MinecraftForge/MinecraftForge — pull request #666 by SMEZ1234 (2013-07-11 07:43:12+00:00)
Title: Makes MapGenCaves check a list for exception biomes

At the moment mushroom island, beach and desert biomes are the only exception biomes.

This makes the exception biomes into a list, so that a mod can set one of its biomes to be an 'exception biome'. The same change should be made to MapGenRavine.