Duplication issue

[ItsHarry]

Apparently, if you log off while you're in combat, and then very quickly log back in, for some reason the spawned NPC is not removed, so the player can see their own NPC.

When you then kill the NPC, you have duplicated the items.

Any chance this could be fixed?

[Techcable]

What version are you on?

[ItsHarry]

It was the one you sent me 21 days ago: http://ci.techcable.net/job/Combat%20Tag/34/

Link doesn't work anymore, but you'll understand what it means =)

[ItsHarry]

When do you think you'll have this fixed? This is a big problem on my server as players are abusing it to duplicate items.

[Techcable]

Do you have any idea how your players manage to log in and out fast enough?
I'm not sure if i could click fast enough.

[ItsHarry]

Sorry, I was told that was the way to do it. I will find out the exact steps to reproduce this and report back.

Apologies again

[ItsHarry]

Hmm, while trying to test this, no NPC was spawned each time my guinea pig pvplogged. This stack trace was printed:

[08:59:34] [Server thread/ERROR]: Could not pass event PlayerQuitEvent to CombatTag v6.4.1-SNAPSHOT
org.bukkit.event.EventException
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:302) ~[craftbukkit.jar:git-PaperSpigot-1.7.9-R0.2-266-g6a98d6f]
    at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[craftbukkit.jar:git-PaperSpigot-1.7.9-R0.2-266-g6a98d6f]
    at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:509) [craftbukkit.jar:git-PaperSpigot-1.7.9-R0.2-266-g6a98d6f]
    at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:494) [craftbukkit.jar:git-PaperSpigot-1.7.9-R0.2-266-g6a98d6f]
    at net.minecraft.server.v1_7_R4.PlayerList.disconnect(PlayerList.java:367) [craftbukkit.jar:git-PaperSpigot-1.7.9-R0.2-266-g6a98d6f]
    at net.minecraft.server.v1_7_R4.PlayerConnection.a(PlayerConnection.java:739) [craftbukkit.jar:git-PaperSpigot-1.7.9-R0.2-266-g6a98d6f]
    at net.minecraft.server.v1_7_R4.ServerConnection.c(ServerConnection.java:77) [craftbukkit.jar:git-PaperSpigot-1.7.9-R0.2-266-g6a98d6f]
    at net.minecraft.server.v1_7_R4.MinecraftServer.v(MinecraftServer.java:789) [craftbukkit.jar:git-PaperSpigot-1.7.9-R0.2-266-g6a98d6f]
    at net.minecraft.server.v1_7_R4.DedicatedServer.v(DedicatedServer.java:307) [craftbukkit.jar:git-PaperSpigot-1.7.9-R0.2-266-g6a98d6f]
    at net.minecraft.server.v1_7_R4.MinecraftServer.u(MinecraftServer.java:638) [craftbukkit.jar:git-PaperSpigot-1.7.9-R0.2-266-g6a98d6f]
    at net.minecraft.server.v1_7_R4.MinecraftServer.run(MinecraftServer.java:544) [craftbukkit.jar:git-PaperSpigot-1.7.9-R0.2-266-g6a98d6f]
    at net.minecraft.server.v1_7_R4.ThreadServerApplication.run(SourceFile:628) [craftbukkit.jar:git-PaperSpigot-1.7.9-R0.2-266-g6a98d6f]
Caused by: java.lang.IllegalArgumentException: NPC with UUID da083fd9-9188-4737-a654-1f1c7aa61c9c is already created
    at com.trc202.CombatTag.libs.npclib.nms.NMSRegistry.createNPC(NMSRegistry.java:50) ~[?:?]
    at com.trc202.CombatTag.NPCManager.spawnHumanNPC(NPCManager.java:39) ~[?:?]
    at com.trc202.CombatTag.CombatTag.spawnNpc(CombatTag.java:173) ~[?:?]
    at com.trc202.CombatTagListeners.NoPvpPlayerListener.onPlayerQuit(NoPvpPlayerListener.java:81) ~[?:?]
    at sun.reflect.GeneratedMethodAccessor276.invoke(Unknown Source) ~[?:?]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_45]
    at java.lang.reflect.Method.invoke(Method.java:497) ~[?:1.8.0_45]
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:298) ~[craftbukkit.jar:git-PaperSpigot-1.7.9-R0.2-266-g6a98d6f]
    ... 11 more

Could be related? Not sure though.

[Techcable]

I really have no idea how this could happen. Bukkit events are guaranteed to be executed synchronously. By any chance are you using RedXIII's async entity patch?

[ItsHarry]

Nope, I do not use it.

You know, if it is too much of a hassle, by all means just leave it. I have since switched to my own plugin anyway which just instakills the players, as I find NPCs to be unreliable.

[Techcable]

I'm working on a rewrite right now. I'm pretty busy updating cauldron to 1.8 so it may take a while to fix this issue 😢

[Techcable]

Try build 18 of Combat Tag 7.0.0 beta