Switch rvm after git checkout

RVM Git post-checkout hook

#!/bin/bash

#Filename: .git/hooks/post-checkout
#Note: make sure to chmod +x post-checkout

CURRENT=`git branch --no-color 2> /dev/null | sed -e '/^[^*]/d' -e 's/* \(.*\)/\\ \1/'`

if [ $CURRENT = "upgrade" ]; then
  rvm use r19
else
  rvm use system
fi

Wayne pointed me to .rvmrc... even easier:

http://rvm.beginrescueend.com/workflow/rvmrc/#project

And he mentioned using "cd ." in the hook, to trigger loading of project rvmrc file. Though the hook may not be needed at all, with proper use of .rvmrc.

Better yet: http://gehling.dk/2015/09/automatic-change-rvm-environment-when-switching-git-branch/