Spigot FernFlower has a slight regression compared to the standard FernFlower; it doesn't break the code, it's just a code/visual style issue.

The problem in question is:
To reference a variable in the same class, Spigot FernFlower uses ClassName.VARIABLE instead of just the variable directly.

Steps to reproduce:
Basically, run buildtools and get the BlockLantern class and look at the getConnectedDirection(IBlockData) method and decompile it with normal FernFlower and you will see the difference...