anchor.diff:          nullptr, COINIT_APARTMENTTHREADED | COINIT_DISABLE_OLE1DDE);
       expect(hr, equals(S_OK));
   
  -    final ptrFactory = COMObject.allocate().addressOf;
  -    final ptrSaveDialog = COMObject.allocate().addressOf;
  +    final ptrFactory = zeroAllocate<COMObject>();
  +    final ptrSaveDialog = zeroAllocate<COMObject>();
   
       hr = CoGetClassObject(
           GUID.fromString(CLSID_FileSaveDialog).addressOf,
  
positive.code:   });
  
    test('IIDFromString', () {
      final guid = GUID.allocate();
      final hr = IIDFromString(TEXT(IID_IShellItem2), guid.addressOf);
      expect(hr, equals(S_OK));
  
      expect(guid.toString(), equalsIgnoringCase(IID_IShellItem2));
  
      free(guid.addressOf);
    });
  
    test('Create COM object without calling CoInitialize should fail', () {
  
negative.code:         nullptr, COINIT_APARTMENTTHREADED | COINIT_DISABLE_OLE1DDE);
      expect(hr, equals(S_OK));
  
      final ptr = zeroAllocate<COMObject>();
  
      hr = CoCreateInstance(
          GUID.fromString(CLSID_FileSaveDialog).addressOf,
  