From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: MrHua269 <mrhua269@gmail.com>
Date: Sun, 25 May 2025 23:05:15 +0800
Subject: [PATCH] Fix chunk iteration self modification

We use the old-like logics which is in 1.21.4.
Might fixes: https://github.com/PaperMC/Folia/issues/363

diff --git a/net/minecraft/server/level/ServerChunkCache.java b/net/minecraft/server/level/ServerChunkCache.java
index f8322334fb6a0cea38c4d1981862ba673fd1b100..0e08512ce94435ca90a2344eefc761fa4fcdeb18 100644
--- a/net/minecraft/server/level/ServerChunkCache.java
+++ b/net/minecraft/server/level/ServerChunkCache.java
@@ -173,14 +173,26 @@ public class ServerChunkCache extends ChunkSource implements ca.spottedleaf.moon
         // 2. _removes_ are impossible at this stage in the tick
         final LevelChunk[] raw = entityTickingChunks.getRawDataUnchecked();
         final int size = entityTickingChunks.size(); foliaProfiler.addCounter(ca.spottedleaf.leafprofiler.LProfilerRegistry.RANDOM_CHUNK_TICK_COUNT, (long)size); // Folia - profiler
+        // Luminol start - Fix chunk iteration self modification - use copy of raw array
+        final LevelChunk[] rawCopy = new LevelChunk[size];
+        System.arraycopy(raw, 0, rawCopy, 0, size);
+        // Luminol end
 
-        java.util.Objects.checkFromToIndex(0, size, raw.length);
+        this.level.getServer().moonrise$executeMidTickTasks(); // Luminol - Fix chunk iteration self modification - try executing mid-tick tasks for once chunk system task parsing
+        java.util.Objects.checkFromToIndex(0, size, rawCopy.length); // Luminol - Fix chunk iteration self modification - use copy of raw array
         for (int i = 0; i < size; ++i) {
-            world.tickChunk(raw[i], randomTickSpeed);
+            // Luminol start - Fix chunk iteration self modification
+            final LevelChunk chunk = rawCopy[i];
+
+            if (!chunk.getFullStatus().isOrAfter(FullChunkStatus.ENTITY_TICKING)) {
+                continue; // skip chunks which are not entity ticking(probably downgraded from last iteration)
+            }
+            // Luminol end
+            world.tickChunk(chunk, randomTickSpeed); // Luminol - Fix chunk iteration self modification - use copy of raw array
 
             // call mid-tick tasks for chunk system
             if ((i & 7) == 0) {
-                //((ca.spottedleaf.moonrise.patches.chunk_system.server.ChunkSystemMinecraftServer)this.level.getServer()).moonrise$executeMidTickTasks(); // Folia - TODO restore this
+                ((ca.spottedleaf.moonrise.patches.chunk_system.server.ChunkSystemMinecraftServer)this.level.getServer()).moonrise$executeMidTickTasks(); // Folia - TODO restore this // Luminol - Fix chunk iteration self modification - restore mid tasks here
                 continue;
             }
         }