Program: 109378
Project: 109378
Buggy source:
@Override public synchronized void run(){
  if (eatTask.isActive())   return;
  if (ticksWait > 0) {
    ticksWait--;
    return;
  }
  World world=bot.getWorld();
  MainPlayerEntity player=bot.getPlayer();
  System.out.println("String_Node_Str");
  BlockLocation ourLocation=new BlockLocation((int)(Math.round(player.getX() - 0.5)),(int)player.getY(),(int)(Math.round(player.getZ() - 0.5)));
  boolean flip=false;
  for (int y=point1.getY(); y <= point2.getY(); y++) {
    for (int x=Math.min(point1.getX(),point2.getX()); x <= Math.max(point1.getX(),point2.getX()); x++) {
      int z1=Math.min(point1.getZ(),point2.getZ());
      int z2=Math.max(point1.getZ(),point2.getZ());
      if (flip) {
        int temp=z1;
        z1=z2;
        z2=temp;
      }
      for (int z=z1; flip ? z >= z2 : z <= z2; z+=flip ? -1 : 1) {
        if (startCounterLocation != null && startCounterLocation.getX() == x && startCounterLocation.getY() == y && startCounterLocation.getZ() == z)         continue;
        int id=world.getBlockIdAt(x,y,z);
        if (!BlockType.getById(id).isSolid()) {
          BlockLocation location=new BlockLocation(x,y,z);
          if (startCounterLocation != null) {
            System.out.println(ourLocation + "String_Node_Str" + location);
            BlockLocation original=location;
            BlockLocation below=location.offset(0,-1,0);
            while (!BlockType.getById(world.getBlockIdAt(below)).isSolid() && !world.getPathFinder().getHeuristic().isClimbableBlock(below)) {
              location=below;
              below=below.offset(0,-1,0);
              if (original.getY() - location.getY() >= 5)               return;
            }
            if (!location.equals(ourLocation)) {
              System.out.println("String_Node_Str");
              bot.setActivity(new WalkActivity(bot,location));
              ticksWait=4;
              return;
            }
            int index=player.getInventory().getFirstSlot(blockId);
            if (index == -1) {
              System.out.println("String_Node_Str");
              stop();
              return;
            }
            System.out.println("String_Node_Str");
            player.switchHeldItems(index);
            player.placeBlock(startCounterLocation);
            startCounterLocation=null;
          }
          startCounterLocation=location;
        }
      }
      flip=!flip;
    }
  }
}

Fixed version (ground truth):
@Override public synchronized void run(){
  if (eatTask.isActive())   return;
  if (ticksWait > 0) {
    ticksWait--;
    return;
  }
  World world=bot.getWorld();
  MainPlayerEntity player=bot.getPlayer();
  System.out.println("String_Node_Str");
  BlockLocation ourLocation=new BlockLocation(player.getLocation());
  boolean flip=false;
  for (int y=point1.getY(); y <= point2.getY(); y++) {
    for (int x=Math.min(point1.getX(),point2.getX()); x <= Math.max(point1.getX(),point2.getX()); x++) {
      int z1=Math.min(point1.getZ(),point2.getZ());
      int z2=Math.max(point1.getZ(),point2.getZ());
      if (flip) {
        int temp=z1;
        z1=z2;
        z2=temp;
      }
      for (int z=z1; flip ? z >= z2 : z <= z2; z+=flip ? -1 : 1) {
        if (startCounterLocation != null && startCounterLocation.getX() == x && startCounterLocation.getY() == y && startCounterLocation.getZ() == z)         continue;
        int id=world.getBlockIdAt(x,y,z);
        if (!BlockType.getById(id).isSolid()) {
          BlockLocation location=new BlockLocation(x,y,z);
          if (startCounterLocation != null) {
            System.out.println(ourLocation + "String_Node_Str" + location);
            BlockLocation original=location;
            BlockLocation below=location.offset(0,-1,0);
            while (!BlockType.getById(world.getBlockIdAt(below)).isSolid() && !world.getPathFinder().getHeuristic().isClimbableBlock(below)) {
              location=below;
              below=below.offset(0,-1,0);
              if (original.getY() - location.getY() >= 5)               return;
            }
            if (!location.equals(ourLocation)) {
              System.out.println("String_Node_Str");
              bot.setActivity(new WalkActivity(bot,location));
              ticksWait=4;
              return;
            }
            int index=player.getInventory().getFirstSlot(blockId);
            if (index == -1) {
              System.out.println("String_Node_Str");
              stop();
              return;
            }
            System.out.println("String_Node_Str");
            player.switchHeldItems(index);
            player.placeBlock(startCounterLocation);
            startCounterLocation=null;
          }
          startCounterLocation=location;
        }
      }
      flip=!flip;
    }
  }
}