From be492e2a8f2eed8e044b2099cbfd043f9f755f66 Mon Sep 17 00:00:00 2001
From: Tim Hunt <T.J.Hunt@open.ac.uk>
Date: Tue, 2 Apr 2019 14:12:45 +0100
Subject: [PATCH] MDL-65245 question engine: response vars should always be PHP
 strings

---
 question/engine/questionattempt.php | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/question/engine/questionattempt.php b/question/engine/questionattempt.php
index 1a9bd04633b..efc5425d045 100644
--- a/question/engine/questionattempt.php
+++ b/question/engine/questionattempt.php
@@ -1069,6 +1069,13 @@ class question_attempt {
                     $var = null;
                 }
 
+                if ($var !== null) {
+                    // Ensure that, if set, $var is a string. This is because later, after
+                    // it has been saved to the database and loaded back it will be a string,
+                    // so better if the type is predictably always a string.
+                    $var = (string) $var;
+                }
+
                 return $var;
         }
     }