code: private void onFinish() {
          if (planRequired && state.getTestSet().getPlan() == null) {
              throw new ParserException("Missing TAP Plan.");
          }
          parseDiagnostics();
  
          while (!states.isEmpty() && state.getIndentationLevel() > baseIndentation) {
              state = states.pop();
          }
      }
docs: Called after the rest of the stream has been processed.