class Bundler::CLI

def exec(*)
  ARGV.delete('exec')
  # Set PATH
  paths = (ENV['PATH'] || "").split(File::PATH_SEPARATOR)
  paths.unshift "#{Bundler.bundle_path}/bin"
  ENV["PATH"] = paths.uniq.join(File::PATH_SEPARATOR)
  # Set BUNDLE_GEMFILE
  ENV['BUNDLE_GEMFILE'] = Bundler::SharedHelpers.default_gemfile.to_s
  # Set RUBYOPT
  locked_env = Bundler.root.join(".bundle/environment.rb")
  rubyopt = [ENV["RUBYOPT"]].compact
  if locked_env.exist?
    rubyopt.unshift "-r#{locked_env.to_s}"
  else
    rubyopt.unshift "-rbundler/setup"
    rubyopt.unshift "-I#{File.expand_path('../..', __FILE__)}"
  end
  ENV["RUBYOPT"] = rubyopt.join(' ')
  # Run
  Kernel.exec *ARGV
end