@Nullable
  static DirectoryPathMatcher root(@NotNull GotoFileModel model, @NotNull String pattern) {
    DirectoryPathMatcher matcher = new DirectoryPathMatcher(model, null, "");
    for (int i = 0; i < pattern.length(); i++) {
      matcher = matcher.appendChar(pattern.charAt(i));
      if (matcher == null) return null;
    }
    return matcher;
  }
@Nullable
  static DirectoryPathMatcher root(@NotNull GotoFileModel model, @NotNull String pattern)