module Kernel
  def silence_warnings
    with_warnings(nil) { yield }
  end

  def with_warnings(flag)
    old_verbose, $VERBOSE = $VERBOSE, flag
    yield
  ensure
    $VERBOSE = old_verbose
  end
end unless Kernel.respond_to? :silence_warnings

module Kernel
  def silence_stream(stream)
    old_stream = stream.dup
    stream.reopen(RbConfig::CONFIG['host_os'] =~ /mswin|mingw/ ? 'NUL:' : '/dev/null')
    stream.sync = true
    yield
  ensure
    stream.reopen(old_stream)
  end
end unless Kernel.respond_to? :silence_stream