get_dir() doesn't validate that the arguments given to it are actually correct, and in the case that they aren't, it simply always returns SOUTH (2).
Code Snippet (if applicable) to Reproduce Problem:
mob/verb/test()
var/a = pick(world,new /savefile,123,"a")
src << get_dir(a,src)
Expected Results:
A runtime error.
Actual Results:
Returns 2.