Option to have default CustomSpawners in custom worlds (#7493)

patches/server/0875-Option-to-have-default-CustomSpawners-in-custom-worl.patch

@@ -0,0 +1,46 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Jake Potrebic <jake.m.potrebic@gmail.com>
+Date: Sat, 19 Feb 2022 20:15:41 -0800
+Subject: [PATCH] Option to have default CustomSpawners in custom worlds
+
+By default, only LevelStem's that specifically match the ResourceKey for
+OVERWORLD will have the 5 (currently) impls of CustomSpawner (for
+phantoms, wandering traders, etc.). This adds an option to instead of
+just looking at the LevelStem key, look at the DimensionType key which
+is one level below that. Defaults to off to keep vanilla behavior.
+
+diff --git a/src/main/java/com/destroystokyo/paper/PaperConfig.java b/src/main/java/com/destroystokyo/paper/PaperConfig.java
+index 153f07bac06093b43a1f5b0f8e1a46ffbe6407e5..a7ebf6d9f79ce50a90c3c903563e00a10607f9f2 100644
+--- a/src/main/java/com/destroystokyo/paper/PaperConfig.java
++++ b/src/main/java/com/destroystokyo/paper/PaperConfig.java
+@@ -679,4 +679,9 @@ public class PaperConfig {
+         }
+         globalMaxConcurrentChunkLoads = getDouble("settings.chunk-loading.global-max-concurrent-loads", 500.0);
+     }
++
++    public static boolean useDimensionTypeForCustomSpawners;
++    private static void useDimensionTypeForCustomSpawners() {
++        useDimensionTypeForCustomSpawners = getBoolean("settings.use-dimension-type-for-custom-spawners", false);
++    }
+ }
+diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
+index 053dbe5eef6574cfe98ab7499181bdd83a81f2e1..6d1d83bc17403346cc9d3143666b927ef55fb9df 100644
+--- a/src/main/java/net/minecraft/server/MinecraftServer.java
++++ b/src/main/java/net/minecraft/server/MinecraftServer.java
+@@ -689,7 +689,15 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
+                 this.commandStorage = new CommandStorage(worldpersistentdata);
+             } else {
+                 ChunkProgressListener worldloadlistener = this.progressListenerFactory.create(11);
+-                world = new ServerLevel(this, this.executor, worldSession, iworlddataserver, worldKey, dimensionmanager, worldloadlistener, chunkgenerator, flag, j, ImmutableList.of(), true, org.bukkit.World.Environment.getEnvironment(dimension), gen, biomeProvider);
++                // Paper start - option to use the dimension_type to check if spawners should be added. I imagine mojang will add some datapack-y way of managing this in the future.
++                final List<CustomSpawner> spawners;
++                if (com.destroystokyo.paper.PaperConfig.useDimensionTypeForCustomSpawners && this.registryHolder.registryOrThrow(Registry.DIMENSION_TYPE_REGISTRY).getResourceKey(dimensionmanager).orElseThrow() == DimensionType.OVERWORLD_LOCATION) {
++                    spawners = list;
++                } else {
++                    spawners = Collections.emptyList();
++                }
++                world = new ServerLevel(this, this.executor, worldSession, iworlddataserver, worldKey, dimensionmanager, worldloadlistener, chunkgenerator, flag, j, spawners, true, org.bukkit.World.Environment.getEnvironment(dimension), gen, biomeProvider);
++                // Paper end
+             }
+ 
+             worlddata.setModdedInfo(this.getServerModName(), this.getModdedStatus().shouldReportAsModified());