public function beforeMarshal(Event $event, ArrayObject $data, ArrayObject $options) {
		$field = $this->getConfig('field');
		$property = $this->getConfig('tagsAssoc.propertyName');
		$options['accessibleFields'][$property] = true;

		if (isset($data[$field])) {
			$data[$property] = $this->normalizeTags($data[$field]);
		} elseif ($field !== $property) {
			if (isset($data[$property]) && !is_array($data[$property])) {
				throw new RuntimeException('Your `' . $property . '` property is malformed (expected array instead of string). You configured to save list of tags in `' . $field . '` field.');
			}
		}

		if (isset($data[$field]) && empty($data[$field])) {
			unset($data[$field]);
		}
	}