Unify plain and type of for items

src/main/java/ch/njol/skript/aliases/ItemData.java

@@ -19,6 +19,9 @@
 import org.bukkit.inventory.ItemFlag;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.ItemMeta;
+import org.bukkit.inventory.meta.MusicInstrumentMeta;
+import org.bukkit.inventory.meta.PotionMeta;
+import org.bukkit.potion.PotionEffect;
 import org.jetbrains.annotations.Nullable;
 
 import java.io.IOException;
@@ -38,7 +41,7 @@ public class ItemData implements Cloneable, YggdrasilExtendedSerializable {
 		Variables.yggdrasil.registerSingleClass(ItemData.class, "NewItemData");
 		Variables.yggdrasil.registerSingleClass(OldItemData.class, "ItemData");
 	}
-	
+
 	/**
 	 * Represents old ItemData (before aliases rework and MC 1.13).
 	 */
@@ -604,7 +607,9 @@ public void deserialize(Fields fields) throws StreamCorruptedException, NotSeria
 	 * <li>Name: custom names made with anvil do not change item type
 	 * </ul>
 	 * @return A modified copy of this item data.
+	 * @deprecated Use {@link #getBaseCopy()} instead if you want a plain copy.
 	 */
+	@Deprecated(since = "INSERT_VERSION", forRemoval = true)
 	public ItemData aliasCopy() {
 		ItemData data = new ItemData();
 		if (stack != null) {
@@ -624,7 +629,63 @@ public ItemData aliasCopy() {
 		data.itemForm = itemForm;
 		return data;
 	}
-
+
+	/**
+	 * Returns a base version of this item data, i.e. only contains
+	 * the minimum ItemMeta info to represent the item, in the case of potions/goat horns.
+ 	 * @return Plain item type.
+	 */
+	public @Nullable ItemData getBaseCopy() {
+		ItemData data = new ItemData();
+		data.type = type;
+		data.blockValues = blockValues;
+		data.itemForm = itemForm;
+		if (stack != null) {
+			data.stack = new ItemStack(type, 1);
+			if (stack.hasItemMeta()) {
+				ItemMeta meta = stack.getItemMeta();
+				if (meta instanceof PotionMeta potionMeta) {
+					copyPotionInfo(potionMeta, data);
+				} else if (meta instanceof MusicInstrumentMeta musicMeta) {
+					copyMusicInfo(musicMeta, data);
+				}
+			}
+		}
+		return data;
+	}
+
+	// Can remove after 1.21.3 is the minimum supported version
+	private static final boolean HAS_CUSTOM_NAME = Skript.methodExists(PotionMeta.class, "hasCustomPotionName");
+
+	private static void copyPotionInfo(PotionMeta potionMeta, ItemData data) {
+		PotionMeta newMeta = (PotionMeta) itemFactory.getItemMeta(data.type);
+		if (newMeta.equals(potionMeta))
+			return;
+		// copy potion meta info
+		if (potionMeta.hasBasePotionType())
+			newMeta.setBasePotionType(potionMeta.getBasePotionType());
+		if (potionMeta.hasCustomEffects()) {
+			for (PotionEffect effect : potionMeta.getCustomEffects()) {
+				newMeta.addCustomEffect(effect, false);
+			}
+		}
+		if (potionMeta.hasColor())
+			newMeta.setColor(potionMeta.getColor());
+		if (HAS_CUSTOM_NAME && potionMeta.hasCustomPotionName())
+			newMeta.setCustomPotionName(potionMeta.getCustomPotionName());
+		data.itemFlags = ItemFlags.CHANGED_TAGS;
+		data.setItemMeta(newMeta);
+	}
+
+	private static void copyMusicInfo(MusicInstrumentMeta musicMeta, ItemData data) {
+		MusicInstrumentMeta newMeta = (MusicInstrumentMeta) itemFactory.getItemMeta(data.type);
+		if (newMeta.equals(musicMeta))
+			return;
+		newMeta.setInstrument(musicMeta.getInstrument());
+		data.itemFlags = ItemFlags.CHANGED_TAGS;
+		data.setItemMeta(newMeta);
+	}
+
 	/**
 	 * Applies tags to this item.
 	 * @param tags Tags in Mojang's JSON format.

src/main/java/ch/njol/skript/aliases/ItemType.java

@@ -1616,15 +1616,28 @@ public Material getBlockMaterial() {
 	}
 
 	/**
-	 * Returns a base item type of this. Essentially, this calls
-	 * {@link ItemData#aliasCopy()} on all datas and creates a new type
+	 * Returns a base item type of this. i.e. an item type where all item datas only contain
+	 * the minimum ItemMeta info to represent the item, in the case of potions/goat horns.
 	 * containing the results.
 	 * @return Base item type.
 	 */
 	public ItemType getBaseType() {
 		ItemType copy = new ItemType();
 		for (ItemData data : types) {
-			copy.add_(data.aliasCopy());
+			copy.add_(data.getBaseCopy());
+		}
+		return copy;
+	}
+
+	/**
+	 * Returns a plain version of this item type, i.e. an item type where all item datas are plain and only contain
+	 * the minimum ItemMeta info to represent the item, in the case of potions/goat horns.
+	 * @return Plain item type.
+	 */
+	public ItemType getPlainType() {
+		ItemType copy = getBaseType();
+		for (ItemData data : copy.types) {
+			data.setPlain(true);
 		}
 		return copy;
 	}

src/main/java/ch/njol/skript/expressions/ExprPlain.java

@@ -1,7 +1,6 @@
 package ch.njol.skript.expressions;
 
 import ch.njol.skript.Skript;
-import ch.njol.skript.aliases.ItemData;
 import ch.njol.skript.aliases.ItemType;
 import ch.njol.skript.doc.Description;
 import ch.njol.skript.doc.Example;
@@ -12,9 +11,7 @@
 import ch.njol.skript.lang.SkriptParser.ParseResult;
 import ch.njol.skript.lang.util.SimpleExpression;
 import ch.njol.util.Kleenean;
-
 import org.bukkit.event.Event;
-import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.Nullable;
 
 @Name("Plain Item")
@@ -46,10 +43,7 @@ protected ItemType[] get(Event e) {
 		ItemType itemType = item.getSingle(e);
 		if (itemType == null)
 			return new ItemType[0];
-		ItemData data = new ItemData(itemType.getMaterial());
-		data.setPlain(true);
-		ItemType plain = new ItemType(data);
-		return new ItemType[]{plain};
+		return new ItemType[]{itemType.getPlainType()};
 	}
 
 	@Override

src/test/skript/tests/regressions/8144-type of retains enchants.sk

@@ -0,0 +1,8 @@
+test "type of has enchants":
+	set {_dirt} to dirt
+	set {_dirtSharp1} to dirt of sharpness 1
+	assert type of {_dirt} is dirt
+	assert type of {_dirtSharp1} is dirt with "type of enchanted item wasn't the base material"
+	assert {_dirt} is not {_dirtSharp1}
+	assert type of {_dirtSharp1} is not {_dirtSharp1} with "type of enchanted item retained enchants"
+	assert enchantments of type of {_dirtSharp1} is not set with "type of enchanted item retained enchants"