Minecraftforge: [1.13.2] FMLClientSetupEvent and/or InterModProcessEvent sometimes not received for multiple mods

[thexaero]

I'm adding listeners for _FMLClientSetupEvent_ and _InterModProcessEvent_ in the main mod class constructor, the same way it's done in the example mod. Most of the time (always?), when there's only 1 mod to load, everything works as it should. But, when there are 2 (or more?) mods, it becomes very difficult to get all of the mods to actually load properly. Multiple restarts of the game eventually help.
These 2 messages are always logged for all of the mods:
_Fired event for modid : FMLClientSetupEvent
Fired event for modid : InterModProcessEvent_
But calling LOGGER.info("hello") on these events shows that sometimes some of the listeners are ignored. This is probably also true for the other loading events.

[williewillus]

likely race conditions in the bus?

[thexaero]

It definitely looks like it.

[RobertSkalko]

I seem to get this too. (1.13.2) I made a simple test mod to test commands and sometimes they register, other times not. The only other mods i added was jei, curios, curioofundying

[ichttt]

This is most likely because the main thread does not wait for the BackgroundScanHandler to complete, as BackgroundScanHandler.java#getScannedFiles is never called.
So not every mod jar may have been scanned by the time forge inits all mods.
EDIT: I just found that there is another place (ModFile#getScanResult) where forge waits on the scanning thread, so that doesn't appear to be the problem.

[cpw]

any way to reproduce this?

[cpw]

OK. A question: are you on a really old build of Forge? There was a problem where this might happen, which was fixed some weeks ago. Please reproduce on a contemporary forge build.

[thexaero]

I'm pretty sure the build was the latest one at the time of reporting this.
I've now tried reproducing it on a newer one.
25.0.204 doesn't start properly for me, even without any mods. Log:

`[12May2019 21:32:20.442] [modloading-worker-1/ERROR] [net.minecraftforge.fml.javafmlmod.FMLModContainer/LOADING]: Failed to create mod instance. ModID: forge, class net.minecraftforge.common.ForgeMod
java.lang.ExceptionInInitializerError: null
at net.minecraftforge.common.ForgeMod.(ForgeMod.java:89) ~[?:?]
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_201]
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) ~[?:1.8.0_201]
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) ~[?:1.8.0_201]
at java.lang.reflect.Constructor.newInstance(Unknown Source) ~[?:1.8.0_201]
at java.lang.Class.newInstance(Unknown Source) ~[?:1.8.0_201]
at net.minecraftforge.fml.javafmlmod.FMLModContainer.constructMod(FMLModContainer.java:130) ~[?:?]
at java.util.function.Consumer.lambda$andThen$0(Unknown Source) ~[?:1.8.0_201]
at java.util.function.Consumer.lambda$andThen$0(Unknown Source) ~[?:1.8.0_201]
at net.minecraftforge.fml.ModContainer.transitionState(ModContainer.java:111) ~[?:?]
at net.minecraftforge.fml.ModList.lambda$null$9(ModList.java:120) ~[?:?]
at java.util.stream.ForEachOps$ForEachOp$OfRef.accept(Unknown Source) ~[?:1.8.0_201]
at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(Unknown Source) ~[?:1.8.0_201]
at java.util.stream.AbstractPipeline.copyInto(Unknown Source) ~[?:1.8.0_201]
at java.util.stream.ForEachOps$ForEachTask.compute(Unknown Source) ~[?:1.8.0_201]
at java.util.concurrent.CountedCompleter.exec(Unknown Source) ~[?:1.8.0_201]
at java.util.concurrent.ForkJoinTask.doExec(Unknown Source) ~[?:1.8.0_201]
at java.util.concurrent.ForkJoinTask.doInvoke(Unknown Source) ~[?:1.8.0_201]
at java.util.concurrent.ForkJoinTask.invoke(Unknown Source) ~[?:1.8.0_201]
at java.util.stream.ForEachOps$ForEachOp.evaluateParallel(Unknown Source) ~[?:1.8.0_201]
at java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateParallel(Unknown Source) ~[?:1.8.0_201]
at java.util.stream.AbstractPipeline.evaluate(Unknown Source) ~[?:1.8.0_201]
at java.util.stream.ReferencePipeline.forEach(Unknown Source) ~[?:1.8.0_201]
at java.util.stream.ReferencePipeline$Head.forEach(Unknown Source) ~[?:1.8.0_201]
at net.minecraftforge.fml.ModList.lambda$dispatchParallelEvent$10(ModList.java:120) ~[?:?]
at java.util.concurrent.ForkJoinTask$AdaptedRunnableAction.exec(Unknown Source) [?:1.8.0_201]
at java.util.concurrent.ForkJoinTask.doExec(Unknown Source) [?:1.8.0_201]
at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(Unknown Source) [?:1.8.0_201]
at java.util.concurrent.ForkJoinPool.runWorker(Unknown Source) [?:1.8.0_201]
at java.util.concurrent.ForkJoinWorkerThread.run(Unknown Source) [?:1.8.0_201]
Caused by: java.lang.NullPointerException
at net.minecraftforge.fml.loading.JarVersionLookupHandler.getImplementationVersion(JarVersionLookupHandler.java:42) ~[forge-1.13.2-25.0.203.jar:25.0]
at net.minecraftforge.versions.forge.ForgeVersion.(ForgeVersion.java:44) ~[?:?]
... 30 more
25.0.198 is the latest version that successfully loads for me. The newer ones fail for different reasons.
Aaaand, I reproduced the issue on first try on 25.0.198. I'm testing it with the actual Minecraft launcher, by the way. The issue happens to me in dev environment too though.
Also, a lot of people who have reported this to me said that the issue had started after updating one of the mods to a newer version. Might just be a coincidence though because I know it happened with the older mod versions too.

[darty11]

I can confirm this as well. It seems most common in the main game, less common in a dev environment, and almost non-existent in the debug environment, which made it very difficult for me to pin down what was causing my mods not to work.

[cpw]

Pick up the new eventbus and it should work. We'll probably push a forge with it shortly.