What happened was i went onto the new snapshot, after converting some texture packs into resource packs, and decided to use one. But when i clicked it, nothing happened, so i went back onto the title screen and tried doing it, still nothing. So all of a sudden it crashed
So do this to get it:
1) Convert some texture packs; for example, disco's ocd texture pack and put it in the resource packs
2)Launch minecraft and open up the options, resource packs, and click on one
3)nothing will happen, so try clicking lots of times, and it will crash