1 files changed, 129 insertions, 0 deletions
diff --git a/patches/server/0239-Add-Debug-Entities-option-to-debug-dupe-uuid-issues.patch b/patches/server/0239-Add-Debug-Entities-option-to-debug-dupe-uuid-issues.patch
new file mode 100644
index 0000000000..5183fa7c7a
--- /dev/null
+++ b/patches/server/0239-Add-Debug-Entities-option-to-debug-dupe-uuid-issues.patch
@@ -0,0 +1,129 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Aikar <[email protected]>
+Date: Sat, 21 Jul 2018 08:25:40 -0400
+Subject: [PATCH] Add Debug Entities option to debug dupe uuid issues
+
+Add -Ddebug.entities=true to your JVM flags to gain more information
+
+1.17: Needs to be reworked for new entity storage system
+
+diff --git a/src/main/java/net/minecraft/server/level/ChunkMap.java b/src/main/java/net/minecraft/server/level/ChunkMap.java
+index ea9f536efd4c76b421f6e02f93f16fae115840d8..d1af0aca0237ee86acd86fea3255ddeadc3db0d6 100644
+--- a/src/main/java/net/minecraft/server/level/ChunkMap.java
++++ b/src/main/java/net/minecraft/server/level/ChunkMap.java
+@@ -886,6 +886,7 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider
+                 } else {
+                     ChunkMap.TrackedEntity playerchunkmap_entitytracker = new ChunkMap.TrackedEntity(entity, i, j, entitytypes.trackDeltas());
+ 
++                    entity.tracker = playerchunkmap_entitytracker; // Paper - Fast access to tracker
+                     this.entityMap.put(entity.getId(), playerchunkmap_entitytracker);
+                     playerchunkmap_entitytracker.updatePlayers(this.level.players());
+                     if (entity instanceof ServerPlayer) {
+@@ -928,7 +929,7 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider
+         if (playerchunkmap_entitytracker1 != null) {
+             playerchunkmap_entitytracker1.broadcastRemoved();
+         }
+-
++        entity.tracker = null; // Paper - We're no longer tracked
+     }
+ 
+     protected void tick() {
+diff --git a/src/main/java/net/minecraft/server/level/ServerLevel.java b/src/main/java/net/minecraft/server/level/ServerLevel.java
+index 6ad79090c0c186394f1635d420884a5b34c7c952..f85692e588c022a1f0cc5e3cde001d968eea59c8 100644
+--- a/src/main/java/net/minecraft/server/level/ServerLevel.java
++++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
+@@ -216,6 +216,9 @@ public class ServerLevel extends Level implements WorldGenLevel {
+     public final LevelStorageSource.LevelStorageAccess convertable;
+     public final UUID uuid;
+     public boolean hasPhysicsEvent = true; // Paper
++    public static Throwable getAddToWorldStackTrace(Entity entity) {
++        return new Throwable(entity + " Added to world at " + new java.util.Date());
++    }
+ 
+     @Override public LevelChunk getChunkIfLoaded(int x, int z) { // Paper - this was added in world too but keeping here for NMS ABI
+         return this.chunkSource.getChunk(x, z, false);
+@@ -1232,7 +1235,28 @@ public class ServerLevel extends Level implements WorldGenLevel {
+     // CraftBukkit start
+     private boolean addEntity(Entity entity, CreatureSpawnEvent.SpawnReason spawnReason) {
+         org.spigotmc.AsyncCatcher.catchOp("entity add"); // Spigot
++        // Paper start
++        if (entity.valid) {
++            MinecraftServer.LOGGER.error("Attempted Double World add on " + entity, new Throwable());
++
++            if (DEBUG_ENTITIES) {
++                Throwable thr = entity.addedToWorldStack;
++                if (thr == null) {
++                    MinecraftServer.LOGGER.error("Double add entity has no add stacktrace");
++                } else {
++                    MinecraftServer.LOGGER.error("Double add stacktrace: ", thr);
++                }
++            }
++            return true;
++        }
++        // Paper end
+         if (entity.isRemoved()) {
++            // Paper start
++            if (DEBUG_ENTITIES) {
++                new Throwable("Tried to add entity " + entity + " but it was marked as removed already").printStackTrace(); // CraftBukkit
++                getAddToWorldStackTrace(entity).printStackTrace();
++            }
++            // Paper end
+             // WorldServer.LOGGER.warn("Tried to add entity {} but it was marked as removed already", EntityTypes.getKey(entity.getType())); // CraftBukkit
+             return false;
+         } else {
+diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java
+index 2e988d59404c52cd9c290b96d21f886573cda0fa..0e632f9eabd0d55a4eaacff54abaf637660528dd 100644
+--- a/src/main/java/net/minecraft/world/entity/Entity.java
++++ b/src/main/java/net/minecraft/world/entity/Entity.java
+@@ -235,6 +235,8 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource {
+     public com.destroystokyo.paper.loottable.PaperLootableInventoryData lootableData; // Paper
+     private CraftEntity bukkitEntity;
+ 
++    public @org.jetbrains.annotations.Nullable net.minecraft.server.level.ChunkMap.TrackedEntity tracker; // Paper
++    public @Nullable Throwable addedToWorldStack; // Paper - entity debug
+     public CraftEntity getBukkitEntity() {
+         if (this.bukkitEntity == null) {
+             this.bukkitEntity = CraftEntity.getEntity(this.level.getCraftServer(), this);
+diff --git a/src/main/java/net/minecraft/world/level/Level.java b/src/main/java/net/minecraft/world/level/Level.java
+index f4249ee3259a95b9f079a75c78ccf96a14b99b0d..9ed8117afa4eb1ff9e7403d3ab92a9e6cb0fab73 100644
+--- a/src/main/java/net/minecraft/world/level/Level.java
++++ b/src/main/java/net/minecraft/world/level/Level.java
+@@ -148,6 +148,7 @@ public abstract class Level implements LevelAccessor, AutoCloseable {
+     public boolean pvpMode;
+     public boolean keepSpawnInMemory = true;
+     public org.bukkit.generator.ChunkGenerator generator;
++    public static final boolean DEBUG_ENTITIES = Boolean.getBoolean("debug.entities"); // Paper
+ 
+     public boolean preventPoiUpdated = false; // CraftBukkit - SPIGOT-5710
+     public boolean captureBlockStates = false;
+diff --git a/src/main/java/net/minecraft/world/level/entity/EntityLookup.java b/src/main/java/net/minecraft/world/level/entity/EntityLookup.java
+index e6b9f812e521abd552e0c7dc0429d5a62f2bfc35..f4731d69946871768ecf16149a47d2ef1cb3e910 100644
+--- a/src/main/java/net/minecraft/world/level/entity/EntityLookup.java
++++ b/src/main/java/net/minecraft/world/level/entity/EntityLookup.java
+@@ -34,6 +34,26 @@ public class EntityLookup<T extends EntityAccess> {
+         UUID uUID = entity.getUUID();
+         if (this.byUuid.containsKey(uUID)) {
+             LOGGER.warn("Duplicate entity UUID {}: {}", uUID, entity);
++            // Paper start - extra debug info
++            if (entity instanceof net.minecraft.world.entity.Entity entityCast) {
++                if (net.minecraft.server.level.ServerLevel.DEBUG_ENTITIES) {
++                    entityCast.addedToWorldStack = net.minecraft.server.level.ServerLevel.getAddToWorldStackTrace(entityCast);
++                }
++
++                T old = this.byUuid.get(entity.getUUID());
++                if (old instanceof net.minecraft.world.entity.Entity oldCast && old != null && oldCast.getId() != entity.getId() && oldCast.valid) {
++                    LOGGER.error("Overwrote an existing entity " + oldCast + " with " + entity);
++                    if (net.minecraft.server.level.ServerLevel.DEBUG_ENTITIES) {
++                        if (oldCast.addedToWorldStack != null) {
++                            oldCast.addedToWorldStack.printStackTrace();
++                        } else {
++                            LOGGER.error("Oddly, the old entity was not added to the world in the normal way. Plugins?");
++                        }
++                        entityCast.addedToWorldStack.printStackTrace();
++                    }
++                }
++            }
++            // Paper end
+         } else {
+             this.byUuid.put(uUID, entity);
+             this.byId.put(entity.getId(), entity);