public function mkdirDirCanNotCreateNewDirInNonWritingDirectory()
{
vfsStreamWrapper::register();
vfsStreamWrapper::setRoot(new vfsStreamDirectory('root'));
vfsStreamWrapper::getRoot()->addChild(new vfsStreamDirectory('restrictedFolder', 00));
$this->assertFalse(is_writable(vfsStream::url('root/restrictedFolder/')));
$this->assertFalse(mkdir(vfsStream::url('root/restrictedFolder/newFolder')));
$this->assertFalse(vfsStreamWrapper::getRoot()->hasChild('restrictedFolder/newFolder'));
}