Added VanillaItems::AIR()

we don't usually add VanillaItems entries for blocks since they already exist in VanillaBlocks, but air has a special use case specifically as an itemstack, so we make an exception for this case.

src/item/Food.php

@@ -32,7 +32,7 @@ abstract class Food extends Item implements FoodSourceItem{
 	}
 
 	public function getResidue() : Item{
-		return ItemFactory::air();
+		return VanillaItems::AIR();
 	}
 
 	public function getAdditionalEffects() : array{

src/item/Item.php

@@ -691,7 +691,7 @@ class Item implements \JsonSerializable{
 				$item = LegacyStringToItemParser::getInstance()->parse($idTag->getValue() . ":$meta");
 			}catch(LegacyStringToItemParserException $e){
 				//TODO: improve error handling
-				return ItemFactory::air();
+				return VanillaItems::AIR();
 			}
 			$item->setCount($count);
 		}else{

src/item/ItemFactory.php

@@ -478,6 +478,10 @@ class ItemFactory{
 		return $item;
 	}
 
+	/**
+	 * @deprecated
+	 * @see VanillaItems::AIR()
+	 */
 	public static function air() : Item{
 		return self::getInstance()->get(ItemIds::AIR, 0, 0);
 	}

src/item/VanillaItems.php

@@ -32,6 +32,7 @@ use pocketmine\utils\CloningRegistryTrait;
  * @generate-registry-docblock
  *
  * @method static Boat ACACIA_BOAT()
+ * @method static ItemBlock AIR()
  * @method static Apple APPLE()
  * @method static Arrow ARROW()
  * @method static Potion AWKWARD_POTION()
@@ -392,6 +393,8 @@ final class VanillaItems{
 
 	protected static function setup() : void{
 		$factory = ItemFactory::getInstance();
+		self::register("air", $factory->get(ItemIds::AIR, 0, 0));
+
 		self::register("acacia_boat", $factory->get(333, 4));
 		self::register("apple", $factory->get(260));
 		self::register("arrow", $factory->get(262));