def test_should_return_none_if_no_new_process_group(self):
		mock_os = mock.Mock(spec=['setsid'])
		eq_(utils._required_preexec(False, mock_os), None)
	def test_should_return_none_if_setsid_unavailable(self):
		mock_os = mock.Mock(spec=['setsid'])
		eq_(utils._required_preexec(False, mock_os), None)
	def test_should_return_setsid_if_new_process_group_requested_and_setsid_available(self):
		mock_os = mock.Mock(spec=['setsid'])
		eq_(utils._required_preexec(True, mock_os), mock_os.setsid)