Fix directory reading. Return FALSE on directory end instead empty string for avoiding infinity readdir cycles.

src/Stream/DirectoryHandle.php

@@ -84,6 +84,8 @@ class DirectoryHandle extends AbstractHandle
                 return $name;
             }
         }
+
+        return false;
     }
 
     public function write($content)

test/acceptance/Stream/StreamWrapper/ReadDirAcceptanceTest.php

@@ -0,0 +1,23 @@
+<?php
+namespace Vfs\Stream\StreamWrapper;
+
+use Vfs\Test\AcceptanceTestCase;
+
+class ReadDirAcceptanceTest extends AcceptanceTestCase
+{
+    protected $tree = [
+        'foo' => [
+            'bar' => 'baz'
+        ]
+    ];
+
+    public function testReadDirectory()
+    {
+        $dHandler = opendir("$this->scheme:///foo");
+        $expects = ['bar' => true, '.' => true, '..' => true];
+        while(($file = readdir($dHandler)) !== false) {
+            $this->assertArrayHasKey($file, $expects);
+        }
+    }
+}
+