diff --git a/lib/Twig/Util/DeprecationCollector.php b/lib/Twig/Util/DeprecationCollector.php
index 1e517f5c0..f8e1adba5 100644
--- a/lib/Twig/Util/DeprecationCollector.php
+++ b/lib/Twig/Util/DeprecationCollector.php
@@ -58,7 +58,7 @@ class Twig_Util_DeprecationCollector
 
         foreach ($iterator as $name => $contents) {
             try {
-                $this->twig->parse($this->twig->tokenize($contents, $name));
+                $this->twig->parse($this->twig->tokenize(new Twig_Source($contents, $name)));
             } catch (Twig_Error_Syntax $e) {
                 // ignore templates containing syntax errors
             }