test('getApplicationSupportDirectory', () async {
    final Directory result = await getApplicationSupportDirectory();
    final String uuid = Uuid().v1();
    final File file = File('${result.path}/$uuid.txt');
    file.writeAsStringSync('Hello world!');
    expect(file.readAsStringSync(), 'Hello world!');
    expect(result.listSync(), isNotEmpty);
    file.deleteSync();
  });