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_bundler_version_finder.rb
    path of file: ./repos/artichoke/artichoke-backend/vendor/ruby/test/rubygems
    
    the code of the file until where you have to start completion: # frozen_string_literal: true
require_relative 'helper'

class TestGemBundlerVersionFinder < Gem::TestCase
  def setup
    super

    @argv = ARGV.dup
    @dollar_0 = $0
    without_any_upwards_gemfiles
  end

  def teardown
    ARGV.replace @argv
    $0 = @dollar_0

    super
  end


    
  def test_bundler_version
    assert_nil bvf.bundler_version
    bvf.stub(:lockfile_contents, "\n\nBUNDLED WITH\n   1.1.1.1\n") do
      assert_equal "1.1.1.1", bvf.bundler_version.to_s

      $0 = "bundle"
      ARGV.replace %w[update --bundler]
      assert_nil bvf.bundler_version

      ARGV.replace %w[update --bundler=1.1.1.2]
      assert_equal "1.1.1.2",  bvf.bundler_version.to_s

      ENV["BUNDLER_VERSION"] = "1.1.1.3"
      assert_equal "1.1.1.3", bvf.bundler_version.to_s
    end
  end