[1.21.x] TODOs and NBT cleanup for entities

patches/net/minecraft/client/multiplayer/ClientLevel.java.patch

@@ -61,7 +61,7 @@
 +        if (net.neoforged.neoforge.common.NeoForge.EVENT_BUS.post(new net.neoforged.neoforge.event.entity.EntityJoinLevelEvent(p_104741_, this)).isCanceled()) return;
          this.removeEntity(p_104741_.getId(), Entity.RemovalReason.DISCARDED);
          this.entityStorage.addEntity(p_104741_);
-+        p_104741_.onAddedToWorld();
++        p_104741_.onAddedToLevel();
      }
 
      public void removeEntity(int p_171643_, Entity.RemovalReason p_171644_) {
@@ -115,7 +115,7 @@
              p_171716_.unRide();
              ClientLevel.this.players.remove(p_171716_);
 +
-+            p_171716_.onRemovedFromWorld();
++            p_171716_.onRemovedFromLevel();
 +            net.neoforged.neoforge.common.NeoForge.EVENT_BUS.post(new net.neoforged.neoforge.event.entity.EntityLeaveLevelEvent(p_171716_, ClientLevel.this));
 +
 +            if (p_171716_.isMultipartEntity()) {

patches/net/minecraft/server/level/ServerLevel.java.patch

@@ -114,7 +114,7 @@
 
 -        this.entityManager.addNewEntity(p_8854_);
 +        this.entityManager.addNewEntityWithoutEvent(p_8854_);
-+        p_8854_.onAddedToWorld();
++        p_8854_.onAddedToLevel();
      }
 
      private boolean addEntity(Entity p_8873_) {
@@ -124,7 +124,7 @@
          } else {
 -            return this.entityManager.addNewEntity(p_8873_);
 +            if (this.entityManager.addNewEntity(p_8873_)) {
-+                p_8873_.onAddedToWorld();
++                p_8873_.onAddedToLevel();
 +                return true;
 +            } else {
 +                return false;
@@ -216,7 +216,7 @@
 
              p_143375_.updateDynamicGameEventListener(DynamicGameEventListener::remove);
 +
-+            p_143375_.onRemovedFromWorld();
++            p_143375_.onRemovedFromLevel();
 +            net.neoforged.neoforge.common.NeoForge.EVENT_BUS.post(new net.neoforged.neoforge.event.entity.EntityLeaveLevelEvent(p_143375_, ServerLevel.this));
          }
 

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

@@ -448,7 +448,7 @@
 
              this.levelCallback.onMove();
          }
-+        if (this.isAddedToWorld() && !this.level.isClientSide && !this.isRemoved()) this.level.getChunk((int) Math.floor(p_20344_) >> 4, (int) Math.floor(p_20346_) >> 4); // Forge - ensure target chunk is loaded.
++        if (this.isAddedToLevel() && !this.level.isClientSide && !this.isRemoved()) this.level.getChunk((int) Math.floor(p_20344_) >> 4, (int) Math.floor(p_20346_) >> 4); // Forge - ensure target chunk is loaded.
      }
 
      public void checkDespawn() {
@@ -502,16 +502,16 @@
 +     * allow guarantees that entity position changes will force a chunk load, avoiding
 +     * potential issues with entity desyncing and bad chunk data.
 +     */
-+    private boolean isAddedToWorld;
++    private boolean isAddedToLevel;
 +
 +    @Override
-+    public final boolean isAddedToWorld() { return this.isAddedToWorld; }
++    public final boolean isAddedToLevel() { return this.isAddedToLevel; }
 +
 +    @Override
-+    public void onAddedToWorld() { this.isAddedToWorld = true; }
++    public void onAddedToLevel() { this.isAddedToLevel = true; }
 +
 +    @Override
-+    public void onRemovedFromWorld() { this.isAddedToWorld = false; }
++    public void onRemovedFromLevel() { this.isAddedToLevel = false; }
 +
 +    // Neo: Helper method to stop an entity from being removed if already marked for removal
 +    @Override

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

@@ -164,12 +164,12 @@
 +
 +    /**
 +     * Marks this mob as being disallowed to spawn during {@link Level#addFreshEntity(Entity)}.<p>
-+     * @throws UnsupportedOperationException if this entity has already been {@link Entity#isAddedToWorld() added to the world}.
++     * @throws UnsupportedOperationException if this entity has already been {@link Entity#isAddedToLevel()} added to the level.
 +     * @apiNote Not public-facing API.
 +     */
 +    @org.jetbrains.annotations.ApiStatus.Internal
 +    public final void setSpawnCancelled(boolean cancel) {
-+        if (this.isAddedToWorld()) {
++        if (this.isAddedToLevel()) {
 +            throw new UnsupportedOperationException("Late invocations of Mob#setSpawnCancelled are not permitted.");
 +        }
 +        this.spawnCancelled = cancel;

patches/net/minecraft/world/level/entity/PersistentEntitySectionManager.java.patch

@@ -24,15 +24,15 @@
 -        p_157553_.forEach(p_157607_ -> this.addEntity((T)p_157607_, true));
 +        p_157553_.forEach(p_157607_ -> {
 +            this.addEntity(p_157607_, true);
-+            if (p_157607_ instanceof Entity entity) entity.onAddedToWorld();
++            if (p_157607_ instanceof Entity entity) entity.onAddedToLevel();
 +        });
      }
 
      public void addWorldGenChunkEntities(Stream<T> p_157560_) {
 -        p_157560_.forEach(p_157605_ -> this.addEntity((T)p_157605_, false));
 +        p_157560_.forEach(p_157605_ -> {
 +            this.addEntity(p_157605_, false);
-+            if (p_157605_ instanceof Entity entity) entity.onAddedToWorld();
++            if (p_157605_ instanceof Entity entity) entity.onAddedToLevel();
 +        });
      }
 
@@ -44,7 +44,7 @@
 -            chunkentities.getEntities().forEach(p_157593_ -> this.addEntity((T)p_157593_, true));
 +            chunkentities.getEntities().forEach(p_157593_ -> {
 +                this.addEntity(p_157593_, true);
-+                if (p_157593_ instanceof Entity entity) entity.onAddedToWorld();
++                if (p_157593_ instanceof Entity entity) entity.onAddedToLevel();
 +            });
              this.chunkLoadStatuses.put(chunkentities.getPos().toLong(), PersistentEntitySectionManager.ChunkLoadStatus.LOADED);
          }

src/main/java/net/neoforged/neoforge/common/extensions/IEntityExtension.java

@@ -39,12 +39,24 @@ private Entity self() {
         return (Entity) this;
     }
 
+    /**
+     * Deserialize from a compound tag.
+     * 
+     * @deprecated Use a data component/attachment to store info, or {@link Entity#load(CompoundTag)} as a replacement.
+     */
     @Override
+    @Deprecated(forRemoval = true, since = "21.0")
     default void deserializeNBT(HolderLookup.Provider provider, CompoundTag nbt) {
         self().load(nbt);
     }
 
+    /**
+     * Serialize metadata into a compound tag.
+     * 
+     * @deprecated Use a data component/attachment to store info. ({@link Entity#setData(AttachmentType, Object)})
+     */
     @Override
+    @Deprecated(forRemoval = true, since = "21.0")
     default CompoundTag serializeNBT(HolderLookup.Provider provider) {
         CompoundTag ret = new CompoundTag();
         String id = self().getEncodeId();
@@ -135,24 +147,17 @@ default MobCategory getClassification(boolean forSpawnCount) {
      *
      * @return True if this entity is being tracked by a world
      */
-    // TODO: rename in 1.19 to isAddedToLevel
-    boolean isAddedToWorld();
+    boolean isAddedToLevel();
 
     /**
-     * Called after the entity has been added to the world's
-     * ticking list. Can be overriden, but needs to call super
-     * to prevent MC-136995.
+     * Called after the entity has been added to the world's ticking list.
      */
-    // TODO: rename in 1.19 to onAddedToLevel
-    void onAddedToWorld();
+    void onAddedToLevel();
 
     /**
-     * Called after the entity has been removed to the world's
-     * ticking list. Can be overriden, but needs to call super
-     * to prevent MC-136995.
+     * Called after the entity has been removed to the world's ticking list.
      */
-    // TODO: rename in 1.19 to onRemovedFromLevel
-    void onRemovedFromWorld();
+    void onRemovedFromLevel();
 
     /**
      * Revives an entity that has been removed from a world.

src/main/java/net/neoforged/neoforge/event/EventHooks.java

@@ -275,7 +275,7 @@ public static boolean checkSpawnPositionSpawner(Mob mob, ServerLevelAccessor lev
      * var zombie = new Zombie(level);
      * zombie.finalizeSpawn(level, difficulty, spawnType, spawnData);
      * level.tryAddFreshEntityWithPassengers(zombie);
-     * if (zombie.isAddedToWorld()) {
+     * if (zombie.isAddedToLevel()) {
      *     // Do stuff with your new zombie
      * }
      * </pre>
@@ -288,7 +288,7 @@ public static boolean checkSpawnPositionSpawner(Mob mob, ServerLevelAccessor lev
      * var zombie = new Zombie(level);
      * EventHooks.finalizeMobSpawn(zombie, level, difficulty, spawnType, spawnData);
      * level.tryAddFreshEntityWithPassengers(zombie);
-     * if (zombie.isAddedToWorld()) {
+     * if (zombie.isAddedToLevel()) {
      *     // Do stuff with your new zombie
      * }
      * </pre>

src/main/java/net/neoforged/neoforge/event/entity/EntityEvent.java

@@ -118,7 +118,7 @@ public boolean didChunkChange() {
      *
      * <p><strong>Note:</strong> This event is fired from the {@code Entity} constructor, and therefore the entity instance
      * might not be fully initialized. Be cautious in using methods and fields from the instance, and check
-     * {@link Entity#isAddedToWorld()} or {@link Entity#firstTick}.
+     * {@link Entity#isAddedToLevel()} or {@link Entity#firstTick}.
      *
      * <p>This event is not {@linkplain net.neoforged.bus.api.ICancellableEvent cancellable}, and is fired on the
      * {@linkplain NeoForge#EVENT_BUS game event bus}.