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_gem_ext_builder.rb
    path of file: ./repos/ruby-packer/ruby/test/rubygems
    
    the code of the file until where you have to start completion: # frozen_string_literal: true
require 'rubygems/test_case'
require 'rubygems/ext'
require 'rubygems/installer'

class TestGemExtBuilder < Gem::TestCase

  def setup
    super

    @ext = Fi
    
  def test_initialize
    build_info_dir = File.join @gemhome, 'build_info'

    FileUtils.mkdir_p build_info_dir

    build_info_file = File.join build_info_dir, "#{@spec.full_name}.info"

    File.open build_info_file, 'w' do |io|
      io.puts '--with-foo-dir=/nonexistent'
    end

    builder = Gem::Ext::Builder.new @spec

    assert_equal %w[--with-foo-dir=/nonexistent], builder.build_args
  end