private static void assertUrlBasedPointers(@NotNull FilePartNode node) {
    if (node.isUrlBased()) {
      for (FilePartNode child : node.children) {
        assertUrlBasedPointers(child);
      }
    }
    else {
      throw new IllegalStateException("Node for " + node.myFileOrUrl + " is not a url-based");
    }
  }
private static void assertUrlBasedPointers(@NotNull FilePartNode node)