You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: test_rubygems.rb
    path of file: ./repos/artichoke/artichoke-backend/vendor/ruby/test/rubygems
    
    the code of the file until where you have to start completion: require_relative 'helper'

class GemTest < Gem::TestCase
  def test_rubygems_normal_behaviour
    _ = Gem::Util.popen(*ruby_with_rubygems_in_load_path, '-e', "'require \"rubygems\"'", {:err => [:child, :out]}).strip
    as
    
  def test_operating_system_customizing_default_dir
    pend "does not apply to truffleruby" if RUBY_ENGINE == 'truffleruby'
    pend "loads a custom defaults/jruby file that gets in the middle" if RUBY_ENGINE == 'jruby'

    # On a non existing default dir, there should be no gems

    path = util_install_operating_system_rb <<-RUBY
      module Gem
        def self.default_dir
          File.expand_path("foo")
        end
      end