From 34ea199fb0da75890930f019d28dc78dc2b0e26a Mon Sep 17 00:00:00 2001
From: "Dylan K. Taylor" <dktapps@pmmp.io>
Date: Tue, 2 Nov 2021 14:30:23 +0000
Subject: [PATCH] World: fixed additional edge case - population promise
 rejected before task completion if this happened, the index would stay set in
 activeChunkPopulationTasks, eventually causing the generation queue to jam up
 completely and non-forced generation to come to a standstill.

---
 src/world/World.php | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/world/World.php b/src/world/World.php
index 3725da08e..cb4039b89 100644
--- a/src/world/World.php
+++ b/src/world/World.php
@@ -2918,7 +2918,11 @@ class World implements ChunkManager{
 			}
 		}
 
-		if(isset($this->chunkPopulationRequestMap[$index = World::chunkHash($x, $z)]) && isset($this->activeChunkPopulationTasks[$index])){
+		$index = World::chunkHash($x, $z);
+		if(!isset($this->chunkPopulationRequestMap[$index])){
+			$this->logger->debug("Discarding population result for chunk x=$x,z=$z - promise was already broken");
+			unset($this->activeChunkPopulationTasks[$index]);
+		}elseif(isset($this->activeChunkPopulationTasks[$index])){
 			if($dirtyChunks === 0){
 				$oldChunk = $this->loadChunk($x, $z);
 				$this->setChunk($x, $z, $chunk);