protected function tearDown()
 {
     parent::tearDown();
     $storageDir = Yii::getAlias($this->storagePathAlias);
     if (is_dir($storageDir)) {
         FileHelper::removeDirectory($storageDir);
     }
 }
 protected function setUp()
 {
     parent::setUp();
     $app = $this->mockWebApplication();
 }