Bug in version 4.0.x with custom items from WeaponMechanics ?

[Jeppa]

Custom Items:
WeaponMechanics items inside of classes.yml (on a 1.21.4 server with WeaponMechanics 4.0.x) throw an error during server start if added to "classes..items" !
But a '/ba reload' done later will NOT throw that error!

[Redned235]

Can you please include the error log? Not much I can do without it.

[Jeppa]

Please note that it is the new WeaponMechanics recode version... (ver 4.x)
Maybe there is an incompatibility now...

OK, here is the log:

[17:05:33] [Server thread/ERROR]: [BattleArena] 
------------------------------------------------------------
An internal error occurred while parsing a file.

Error: An internal error occurred while parsing the file: Failed to post-process instance of class org.battleplugins.arena.module.classes.ArenaClass

Please see the following file causing the reported error: C:\Paper_Test_1-21-4\plugins\BattleArena\classes.yml

Additionally, the following documentation may be relevant to resolving the error: https://docs.battleplugins.org/books/user-guide/page/classes
It is likely that this error is due to a problem or misconfiguration in the plugin. Please report the following stacktrace to the BattlePlugins developers!
Stacktrace:
org.battleplugins.arena.config.ParseException: Failed to post-process instance of class org.battleplugins.arena.module.classes.ArenaClass
Caused by: java.lang.NullPointerException: Cannot invoke "me.deecaad.core.file.Configuration.getObject(String, java.lang.Class)" because the return value of "me.deecaad.weaponmechanics.WeaponMechanics.getConfigurations()" is null
	at WeaponMechanics-4.0.4.jar//me.deecaad.weaponmechanics.weapon.info.InfoHandler.generateWeapon(InfoHandler.java:171)
	at WeaponMechanics-4.0.4.jar//me.deecaad.weaponmechanics.WeaponMechanicsAPI.generateWeapon(WeaponMechanicsAPI.java:370)
	at org.battleplugins.arena.module.items.weaponmechanics.WeaponMechanicsFeature.createItem(WeaponMechanicsFeature.java:17)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.feature.items.ItemsFeature.createItem(ItemsFeature.java:39)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.feature.items.Items.createItem(Items.java:31)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.config.ItemStackParser.deserializeSingular(ItemStackParser.java:71)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.config.ItemStackParser.parse(ItemStackParser.java:35)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.config.ItemStackParser.parse(ItemStackParser.java:28)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.config.ArenaConfigParser.parseList(ArenaConfigParser.java:428)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.config.ArenaConfigParser.populateType(ArenaConfigParser.java:217)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.config.ArenaConfigParser.populateFields(ArenaConfigParser.java:134)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.config.ArenaConfigParser.newInstance(ArenaConfigParser.java:57)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.config.ArenaConfigParser.newInstance(ArenaConfigParser.java:45)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.config.ArenaConfigParser.parseMap(ArenaConfigParser.java:509)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.config.ArenaConfigParser.populateType(ArenaConfigParser.java:237)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.config.ArenaConfigParser.populateFields(ArenaConfigParser.java:134)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.config.ArenaConfigParser.newInstance(ArenaConfigParser.java:57)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.config.ArenaConfigParser.newInstance(ArenaConfigParser.java:45)
	at org.battleplugins.arena.module.classes.Classes.onLoad(Classes.java:71)
	at org.battleplugins.arena.module.classes.Classes.onPostInitialize(Classes.java:40)
	at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:80)
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:70)
	at io.papermc.paper.plugin.manager.PaperEventManager.callEvent(PaperEventManager.java:54)
	at io.papermc.paper.plugin.manager.PaperPluginManagerImpl.callEvent(PaperPluginManagerImpl.java:131)
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:628)
	at org.bukkit.event.Event.callEvent(Event.java:45)
	at BattleArena_4.0.3_Snap84.jar//org.battleplugins.arena.BattleArenaListener.onServerLoad(BattleArenaListener.java:26)
	at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:80)
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:70)
	at io.papermc.paper.plugin.manager.PaperEventManager.callEvent(PaperEventManager.java:54)
	at io.papermc.paper.plugin.manager.PaperPluginManagerImpl.callEvent(PaperPluginManagerImpl.java:131)
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:628)
	at net.minecraft.server.MinecraftServer.loadWorld0(MinecraftServer.java:750)
	at net.minecraft.server.MinecraftServer.loadLevel(MinecraftServer.java:488)
	at net.minecraft.server.dedicated.DedicatedServer.initServer(DedicatedServer.java:322)
	at net.minecraft.server.MinecraftServer.runServer(MinecraftServer.java:1163)
	at net.minecraft.server.MinecraftServer.lambda$spin$2(MinecraftServer.java:310)
	at java.base/java.lang.Thread.run(Unknown Source)