From 121534e8412df119ba2c7f462d52f79b5827935a 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

---
 .../craftbukkit/util/CraftMagicNumbers.java   |  8 ++++
 .../paper/util/ItemStackRepairCheckTest.java  | 41 +++++++++++++++++++
 2 files changed, 49 insertions(+)
 create mode 100644 paper-server/src/test/java/io/papermc/paper/util/ItemStackRepairCheckTest.java

diff --git a/paper-server/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java b/paper-server/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java
index 30f2ddb663..fa4e8cb2d5 100644
--- a/paper-server/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java
+++ b/paper-server/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java
@@ -548,6 +548,14 @@ public final class CraftMagicNumbers implements UnsafeValues {
     public int getProtocolVersion() {
         return net.minecraft.SharedConstants.getCurrentVersion().getProtocolVersion();
     }
+
+    @Override
+    public boolean isValidRepairItemStack(org.bukkit.inventory.ItemStack itemToBeRepaired, org.bukkit.inventory.ItemStack repairMaterial) {
+        if (!itemToBeRepaired.getType().isItem() || !repairMaterial.getType().isItem()) {
+            return false;
+        }
+        return CraftItemStack.unwrap(itemToBeRepaired).isValidRepairItem(CraftItemStack.unwrap(repairMaterial));
+    }
     // Paper end
 
     /**
diff --git a/paper-server/src/test/java/io/papermc/paper/util/ItemStackRepairCheckTest.java b/paper-server/src/test/java/io/papermc/paper/util/ItemStackRepairCheckTest.java
new file mode 100644
index 0000000000..04e2568816
--- /dev/null
+++ b/paper-server/src/test/java/io/papermc/paper/util/ItemStackRepairCheckTest.java
@@ -0,0 +1,41 @@
+package io.papermc.paper.util;
+
+import org.bukkit.Material;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.support.environment.VanillaFeature;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+@VanillaFeature
+public class ItemStackRepairCheckTest {
+
+    @Test
+    public void testIsRepariableBy() {
+        ItemStack diamondPick = new ItemStack(Material.DIAMOND_PICKAXE);
+
+        assertTrue(diamondPick.isRepairableBy(new ItemStack(Material.DIAMOND)), "diamond pick isn't repairable by a diamond");
+    }
+
+    @Test
+    public void testCanRepair() {
+        ItemStack diamond = new ItemStack(Material.DIAMOND);
+
+        assertTrue(diamond.canRepair(new ItemStack(Material.DIAMOND_AXE)), "diamond can't repair a diamond axe");
+    }
+
+    @Test
+    public void testIsNotRepairableBy() {
+        ItemStack notDiamondPick = new ItemStack(Material.ACACIA_SAPLING);
+
+        assertFalse(notDiamondPick.isRepairableBy(new ItemStack(Material.DIAMOND)), "acacia sapling is repairable by a diamond");
+    }
+
+    @Test
+    public void testCanNotRepair() {
+        ItemStack diamond = new ItemStack(Material.DIAMOND);
+
+        assertFalse(diamond.canRepair(new ItemStack(Material.OAK_BUTTON)), "diamond can repair oak button");
+    }
+}