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_case.rb
    path of file: ./repos/truffleruby/test/mri/tests/rdoc/support
    
    the code of the file until where you have to start completion: require 'bundler/errors'
begin
  gem 'test-unit'
rescue NoMethodError, Gem::LoadError, Bundler::GemfileNotFound
  # for ruby tests
end

require 'test/unit'

require 'fileutils'
require 'pp'
require 'tempfile'
require 'tmpdir'
require 'stringio'

require_relative '../../../lib/rdoc'

##
# RDoc::TestCase is an abstract TestCase to provide common setup and teardown
# across all RDoc tests.  The test case uses test-unit, so all the assertions
# of test-unit may be used.
#
# The testcase provides the following:
#
# * A reset code-object tree
# * A reset markup preprocessor (RDoc::Markup::PreProcess)
# * The <code>@RM</code> alias of RDoc::Markup (for 
    
  def setup
    super

    @orig_home = ENV["HOME"]
    FileUtils.mkdir_p(@test_home = Dir.mktmpdir("test_rdoc_"))
    ENV["HOME"] = @test_home

    @top_level = nil

    @RM = RDoc::Markup

    @pwd = Dir.pwd

    @store = RDoc::Store.new

    @rdoc = RDoc::RDoc.new
    @rdoc.store = @store
    @rdoc.options = RDoc::Options.new

    g = Object.new
    def g.class_dir() end
    def g.file_dir() end
    @rdoc.generator = g

    RDoc::Markup::PreProcess.reset
  end

  ##
  # Abstract test-case teardown

  def teardown
    ENV["HOME"] = @orig_home if defined?(@orig_home)
    defined?(@test_home) and FileUtils.rm_rf @test_home

    super
  end

  ##
  # Asserts +path+ is a file

  def assert_file path
    assert File.file?(path), "#{path} is not a file"
  end

  ##
  # Asserts +path+ is a directory

  def assert_directory path
    assert File.directory?(path), "#{path} is not a directory"
  end

  ##
  # Refutes +path+ exists

  def refute_file path
    refute File.exist?(path), "#{path} exists"
  end

  ##
  # Shortcut for RDoc::Markup::BlankLine.new

  def blank_line
    @RM::BlankLine.new
  end

  ##
  # Shortcut for RDoc::Markup::BlockQuote.new with +contents+

  def block *contents
    @RM::BlockQuote.new(*contents)
  end

  ##
  # Creates an RDoc::Comment with +text+ which was defined on +top_level+.
  # By default the comment has the 'rdoc' format.

  def comment text, top_level = @top_level, language = nil
    comment = RDoc::Comment.new text, top_level, language
    comment
  end

  ##
  # Shortcut for RDoc::Markup::Document.new with +contents+

  def doc *contents
    @RM::Document.new(*contents)
  end

  ##
  # Shortcut for RDoc::Markup::HardBreak.new

  def hard_break
    @RM::HardBreak.new
  end

  ##
  # Shortcut for RDoc::Markup::Heading.new with +level+ and +text+

  def head level, text
    @RM::Heading.new level, text
  end

  ##
  # Shortcut for RDoc::Markup::ListItem.new with +label+ and +parts+

  def item label = nil, *parts
    @RM::ListItem.new label, *parts
  end

  ##
  # Shortcut for RDoc::Markup::List.new with +type+ and +items+

  def list type = nil, *items
    @RM::List.new type, *items
  end

  ##
  # Enables pretty-print output

  def mu_pp obj # :nodoc:
    s = obj.pretty_inspect
    s = RDoc::Encoding.change_encoding s, Encoding.default_external
    s.chomp
  end

  ##
  # Shortcut for RDoc::Markup::Paragraph.new with +contents+

  def para *a
    @RM::Paragraph.new(*a)
  end

  ##
  # Shortcut for RDoc::Markup::Rule.new with +weight+

  def rule weight
    @RM::Rule.new weight
  end

  ##
  # Shortcut for RDoc::Markup::Raw.new with +contents+

  def raw *contents
    @RM::Raw.new(*contents)
  end

  ##
  # Creates a temporary directory changes the current directory to it for the
  # duration of the block.
  #
  # Depends upon Dir.mktmpdir

  def temp_dir
    Dir.mktmpdir do |temp_dir|
      Dir.chdir temp_dir do
        yield temp_dir
      end
    end
  end

  ##
  # Shortcut for RDoc::Markup::Verbatim.new with +parts+

  def verb *parts
    @RM::Verbatim.new(*parts)
  end

  ##
  # run capture_io with setting $VERBOSE = true

  def verbose_capture_output
    capture_output do
      begin
        orig_verbose = $VERBOSE
        $VERBOSE = true
        yield
      ensure
        $VERBOSE = orig_verbose
      end
    end
  end
end