WooCommerce Subscriptions check if the current user has an active subscription

functions.php

<?php

function yanco_has_active_subscription( $user_id = '' ) {
    if( function_exists( 'wcs_user_has_subscription' ) ) {
		// When a $user_id is not specified, get the current user Id
		if( '' == $user_id && is_user_logged_in() ) {
			$user_id = get_current_user_id();
		}

		// User not logged in we return false
		if( $user_id == 0 ) {
			return false;
		}   

		return wcs_user_has_subscription( $user_id, '', 'active' );
	}

	return false;
}