From 972e6ffe4712d67a6b109e6da084fc6ed91872dc Mon Sep 17 00:00:00 2001
From: Andrew Nicols <andrew@nicols.co.uk>
Date: Wed, 24 Feb 2021 09:05:36 +0800
Subject: [PATCH] MDL-70987 core_form: Use correct id for elementid during
 validation

The id of the formid was being passed instead of the elementid.
---
 lib/formslib.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/formslib.php b/lib/formslib.php
index 8701bbd2e8e..3251ad1bdc7 100644
--- a/lib/formslib.php
+++ b/lib/formslib.php
@@ -2579,7 +2579,7 @@ require(["core/event", "jquery"], function(Event, $) {
                 }
             }
             // This handles both randomised (MDL-65217) and non-randomised IDs.
-            $errorid = preg_replace('/^id_/', 'id_error_', $this->_attributes['id']);
+            $errorid = preg_replace('/^id_/', 'id_error_', $elem->_attributes['id']);
             $validateJS .= '
       ret = validate_' . $this->_formName . '_' . $escapedElementName.'(frm.elements[\''.$elementName.'\'], \''.$escapedElementName.'\') && ret;
       if (!ret && !first_focus) {