Merge pull request #814 from pylonmc/human/scope-error-fix

Scope Cancel Fix

Author: LordIdra

rebar/src/main/kotlin/io/github/pylonmc/rebar/async/ChunkScope.kt

@@ -4,6 +4,7 @@ import com.google.common.collect.HashMultimap
 import io.github.pylonmc.rebar.util.position.ChunkPosition
 import io.github.pylonmc.rebar.util.position.position
 import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Job
 import kotlinx.coroutines.cancel
 import org.bukkit.event.EventHandler
 import org.bukkit.event.EventPriority
@@ -26,7 +27,11 @@ class ChunkScope(override val coroutineContext: CoroutineContext, chunk: ChunkPo
 
         @EventHandler(priority = EventPriority.MONITOR)
         private fun onChunkUnload(event: ChunkUnloadEvent) {
-            chunkScopes.removeAll(event.chunk.position).forEach { it.cancel() }
+            chunkScopes.removeAll(event.chunk.position).forEach {
+                if (it.coroutineContext[Job] != null) {
+                    it.cancel()
+                }
+            }
         }
     }
 }

rebar/src/main/kotlin/io/github/pylonmc/rebar/async/PlayerScope.kt

@@ -2,7 +2,10 @@ package io.github.pylonmc.rebar.async
 
 import com.google.common.collect.HashMultimap
 import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Job
 import kotlinx.coroutines.cancel
+import kotlinx.coroutines.currentCoroutineContext
+import kotlinx.coroutines.job
 import org.bukkit.Bukkit
 import org.bukkit.entity.Player
 import org.bukkit.event.EventHandler
@@ -29,7 +32,11 @@ class PlayerScope(override val coroutineContext: CoroutineContext, playerId: UUI
 
         @EventHandler(priority = EventPriority.MONITOR)
         private fun onPlayerQuit(event: PlayerQuitEvent) {
-            playerScopes.removeAll(event.player.uniqueId).forEach { it.cancel() }
+            playerScopes.removeAll(event.player.uniqueId).forEach {
+                if (it.coroutineContext[Job] != null) {
+                    it.cancel()
+                }
+            }
         }
     }
 }