JuliaLang/julia — pull request #4924 by staticfloat (2013-11-25 19:40:54+00:00)
Title: Disallow the fish shell; default to /bin/sh if not overriden.

Also Add in a warning notice when auto-changing the user's shell. This is meant to address https://github.com/JuliaLang/julia/issues/4918 so users don't have the option to break Julia with `fish`.