Fix creation of invalid block entity during world generation

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

@@ -1,12 +1,14 @@
 --- a/net/minecraft/server/level/WorldGenRegion.java
 +++ b/net/minecraft/server/level/WorldGenRegion.java
-@@ -169,7 +169,27 @@
+@@ -167,7 +167,27 @@
-         return k < this.generatingStep.directDependencies().size();
+         int k = this.center.getPos().getChessboardDistance(chunkX, chunkZ);
-     }
  
+         return k < this.generatingStep.directDependencies().size();
++    }
++
 +    // Paper start - if loaded util
 +    @Nullable
-     @Override
++    @Override
 +    public ChunkAccess getChunkIfLoadedImmediately(int x, int z) {
 +        return this.getChunk(x, z, ChunkStatus.FULL, false);
 +    }
@@ -21,13 +23,11 @@
 +    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);
      }
++    // Paper end
+ 
+     @Override
+     public BlockState getBlockState(BlockPos pos) {
 @@ -217,7 +237,8 @@
          if (iblockdata.isAir()) {
              return false;
@@ -62,7 +62,34 @@
              return false;
          }
      }
-@@ -336,6 +366,13 @@
+@@ -294,7 +324,7 @@
+             return false;
+         } else {
+             ChunkAccess ichunkaccess = this.getChunk(pos);
+-            BlockState iblockdata1 = ichunkaccess.setBlockState(pos, state, false);
++            BlockState iblockdata1 = ichunkaccess.setBlockState(pos, state, false); final BlockState previousBlockState = iblockdata1; // Paper - Clear block entity before setting up a DUMMY block entity - obfhelper
+ 
+             if (iblockdata1 != null) {
+                 this.level.onBlockStateChange(pos, iblockdata1, state);
+@@ -310,6 +340,17 @@
+                         ichunkaccess.removeBlockEntity(pos);
+                     }
+                 } else {
++                    // Paper start - Clear block entity before setting up a DUMMY block entity
++                    // The concept of removing a block entity when the block itself changes is generally lifted
++                    // from LevelChunk#setBlockState.
++                    // It is however to note that this may only run if the block actually changes.
++                    // Otherwise a chest block entity generated by a structure template that is later "updated" to
++                    // be waterlogged would remove its existing block entity (see PaperMC/Paper#10750)
++                    // This logic is *also* found in LevelChunk#setBlockState.
++                    if (previousBlockState != null && !java.util.Objects.equals(previousBlockState.getBlock(), state.getBlock())) {
++                        ichunkaccess.removeBlockEntity(pos);
++                    }
++                    // Paper end - Clear block entity before setting up a DUMMY block entity
+                     CompoundTag nbttagcompound = new CompoundTag();
+ 
+                     nbttagcompound.putInt("x", pos.getX());
+@@ -336,6 +377,13 @@
  
      @Override
      public boolean addFreshEntity(Entity entity) {

paper-server/patches/sources/net/minecraft/world/level/chunk/LevelChunk.java.patch

@@ -110,15 +110,15 @@
      public FluidState getFluidState(int x, int y, int z) {
 -        try {
 -            int l = this.getSectionIndex(y);
--
--            if (l >= 0 && l < this.sections.length) {
--                LevelChunkSection chunksection = this.sections[l];
 +        // Paper start - Perf: Optimise Chunk#getFluid
 +        // try {  // Remove try catch
 +        int index = this.getSectionIndex(y);
 +            if (index >= 0 && index < this.sections.length) {
 +                LevelChunkSection chunksection = this.sections[index];
  
+-            if (l >= 0 && l < this.sections.length) {
+-                LevelChunkSection chunksection = this.sections[l];
+-
                  if (!chunksection.hasOnlyAir()) {
 -                    return chunksection.getFluidState(x & 15, y & 15, z & 15);
 +                    return chunksection.states.get((y & 15) << 8 | (z & 15) << 4 | x & 15).getFluidState();
@@ -288,7 +288,7 @@
              if (tileentity != null) {
                  Level world = this.level;
  
-@@ -549,9 +626,68 @@
+@@ -549,10 +626,69 @@
          if (this.postLoad != null) {
              this.postLoad.run(this);
              this.postLoad = null;
@@ -335,7 +335,7 @@
 +            }
          }
 +    }
-+
+ 
 +    public void unloadCallback() {
 +        org.bukkit.Server server = this.level.getCraftServer();
 +        org.bukkit.Chunk bukkitChunk = new org.bukkit.craftbukkit.CraftChunk(this);
@@ -347,16 +347,17 @@
 +        // Paper start
 +        this.loadedTicketLevel = false;
 +        // Paper end
-+    }
+     }
  
 +    @Override
 +    public boolean isUnsaved() {
 +        return super.isUnsaved() && !this.mustNotSave;
-     }
++    }
 +    // CraftBukkit end
- 
++
      public boolean isEmpty() {
          return false;
+     }
 @@ -750,7 +886,7 @@
  
      private <T extends BlockEntity> void updateBlockEntityTicker(T blockEntity) {
@@ -375,7 +376,22 @@
              this.ticker = blockentityticker;
          }
  
-@@ -867,11 +1003,13 @@
+@@ -860,18 +996,25 @@
+                         if (this.blockEntity.getType().isValid(iblockdata)) {
+                             this.ticker.tick(LevelChunk.this.level, this.blockEntity.getBlockPos(), iblockdata, this.blockEntity);
+                             this.loggedInvalidBlockState = false;
+-                        } else if (!this.loggedInvalidBlockState) {
+-                            this.loggedInvalidBlockState = true;
+-                            LevelChunk.LOGGER.warn("Block entity {} @ {} state {} invalid for ticking:", new Object[]{LogUtils.defer(this::getType), LogUtils.defer(this::getPos), iblockdata});
++                        // Paper start - Remove the Block Entity if it's invalid
++                        } else {
++                            LevelChunk.this.removeBlockEntity(this.getPos());
++                            if (!this.loggedInvalidBlockState) {
++                                this.loggedInvalidBlockState = true;
++                                LevelChunk.LOGGER.warn("Block entity {} @ {} state {} invalid for ticking:", new Object[]{LogUtils.defer(this::getType), LogUtils.defer(this::getPos), iblockdata});
++                            }
++                            // Paper end - Remove the Block Entity if it's invalid
+                         }
  
                          gameprofilerfiller.pop();
                      } catch (Throwable throwable) {