Add AnvilView#bypassEnchantmentLevelRestriction

Anvils, by default, limit applied enchantment levels to their respective
maximum level. The added API enables plugins to disable this behaviour,
allowing enchantments that are overleveled to be applied via the anvil.

paper-server/patches/sources/net/minecraft/world/inventory/AnvilMenu.java.patch

@@ -11,7 +11,7 @@
  public class AnvilMenu extends ItemCombinerMenu {
  
      public static final int INPUT_SLOT = 0;
-@@ -45,6 +49,11 @@
+@@ -45,6 +49,12 @@
      private static final int ADDITIONAL_SLOT_X_PLACEMENT = 76;
      private static final int RESULT_SLOT_X_PLACEMENT = 134;
      private static final int SLOT_Y_PLACEMENT = 47;
@@ -20,10 +20,11 @@
 +    public int maximumRepairCost = 40;
 +    private CraftAnvilView bukkitEntity;
 +    // CraftBukkit end
++    public boolean bypassEnchantmentLevelRestriction = false; // Paper - bypass anvil level restrictions
  
      public AnvilMenu(int syncId, Inventory inventory) {
          this(syncId, inventory, ContainerLevelAccess.NULL);
-@@ -72,7 +81,7 @@
+@@ -72,7 +82,7 @@
  
      @Override
      protected boolean mayPickup(Player player, boolean present) {
@@ -32,7 +33,7 @@
      }
  
      @Override
-@@ -94,7 +103,7 @@
+@@ -94,7 +104,7 @@
              this.inputSlots.setItem(1, ItemStack.EMPTY);
          }
  
@@ -41,7 +42,7 @@
          this.inputSlots.setItem(0, ItemStack.EMPTY);
          this.access.execute((world, blockposition) -> {
              BlockState iblockdata = world.getBlockState(blockposition);
-@@ -102,6 +111,16 @@
+@@ -102,6 +112,16 @@
              if (!player.hasInfiniteMaterials() && iblockdata.is(BlockTags.ANVIL) && player.getRandom().nextFloat() < 0.12F) {
                  BlockState iblockdata1 = AnvilBlock.damage(iblockdata);
  
@@ -58,7 +59,7 @@
                  if (iblockdata1 == null) {
                      world.removeBlock(blockposition, false);
                      world.levelEvent(1029, blockposition, 0);
-@@ -143,8 +162,8 @@
+@@ -143,8 +163,8 @@
                  if (itemstack1.isDamageableItem() && itemstack.isValidRepairItem(itemstack2)) {
                      k = Math.min(itemstack1.getDamageValue(), itemstack1.getMaxDamage() / 4);
                      if (k <= 0) {
@@ -69,7 +70,7 @@
                          return;
                      }
  
-@@ -158,8 +177,8 @@
+@@ -158,8 +178,8 @@
                      this.repairItemCountCost = i1;
                  } else {
                      if (!flag && (!itemstack1.is(itemstack2.getItem()) || !itemstack1.isDamageableItem())) {
@@ -80,7 +81,16 @@
                          return;
                      }
  
-@@ -233,8 +252,8 @@
+@@ -214,7 +234,7 @@
+                             flag2 = true;
+                         } else {
+                             flag1 = true;
+-                            if (i2 > enchantment.getMaxLevel()) {
++                            if (i2 > enchantment.getMaxLevel() && !this.bypassEnchantmentLevelRestriction) { // Paper - bypass anvil level restrictions
+                                 i2 = enchantment.getMaxLevel();
+                             }
+ 
+@@ -233,8 +253,8 @@
                      }
  
                      if (flag2 && !flag1) {
@@ -91,7 +101,7 @@
                          return;
                      }
                  }
-@@ -260,14 +279,14 @@
+@@ -260,14 +280,14 @@
              }
  
              if (b0 == i && b0 > 0) {
@@ -109,7 +119,7 @@
                  itemstack1 = ItemStack.EMPTY;
              }
  
-@@ -285,12 +304,13 @@
+@@ -285,12 +305,13 @@
                  EnchantmentHelper.setEnchantments(itemstack1, itemenchantments_a.toImmutable());
              }
  
@@ -126,7 +136,7 @@
      }
  
      public static int calculateIncreasedRepairCost(int cost) {
-@@ -313,6 +333,7 @@
+@@ -313,6 +334,7 @@
              }
  
              this.createResult();
@@ -134,7 +144,7 @@
              return true;
          } else {
              return false;
-@@ -329,4 +350,19 @@
+@@ -329,4 +351,19 @@
      public int getCost() {
          return this.cost.get();
      }

paper-server/src/main/java/org/bukkit/craftbukkit/inventory/view/CraftAnvilView.java

@@ -50,6 +50,18 @@ public class CraftAnvilView extends CraftInventoryView<AnvilMenu, AnvilInventory
         this.container.maximumRepairCost = cost;
     }
 
+    // Paper start
+    @Override
+    public boolean bypassesEnchantmentLevelRestriction() {
+        return this.container.bypassEnchantmentLevelRestriction;
+    }
+
+    @Override
+    public void bypassEnchantmentLevelRestriction(final boolean bypassEnchantmentLevelRestriction) {
+        this.container.bypassEnchantmentLevelRestriction = bypassEnchantmentLevelRestriction;
+    }
+    // Paper end
+
     public void updateFromLegacy(CraftInventoryAnvil legacy) {
         if (legacy.isRepairCostSet()) {
             this.setRepairCost(legacy.getRepairCost());