public override State OnWatcherAdded(FullPath directory, DirectoryWatcherhEntry watcher)
 {
     return(this);
 }
        private static void MergePathChange(IDictionary <FullPath, PathChangeKind> changes, FullPath path, PathChangeKind kind)
        {
            PathChangeKind currentChangeKind;

            if (!changes.TryGetValue(path, out currentChangeKind))
            {
                currentChangeKind = PathChangeKind.None;
            }
            changes[path] = CombineChangeKinds(currentChangeKind, kind);
        }