Issue with breaking blocks in a chunk (Unloaded chunk at x, y, z)

[Fisher2911]

Basically, I'm trying to create an instance for a player in the PlayerLoginEvent, but it seems like when the player breaks a block, it throws an error in console and doesn't drop an item. This same code was working with regular Minestom.

Player login listener
CustomChunkGenerator
Block I'm trying to break that doesn't drop anything
createDefaultHandler method - this is where the error occurs
Version:

implementation("dev.hollowcube:minestom-ce:010fe985bb")

Error:

java.lang.NullPointerException: Unloaded chunk at -144,-64,112
	at net.minestom.server.instance.Instance.getBlock(Instance.java:596)
	at net.minestom.server.instance.block.Block$Getter.getBlock(Block.java:218)
	at net.minestom.server.instance.block.Block$Getter.getBlock(Block.java:226)
	at io.github.fisher2911.myserver.world.BlockHandlersKt$createDefaultHandler$3.onDestroy(BlockHandlers.kt:32)
	at net.minestom.server.instance.DynamicChunk.setBlock(DynamicChunk.java:111)
	at net.minestom.server.instance.Chunk.setBlock(Chunk.java:91)
	at net.minestom.server.instance.AnvilLoader.loadBlockEntities(AnvilLoader.java:300)
	at net.minestom.server.instance.AnvilLoader.loadMCA(AnvilLoader.java:129)
	at net.minestom.server.instance.AnvilLoader.loadChunk(AnvilLoader.java:87)
	at net.minestom.server.instance.InstanceContainer.lambda$retrieveChunk$6(InstanceContainer.java:294)
	at java.base/java.util.concurrent.CompletableFuture$AsyncRun.run(CompletableFuture.java:1804)
	at java.base/java.util.concurrent.CompletableFuture$AsyncRun.exec(CompletableFuture.java:1796)
	at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:373)
	at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1182)
	at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1655)
	at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1622)
	at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:165)

[Fisher2911]

It only seems to be happening when loading chunks from a file

[Fisher2911]

The issue seems to be that the chunk is cached after the chunk is generated

[Fisher2911]

If you want to reproduce, this causes it:

MinecraftServer.getBlockManager().registerHandler("minecraft:stone") {
    object : BlockHandler {
        override fun getNamespaceId(): NamespaceID {
            return NamespaceID.from("minecraft:stone")
        }
        override fun onDestroy(destroy: BlockHandler.Destroy) {
            println("destroyed stone")
            val position = destroy.blockPosition
            destroy.instance.getBlock(position)
        }
    }
}

instanceContainer.chunkLoader = AnvilLoader("worlds/${player.uuid}")
instanceContainer.setGenerator { unit: GenerationUnit -> unit.modifier().fillHeight(0, 40, Block.STONE)

private fun onPlayerLogout(
    globalEventHandler: GlobalEventHandler
) {
    globalEventHandler.addListener(
        PlayerDisconnectEvent::class.java
    ) { event: PlayerDisconnectEvent ->
        val player: Player = event.player
        player.instance.saveChunksToStorage()
    }
}

Steps:

1. Join the server
2. Leave
3. Join back