From cd716fb61b58ac9e059310c223491e366a47ee23 Mon Sep 17 00:00:00 2001
From: Robbie Averill <robbie@silverstripe.com>
Date: Thu, 10 May 2018 10:32:00 +1200
Subject: [PATCH] Switch check for is_string

---
 src/ORM/Hierarchy/MarkedSet.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/ORM/Hierarchy/MarkedSet.php b/src/ORM/Hierarchy/MarkedSet.php
index 52b287a63..a2adda78d 100644
--- a/src/ORM/Hierarchy/MarkedSet.php
+++ b/src/ORM/Hierarchy/MarkedSet.php
@@ -333,7 +333,7 @@ class MarkedSet
         $parentNode->setField('markingClasses', $this->markingClasses($data['node']));
 
         // Evaluate custom context
-        if (!is_array($context) && is_callable($context)) {
+        if (!is_string($context) && is_callable($context)) {
             $context = call_user_func($context, $data['node']);
         }
         if ($context) {