ConcurrentModificationException while unregistering plugin in onDisable #494
Description
CommandAPI version
9.2.0
Minecraft version
1.19.4
Running Paper git-Paper-524 (MC: 1.19.4) (Git: 9846d0d)
Are you shading the CommandAPI?
Yes
What I did
Using the below test plugin which shades/shadows CommandAPI, and a plugin which allows unloading individual plugins (such as PlugmanX or ServerUtils), start the server as normal, then unload our test plugin.
@Override
public void onLoad() {
CommandAPI.onLoad(
CommandAPIBukkitConfig(this)
.silentLogs(false)
.verboseOutput(true)
);
}
@Override
public void onEnable() {
CommandAPI.onEnable();
new CommandAPICommand("stuff")
// This is where the command would go if I could find a case where it reliably breaks.
.register();
}
@Override
public void onDisable() {
CommandAPI.unregister("stuff");
CommandAPI.onDisable();
}What actually happened
The command was unregistered, but doing it left the following stack trace in the server logs:
[22:54:00 INFO]: [CommandAPI] Unregistering command /stuff
[22:54:00 ERROR]: Caught previously unhandled exception :
[22:54:00 ERROR]: Paper Async Command Builder Thread Pool - 0
java.util.ConcurrentModificationException: null
at java.util.TreeMap$PrivateEntryIterator.nextEntry(Unknown Source) ~[?:?]
at java.util.TreeMap$ValueIterator.next(Unknown Source) ~[?:?]
at net.minecraft.commands.Commands.fillUsableCommands(Commands.java:475) ~[?:?]
at net.minecraft.commands.Commands.sendAsync(Commands.java:441) ~[?:?]
at net.minecraft.commands.Commands.lambda$sendCommands$5(Commands.java:414) ~[?:?]
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) ~[?:?]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) ~[?:?]
at java.lang.Thread.run(Unknown Source) ~[?:?]
Unfortunately, I've been unable to reliably reproduce it once I started. Maybe it's a race condition? That'd be fun!
What should have happened
Command /stuff should be unregistered without an exception.
Server logs and CommandAPI config
No response
Other
No response