bundle-local.sh

# Script for switching your own gems in and out of a project
# without interfering with git's status. Caveat emptor.

# Instructions:
#  Source this file from your .bashrc, this will make bundle-local available
#  Put a Gemfile.local in your project with the gems you want to use
#  run `bundle-local on && bundle` from your project directory
#  run `bundle-local off` if you are going to need to check in changes to your bundle

bundle-local ()
{
    local command="$1";
    if [ "$command" = "on" ]; then
        if ! grep --color=auto -qs Gemfile.local Gemfile; then
            echo "Appending local gems to gemfile..."
            echo "eval File.read('Gemfile.local')" >> Gemfile;
            echo "Telling git to ignore gemfile changes..."
            git update-index --assume-unchanged Gemfile Gemfile.lock;
            echo "Updating bundles..."
            bundle;
        fi;
    else
        if [ "$command" = "off" ]; then
            echo "Appending local gems to gemfile..."
            sed -i '/Gemfile.local/d' Gemfile;
            echo "Telling git not to ignore gemfile changes..."
            git update-index --no-assume-unchanged Gemfile Gemfile.lock;
            echo "Updating bundles..."
            bundle;
        else
            echo "Usage: bundle-local <on|off>" 1>&2;
            return 1;
        fi;
    fi
}

Gemfile.local

group :development do
  gem 'debugger'
  gem 'spring'
end

group :test do
  gem 'minitest', '4.3.0'
  gem 'tconsole', '1.2.8'
end