From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jake Potrebic <jake.m.potrebic@gmail.com>
Date: Sat, 15 May 2021 22:11:11 -0700
Subject: [PATCH] ItemStack repair check API


diff --git a/src/main/java/net/minecraft/world/item/Item.java b/src/main/java/net/minecraft/world/item/Item.java
index f7758ee4aa8bbb31a80ec2e331b3fd3c55069808..7c9ef73983c2c7f4b7386a472e5a79dce7fa7ea7 100644
--- a/src/main/java/net/minecraft/world/item/Item.java
+++ b/src/main/java/net/minecraft/world/item/Item.java
@@ -269,6 +269,7 @@ public class Item implements IMaterial {
         return this.i;
     }
 
+    public boolean canRepair(ItemStack toBeRepaired, ItemStack repairMaterial) { return a(toBeRepaired, repairMaterial); } // Paper - OBFHELPER
     public boolean a(ItemStack itemstack, ItemStack itemstack1) {
         return false;
     }
diff --git a/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java b/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java
index 697949abbe662a55fc31ad811863717e35b9d1b6..a386beea01056a7fb448596ba45342d832a4c63d 100644
--- a/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java
+++ b/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java
@@ -487,6 +487,14 @@ public final class CraftMagicNumbers implements UnsafeValues {
         return io.papermc.paper.inventory.ItemRarity.values()[getItem(itemStack.getType()).getItemStackRarity(CraftItemStack.asNMSCopy(itemStack)).ordinal()];
     }
 
+    @Override
+    public boolean isValidRepairItemStack(org.bukkit.inventory.ItemStack itemToBeRepaired, org.bukkit.inventory.ItemStack repairMaterial) {
+        if (!itemToBeRepaired.getType().isItem() || !repairMaterial.getType().isItem()) {
+            return false;
+        }
+        return this.getItem(itemToBeRepaired.getType()).canRepair(CraftItemStack.asNMSCopy(itemToBeRepaired), CraftItemStack.asNMSCopy(repairMaterial));
+    }
+
     @Override
     public int getProtocolVersion() {
         return net.minecraft.SharedConstants.getGameVersion().getProtocolVersion();
diff --git a/src/test/java/io/papermc/paper/util/ItemStackRepairCheckTest.java b/src/test/java/io/papermc/paper/util/ItemStackRepairCheckTest.java
new file mode 100644
index 0000000000000000000000000000000000000000..8d9c9b3bd53d407391d4fcb7fc773153d1a7b402
--- /dev/null
+++ b/src/test/java/io/papermc/paper/util/ItemStackRepairCheckTest.java
@@ -0,0 +1,48 @@
+package io.papermc.paper.util;
+
+import org.bukkit.Material;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.support.AbstractTestingBase;
+import org.junit.Test;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertThrows;
+import static org.junit.Assert.assertTrue;
+
+public class ItemStackRepairCheckTest extends AbstractTestingBase {
+
+    @Test
+    public void testIsRepariableBy() {
+        ItemStack diamondPick = new ItemStack(Material.DIAMOND_PICKAXE);
+
+        assertTrue("diamond pick isn't repairable by a diamond", diamondPick.isRepairableBy(new ItemStack(Material.DIAMOND)));
+    }
+
+    @Test
+    public void testCanRepair() {
+        ItemStack diamond = new ItemStack(Material.DIAMOND);
+
+        assertTrue("diamond can't repair a diamond axe", diamond.canRepair(new ItemStack(Material.DIAMOND_AXE)));
+    }
+
+    @Test
+    public void testIsNotRepairableBy() {
+        ItemStack notDiamondPick = new ItemStack(Material.ACACIA_SAPLING);
+
+        assertFalse("acacia sapling is repairable by a diamond", notDiamondPick.isRepairableBy(new ItemStack(Material.DIAMOND)));
+    }
+
+    @Test
+    public void testCanNotRepair() {
+        ItemStack diamond = new ItemStack(Material.DIAMOND);
+
+        assertFalse("diamond can repair oak button", diamond.canRepair(new ItemStack(Material.OAK_BUTTON)));
+    }
+
+    @Test
+    public void testInvalidItem() {
+        ItemStack badItemStack = new ItemStack(Material.ACACIA_WALL_SIGN);
+
+        assertFalse("acacia wall sign is repairable by diamond", badItemStack.isRepairableBy(new ItemStack(Material.DIAMOND)));
+    }
+}