Fix Invalid Equipment Slots in CondIsWearing

src/main/java/ch/njol/skript/conditions/CondIsWearing.java

@@ -1,5 +1,6 @@
 package ch.njol.skript.conditions;
 
+import ch.njol.skript.Skript;
 import ch.njol.skript.aliases.ItemType;
 import ch.njol.skript.conditions.base.PropertyCondition;
 import ch.njol.skript.conditions.base.PropertyCondition.PropertyType;
@@ -12,7 +13,7 @@
 import ch.njol.skript.lang.SkriptParser.ParseResult;
 import ch.njol.skript.lang.util.SimpleExpression;
 import ch.njol.util.Kleenean;
-import org.bukkit.entity.LivingEntity;
+import org.bukkit.entity.*;
 import org.bukkit.event.Event;
 import org.bukkit.inventory.EntityEquipment;
 import org.bukkit.inventory.EquipmentSlot;
@@ -30,6 +31,9 @@
 })
 @Since("1.0")
 public class CondIsWearing extends Condition {
+
+	private static final boolean HAS_CAN_USE_SLOT_METHOD = Skript.methodExists(LivingEntity.class, "canUseEquipmentSlot", EquipmentSlot.class);
+	private static final boolean HAS_BODY_SLOT = Skript.fieldExists(EquipmentSlot.class, "BODY");
 
 	static {
 		PropertyCondition.register(CondIsWearing.class, "wearing %itemtypes%", "livingentities");
@@ -59,6 +63,21 @@ public boolean check(Event event) {
 				return false; // spigot nullability, no identifier as to why this occurs
 
 			ItemStack[] contents = Arrays.stream(EquipmentSlot.values())
+				.filter(slot -> {
+					// this method was added in 1.20.6
+					if (HAS_CAN_USE_SLOT_METHOD)
+						return entity.canUseEquipmentSlot(slot);
+
+					// body slot was added in 1.20.5
+					if (HAS_BODY_SLOT && slot == EquipmentSlot.BODY)
+						// this may change in the future, but for now this is the only way to figure out
+						// if the entity can use the body slot
+						return entity instanceof Horse
+							|| entity instanceof Wolf
+							|| entity instanceof Llama;
+
+					return true;
+				})
 				.map(equipment::getItem)
 				.toArray(ItemStack[]::new);
 

src/test/java/org/skriptlang/skript/test/tests/regression/MissingCheckIfEntityCanUseSlot7524Test.java

@@ -0,0 +1,64 @@
+package org.skriptlang.skript.test.tests.regression;
+
+import ch.njol.skript.Skript;
+import ch.njol.skript.lang.Condition;
+import ch.njol.skript.lang.util.ContextlessEvent;
+import ch.njol.skript.test.runner.SkriptJUnitTest;
+import ch.njol.skript.variables.Variables;
+import org.bukkit.Material;
+import org.bukkit.entity.LivingEntity;
+import org.bukkit.entity.Player;
+import org.bukkit.inventory.EntityEquipment;
+import org.bukkit.inventory.EquipmentSlot;
+import org.bukkit.inventory.ItemStack;
+import org.easymock.EasyMock;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+public class MissingCheckIfEntityCanUseSlot7524Test extends SkriptJUnitTest {
+
+	private static final boolean HAS_CAN_USE_SLOT_METHOD = Skript.methodExists(LivingEntity.class, "canUseEquipmentSlot", EquipmentSlot.class);
+
+	private Player player;
+	private EntityEquipment equipment;
+	private Condition isWearingCondition;
+
+	@Before
+	public void setup() {
+		player = EasyMock.niceMock(Player.class);
+		equipment = EasyMock.niceMock(EntityEquipment.class);
+
+		isWearingCondition = Condition.parse("{_player} is wearing diamond chestplate", null);
+		if (isWearingCondition == null)
+			throw new IllegalStateException();
+	}
+
+	@Test
+	public void test() {
+		ContextlessEvent event = ContextlessEvent.get();
+		Variables.setVariable("player", player, event, true);
+
+		EasyMock.expect(player.isValid()).andStubReturn(true);
+		EasyMock.expect(player.getEquipment()).andReturn(equipment);
+
+		if (HAS_CAN_USE_SLOT_METHOD) {
+			EasyMock.expect(player.canUseEquipmentSlot(EquipmentSlot.CHEST)).andReturn(true);
+			EasyMock.expect(player.canUseEquipmentSlot(EquipmentSlot.LEGS)).andReturn(true);
+			EasyMock.expect(player.canUseEquipmentSlot(EquipmentSlot.FEET)).andReturn(true);
+			EasyMock.expect(player.canUseEquipmentSlot(EquipmentSlot.HEAD)).andReturn(true);
+			EasyMock.expect(player.canUseEquipmentSlot(EquipmentSlot.HAND)).andReturn(true);
+			EasyMock.expect(player.canUseEquipmentSlot(EquipmentSlot.OFF_HAND)).andReturn(true);
+			EasyMock.expect(player.canUseEquipmentSlot(EquipmentSlot.BODY)).andReturn(false);
+		}
+
+		EasyMock.expect(equipment.getItem(EquipmentSlot.CHEST)).andReturn(new ItemStack(Material.DIAMOND_CHESTPLATE));
+
+		EasyMock.replay(player, equipment);
+
+		assert isWearingCondition.check(event);
+
+		EasyMock.verify(player, equipment);
+	}
+
+}