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_flush.rb
    path of file: ./repos/ruby-packer/ruby/test/io/nonblock
    
    the code of the file until where you have to start completion: # frozen_string_literal: false
require 'test/unit'
require 'timeout'
begin
 
    
  def test_flush
    IO.pipe {|r, w|
      return if flush_test(r, w)
    }
    require 'socket';
    Socket.pair(:INET, :STREAM) {|s1, s2|
      return if flush_test(s1, s2)
    }
    skip "nonblocking IO did not work"
  end