@NotNull
  private String joinRootsForPresentation(@NotNull Collection<? extends VcsRootError> errors) {
    List<? extends VcsRootError> sortedRoots = sorted(errors, (root1, root2) -> {
      if (root1.getMapping().isDefaultMapping()) return -1;
      if (root2.getMapping().isDefaultMapping()) return 1;
      return root1.getMapping().getDirectory().compareTo(root2.getMapping().getDirectory());
    });
    return StringUtil.join(sortedRoots, ROOT_TO_PRESENTABLE, BR);
  }
@NotNull
  private String joinRootsForPresentation(@NotNull Collection<? extends VcsRootError> errors)