Program: 173491
Project: 173491
Buggy source:
@Override public void start(){
  prussian=companyManager.getPublicCompany(PR_ID);
  phase=getCurrentPhase();
  startPr=!prussian.hasStarted();
  forcedMerge=phase.getName().equals("String_Node_Str");
  forcedStart=phase.getName().equals("String_Node_Str") || forcedMerge;
  mergePr=!prussianIsComplete(gameManager);
  ReportBuffer.add(LocalText.getText("String_Node_Str",PR_ID));
  log.debug("String_Node_Str" + startPr + "String_Node_Str"+ forcedStart+ "String_Node_Str"+ mergePr+ "String_Node_Str"+ forcedMerge);
  step=startPr ? Step.START : Step.MERGE;
  if (step == Step.START) {
    m2=companyManager.getPublicCompany(M2_ID);
    setCurrentPlayer(m2.getPresident());
    ((GameManager_1835)gameManager).setPrussianFormationStartingPlayer(currentPlayer);
    if (forcedStart) {
      executeStartPrussian(true);
      step=Step.MERGE;
    }
  }
  if (step == Step.MERGE) {
    startingPlayer=((GameManager_1835)gameManager).getPrussianFormationStartingPlayer();
    log.debug("String_Node_Str" + startingPlayer.getId());
    setCurrentPlayer(startingPlayer);
    if (forcedMerge) {
      Set<SpecialProperty> sps;
      setFoldablePrePrussians();
      List<Company> foldables=new ArrayList<Company>();
      for (      PrivateCompany company : gameManager.getAllPrivateCompanies()) {
        if (company.isClosed())         continue;
        sps=company.getSpecialProperties();
        if (sps != null && !sps.isEmpty() && Iterables.get(sps,0) instanceof ExchangeForShare) {
          foldables.add(company);
        }
      }
      for (      PublicCompany company : gameManager.getAllPublicCompanies()) {
        if (company.isClosed())         continue;
        sps=company.getSpecialProperties();
        if (sps != null && !sps.isEmpty() && Iterables.get(sps,0) instanceof ExchangeForShare) {
          foldables.add(company);
        }
      }
      executeExchange(foldables,false,true);
      finishRound();
    }
 else {
      findNextMergingPlayer(false);
    }
  }
}

Fixed version (ground truth):
@Override public void start(){
  prussian=companyManager.getPublicCompany(PR_ID);
  phase=getCurrentPhase();
  startPr=!prussian.hasStarted();
  forcedMerge=phase.getName().equals("String_Node_Str");
  forcedStart=phase.getName().equals("String_Node_Str") || forcedMerge;
  mergePr=!prussianIsComplete(gameManager);
  ReportBuffer.add(LocalText.getText("String_Node_Str",PR_ID));
  log.debug("String_Node_Str" + startPr + "String_Node_Str"+ forcedStart+ "String_Node_Str"+ mergePr+ "String_Node_Str"+ forcedMerge);
  step=startPr ? Step.START : Step.MERGE;
  if (step == Step.START) {
    m2=companyManager.getPublicCompany(M2_ID);
    setCurrentPlayer(m2.getPresident());
    ((GameManager_1835)gameManager).setPrussianFormationStartingPlayer(currentPlayer);
    if (forcedStart) {
      executeStartPrussian(true);
      step=Step.MERGE;
    }
  }
  if (step == Step.MERGE) {
    startingPlayer=((GameManager_1835)gameManager).getPrussianFormationStartingPlayer();
    log.debug("String_Node_Str" + startingPlayer.getId());
    setCurrentPlayer(startingPlayer);
    if (forcedMerge) {
      Set<SpecialProperty> sps;
      setFoldablePrePrussians();
      List<Company> foldables=new ArrayList<Company>();
      for (      PrivateCompany company : gameManager.getAllPrivateCompanies()) {
        if (company.isClosed())         continue;
        sps=company.getSpecialProperties();
        if (sps != null && !sps.isEmpty() && Iterables.get(sps,0) instanceof ExchangeForShare) {
          foldables.add(company);
        }
      }
      for (      PublicCompany company : gameManager.getAllPublicCompanies()) {
        if (company.isClosed())         continue;
        sps=company.getSpecialProperties();
        if (sps != null && !sps.isEmpty() && Iterables.get(sps,0) instanceof ExchangeForShare) {
          foldables.add(company);
        }
      }
      executeExchange(foldables,false,true);
      if (prussian.getNumberOfTrains() > prussian.getCurrentTrainLimit()) {
        step=Step.DISCARD_TRAINS;
      }
 else {
        finishRound();
      }
    }
 else {
      findNextMergingPlayer(false);
    }
  }
}