public function testCleanUp()
{
$base = Libraries::get(true, 'resources') . '/tmp/tests';
$this->skipIf(!is_writable($base), "Path `{$base}` is not writable.");
$this->assertTrue(mkdir("{$base}/cleanup_test"));
$this->assertTrue(touch("{$base}/cleanup_test/file"));
$this->assertTrue(touch("{$base}/cleanup_test/.hideme"));
$this->_cleanUp();
$this->assertFileNotExists("{$base}/cleanup_test");
}