Make file cache tolerant for trailing (back)slashes on directory configuration.

lib/Twig/Cache/Filesystem.php

@@ -27,7 +27,7 @@ class Twig_Cache_Filesystem implements Twig_CacheInterface
      */
     public function __construct($directory, $options = 0)
     {
-        $this->directory = $directory;
+        $this->directory = rtrim($directory, '\/').'/';
         $this->options = $options;
     }
 
@@ -38,7 +38,7 @@ class Twig_Cache_Filesystem implements Twig_CacheInterface
     {
         $hash = hash('sha256', $className);
 
-        return $this->directory.'/'.$hash[0].$hash[1].'/'.$hash.'.php';
+        return $this->directory.$hash[0].$hash[1].'/'.$hash.'.php';
     }
 
     /**

test/Twig/Tests/Cache/FilesystemTest.php

@@ -159,6 +159,31 @@ class Twig_Tests_Cache_FilesystemTest extends PHPUnit_Framework_TestCase
         $this->assertSame(0, $this->cache->getTimestamp($key));
     }
 
+    /**
+     * Test file cache is tolerant towards trailing (back)slashes on the configured cache directory.
+     *
+     * @dataProvider provideDirectories
+     */
+    public function testGenerateKey($expected, $input)
+    {
+        $cache = new Twig_Cache_Filesystem($input);
+        $this->assertRegExp($expected, $cache->generateKey('_test_', get_class($this)));
+    }
+
+    public function provideDirectories()
+    {
+        $pattern = '#a/b/[a-zA-Z0-9]+/[a-zA-Z0-9]+.php$#';
+
+        return array(
+            array($pattern, 'a/b'),
+            array($pattern, 'a/b/'),
+            array($pattern, 'a/b\\'),
+            array($pattern, 'a/b\\/'),
+            array($pattern, 'a/b\\//'),
+            array('#/'.substr($pattern, 1), '/a/b'),
+        );
+    }
+
     private function generateSource()
     {
         return strtr('<?php class {{classname}} {}', array(