Program: 174553
Project: 174553
Buggy source:
public static ExitHole create(World world,BlockPos pos,double height,boolean meltRocks){
  ArrayList<BlockPos> blocksToDelete=new ArrayList<BlockPos>();
  float shortestLength=Float.MAX_VALUE;
  char direction='o';
  int brightestLight=0;
  for (int x=-9; x <= 9; ++x) {
    BlockPos check=pos.add(x,0,0);
    if (world.isAirBlock(check) && x <= shortestLength && world.getLight(check) >= brightestLight) {
      brightestLight=world.getLight(check);
      shortestLength=Math.abs(x);
      if (x == 0) {
        direction='o';
      }
 else       if (x > 0) {
        direction='e';
      }
 else {
        direction='w';
      }
    }
  }
  for (int y=0; y < height; ++y) {
    blocksToDelete.add(pos.up(y));
  }
  for (int z=-9; z <= 9; ++z) {
    BlockPos check=pos.add(0,0,z);
    if (world.isAirBlock(check) && z <= shortestLength && world.getLight(check) >= brightestLight) {
      brightestLight=world.getLight(check);
      shortestLength=Math.abs(z);
      if (z == 0) {
        direction='o';
      }
 else       if (z > 0) {
        direction='s';
      }
 else {
        direction='n';
      }
    }
  }
switch (direction) {
case 'n':
    for (int z=0; z <= shortestLength; ++z) {
      for (int y=0; y < height; ++y) {
        blocksToDelete.add(pos.add(0,y,-z));
      }
    }
  break;
case 's':
for (int z=0; z <= shortestLength; ++z) {
  for (int y=0; y < height; ++y) {
    blocksToDelete.add(pos.add(0,y,z));
  }
}
break;
case 'e':
for (int x=0; x <= shortestLength; ++x) {
for (int y=0; y < height; ++y) {
blocksToDelete.add(pos.add(x,y,0));
}
}
break;
case 'w':
for (int x=0; x <= shortestLength; ++x) {
for (int y=0; y <= height; ++y) {
blocksToDelete.add(pos.add(-x,y,0));
}
}
break;
}
return new ExitHole(blocksToDelete.toArray(new BlockPos[0]),blocksToDelete.size() <= height,meltRocks,pos.getY());
}

Fixed version (ground truth):
public static ExitHole create(World world,BlockPos pos,double height,boolean meltRocks){
  ArrayList<BlockPos> blocksToDelete=new ArrayList<BlockPos>();
  float shortestLength=Float.MAX_VALUE;
  char direction='o';
  int brightestLight=0;
  for (int x=-9; x <= 9; ++x) {
    BlockPos check=pos.add(x,0,0);
    if (world.isAirBlock(check) && Math.abs(x) <= shortestLength && world.getLight(check) >= brightestLight) {
      brightestLight=world.getLight(check);
      shortestLength=Math.abs(x);
      if (x == 0) {
        direction='o';
      }
 else       if (x > 0) {
        direction='e';
      }
 else {
        direction='w';
      }
    }
  }
  for (int y=0; y < height; ++y) {
    blocksToDelete.add(pos.up(y));
  }
  for (int z=-9; z <= 9; ++z) {
    BlockPos check=pos.add(0,0,z);
    if (world.isAirBlock(check) && Math.abs(z) <= shortestLength && world.getLight(check) >= brightestLight) {
      brightestLight=world.getLight(check);
      shortestLength=Math.abs(z);
      if (z == 0) {
        direction='o';
      }
 else       if (z > 0) {
        direction='s';
      }
 else {
        direction='n';
      }
    }
  }
switch (direction) {
case 'n':
    for (int z=0; z <= shortestLength; ++z) {
      for (int y=0; y < height; ++y) {
        blocksToDelete.add(pos.add(0,y,-z));
      }
    }
  break;
case 's':
for (int z=0; z <= shortestLength; ++z) {
  for (int y=0; y < height; ++y) {
    blocksToDelete.add(pos.add(0,y,z));
  }
}
break;
case 'e':
for (int x=0; x <= shortestLength; ++x) {
for (int y=0; y < height; ++y) {
blocksToDelete.add(pos.add(x,y,0));
}
}
break;
case 'w':
for (int x=0; x <= shortestLength; ++x) {
for (int y=0; y < height; ++y) {
blocksToDelete.add(pos.add(-x,y,0));
}
}
break;
}
return new ExitHole(blocksToDelete.toArray(new BlockPos[0]),blocksToDelete.size() <= height,meltRocks,pos.getY());
}