Hi. I just remembered a certain gun mod, although I don't remember much details about it. All I remember is that it had a firework launcher gun, and an arrow shooting gun. I know it's not much detail, but any help is appreciated.
I'm not sure if this is what you mean, but maybe it is Jack-o'-Launcher?
No, it isn't that mod. The one I'm talking about added many more guns, not just one that shoots pumpkins. I'm sure it didn't have a pumpkin launcher gun, too.
EDIT: I just found the mod, it was called QuiverBow. It hasn't been updated to 1.12.2, though, which is a shame. I really love it.