@NotNull
    @Override
    List<FileNode> getChildren(@NotNull List<? extends FileNode> oldList) {
      List<FileNode> list = new SmartList<>();
      Mapper mapper = new Mapper(oldList);
      if (showModules) {
        visitContentRoots(project, (file, area) -> list.add(mapper.apply(file, area)));
      }
      else {
        TreeCollector<VirtualFile> collector = TreeCollector.VirtualFileRoots.create();
        visitContentRoots(project, (file, area) -> collector.add(file));
        collector.get().forEach(file -> list.add(mapper.apply(file, file)));
      }
      return list;
    }
@NotNull
    @Override
    List<FileNode> getChildren(@NotNull List<? extends FileNode> oldList)