From 555d01f3278eaaa46463855d340bf19947b5b7b4 Mon Sep 17 00:00:00 2001
From: "Andrey F. Mindubaev" <covex.mobile@gmail.com>
Date: Mon, 26 Mar 2018 09:53:48 +0300
Subject: [PATCH] Small optimization for Twig_NodeTraverser::traverseForVisitor

---
 lib/Twig/NodeTraverser.php | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/Twig/NodeTraverser.php b/lib/Twig/NodeTraverser.php
index 787629ce3..f00a0bf5c 100644
--- a/lib/Twig/NodeTraverser.php
+++ b/lib/Twig/NodeTraverser.php
@@ -70,8 +70,10 @@ class Twig_NodeTraverser
         $node = $visitor->enterNode($node, $this->env);
 
         foreach ($node as $k => $n) {
-            if (false !== $n = $this->traverseForVisitor($visitor, $n)) {
-                $node->setNode($k, $n);
+            if (false !== $m = $this->traverseForVisitor($visitor, $n)) {
+                if ($m !== $n) {
+                    $node->setNode($k, $m);
+                }
             } else {
                 $node->removeNode($k);
             }