From aa03ced86ca4a8e4058b6cad5e5f3f2fa22845f3 Mon Sep 17 00:00:00 2001
From: Andrew Nicols <andrew@nicols.co.uk>
Date: Thu, 26 May 2016 13:57:31 +0800
Subject: [PATCH 1/2] MDL-54734 user: Add tests to demonstrate multi-user
 issues

---
 lib/tests/user_test.php | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/lib/tests/user_test.php b/lib/tests/user_test.php
index 03192a5c652..7aea5a4ec53 100644
--- a/lib/tests/user_test.php
+++ b/lib/tests/user_test.php
@@ -404,4 +404,28 @@ class core_user_testcase extends advanced_testcase {
         $this->setExpectedException('coding_exception', 'Invalid property requested, or the property does not has a default value.');
         core_user::get_property_default('firstname');
     }
+
+    /**
+     * Ensure that the noreply user is not cached.
+     */
+    public function test_get_noreply_user() {
+        global $CFG;
+
+        // Create a new fake language 'xx' with the 'noreplyname'.
+        $langfolder = $CFG->dataroot . '/lang/xx';
+        check_dir_exists($langfolder);
+        $langconfig = "<?php\n\defined('MOODLE_INTERNAL') || die();";
+        file_put_contents($langfolder . '/langconfig.php', $langconfig);
+        $langconfig = "<?php\n\$string['noreplyname'] = 'XXX';";
+        file_put_contents($langfolder . '/moodle.php', $langconfig);
+
+        $CFG->lang='en';
+        $enuser = \core_user::get_noreply_user();
+
+        $CFG->lang='xx';
+        $xxuser = \core_user::get_noreply_user();
+
+        $this->assertNotEquals($enuser, $xxuser);
+    }
+
 }

From ec907228701299fa50634cc88d5206e061b18971 Mon Sep 17 00:00:00 2001
From: Simey Lameze <simey@moodle.com>
Date: Wed, 8 Jun 2016 10:18:45 +0800
Subject: [PATCH 2/2] MDL-54734 core_user: do not cache dummy user records

---
 lib/classes/user.php | 36 +++++++++++++++++++-----------------
 1 file changed, 19 insertions(+), 17 deletions(-)

diff --git a/lib/classes/user.php b/lib/classes/user.php
index 5a94658ed47..6a10819a94f 100644
--- a/lib/classes/user.php
+++ b/lib/classes/user.php
@@ -152,14 +152,15 @@ class core_user {
         // If noreply user is set then use it, else create one.
         if (!empty($CFG->noreplyuserid)) {
             self::$noreplyuser = self::get_user($CFG->noreplyuserid);
+            self::$noreplyuser->emailstop = 1; // Force msg stop for this user.
+            return self::$noreplyuser;
+        } else {
+            // Do not cache the dummy user record to avoid language internationalization issues.
+            $noreplyuser = self::get_dummy_user_record();
+            $noreplyuser->maildisplay = '1'; // Show to all.
+            $noreplyuser->emailstop = 1;
+            return $noreplyuser;
         }
-
-        if (empty(self::$noreplyuser)) {
-            self::$noreplyuser = self::get_dummy_user_record();
-            self::$noreplyuser->maildisplay = '1'; // Show to all.
-        }
-        self::$noreplyuser->emailstop = 1; // Force msg stop for this user.
-        return self::$noreplyuser;
     }
 
     /**
@@ -182,18 +183,19 @@ class core_user {
         // If custom support user is set then use it, else if supportemail is set then use it, else use noreply.
         if (!empty($CFG->supportuserid)) {
             self::$supportuser = self::get_user($CFG->supportuserid, '*', MUST_EXIST);
-        }
-
-        // Try sending it to support email if support user is not set.
-        if (empty(self::$supportuser) && !empty($CFG->supportemail)) {
-            self::$supportuser = self::get_dummy_user_record();
-            self::$supportuser->id = self::SUPPORT_USER;
-            self::$supportuser->email = $CFG->supportemail;
+        } else if (empty(self::$supportuser) && !empty($CFG->supportemail)) {
+            // Try sending it to support email if support user is not set.
+            $supportuser = self::get_dummy_user_record();
+            $supportuser->id = self::SUPPORT_USER;
+            $supportuser->email = $CFG->supportemail;
             if ($CFG->supportname) {
-                self::$supportuser->firstname = $CFG->supportname;
+                $supportuser->firstname = $CFG->supportname;
             }
-            self::$supportuser->username = 'support';
-            self::$supportuser->maildisplay = '1'; // Show to all.
+            $supportuser->username = 'support';
+            $supportuser->maildisplay = '1'; // Show to all.
+            // Unset emailstop to make sure support message is sent.
+            $supportuser->emailstop = 0;
+            return $supportuser;
         }
 
         // Send support msg to admin user if nothing is set above.