Added API method Item->pop()

src/pocketmine/block/FlowerPot.php

@@ -112,14 +112,8 @@ class FlowerPot extends Flowable{
 
 		$this->setDamage(self::STATE_FULL); //specific damage value is unnecessary, it just needs to be non-zero to show an item.
 		$this->getLevel()->setBlock($this, $this, true, false);
-		$pot->setItem($item);
+		$pot->setItem($item->pop());
 
-		if($player instanceof Player){
-			if($player->isSurvival()){
-				$item->setCount($item->getCount() - 1);
-				$player->getInventory()->setItemInHand($item->getCount() > 0 ? $item : ItemFactory::get(Item::AIR));
-			}
-		}
 		return true;
 	}
 

src/pocketmine/block/ItemFrame.php

@@ -63,16 +63,8 @@ class ItemFrame extends Flowable{
 
 		if($tile->hasItem()){
 			$tile->setItemRotation(($tile->getItemRotation() + 1) % 8);
-		}else{
+		}elseif(!$item->isNull()){
-			if($item->getCount() > 0){
+			$tile->setItem($item->pop());
-				$frameItem = clone $item;
-				$frameItem->setCount(1);
-				$item->setCount($item->getCount() - 1);
-				$tile->setItem($frameItem);
-				if($player instanceof Player and $player->isSurvival()){
-					$player->getInventory()->setItemInHand($item->getCount() <= 0 ? ItemFactory::get(Item::AIR) : $item);
-				}
-			}
 		}
 
 		return true;

src/pocketmine/inventory/ShapelessRecipe.php

@@ -82,12 +82,8 @@ class ShapelessRecipe implements CraftingRecipe{
 			throw new \InvalidArgumentException("Shapeless recipes cannot have more than 9 ingredients");
 		}
 
-		$it = clone $item;
-		$it->setCount(1);
-
 		while($item->getCount() > 0){
-			$this->ingredients[] = clone $it;
+			$this->ingredients[] = $item->pop();
-			$item->setCount($item->getCount() - 1);
 		}
 
 		return $this;
@@ -105,7 +101,7 @@ class ShapelessRecipe implements CraftingRecipe{
 			}
 			if($ingredient->equals($item, !$item->hasAnyDamageValue(), $item->hasCompoundTag())){
 				unset($this->ingredients[$index]);
-				$item->setCount($item->getCount() - 1);
+				$item->pop();
 			}
 		}
 

src/pocketmine/item/Item.php

@@ -643,6 +643,25 @@ class Item implements ItemIds, \JsonSerializable{
 		return $this;
 	}
 
+	/**
+	 * Pops an item from the stack and returns it, decreasing the stack count of this item stack by one.
+	 * @return Item
+	 *
+	 * @throws \InvalidStateException if the count is less than or equal to zero, or if the stack is air.
+	 */
+	public function pop() : Item{
+		if($this->isNull()){
+			throw new \InvalidStateException("Cannot pop an item from a null stack");
+		}
+
+		$item = clone $this;
+		$item->setCount(1);
+
+		$this->count--;
+
+		return $item;
+	}
+
 	public function isNull() : bool{
 		return $this->count <= 0 or $this->id === Item::AIR;
 	}

src/pocketmine/level/Level.php

@@ -1823,10 +1823,7 @@ class Level implements ChunkManager, Metadatable{
 			$this->broadcastLevelSoundEvent($hand, LevelSoundEventPacket::SOUND_PLACE, 1, $hand->getId());
 		}
 
-		$item->setCount($item->getCount() - 1);
+		$item->pop();
-		if($item->getCount() <= 0){
-			$item = ItemFactory::get(Item::AIR, 0, 0);
-		}
 
 		return true;
 	}

src/pocketmine/tile/Furnace.php

@@ -201,10 +201,7 @@ class Furnace extends Spawnable implements InventoryHolder, Container, Nameable{
 		}
 
 		if($this->namedtag->BurnTime->getValue() > 0 and $ev->isBurning()){
-			$fuel->setCount($fuel->getCount() - 1);
+			$fuel->pop();
-			if($fuel->getCount() === 0){
-				$fuel = ItemFactory::get(Item::AIR, 0, 0);
-			}
 			$this->inventory->setFuel($fuel);
 		}
 	}
@@ -241,10 +238,7 @@ class Furnace extends Spawnable implements InventoryHolder, Container, Nameable{
 
 					if(!$ev->isCancelled()){
 						$this->inventory->setResult($ev->getResult());
-						$raw->setCount($raw->getCount() - 1);
+						$raw->pop();
-						if($raw->getCount() === 0){
-							$raw = ItemFactory::get(Item::AIR, 0, 0);
-						}
 						$this->inventory->setSmelting($raw);
 					}