A simple CocoaPods version manager.

podenv.rb

#!/usr/bin/env ruby

require 'rubygems'
require 'yaml'

def install_gem(name, version)
	require 'rubygems/commands/install_command'
	cmd = Gem::Commands::InstallCommand.new
	cmd.handle_options [name, '--version', version]
	begin
		cmd.execute
	rescue Gem::SystemExitException => e
		e.exit_code == 0
	end
end

if File.exist?('Podfile.lock')
	lockfile = YAML.load(File.read('Podfile.lock'))
	version = lockfile['COCOAPODS']

	begin
		gem 'cocoapods', "=#{version}"
	rescue Gem::LoadError
		puts "Auto-installing CocoaPods #{version}"
		exit(1) unless install_gem('cocoapods', version)

		begin
			gem 'cocoapods', "=#{version}"
		rescue Gem::LoadError => message
			STDERR.puts message
			exit(1)
		end
	end
end

require 'cocoapods'

Pod::Command.run(ARGV)