Install Ruby 2.2 on OS X Yosemite with Fish shell

ruby-install

brew update
brew install chruby chruby-fish ruby-install openssl readline libyaml gdbm libffi
# Optional:
brew cleanup

# https://github.com/raggi/openssl-osx-ca
brew tap raggi/ale
brew install openssl-osx-ca

echo ". /usr/local/share/chruby/chruby.fish" >> .config/fish/config.fish
echo ". /usr/local/share/chruby/auto.fish"   >> .config/fish/config.fish

ruby-install ruby 2.2.2

echo "ruby-2.2" > .ruby-version

# Restart shell
# If warnings such as "set: Warning: path component...", see https://github.com/JeanMertz/chruby-fish#known-issues

ruby -v # => ruby 2.2.2p95 (2015-04-13 revision 50295) [x86_64-darwin14]

gem update --system
gem --version # > 2.0.0
gem install bundler