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: MatchData_test.rb
    path of file: ./repos/rbs/test/stdlib
    
    the code of the file until where you have to start completion: require_relative 'test_helper'

class MatchDataInstanceTest < Test::Unit::TestCase
  include TestHelper

  testing '::MatchData'

  INSTANCE = /[^q](?<a>.)(.)(?<b>.)/.match('qwerty')
  INSTANCE2 = /u\K(?<a>a)?./.match('uiop')

  def with_backref(name: 'a', idx: 1, &block)
    yield name.to_s
    yield name.to_sym
    with_int(idx, &block)
  end

  def test_initalize_copy
    instance = /./.match('&')

    
  def test_named_captures
    assert_send_type '() -> Hash[String, String]',
                     INSTANCE, :named_captures
    assert_send_type '() -> Hash[String, nil]',
                     INSTANCE2, :named_captures
    assert_send_type(
      '(symbolize_names: true) -> Hash[Symbol, String]',
      INSTANCE, :named_captures, symbolize_names: true
    )
    with_boolish do
      assert_send_type(
        '(symbolize_names: boolish) -> Hash[Symbol | String, String]',
        INSTANCE, :named_captures, symbolize_names: _1
      )
    end
  end