Fixes shearing leads for custom shears (interacting with entity & leash knot) (#10706)

patches/minecraft/net/minecraft/world/entity/Entity.java.patch

@@ -238,7 +238,12 @@
              p_409579_.addFreshEntity(itementity);
              return itementity;
          }
-@@ -2127,7 +_,7 @@
+@@ -2123,11 +_,11 @@
+         }
+ 
+         ItemStack itemstack = p_19978_.getItemInHand(p_19979_);
+-        if (itemstack.is(Items.SHEARS) && this.shearOffAllLeashConnections(p_19978_)) {
++        if (itemstack.canPerformAction(net.minecraftforge.common.ToolActions.SHEARS_HARVEST) && this.shearOffAllLeashConnections(p_19978_)) {
              itemstack.hurtAndBreak(1, p_19978_, p_19979_);
              return InteractionResult.SUCCESS;
          } else if (this instanceof Mob mob

patches/minecraft/net/minecraft/world/entity/decoration/LeashFenceKnotEntity.java.patch

@@ -0,0 +1,11 @@
+--- a/net/minecraft/world/entity/decoration/LeashFenceKnotEntity.java
++++ b/net/minecraft/world/entity/decoration/LeashFenceKnotEntity.java
+@@ -72,7 +_,7 @@
+         if (this.level().isClientSide) {
+             return InteractionResult.SUCCESS;
+         } else {
+-            if (p_31842_.getItemInHand(p_31843_).is(Items.SHEARS)) {
++            if (p_31842_.getItemInHand(p_31843_).canPerformAction(net.minecraftforge.common.ToolActions.SHEARS_HARVEST)) {
+                 InteractionResult interactionresult = super.interact(p_31842_, p_31843_);
+                 if (interactionresult instanceof InteractionResult.Success interactionresult$success && interactionresult$success.wasItemInteraction()) {
+                     return interactionresult;

src/test/generated/shears_behavior/data/forge/test_instance/shears_behavior/custom_shears_unleash_entity.json

@@ -0,0 +1,7 @@
+{
+  "type": "minecraft:function",
+  "environment": "minecraft:default",
+  "function": "forge:shears_behavior/custom_shears_unleash_entity",
+  "max_ticks": 100,
+  "structure": "forge:empty3x3x3"
+}

src/test/generated/shears_behavior/data/forge/test_instance/shears_behavior/custom_shears_unleash_knot.json

@@ -0,0 +1,7 @@
+{
+  "type": "minecraft:function",
+  "environment": "minecraft:default",
+  "function": "forge:shears_behavior/custom_shears_unleash_knot",
+  "max_ticks": 100,
+  "structure": "forge:empty3x3x3"
+}

src/test/java/net/minecraftforge/debug/gameplay/item/ShearsBehaviorTest.java

@@ -0,0 +1,110 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
+package net.minecraftforge.debug.gameplay.item;
+
+import net.minecraft.core.BlockPos;
+import net.minecraft.gametest.framework.GameTestHelper;
+import net.minecraft.world.InteractionHand;
+import net.minecraft.world.entity.EntityType;
+import net.minecraft.world.entity.decoration.LeashFenceKnotEntity;
+import net.minecraft.world.item.Item;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.Items;
+import net.minecraft.world.level.GameType;
+import net.minecraft.world.level.block.Blocks;
+import net.minecraftforge.common.ToolAction;
+import net.minecraftforge.common.ToolActions;
+import net.minecraftforge.fml.common.Mod;
+import net.minecraftforge.fml.javafmlmod.FMLJavaModLoadingContext;
+import net.minecraftforge.gametest.GameTest;
+import net.minecraftforge.gametest.GameTestNamespace;
+import net.minecraftforge.registries.DeferredRegister;
+import net.minecraftforge.registries.ForgeRegistries;
+import net.minecraftforge.registries.RegistryObject;
+import net.minecraftforge.test.BaseTestMod;
+
+@Mod(ShearsBehaviorTest.MOD_ID)
+@GameTestNamespace("forge")
+public class ShearsBehaviorTest extends BaseTestMod {
+    public static final String MOD_ID = "shears_behavior";
+
+    private static final DeferredRegister<Item> ITEMS = DeferredRegister.create(ForgeRegistries.ITEMS, MOD_ID);
+    private static final RegistryObject<Item> CUSTOM_SHEARS_HARVEST_ITEM = ITEMS.register("custom_shears_harvest_item", () -> new ShearsHarvestItem(
+            new Item.Properties().stacksTo(1).setId(ITEMS.key("custom_shears_harvest_item"))
+    ));
+
+    public ShearsBehaviorTest(FMLJavaModLoadingContext context) {
+        super(context, false, true);
+        this.testItem(lookup -> CUSTOM_SHEARS_HARVEST_ITEM.get().getDefaultInstance());
+    }
+
+    @GameTest
+    public static void custom_shears_unleash_entity(GameTestHelper helper) {
+        helper.makeFloor();
+
+        // setup: fence + knot + leash cow
+        var fencePos = new BlockPos(1, 1, 1);
+        var cowPos = new BlockPos(0, 1, 1);
+        helper.setBlock(fencePos, Blocks.OAK_FENCE);
+        var cow = helper.spawnWithNoFreeWill(EntityType.COW, cowPos);
+        var knot = LeashFenceKnotEntity.getOrCreateKnot(helper.getLevel(), helper.absolutePos(fencePos));
+        cow.setLeashedTo(knot, true);
+        helper.assertTrue(cow.isLeashed(), "Cow should start leashed");
+
+        // act: interact with cow using custom shears
+        var player = helper.makeMockPlayer(GameType.SURVIVAL);
+        var shears = CUSTOM_SHEARS_HARVEST_ITEM.get().getDefaultInstance();
+        player.setItemInHand(InteractionHand.MAIN_HAND, shears);
+        var result = player.interactOn(cow, InteractionHand.MAIN_HAND);
+
+        // assert
+        helper.assertTrue(result.consumesAction(), "Using custom shears on leashed cow should result in consume action");
+        helper.assertTrue(!cow.isLeashed(), "Cow should be unleashed by custom shears");
+        helper.assertItemEntityPresent(Items.LEAD);
+
+        helper.succeed();
+    }
+
+
+    @GameTest
+    public static void custom_shears_unleash_knot(GameTestHelper helper) {
+        helper.makeFloor();
+
+        // setup: fence + knot + leash cow
+        var fencePos = new BlockPos(1, 1, 1);
+        var cowPos = new BlockPos(0, 1, 1);
+        helper.setBlock(fencePos, Blocks.OAK_FENCE);
+        var cow = helper.spawnWithNoFreeWill(EntityType.COW, cowPos);
+        var knot = LeashFenceKnotEntity.getOrCreateKnot(helper.getLevel(), helper.absolutePos(fencePos));
+        cow.setLeashedTo(knot, true);
+        helper.assertTrue(cow.isLeashed(), "Cow should start leashed");
+
+        // act: interact with knot using custom shears
+        var player = helper.makeMockPlayer(GameType.SURVIVAL);
+        var shears = CUSTOM_SHEARS_HARVEST_ITEM.get().getDefaultInstance();
+        player.setItemInHand(InteractionHand.MAIN_HAND, shears);
+        var result = player.interactOn(knot, InteractionHand.MAIN_HAND);
+
+        // assert
+        helper.assertTrue(result.consumesAction(), "Using custom shears on leash knot should result in consume action");
+        helper.assertTrue(!cow.isLeashed(), "Cow should be unleashed by sheared knot");
+        helper.assertItemEntityPresent(Items.LEAD);
+
+        helper.succeed();
+    }
+
+    private static final class ShearsHarvestItem extends Item {
+        ShearsHarvestItem(Item.Properties properties) {
+            super(properties);
+        }
+
+        @Override
+        public boolean canPerformAction(ItemStack stack, ToolAction action) {
+            return action == ToolActions.SHEARS_HARVEST;
+        }
+    }
+
+}