Stack overflow when executing permission command

[valeth]

I encountered a stack overflow while testing on a local server
when executing a command like /permission group players grant minecraft.help.command

Server container logs:

...
minecraft_1  | [15:50:20] [Gunpowder Database Thread/INFO]: [STDERR]: java.lang.StackOverflowError
minecraft_1  | [15:50:20] [Gunpowder Database Thread/INFO]: [STDERR]:   at java.base/java.lang.String.indexOf(Unknown Source)
minecraft_1  | [15:50:20] [Gunpowder Database Thread/INFO]: [STDERR]:   at kotlin.text.StringsKt__StringsKt.indexOf(Strings.kt:1105)
minecraft_1  | [15:50:20] [Gunpowder Database Thread/INFO]: [STDERR]:   at kotlin.text.StringsKt__StringsKt.split$StringsKt__StringsKt(Strings.kt:1346)
minecraft_1  | [15:50:20] [Gunpowder Database Thread/INFO]: [STDERR]:   at kotlin.text.StringsKt__StringsKt.split(Strings.kt:1328)
minecraft_1  | [15:50:20] [Gunpowder Database Thread/INFO]: [STDERR]:   at kotlin.text.StringsKt__StringsKt.split$default(Strings.kt:1326)
minecraft_1  | [15:50:20] [Gunpowder Database Thread/INFO]: [STDERR]:   at io.github.gunpowder.entities.PermissionTree.getOrCreate(PermissionTree.java:46)
minecraft_1  | [15:50:20] [Gunpowder Database Thread/INFO]: [STDERR]:   at io.github.gunpowder.entities.PermissionTree.getOrCreate(PermissionTree.java:47)
minecraft_1  | [15:50:20] [Gunpowder Database Thread/INFO]: [STDERR]:   at io.github.gunpowder.entities.PermissionTree.getOrCreate(PermissionTree.java:47)
minecraft_1  | [15:50:20] [Gunpowder Database Thread/INFO]: [STDERR]:   at io.github.gunpowder.entities.PermissionTree.getOrCreate(PermissionTree.java:47)
...
minecraft_1  | [15:51:28] [Server Watchdog/FATAL]: A single server tick took 60.00 seconds (should be max 0.05)
minecraft_1  | [15:51:28] [Server Watchdog/FATAL]: Considering it to be crashed, server will forcibly shutdown.

After that the server locks up and crashes shortly after, attempting to log in just results in a timeout.

crash-2021-07-14_16.02.27-server.txt

[Martmists-GH]

I think due to some wacky optimization the elements are joined before the first element is removed, will check this weekend.