GDLauncher does not install the -client.jar file correctly when upgrading forge version in an instance

[jmbjorndalen]

• [x] I searched the issue tracker for other issues covering my case
• [x] This is a Launcher issue. (Usually if you can reproduce it with a fresh instance)

Describe the bug Fresh instance with a forge version that has not been installed before, or upgrade existing instance to a new forge version. If the instance has a few mods installed, it will crash upon launch. The error message can vary. Sometimes it looks like the SLF4J issue that other issues have reported. I have also observed other error messages.

The problem seems to be that GDLauncher doesn't correctly set up the forge files in the internal datastore/libraries/net/minecraftforge/forge/ directories. It misses one file: forge-<mcversion>-<forgeversion>-client.jar.

To Reproduce

Steps to reproduce the behavior:

1. Install a new instance with a forge version that doesn't already work in an existing instance. Alternatively: upgrade an existing instance to a new forge version that is not already working in the launcher.
2. If it's a fresh instance, install a few mods (running forge without mods doesn't seem to trigger the bug).
3. Launch
4. A creeper blew this instance up!

To check for versions that are incomplete (on linux):
in gdlauncher_next/datastore: find . -iname forge\*.jar | grep -Ei 'universal|client' | sort

look for forge versions that have the universal.jar file, but not the client.jar file.

Expected behavior Instance should not crash on launch.

Possible solutions Workaround 1:

1. install the desired forge version somewhere else
2. copy the forge-<mcversion>-<forgeversion>-client.jar (ex: forge-1.19.2-43.1.65-client.jar) into GDLauncher's datastore/libraries/net/minecraftforge/forge/<mcversion>-<forgeversion>/ directory (should be next to the similarly named forge-<mcversion>-<forgeversion>-universal.jar file).
3. "upgrade" the forge version of the instance to the same version.

It should now work.

Workaround 2: Check GDLauncher's datastore (as seen above) and look for a forge version that has a xxxx-client.jar file. Change forge version of the instance to the closest one to the version you want.

Operating System:

• Linux (Ubuntu 22.04)
• Launcher Version: 1.1.29
• Java Version: 1.17
• Minecraft Version: Mostly tested with 1.19.2, but seems to be happening to 1.18 instances as well.
• Mod Loader: Forge

[Lilith207]

I would like to add with this issue with a reference to https://github.com/Creators-of-Create/Create/issues/5278 (contains logs) as it seemed like it was an issue with create, as if that was added it would crash (forge 40.2.10, i tried multible instances). but when i made an instance on curseforge and added create it did not do the same thing. it just worked. meaning that there is a good chance that curseforge is handeling the installation wrong?