Upgrade: Support more seamless upgrade to 4.5 by only requiring /cach…

…e/classes/loaders.php if it is present, resolves #708. (#764)

CHANGES.md

@@ -6,6 +6,7 @@ Changes
 
 ### Unreleased
 
+* 2024-11-19 - Upgrade: Support more seamless upgrade to 4.5 by only requiring /cache/classes/loaders.php if it is present, resolves #708.
 * 2024-11-19 - Bugfix: The starred courses popover showed a JavaScript error in the browser JS console, resolves #759.
 * 2024-11-19 - Bugfix: The starred courses popover in the navbar must only be shown if Boost Union or Boost Union child is active, resolves #759.
 * 2024-11-18 - Improvement: Add the possibility to restrict smart menus and smart menu items to site admins and non-site admins only, resolves #421.

classes/cache/loader.php

@@ -26,7 +26,11 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-require_once($CFG->dirroot.'/cache/classes/loaders.php');
+// Require the cache loaders class, but only if the file exists (which is the case before Moodle 4.5).
+// This is just done to support a seamless upgrade to 4.5.
+if (file_exists($CFG->dirroot.'/cache/classes/loaders.php')) {
+    require_once($CFG->dirroot.'/cache/classes/loaders.php');
+}
 
 /**
  * Custom cache loader to handle the smart menus and items deletion.