From 840cb4e4d6422a179e36cdc1b04fccbcd00ecdd8 Mon Sep 17 00:00:00 2001
From: David Monllao <davidm@moodle.com>
Date: Thu, 9 Apr 2015 14:59:17 +0800
Subject: [PATCH] MDL-49803 mod_quiz: Fixing overrides restore

---
 mod/quiz/backup/moodle2/restore_quiz_stepslib.php | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/mod/quiz/backup/moodle2/restore_quiz_stepslib.php b/mod/quiz/backup/moodle2/restore_quiz_stepslib.php
index de7f1ebd667..1b697475cd2 100644
--- a/mod/quiz/backup/moodle2/restore_quiz_stepslib.php
+++ b/mod/quiz/backup/moodle2/restore_quiz_stepslib.php
@@ -304,8 +304,13 @@ class restore_quiz_activity_structure_step extends restore_questions_activity_st
 
         $data->quiz = $this->get_new_parentid('quiz');
 
-        $data->userid = $this->get_mappingid('user', $data->userid);
-        $data->groupid = $this->get_mappingid('group', $data->groupid);
+        if ($data->userid !== null) {
+            $data->userid = $this->get_mappingid('user', $data->userid);
+        }
+
+        if ($data->groupid !== null) {
+            $data->groupid = $this->get_mappingid('group', $data->groupid);
+        }
 
         $data->timeopen = $this->apply_date_offset($data->timeopen);
         $data->timeclose = $this->apply_date_offset($data->timeclose);