Prevent admin users from adding out of stock products into manual orders in wp-admin in WooCommerce on child sites.
Snippet Type
Execute on Child Sites
Snippet
add_filter( 'woocommerce_ajax_add_order_item_validation', 'wc_woocommerce_ajax_add_order_item_validation', 10, 2 );
function wc_woocommerce_ajax_add_order_item_validation( $validation_error, $product ) {
if ( $validation_error && !$product->is_in_stock() ) {
$validation_error->add( 'product-out-of-stock', __('Product Out of Stock', 'woocommerce') );
}
return $validation_error;
}