turn string The partner code.
	 */
	public function get_partner_code( $type ) {
		switch ( $type ) {
			case self::AFFILIATE_CODE:
				/**
				 * Allow to filter the affiliate code.
				 *
				 * @since partner-1.0.0
				 * @since-jetpack 6.9.0
				 * @since 2.0.0
				 *
				 * @param string $affiliate_code The affiliate code, blank by default.
				 */
				return apply_filters( 'jetpack_affiliate_code', get_option( 'jetpack_affiliate_code', '' ) );
			case self::SUBSIDIARY_CODE:
				/**
				 * Allow to filter the partner subsidiary id.
				 *
				 * @since partner-1.0.0
				 * @since 2.0.0
				 *
				 * @param string $subsidiary_id The partner subsidiary id, blank by default.
				 */
				return apply_filters(
					'jetpack_partner_subsidiary_id',
					get_option( 'jetpack_partner_subsidiary_id', '' )
				);
			default:
				return '';
		}
	}

	/**
	 * Resets the singleton for testing purposes.
	 */
	public static function reset() {
		self::$instance = null;
	}
}