I'm trying to setup a local Forge workspace to work on an issue I found recently (https://github.com/MinecraftForge/MinecraftForge/issues/9426)
So I've forked the Forge repo, followed all the steps described in the documentation (https://docs.minecraftforge.net/en/latest/forgedev/) and run the forge_client task. However when I do this I get this error
 

Exception in thread "main" java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
    at MC-BOOTSTRAP/[email protected]/cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:32)
    ...
Caused by: java.lang.ClassNotFoundException: net.minecraftforge.logging.CrashReportExtender

Am I missing some step? If I run the "clean_client" task it opens up the client just fine (but can't debug forge since it appears to not be loaded).

I've also noticed that there are some small test mods inside the test folder, which would be perfect to run and debug for my use case, but I can't find any documentation about how to debug these mods, so how can I do this?

2 hours ago, JimiIT92 said:

Am I missing some step? If I run the "clean_client" task it opens up the client just fine (but can't debug forge since it appears to not be loaded).

It may just be a bad setup, so I would invalidate cache, reload the gradle project, then run setup and generate the runs again.

2 hours ago, JimiIT92 said:

I've also noticed that there are some small test mods inside the test folder, which would be perfect to run and debug for my use case, but I can't find any documentation about how to debug these mods, so how can I do this?

When choosing your runs, use 'forge forge test client/server/data' instead of 'forge forge' or 'forge clean'

I did these steps:

From IntellJ > File > Invalidate caches. Checked all checkboxes and restart the IDE

After I opened up the Forge project and let the indexing going on. When the indexing stops I ran the setup task and then the genIntellijRuns task.

Finally I ran the forge_test_client task, but still got the issue Don't really know what could it be, I even tried deleting the whole .gradle folder from my pc, just in case something was left from the invalidate cache process, but still no luck