From 5b244e2bb03d4e942c05722f1034547ad6500970 Mon Sep 17 00:00:00 2001
From: Hugh Davenport <hugh@catalyst.net.nz>
Date: Mon, 9 Apr 2012 19:03:45 +0200
Subject: [PATCH] MDL-32308 Fix error when testing id of guest user

---
 lib/enrollib.php | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/enrollib.php b/lib/enrollib.php
index befe5d2a728..e02a4f7be6f 100644
--- a/lib/enrollib.php
+++ b/lib/enrollib.php
@@ -264,8 +264,8 @@ function enrol_sharing_course($user1, $user2) {
 function enrol_get_shared_courses($user1, $user2, $preloadcontexts = false, $checkexistsonly = false) {
     global $DB, $CFG;
 
-    $user1 = !empty($user1->id) ? $user1->id : $user1;
-    $user2 = !empty($user2->id) ? $user2->id : $user2;
+    $user1 = isset($user1->id) ? $user1->id : $user1;
+    $user2 = isset($user2->id) ? $user2->id : $user2;
 
     if (empty($user1) or empty($user2)) {
         return false;