Craft\Neo_SettingsModel::getGroups PHP Method

    public function getGroups()
    {
        if (!isset($this->_groups)) {
            if ($this->_neoField && !empty($this->_neoField->id)) {
                $this->_groups = craft()->neo->getGroupsByFieldId($this->_neoField->id);
            } else {
                $this->_groups = [];
            }
        }
        return $this->_groups;
    }