Program: 164282
Project: 164282
Buggy source:
public Heap drop(Item item,int cell){
  if ((Dungeon.isChallenged(Challenges.NO_FOOD) && (item instanceof Food || item instanceof BlandfruitBush.Seed)) || (Dungeon.isChallenged(Challenges.NO_ARMOR) && item instanceof Armor) || (Dungeon.isChallenged(Challenges.NO_HEALING) && item instanceof PotionOfHealing)|| (Dungeon.isChallenged(Challenges.NO_HERBALISM) && (item instanceof Plant.Seed || item instanceof Dewdrop || item instanceof SeedPouch))|| (Dungeon.isChallenged(Challenges.NO_SCROLLS) && ((item instanceof Scroll && !(item instanceof ScrollOfUpgrade)) || item instanceof ScrollHolder))|| item == null) {
    Heap heap=new Heap();
    ItemSprite sprite=heap.sprite=new ItemSprite();
    sprite.link(heap);
    return heap;
  }
  if ((map[cell] == Terrain.ALCHEMY) && (!(item instanceof Plant.Seed || item instanceof Blandfruit) || item instanceof BlandfruitBush.Seed || (item instanceof Blandfruit && (((Blandfruit)item).potionAttrib != null || heaps.get(cell) != null))|| Dungeon.hero.buff(AlchemistsToolkit.alchemy.class) != null && Dungeon.hero.buff(AlchemistsToolkit.alchemy.class).isCursed())) {
    int n;
    do {
      n=cell + NEIGHBOURS8[Random.Int(8)];
    }
 while (map[n] != Terrain.EMPTY_SP);
    cell=n;
  }
  Heap heap=heaps.get(cell);
  if (heap == null) {
    heap=new Heap();
    heap.pos=cell;
    if (map[cell] == Terrain.CHASM || (Dungeon.level != null && pit[cell])) {
      Dungeon.dropToChasm(item);
      GameScene.discard(heap);
    }
 else {
      heaps.put(cell,heap);
      GameScene.add(heap);
    }
  }
 else   if (heap.type == Heap.Type.LOCKED_CHEST || heap.type == Heap.Type.CRYSTAL_CHEST) {
    int n;
    do {
      n=cell + Level.NEIGHBOURS8[Random.Int(8)];
    }
 while (!Level.passable[n] && !Level.avoid[n]);
    return drop(item,n);
  }
  heap.drop(item);
  if (Dungeon.level != null) {
    press(cell,null);
  }
  return heap;
}

Fixed version (ground truth):
public Heap drop(Item item,int cell){
  if ((Dungeon.isChallenged(Challenges.NO_FOOD) && (item instanceof Food || item instanceof BlandfruitBush.Seed)) || (Dungeon.isChallenged(Challenges.NO_ARMOR) && item instanceof Armor) || (Dungeon.isChallenged(Challenges.NO_HEALING) && item instanceof PotionOfHealing)|| (Dungeon.isChallenged(Challenges.NO_HERBALISM) && (item instanceof Plant.Seed || item instanceof Dewdrop || item instanceof SeedPouch))|| (Dungeon.isChallenged(Challenges.NO_SCROLLS) && ((item instanceof Scroll && !(item instanceof ScrollOfUpgrade)) || item instanceof ScrollHolder))|| item == null) {
    Heap heap=new Heap();
    ItemSprite sprite=heap.sprite=new ItemSprite();
    sprite.link(heap);
    return heap;
  }
  if ((map[cell] == Terrain.ALCHEMY) && (!(item instanceof Plant.Seed || item instanceof Blandfruit) || item instanceof BlandfruitBush.Seed || (item instanceof Blandfruit && (((Blandfruit)item).potionAttrib != null || heaps.get(cell) != null))|| Dungeon.hero.buff(AlchemistsToolkit.alchemy.class) != null && Dungeon.hero.buff(AlchemistsToolkit.alchemy.class).isCursed())) {
    int n;
    do {
      n=cell + NEIGHBOURS8[Random.Int(8)];
    }
 while (map[n] != Terrain.EMPTY_SP);
    cell=n;
  }
  Heap heap=heaps.get(cell);
  if (heap == null) {
    heap=new Heap();
    heap.seen=fieldOfView[cell];
    heap.pos=cell;
    if (map[cell] == Terrain.CHASM || (Dungeon.level != null && pit[cell])) {
      Dungeon.dropToChasm(item);
      GameScene.discard(heap);
    }
 else {
      heaps.put(cell,heap);
      GameScene.add(heap);
    }
  }
 else   if (heap.type == Heap.Type.LOCKED_CHEST || heap.type == Heap.Type.CRYSTAL_CHEST) {
    int n;
    do {
      n=cell + Level.NEIGHBOURS8[Random.Int(8)];
    }
 while (!Level.passable[n] && !Level.avoid[n]);
    return drop(item,n);
  }
  heap.drop(item);
  if (Dungeon.level != null) {
    press(cell,null);
  }
  return heap;
}