WooCommerce Critical error at order status change - php

Question

I am using this code to add admin action to change bulk order statuses.
I have custom build status with name "wc-to-order".
Unfortunatelly, I got error when use code from Woo bulk action.
Can anyone help me to resolve it?
This is code:
add_action( 'admin_action_wc-to-order', 'add_new_order_status_wc_on_hold' ); // admin_action_{action name}
function add_new_order_status_wc_on_hold() {
// if an array with order IDs is not presented, exit the function
if( !isset( $_REQUEST['post'] ) && !is_array( $_REQUEST['post'] ) )
return;
foreach( $_REQUEST['post'] as $order_id ) {
$order = new WC_Order( $order_id );
$order_note = 'That\'s what happened by bulk edit:';
$order->update_status( 'wc-to-order', $order_note, true );
}
$location = add_query_arg( array(
'post_type' => 'shop_order',
'wc-to-order' => 1, // markED_awaiting_shipment=1 is just the $_GET variable for notices
'changed' => count( $_REQUEST['post'] ), // number of changed orders
'ids' => join( $_REQUEST['post'], ',' ),
'post_status' => 'all'
), 'edit.php' );
wp_redirect( admin_url( $location ) );
exit;
}
I got this in debug log
PHP Fatal error: Uncaught TypeError: join(): Argument #2 ($array) must be of type ?array, string given in /public_html/sitename/wp-content/themes/themename/functions.php:648

Answer 1

From the log, it appears that $_REQUEST['post'] may not be an array. In the below code we first check if it is an array. If it is not, then we cast it as array.
add_action( 'admin_action_wc-to-order', 'add_new_order_status_wc_on_hold' ); // admin_action_{action name}
function add_new_order_status_wc_on_hold() {
// if an array with order IDs is not presented, exit the function
if( !isset( $_REQUEST['post'] ) ) {
return;
}
//check if it is an array. If not, cast it as array
$orders_array = is_array($_REQUEST['post']) ? $_REQUEST['post'] : array($_REQUEST['post']);
foreach( $orders_array as $order_id ) {
$order = new WC_Order( $order_id );
$order_note = 'That\'s what happened by bulk edit:';
$order->update_status( 'wc-to-order', $order_note, true );
}
$location = add_query_arg( array(
'post_type' => 'shop_order',
'wc-to-order' => 1, // markED_awaiting_shipment=1 is just the $_GET variable for notices
'changed' => count( $orders_array ), // number of changed orders
'ids' => join( $orders_array, ',' ),
'post_status' => 'all'
), 'edit.php' );
wp_redirect( admin_url( $location ) );
exit;
}
This way we ensure that array is always provided to join function.