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_ast.rb
    path of file: ./repos/artichoke/artichoke-backend/vendor/ruby/test/ruby
    
    the code of the file until where you have to start completion: # frozen_string_literal: false
require 'test/unit'
require 'tempfile'

class RubyVM
  module AbstractSyntaxTree
    class Node
      class CodePosition
        include Comparabl
    
  def test_dstr
    node = parse('"foo#{1}bar"')
    _, _, body = *node.children
    assert_equal(:DSTR, body.type)
    head, body = body.children
    assert_equal("foo", head)
    assert_equal(:EVSTR, body.type)
    body, = body.children
    assert_equal(:LIT, body.type)
    assert_equal([1], body.children)
  end