From 25b143484c19bea2a14937264832f7cf74fc497c Mon Sep 17 00:00:00 2001
From: i509VCB <git@i509.me>
Date: Mon, 26 Oct 2020 15:57:02 -0500
Subject: [PATCH] Tweak entity type builder generics to eliminate explicit type
 arguments (#1094)

* Tweak entity type builder generics to eliminate explicit type arguments

* Apply different generic on the entity factory method
---
 .../v1/entity/FabricEntityTypeBuilder.java    | 14 ++--
 .../EntityTypeBuilderGenericsTest.java        | 84 +++++++++++++++++++
 2 files changed, 91 insertions(+), 7 deletions(-)
 create mode 100644 fabric-object-builder-api-v1/src/testmod/java/net/fabricmc/fabric/test/object/builder/EntityTypeBuilderGenericsTest.java

diff --git a/fabric-object-builder-api-v1/src/main/java/net/fabricmc/fabric/api/object/builder/v1/entity/FabricEntityTypeBuilder.java b/fabric-object-builder-api-v1/src/main/java/net/fabricmc/fabric/api/object/builder/v1/entity/FabricEntityTypeBuilder.java
index bda6b25f1..ec29eb4e8 100644
--- a/fabric-object-builder-api-v1/src/main/java/net/fabricmc/fabric/api/object/builder/v1/entity/FabricEntityTypeBuilder.java
+++ b/fabric-object-builder-api-v1/src/main/java/net/fabricmc/fabric/api/object/builder/v1/entity/FabricEntityTypeBuilder.java
@@ -136,10 +136,10 @@ public class FabricEntityTypeBuilder<T extends Entity> {
 		return this;
 	}
 
-	public FabricEntityTypeBuilder<T> entityFactory(EntityType.EntityFactory<T> factory) {
+	public <N extends T> FabricEntityTypeBuilder<N> entityFactory(EntityType.EntityFactory<N> factory) {
 		Objects.requireNonNull(factory, "Entity Factory cannot be null");
-		this.factory = factory;
-		return this;
+		this.factory = (EntityType.EntityFactory<T>) factory;
+		return (FabricEntityTypeBuilder<N>) this;
 	}
 
 	/**
@@ -289,9 +289,9 @@ public class FabricEntityTypeBuilder<T extends Entity> {
 		}
 
 		@Override
-		public FabricEntityTypeBuilder.Living<T> entityFactory(EntityType.EntityFactory<T> factory) {
+		public <N extends T> FabricEntityTypeBuilder.Living<N> entityFactory(EntityType.EntityFactory<N> factory) {
 			super.entityFactory(factory);
-			return this;
+			return (Living<N>) this;
 		}
 
 		@Override
@@ -429,9 +429,9 @@ public class FabricEntityTypeBuilder<T extends Entity> {
 		}
 
 		@Override
-		public FabricEntityTypeBuilder.Mob<T> entityFactory(EntityType.EntityFactory<T> factory) {
+		public <N extends T> FabricEntityTypeBuilder.Mob<N> entityFactory(EntityType.EntityFactory<N> factory) {
 			super.entityFactory(factory);
-			return this;
+			return (Mob<N>) this;
 		}
 
 		@Override
diff --git a/fabric-object-builder-api-v1/src/testmod/java/net/fabricmc/fabric/test/object/builder/EntityTypeBuilderGenericsTest.java b/fabric-object-builder-api-v1/src/testmod/java/net/fabricmc/fabric/test/object/builder/EntityTypeBuilderGenericsTest.java
new file mode 100644
index 000000000..121a0aae7
--- /dev/null
+++ b/fabric-object-builder-api-v1/src/testmod/java/net/fabricmc/fabric/test/object/builder/EntityTypeBuilderGenericsTest.java
@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2016, 2017, 2018, 2019 FabricMC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.fabricmc.fabric.test.object.builder;
+
+import java.util.Collections;
+
+import net.minecraft.entity.Entity;
+import net.minecraft.entity.EntityType;
+import net.minecraft.entity.EquipmentSlot;
+import net.minecraft.entity.LivingEntity;
+import net.minecraft.entity.SpawnGroup;
+import net.minecraft.entity.mob.MobEntity;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.Arm;
+import net.minecraft.world.World;
+
+import net.fabricmc.fabric.api.object.builder.v1.entity.FabricEntityTypeBuilder;
+
+// This test is intentionally not an entrypoint to verify the generics of the entity type builder propagate properly
+final class EntityTypeBuilderGenericsTest {
+	static EntityType<Entity> ENTITY_1 = FabricEntityTypeBuilder.create().build();
+	static EntityType<LivingEntity> LIVING_ENTITY_1 = FabricEntityTypeBuilder.createLiving().build();
+	static EntityType<TestEntity> TEST_ENTITY_1 = FabricEntityTypeBuilder.createLiving()
+			.entityFactory(TestEntity::new)
+			.spawnGroup(SpawnGroup.CREATURE)
+			.build();
+	static EntityType<TestEntity> OLD_TEST = FabricEntityTypeBuilder.<TestEntity>createLiving()
+			.entityFactory(TestEntity::new)
+			.spawnGroup(SpawnGroup.CREATURE)
+			.build();
+	static EntityType<TestMob> OLD_MOB = FabricEntityTypeBuilder.<TestMob>createMob()
+			.disableSaving()
+			.entityFactory(TestMob::new)
+			.build();
+	static EntityType<TestMob> MOB_TEST = FabricEntityTypeBuilder.createMob()
+			.disableSaving()
+			.entityFactory(TestMob::new)
+			.build();
+
+	private static class TestEntity extends LivingEntity {
+		protected TestEntity(EntityType<? extends LivingEntity> entityType, World world) {
+			super(entityType, world);
+		}
+
+		@Override
+		public Iterable<ItemStack> getArmorItems() {
+			return Collections.emptyList();
+		}
+
+		@Override
+		public ItemStack getEquippedStack(EquipmentSlot slot) {
+			return ItemStack.EMPTY;
+		}
+
+		@Override
+		public void equipStack(EquipmentSlot slot, ItemStack stack) {
+		}
+
+		@Override
+		public Arm getMainArm() {
+			return Arm.RIGHT;
+		}
+	}
+
+	private static class TestMob extends MobEntity {
+		protected TestMob(EntityType<? extends MobEntity> entityType, World world) {
+			super(entityType, world);
+		}
+	}
+}