Support for PHP 8.0 and 8.1

upload/catalog/controller/startup/startup.php

@@ -1,5 +1,17 @@
 <?php
 class ControllerStartupStartup extends Controller {
+
+	public function __isset($key) {
+		// To make sure that calls to isset also support dynamic properties from the registry
+		// See https://www.php.net/manual/en/language.oop5.overloading.php#object.isset
+		if ($this->registry) {
+			if ($this->registry->get($key)!==null) {
+				return true;
+			}
+		}
+		return false;
+	}
+
 	public function index() {
 		// Store
 		if ($this->request->server['HTTPS']) {

upload/catalog/model/catalog/product.php

@@ -42,7 +42,7 @@ public function getProduct($product_id) {
 				'height'           => $query->row['height'],
 				'length_class_id'  => $query->row['length_class_id'],
 				'subtract'         => $query->row['subtract'],
-				'rating'           => round($query->row['rating']),
+				'rating'           => round(($query->row['rating']===null) ? 0 : $query->row['rating']),
 				'reviews'          => $query->row['reviews'] ? $query->row['reviews'] : 0,
 				'minimum'          => $query->row['minimum'],
 				'sort_order'       => $query->row['sort_order'],

upload/system/library/db/mysqli.php

@@ -50,7 +50,7 @@ public function query($sql) {
 	}
 
 	public function escape($value) {
-		return $this->connection->real_escape_string($value);
+		return $this->connection->real_escape_string(($value===null) ? '' : $value);
 	}
 
 	public function countAffected() {

upload/system/library/session/db.php

@@ -18,7 +18,7 @@ public function read($session_id) {
 		if ($query->num_rows) {
 			return json_decode($query->row['data'], true);
 		} else {
-			return false;
+			return array();
 		}
 	}