expect: svctest.MakeService("foo", svctest.SetClusterIPs("10.0.0.1"),
			svctest.SetIPFamilyPolicy(api.IPFamilyPolicySingleStack),
			svctest.SetIPFamilies(api.IPv4Protocol)),
	}, {
		name:  "single v6",
		input: svctest.MakeService("foo", svctest.SetClusterIPs("2000::1")),
		expect: svctest.MakeService("foo", svctest.SetClusterIPs("2000::1"),
			svctest.SetIPFamilyPolicy(api.IPFamilyPolicySingleStack),
			svctest.SetIPFamilies(api.IPv6Protocol)),

func SetIPFamilies(families ...api.IPFamily) Tweak {
	return func(svc *api.Service) {
		svc.Spec.IPFamilies = families
	}
}

// SetIPFamilyPolicy sets the service IPFamilyPolicy field.
func SetIPFamilyPolicy(policy api.IPFamilyPolicy) Tweak {
	return func(svc *api.Service) {
		svc.Spec.IPFamilyPolicy = &policy
	}
}