diff --git a/src/Symfony/Component/Routing/Tests/Generator/Dumper/PhpGeneratorDumperTest.php b/src/Symfony/Component/Routing/Tests/Generator/Dumper/PhpGeneratorDumperTest.php
index e55a6ccf88..783d694d1c 100644
--- a/src/Symfony/Component/Routing/Tests/Generator/Dumper/PhpGeneratorDumperTest.php
+++ b/src/Symfony/Component/Routing/Tests/Generator/Dumper/PhpGeneratorDumperTest.php
@@ -91,10 +91,10 @@ class PhpGeneratorDumperTest extends \PHPUnit_Framework_TestCase
         }
         $this->routeCollection->add('Test2', new Route('/testing2'));
 
-        $data = $this->generatorDumper->dump(array(
+        file_put_contents($this->largeTestTmpFilepath, $this->generatorDumper->dump(array(
             'class' => 'ProjectLargeUrlGenerator',
-        ));
-        file_put_contents($this->largeTestTmpFilepath, $data);
+        )));
+        $this->routeCollection = $this->generatorDumper = null;
         include $this->largeTestTmpFilepath;
 
         $projectUrlGenerator = new \ProjectLargeUrlGenerator(new RequestContext('/app.php'));