anchor.diff:    });
   }
   
  -void main(Storage storage) {
  -  setUp(() {
  -    return storage.clear();
  -  });
  -
  +void _testCore(Storage storage) {
     test('store pnp', () {
         return storage.addAll(PNP)
           .then((_) {
  
positive.code:   group('Storage', () {
      stores.forEach((String storeName, Storage store) {
        group(storeName, () {
          main(store);
          testNested(store);
          testAM.main(store);
        });
      });
  
negative.code: 
  }
  
  void _testNested(Storage storage) {
    group('nested', () {
      _testCore(new NestedStorage(storage, 'test1'));
  
      test('independant', () {
        var n1 = new NestedStorage(storage, 't1');
  