Crash `onLoadConfig`: `UnsupportedOperatationException`

[C0D3-M4513R]

Not me that found it, but a person on the Magma discord.

Issue ticket:

• Full Magma version: Magma-1.18.2-40.2.1-7b451705-server
• Java version: 17
• A detailed description of your issue: server didnt start properly
• Logs (server-instance/logs/latest.log) - https://mclo.gs/: crash report: https://mclo.gs/A5BSBhN | server log: https://mclo.gs/ATOONow
• Debug (server-instance/logs/debug.log): https://mclo.gs/7NLEqoI
• Mod list: https://mclo.gs/V2SQnde
• Plugin list: none
• Datapack list: DawnCraft - An Adventure RPG Modpack
• local host or hosting service: hosting service pukawka.pl
• Operating system: Linux
• Start-up script/flags: none

My response: Mod issue. This line: https://github.com/Sindarin27/farsighted-mobs-forge/blob/efcb7043f4faad59f4902bbd1f27444dadf179fa/src/main/java/com/sindarin/farsightedmobs/Config.java#L52 Puts a list into com.sindarin.farsightedmobs.Config$Server.mobAttributeMap, that cannot be changed. (https://docs.oracle.com/javase/8/docs/api/java/util/Collections.html#singletonList-T-) This line however is not correct: https://github.com/Sindarin27/farsighted-mobs-forge/blob/efcb7043f4faad59f4902bbd1f27444dadf179fa/src/main/java/com/sindarin/farsightedmobs/Config.java#L48 because it tries to change the list, that cannot be changed.

[Sindarin27]

Sorry for the late reply. I see the problem indeed; I naively assumed that Collections.singletonList would simply create a "normal" list containing the one element, but as you point out, it actually creates an immutable list. Since the mod currently only includes one attribute, this was not a problem. Seems like a simple enough fix, though.

[C0D3-M4513R]

I did a binary patch for that someone, that reported this btw. The change was actually simple.

(and yes I am accustomed to editing jvm bytecode by now, because many projects for 1.12.2 simply don't compile anymore... Thanks gradle for being so stable)