    
    /**
     * The entity type manager.
     *
     * @var \Drupal\Core\Entity\EntityTypeManagerInterface
     */
    protected $entityTypeManager;
    
    /**
     * The renderer.
     *
     * @var \Drupal\Core\Render\RendererInterface
     */
    protected $renderer;
    
    /**
     * Constructs a new BreakLockLink.
     *
     * @param array $configuration
     *   A configuration array containing information about the plugin instance.
     * @param string $plugin_id
     *   The plugin ID for the plugin instance.
     * @param mixed $plugin_definition
     *   The plugin implementation definition.
     * @param \Drupal\Core\Datetime\DateFormatterInterface $date_formatter
     *   The date formatter.
     * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
     *   The entity type manager.
     * @param \Drupal\Core\Render\RendererInterface $renderer
     *   The renderer.
     */
    public function __construct(array $configuration, $plugin_id, $plugin_definition, DateFormatterInterface $date_formatter, EntityTypeManagerInterface $entity_type_manager, RendererInterface $renderer) {
        parent::__construct($configuration, $plugin_id, $plugin_definition);
        $this->dateFormatter = $date_formatter;
        $this->entityTypeManager = $entity_type_manager;
        $this->renderer = $renderer;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
        return new static($configuration, $plugin_id, $plugin_definition, $container->get('date.formatter'), $container->get('entity_type.manager'), $container->get('renderer'));
    }
    
    /**
     * {@inheritdoc}
     */
    public function getInfo() {
        return [
            '#pre_render' => [
                [
                    $this,
                    'preRenderLock',
                ],
            ],
        ];
    }
    
    /**
     * Pre-render callback: Renders a lock into #markup.
     *
     * @param array $element
     *   A structured array with the following keys:
     *   - #label: The label of the object that is locked.
     *   - #lock: The lock object.
     *   - #url: The URL object with the destination to the break lock form.
     *
     * @return array
     *   The passed-in element containing a rendered lock in '#markup'.
     */
    public function preRenderLock($element) {
        if (isset($element['#lock']) && isset($element['#label']) && isset($element['#url'])) {
            
            /** @var \Drupal\Core\TempStore\Lock $lock */
            $lock = $element['#lock'];
            $age = $this->dateFormatter
                ->formatTimeDiffSince($lock->getUpdated());
            $owner = $this->entityTypeManager
                ->getStorage('user')
                ->load($lock->getOwnerId());
            $username = [
                '#theme' => 'username',
                '#account' => $owner,
            ];
            $element['#markup'] = $this->t('This @label is being edited by user @user, and is therefore locked from editing by others. This lock is @age old. Click here to <a href=":url">break this lock</a>.', [
                '@label' => $element['#label'],
                '@user' => $this->renderer
                    ->render($username),
                '@age' => $age,
                ':url' => $element['#url']->toString(),
            ]);
        }
        return $element;
    }

}