1 files changed, 15 insertions, 17 deletions

diff --git a/inc/lib/Twig/NodeTraverser.php b/inc/lib/Twig/NodeTraverser.php
index 28cba1ad..f00a0bf5 100644
--- a/inc/lib/Twig/NodeTraverser.php
+++ b/inc/lib/Twig/NodeTraverser.php
@@ -3,7 +3,7 @@
 /*
  * This file is part of Twig.
  *
- * (c) 2009 Fabien Potencier
+ * (c) Fabien Potencier
  *
  * For the full copyright and license information, please view the LICENSE
  * file that was distributed with this source code.
@@ -12,35 +12,29 @@
 /**
  * Twig_NodeTraverser is a node traverser.
  *
- * It visits all nodes and their children and call the given visitor for each.
+ * It visits all nodes and their children and calls the given visitor for each.
+ *
+ * @final
  *
  * @author Fabien Potencier <fabien@symfony.com>
  */
 class Twig_NodeTraverser
 {
     protected $env;
-    protected $visitors;
+    protected $visitors = array();
 
     /**
-     * Constructor.
-     *
-     * @param Twig_Environment $env      A Twig_Environment instance
-     * @param array            $visitors An array of Twig_NodeVisitorInterface instances
+     * @param Twig_Environment            $env
+     * @param Twig_NodeVisitorInterface[] $visitors
      */
     public function __construct(Twig_Environment $env, array $visitors = array())
     {
         $this->env = $env;
-        $this->visitors = array();
         foreach ($visitors as $visitor) {
             $this->addVisitor($visitor);
         }
     }
 
-    /**
-     * Adds a visitor.
-     *
-     * @param Twig_NodeVisitorInterface $visitor A Twig_NodeVisitorInterface instance
-     */
     public function addVisitor(Twig_NodeVisitorInterface $visitor)
     {
         if (!isset($this->visitors[$visitor->getPriority()])) {
@@ -53,7 +47,7 @@ class Twig_NodeTraverser
     /**
      * Traverses a node and calls the registered visitors.
      *
-     * @param Twig_NodeInterface $node A Twig_NodeInterface instance
+     * @return Twig_NodeInterface
      */
     public function traverse(Twig_NodeInterface $node)
     {
@@ -70,14 +64,16 @@ class Twig_NodeTraverser
     protected function traverseForVisitor(Twig_NodeVisitorInterface $visitor, Twig_NodeInterface $node = null)
     {
         if (null === $node) {
-            return null;
+            return;
         }
 
         $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);
             }
@@ -86,3 +82,5 @@ class Twig_NodeTraverser
         return $visitor->leaveNode($node, $this->env);
     }
 }
+
+class_alias('Twig_NodeTraverser', 'Twig\NodeTraverser', false);