rubyv

#!/bin/bash
set -euf -o pipefail
out () { printf %s\\n "$*" ; }

##
# Choose a Ruby version
#
# Contact: Joel Parker Henderson (joel@joelparkerhenderson.com)
# License: GPL
# Updated: 2015-01-25
##

help()
{
cat << EOF
ruby-v

usage: $0 [options]

Ruby version chooser for our specific systems.

This script is tightly coupled to our systems;
if you are looking for a general-purpose solution,
we suggest using `chruby` along with `ruby-install`.

Example:

    source rubyv mri 2.1.5

Options:

   -h      Show this help message
   -l      List versions in /opt/ruby
   -v      Verbose messages

We install Ruby runtimes and versions here:

    /opt/ruby/<runtime>/<version>
    /opt/gems/<runtime>/<version>

Examples:

    /opt/ruby/mri/2.1.5
    /opt/ruby/jruby/1.7.16.1
    /opt/ruby/rbx/2.3.0

This script modifies three environment variables:

    PATH: replaces /opt/ruby/<runtime>/<version> and /opt/gems/<runtime>/<version>/
    GEM_HOME: changes it to /opt/gems/<runtime>/<version>
    GEM_PATH: changes it to be identical to GEM_HOME

EOF
}

RUBY_TOP_DIR=/opt/ruby
GEMs_TOP_DIR=/opt/gems

VERBOSE=
while getopts “hlv” option
do
     case "$option" in
         h)
             help
             exit 1
             ;;
	 l)
             ls -l $RUBY_TOP_DIR | awk '{print $9,$10,$11;}' | grep \\w
             ls -l $GEMS_TOP_DIR | awk '{print $9,$10,$11;}' | grep \\w
             exit 1
             ;;
         v)
             VERBOSE=1
             ;;
         ?)
             help
             exit
             ;;
     esac
done
shift $(($OPTIND - 1))

VERSION=$1

export PATH=`out $PATH | sed "s#:$RUBY_TOP_DIR/[^/]*/#:$RUBY_TOP_DIR/$VERSION/#; s#:$GEM_TOP_DIR/[^/]*/#:$GEM_TOP_DIR/$VERSION/#"`

export GEM_HOME=$GEM_TOP_DIR/$VERSION
export GEM_PATH=`out $GEM_PATH | sed "s#$GEM_TOP_DIR/[^:]*#$GEM_TOP_DIR/$VERSION#"`

if [ "$VERBOSE" = "1" ]; then
   out "PATH=$PATH"
   out "GEM_HOME=$GEM_HOME"
   out "GEM_PATH=$GEM_PATH"
fi