To allow me to run programs predictably, I have a script which wraps up rbenv exec and some environment variables.
RBENV_VERSION=1.9.3-p125 RBENV_GEMSET_NAMES=heroku rbenv exec heroku "$@"
I'm not sure if it would be useful to be able to have both a .rbenv-gemsets file and set the RBENV_GEMSET_NAMES environment var.
Allow setting the gemsets via the RBENV_GEMSET_NAMES environment vari…
Merged in, thanks!