Fix race condition in Environment::loadTemplate

lib/Twig/Cache/Filesystem.php

@@ -41,20 +41,12 @@ class Twig_Cache_Filesystem implements Twig_CacheInterface
         return $this->directory.'/'.$hash[0].'/'.$hash[1].'/'.$hash.'.php';
     }
 
-    /**
-     * {@inheritdoc}
-     */
-    public function has($key)
-    {
-        return is_file($key);
-    }
-
     /**
      * {@inheritdoc}
      */
     public function load($key)
     {
-        require_once $key;
+        @include_once $key;
     }
 
     /**
@@ -98,6 +90,6 @@ class Twig_Cache_Filesystem implements Twig_CacheInterface
      */
     public function getTimestamp($key)
     {
-        return filemtime($key);
+        return (int) @filemtime($key);
     }
 }

lib/Twig/Cache/Null.php

@@ -16,22 +16,12 @@
  */
 class Twig_Cache_Null implements Twig_CacheInterface
 {
-    private $buffer = array();
-
     /**
      * {@inheritdoc}
      */
     public function generateKey($name, $className)
     {
-        return $className;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function has($key)
-    {
-        return false;
+        return '';
     }
 
     /**
@@ -39,7 +29,6 @@ class Twig_Cache_Null implements Twig_CacheInterface
      */
     public function write($key, $content)
     {
-        $this->buffer[$key] = $content;
     }
 
     /**
@@ -47,9 +36,6 @@ class Twig_Cache_Null implements Twig_CacheInterface
      */
     public function load($key)
     {
-        eval('?>'.$this->buffer[$key]);
-
-        unset($this->buffer[$key]);
     }
 
     /**
@@ -57,7 +43,6 @@ class Twig_Cache_Null implements Twig_CacheInterface
      */
     public function getTimestamp($key)
     {
-        // never called as has() always returns false
         return 0;
     }
 }

lib/Twig/CacheInterface.php

@@ -30,15 +30,6 @@ interface Twig_CacheInterface
      */
     public function generateKey($name, $className);
 
-    /**
-     * Checks if the cache key exists.
-     *
-     * @param string $key The cache key
-     *
-     * @return bool true if the cache key exists, false otherwise
-     */
-    public function has($key);
-
     /**
      * Writes the compiled template to cache.
      *

lib/Twig/Environment.php

@@ -375,15 +375,19 @@ class Twig_Environment
                 $key = $this->cache->generateKey($name, $cls);
             }
 
-            if (!$this->cache->has($key) || ($this->isAutoReload() && !$this->isTemplateFresh($name, $this->cache->getTimestamp($key)))) {
+            if (!$this->isAutoReload() || $this->isTemplateFresh($name, $this->cache->getTimestamp($key))) {
+                $this->cache->load($key);
+            }
+
+            if (!class_exists($cls, false)) {
+                $content = $this->compileSource($this->getLoader()->getSource($name), $name);
                 if ($this->bcWriteCacheFile) {
                     $this->writeCacheFile($key, $this->compileSource($this->getLoader()->getSource($name), $name));
                 } else {
                     $this->cache->write($key, $this->compileSource($this->getLoader()->getSource($name), $name));
                 }
+                eval('?>'.$content);
             }
-
-            $this->cache->load($key);
         }
 
         if (!$this->runtimeInitialized) {