PaperMC/paper-server/patches/sources/net/minecraft/server/level/WorldGenRegion.java.patch

--- a/net/minecraft/server/level/WorldGenRegion.java
+++ b/net/minecraft/server/level/WorldGenRegion.java
@@ -169,7 +169,27 @@
         return k < this.generatingStep.directDependencies().size();
     }
 
+    // Paper start - if loaded util
+    @Nullable
     @Override
+    public ChunkAccess getChunkIfLoadedImmediately(int x, int z) {
+        return this.getChunk(x, z, ChunkStatus.FULL, false);
+    }
+
+    @Override
+    public final BlockState getBlockStateIfLoaded(BlockPos blockposition) {
+        ChunkAccess chunk = this.getChunkIfLoadedImmediately(blockposition.getX() >> 4, blockposition.getZ() >> 4);
+        return chunk == null ? null : chunk.getBlockState(blockposition);
+    }
+
+    @Override
+    public final FluidState getFluidIfLoaded(BlockPos blockposition) {
+        ChunkAccess chunk = this.getChunkIfLoadedImmediately(blockposition.getX() >> 4, blockposition.getZ() >> 4);
+        return chunk == null ? null : chunk.getFluidState(blockposition);
+    }
+    // Paper end
+
+    @Override
     public BlockState getBlockState(BlockPos pos) {
         return this.getChunk(SectionPos.blockToSectionCoord(pos.getX()), SectionPos.blockToSectionCoord(pos.getZ())).getBlockState(pos);
     }
@@ -217,7 +237,7 @@
         if (iblockdata.isAir()) {
             return false;
         } else {
-            if (drop) {
+            if (false) { // CraftBukkit - SPIGOT-6833: Do not drop during world generation
                 BlockEntity tileentity = iblockdata.hasBlockEntity() ? this.getBlockEntity(pos) : null;
 
                 Block.dropResources(iblockdata, this.level, pos, tileentity, breakingEntity, ItemStack.EMPTY);
@@ -336,6 +356,13 @@
 
     @Override
     public boolean addFreshEntity(Entity entity) {
+        // CraftBukkit start
+        return this.addFreshEntity(entity, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.DEFAULT);
+    }
+
+    @Override
+    public boolean addFreshEntity(Entity entity, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason reason) {
+        // CraftBukkit end
         int i = SectionPos.blockToSectionCoord(entity.getBlockX());
         int j = SectionPos.blockToSectionCoord(entity.getBlockZ());