MDL-70920 core: prevent calls to call_user_fun_array() with assoc array

lib/moodlelib.php

@@ -8062,6 +8062,16 @@ function component_callback($component, $function, array $params = array(), $def
 
     $functionname = component_callback_exists($component, $function);
 
+    if ($params && (array_keys($params) !== range(0, count($params) - 1))) {
+        // PHP 8 allows to have associative arrays in the call_user_func_array() parameters but
+        // PHP 7 does not. Using associative arrays can result in different behavior in different PHP versions.
+        // See https://php.watch/versions/8.0/named-parameters#named-params-call_user_func_array
+        // This check can be removed when minimum PHP version for Moodle is raised to 8.
+        debugging('Parameters array can not be an associative array while Moodle supports both PHP 7 and PHP 8.',
+            DEBUG_DEVELOPER);
+        $params = array_values($params);
+    }
+
     if ($functionname) {
         // Function exists, so just return function result.
         $ret = call_user_func_array($functionname, $params);