ruby_noexec_wrapper

#!/usr/bin/env ruby

original_file=ARGV[0]
ARGV.shift
$PROGRAM_NAME=original_file

require 'rubygems'
begin
  require 'rubygems-bundler/noexec'
  puts $:
rescue LoadError
  warn "unable to load rubygems-bundler/noexec" if ENV.key?('NOEXEC_DEBUG')
end

eval File.read(original_file), binding, original_file

rubygems_plugin.rb

def rubygems_bundler_spec_version
  rubygems_bundler_spec =
    if Gem::Specification.respond_to?(:find_by_name)
      Gem::Specification.find_by_name("rubygems-bundler")
    else
      Gem.source_index.find_name("rubygems-bundler").last
    end
  rubygems_bundler_spec ? rubygems_bundler_spec.version : nil
rescue Gem::LoadError
end

called_path, called_version = __FILE__.match(/^(.*\/rubygems-bundler-([^\/]+)\/lib).*$/)[1..2]

# continue only if loaded ($: or gem) and called versions is the same and not shared gems disabled in bundler
if
  ( $:.include?(called_path) || rubygems_bundler_spec_version.to_s == called_version ) and
  ( !defined?(Bundler) || ( defined?(Bundler) && Bundler::SharedHelpers.in_bundle? && !Bundler.settings[:disable_shared_gems]) )

  require 'rubygems/version'
  require 'rubygems-bundler/wrapper'

  # Set the custom_shebang if user did not set one
  Gem.pre_install do |inst|
    Gem.configuration[:custom_shebang] ||= '$env ruby_noexec_wrapper'
    RubygemsBundler::Wrapper.install
  end

  if Gem::Version.new(Gem::VERSION) < Gem::Version.new('2.0') then
    # Add custom_shebang support to rubygems
    require 'rubygems-bundler/rubygems_bundler_installer'
  end

  require 'rubygems-bundler/regenerate_binstubs_command'
  Gem::CommandManager.instance.register_command :regenerate_binstubs
elsif ENV.key?('NOEXEC_DEBUG')
  msg = "Older rubygems-bundler found, loaded: #{rubygems_bundler_spec.version}, called: #{called_version}, you can uninstall it with:\n\n    "

  error_source = __FILE__
  gem_source = File.expand_path("../../../..", error_source)
  gem_version = error_source.sub(/^.*\/rubygems-bundler-([^\/]+)\/.*$/,'\1')

  if ENV['GEM_HOME'] or ENV['GEM_PATH']
    msg << "GEM_HOME=\"#{gem_source}\" " unless ENV['GEM_HOME'] == gem_source
  end

  msg << "gem uninstall -ax rubygems-bundler -v #{gem_version}\n\n"

  puts msg
end