Helper script to create a Ruby app folder (w/ a '.versions.conf' file) and configure RVM

rvm_proj_new.sh

#!/usr/bin/env bash
me="$(basename "$(test -L "$0" && readlink "$0" || echo "$0")")"
# echo $me
if [ -z "$1" ] || [ -z "$2" ] || [ -z "$3" ] || [ -z "$4" ]
then
  echo
  echo 'To create a Ruby app folder and configure it for RVM usage, use the following syntax:'
  echo
  echo '  bash --login './$me 'PROJ_ROOT PROJ_NAME PROJ_RUBY_VER PROJ_GEMSET_NAME'
  echo
  echo 'This will also:'
  echo '  * Create a ".versions.conf" RVM config file w/ the specified Ruby version and gemset name'
  echo '  * Install the specified version of Ruby (if not yet installed)'
  echo '  * Switch to the specified Ruby version'
  echo '  * Install bundler gem in the global gemset (if not yet installed)'
  echo '  * Create a gemset for the specified gemset name'
  echo '  * Switch to the specified gemset'
  echo
  echo 'See "https://rvm.io/workflow/projects" for more RVM config info.'
  echo
else
  PROJ_ROOT=$1
  PROJ_NAME=$2
  PROJ_RUBY_VER=$3
  PROJ_GEMSET_NAME=$4

  PROJ_PATH=$PROJ_ROOT/$PROJ_NAME
  PROG_RV_GN=$PROJ_RUBY_VER@$PROJ_GEMSET_NAME

  echo 'Adding path:' $PROJ_PATH
  mkdir -p $PROJ_PATH
  cd $PROJ_PATH

  PROJ_FULL_PATH=$pwd

  echo 'Adding Bundler to:' $PROJ_RUBY_VER@global
  rm .versions.conf
  rvm --create --versions-conf $PROJ_RUBY_VER@global
  cd ..
  cd $PROJ_FULL_PATH

  # $rvm_recommended_ruby # broken?
  # See "https://github.com/rvm/rvm/issues/3158"
  rvm install $PROJ_RUBY_VER
  rvm use $PROJ_RUBY_VER
  
  rvm gemset use global
  gem install bundler

  echo 'Adding gemset:' $PROG_RV_GN
  rm .versions.conf
  rvm --create --versions-conf $PROG_RV_GN
  cd ..
  cd $PROJ_FULL_PATH
  touch Gemfile
fi