Review

class NodeTraversal {
  private void throwUnexpectedException(Exception unexpectedException) {
    // If there's an unexpected exception, try to get the
    // line number of the code that caused it.
    String message = unexpectedException.getMessage();

    // TODO(user): It is possible to get more information if curNode or
    // its parent is missing. We still have the scope stack in which it is still
    // very useful to find out at least which function caused the exception.
    if (!sourceName.isEmpty()) {
      message =
          unexpectedException.getMessage() + "\n" +
          formatNodeContext("Node", curNode) +
          (curNode == null ?
              "" :
              formatNodeContext("Parent", curNode.getParent()));
    }
    compiler.throwInternalError(message, unexpectedException);
  }

}