Pimcore\Model\Object\Service::mergeFieldDefinition PHP Method

    private static function mergeFieldDefinition(&$mergedFieldDefinition, &$customFieldDefinitions, $key)
    {
        if (!$customFieldDefinitions[$key]) {
            unset($mergedFieldDefinition[$key]);
        } elseif (isset($mergedFieldDefinition[$key])) {
            $def = $customFieldDefinitions[$key];
            if ($def->getNotEditable()) {
                $mergedFieldDefinition[$key]->setNotEditable(true);
            }
            if ($def->getInvisible()) {
                if ($mergedFieldDefinition[$key] instanceof ClassDefinition\Data\Objectbricks) {
                    unset($mergedFieldDefinition[$key]);
                    return;
                } else {
                    $mergedFieldDefinition[$key]->setInvisible(true);
                }
            }
            if ($def->title) {
                $mergedFieldDefinition[$key]->setTitle($def->title);
            }
        }
    }