Program: 141575
Project: 141575
Buggy source:
@SuppressWarnings("String_Node_Str") @Override public void run(final CommandSender cs,String label,String[] args){
  if (!r.perm(cs,"String_Node_Str",false,true)) {
    return;
  }
  if (!r.isPlayer(cs)) {
    return;
  }
  Player p=(Player)cs;
  if (args.length < 1) {
    r.sendMes(cs,"String_Node_Str");
    return;
  }
  Block b=LocationUtil.getAbsoluteTarget(p).getBlock();
  if ((b == null) || b.getState() == null || (!(b.getState() instanceof Sign))) {
    if (b != null && b.getState() != null) {
      r.sendMes(cs,"String_Node_Str","String_Node_Str",ItemUtil.getName(new ItemStack(b.getType(),b.getData())));
    }
 else {
      r.sendMes(cs,"String_Node_Str");
    }
    return;
  }
  Sign s=(Sign)b.getState();
  int lineNumber;
  try {
    lineNumber=Integer.parseInt(args[0]);
    lineNumber--;
  }
 catch (  NumberFormatException e) {
    r.sendMes(cs,"String_Node_Str");
    return;
  }
  if ((lineNumber < 0) || (lineNumber > 3)) {
    r.sendMes(cs,"String_Node_Str");
    return;
  }
  if (args.length < 2) {
    s.setLine(lineNumber,"String_Node_Str");
    s.update();
    r.sendMes(cs,"String_Node_Str","String_Node_Str",lineNumber + 1);
    return;
  }
  String text=r.getFinalArg(args,1);
  if (r.perm(p,"String_Node_Str",false,false)) {
    s.setLine(0,ChatColor.translateAlternateColorCodes('&',s.getLine(0)));
    s.setLine(1,ChatColor.translateAlternateColorCodes('&',s.getLine(1)));
    s.setLine(2,ChatColor.translateAlternateColorCodes('&',s.getLine(2)));
    s.setLine(3,ChatColor.translateAlternateColorCodes('&',s.getLine(3)));
    text=ChatColor.translateAlternateColorCodes('&',text);
  }
  s.setLine(lineNumber,text);
  s.update();
  r.sendMes(cs,"String_Node_Str","String_Node_Str",lineNumber + 1,"String_Node_Str",r.getFinalArg(args,1));
  return;
}

Fixed version (ground truth):
@SuppressWarnings("String_Node_Str") @Override public void run(final CommandSender cs,String label,String[] args){
  if (!r.perm(cs,"String_Node_Str",false,true)) {
    return;
  }
  if (!r.isPlayer(cs)) {
    return;
  }
  Player p=(Player)cs;
  if (!r.checkArgs(args,0)) {
    r.sendMes(cs,"String_Node_Str");
    return;
  }
  Block b=LocationUtil.getAbsoluteTarget(p).getBlock();
  if ((b == null) || b.getState() == null || (!(b.getState() instanceof Sign))) {
    if (b != null && b.getState() != null) {
      r.sendMes(cs,"String_Node_Str","String_Node_Str",ItemUtil.getName(new ItemStack(b.getType(),b.getData())));
    }
 else {
      r.sendMes(cs,"String_Node_Str");
    }
    return;
  }
  Sign s=(Sign)b.getState();
  int lineNumber;
  try {
    lineNumber=Integer.parseInt(args[0]);
    lineNumber--;
  }
 catch (  NumberFormatException e) {
    r.sendMes(cs,"String_Node_Str");
    return;
  }
  if ((lineNumber < 0) || (lineNumber > 3)) {
    r.sendMes(cs,"String_Node_Str");
    return;
  }
  if (args.length < 2) {
    s.setLine(lineNumber,"String_Node_Str");
    s.update();
    r.sendMes(cs,"String_Node_Str","String_Node_Str",lineNumber + 1);
    return;
  }
  String text=r.getFinalArg(args,1);
  if (r.perm(p,"String_Node_Str",false,false)) {
    s.setLine(0,ChatColor.translateAlternateColorCodes('&',s.getLine(0)));
    s.setLine(1,ChatColor.translateAlternateColorCodes('&',s.getLine(1)));
    s.setLine(2,ChatColor.translateAlternateColorCodes('&',s.getLine(2)));
    s.setLine(3,ChatColor.translateAlternateColorCodes('&',s.getLine(3)));
    text=ChatColor.translateAlternateColorCodes('&',text);
  }
  s.setLine(lineNumber,text);
  s.update();
  r.sendMes(cs,"String_Node_Str","String_Node_Str",lineNumber + 1,"String_Node_Str",r.getFinalArg(args,1));
  return;
}