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_dns.rb
    path of file: ./repos/jruby/test/mri/resolv
    
    the code of the file until where you have to start completion: # frozen_string_literal: false
require 'test/unit'
require 'resolv'
require 'socket'
require 'tempfile'

class Object # :nodoc:
  def stub name, val_or_callable, &block
    new_name = "__minitest_stub__#{name}"

    metaclass = class << self; self; end

    if respond_to? name and not methods.map(&:to_s).include? name.to_s then
      metaclass.send :define_method, name do |*args|
        super(*args)
      end
    end

    metaclass.send :alias_method, new_name, name

    metaclass.send :define_method, name do |*args|
      if val_or_callable.respond_to? :call then
        val_or_callable.call(*args)
      else
        val_or_callable
      end
    end

    yield self
  ensure
    metaclass.send :undef_method, name
    metaclass.send :alias_method, name, new_name
    metaclass.send :undef_method, new_name
  end unless method_defined?(:stub) # lib/rubygems/test_case.rb also has the same method definition
end

class TestResolvDNS < Test::Unit::TestCase
  def setup
    @save_do_not_reverse_lookup = BasicSocket.do_not_reverse_lookup
    BasicSocket.do_not_reverse_lookup = true
  end

  def teardown
    BasicSocket.do_not_reverse_lookup = @save_do_not_reverse_lookup
  end

  def with_udp(host, port)
    u = UDPSocket.new
    begin
      u.bind(host, port)
      yield u
    ensure
      u.close
    end
  end

  # [ruby-core:65836]
  def test_resolve_with_2_ndots
    conf = Resolv::DNS::Config.new :nameserver => ['127.0.0.1'], :ndots => 2
    assert conf.single?

    candidates = []
    conf.resolv('example.com') { |candidate, *args|
      candidates << candidate
      raise Resolv::DNS::Config::NXDomain
    }
    n = Resolv::DNS::Name.create 'example.com.'
    assert_equal n, candidates.last
  end

  def test_query_ipv4_address
    begin
      OpenSSL
    rescue LoadError
      skip 'autoload problem. see [ruby-dev:45021][Bug #5786]'
    end if defined?(OpenSSL)

    with_udp('127.0.0.1', 0) {|u|
      _, server_port, _, server_address = u.addr
      begin
        client_thread = Thread.new {
          Resolv::DNS.open(:nameserver_port => [[server_address, server_port]]) {|dns|
            dns.getresources("foo.example.org", Resolv::DNS::Resource::IN::A)
          }
        }
        server_thread = Thread.new {
          msg, (_, client_port, _, client_address) = Timeout.timeout(5) {u.recvfrom(4096)}
          id, word2, qdcount, ancount, nscount, arcount = msg.unpack("nnnnnn")
          qr =     (word2 & 0x8000) >> 15
          opcode = (word2 & 0x7800) >> 11
          aa =     (word2 & 0x0400) >> 10
          tc =     (word2 & 0x0200) >> 9
          rd =     (word2 & 0x0100) >> 8
          ra =     (word2 & 0x0080) >> 7
          z =      (word2 & 0x0070) >> 4
          rcode =   word2 & 0x000f
          rest = msg[12..-1]
          assert_equal(0, qr) # 0:query 1:response
          assert_equal(0, opcode) # 0:QUERY 1:IQUERY 2:STATUS
          assert_equal(0, aa) # Authoritative Answer
          assert_equal(0, tc) # TrunCation
          assert_equal(1, rd) # Recursion Desired
          assert_equal(0, ra) # Recursion Available
          assert_equal(0, z) # Reserved for future use
          assert_equal(0, rcode) # 0:No-error 1:Format-error 2:Server-failure 3:Name-Error 4:Not-Implemented 5:Refused
          assert_equal(1, qdcount) # number of entries in the question section.
          assert_equal(0, a
    
  def test_query_ipv4_duplicate_responses
    begin
      OpenSSL
    rescue LoadError
      skip 'autoload problem. see [ruby-dev:45021][Bug #5786]'
    end if defined?(OpenSSL)

    with_udp('127.0.0.1', 0) {|u|
      _, server_port, _, server_address = u.addr
      begin
        client_thread = Thread.new {
          Resolv::DNS.open(:nameserver_port => [[server_address, server_port]], :search => ['bad1.com', 'bad2.com', 'good.com'], ndots: 5) {|dns|
            dns.getaddress("example")
          }
        }
        server_thread = Thread.new {
          3.times do
            msg, (_, client_port, _, client_address) = Timeout.timeout(5) {u.recvfrom(4096)}
            id, flags, qdcount, ancount, nscount, arcount = msg.unpack("nnnnnn")

            qr =     (flags & 0x8000) >> 15
            opcode = (flags & 0x7800) >> 11
            aa =     (flags & 0x0400) >> 10
            tc =     (flags & 0x0200) >> 9
            rd =     (flags & 0x0100) >> 8
            ra =     (flags & 0x0080) >> 7
            z =      (flags & 0x0070) >> 4
            rcode =   flags & 0x000f
            _rest = msg[12..-1]

            questions = msg.bytes[12..-1]
            labels = []
            idx = 0
            while idx < questions.length-5
              size = questions[idx]
              labels << questions[idx+1..idx+size].pack('c*')
              idx += size+1
            end
            hostname = labels.join('.')

            if hostname == "example.good.com"
              id = id
              qr = 1
              opcode = opcode
              aa = 0
              tc = 0
              rd = rd
              ra = 1
              z = 0
              rcode = 0
              qdcount = 1
              ancount = 1
              nscount = 0
              arcount = 0
              word2 = (qr << 15) |
                      (opcode << 11) |
                      (aa << 10) |
                      (tc << 9) |
                      (rd << 8) |
                      (ra << 7) |
                      (z << 4) |
                      rcode
              msg = [id, word2, qdcount, ancount, nscount, arcount].pack("nnnnnn")
              msg << questions.pack('c*')
              type = 1
              klass = 1
              ttl = 3600
              rdlength = 4
              rdata = [52,0,2,1].pack("CCCC")
              rr = [0xc00c, type, klass, ttl, rdlength, rdata].pack("nnnNna*")
              msg << rr
              rdata = [52,0,2,2].pack("CCCC")
              rr = [0xc00c, type, klass, ttl, rdlength, rdata].pack("nnnNna*")
              msg << rr

              u.send(msg, 0, client_address, client_port)
            else
              id = id
              qr = 1
              opcode = opcode
              aa = 0
              tc = 0
              rd = rd
              ra = 1
              z = 0
              rcode = 3
              qdcount = 1
              ancount = 0
              nscount = 0
              arcount = 0
              word2 = (qr << 15) |
                      (opcode << 11) |
                      (aa << 10) |
                      (tc << 9) |
                      (rd << 8) |
                      (ra << 7) |
                      (z << 4) |
                      rcode
              msg = [id, word2, qdcount, ancount, nscount, arcount].pack("nnnnnn")
              msg << questions.pack('c*')

              u.send(msg, 0, client_address, client_port)
              u.send(msg, 0, client_address, client_port)
            end