'When you set a \'memswap_limit\' it is invalid config unless you also set
a mem_limit'

def test_validation_fails_with_just_memswap_limit(self):

    with pytest.raises(ConfigurationError) as excinfo:
        config.load(build_config_details({u'foo': {u'image': u'busybox', u'memswap_limit': 2000000}}, u'tests/fixtures/extends', u'filename.yml'))
    assert (u"foo.memswap_limit    is    invalid:    when    defining    'memswap_limit'    you    must    set    'mem_limit'    as    well" in excinfo.exconly())
