rbenv: How to update list of available Ruby versions on Linux
When you tell rbenv to install a Ruby it does not know about, you will get an error message.
$ rbenv install 2.1.2 ruby-build: definition not found: 2.1.2 You can list all available versions with `rbenv install --list'. If the version you're looking for is not present, first try upgrading ruby-build. If it's still missing, open a request on the ruby-build issue tracker: https://github.com/sstephenson/ruby-build/issues
(Fun fact: Recent versions of ruby-build will give you a more helpful error message which just tells you the following.)
On Linux, you probably installed
ruby-build as an rbenv plugin. Updating is easy:
cd ~/.rbenv/plugins/ruby-build git pull
Done. Rbenv will know about the new versions immediately.