// to be greater than or equal to 4.4.
func TestDualStackTCPListener(t *testing.T) {
	switch runtime.GOOS {
	case "plan9":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	if !supportsIPv4() || !supportsIPv6() {
		t.Skip("both IPv4 and IPv6 are required")
	}

	for _, tt := range dualStackTCPListenerTests {
		if !testableListenArgs(tt.network1, JoinHostPort(tt.address1, "0"), "") {

	{ipv6only, []IPAddr{{IP: IPv4(127, 0, 0, 1)}}, testInetaddr, nil, nil, nil, &AddrError{errNoSuitableAddress.Error(), "ADDR"}},
}

func TestAddrList(t *testing.T) {
	if !supportsIPv4() || !supportsIPv6() {
		t.Skip("both IPv4 and IPv6 are required")
	}

	for i, tt := range addrListTests {
		addrs, err := filterAddrList(tt.filter, tt.ips, tt.inetaddr, "ADDR")
		if !reflect.DeepEqual(err, tt.err) {

	"fmt"
	"internal/testenv"
	"net/netip"
	"os"
	"reflect"
	"runtime"
	"testing"
	"time"
)

func BenchmarkUDP6LinkLocalUnicast(b *testing.B) {
	testHookUninstaller.Do(uninstallTestHooks)

	if !supportsIPv6() {
		b.Skip("IPv6 is not supported")
	}
	ifi := loopbackInterface()
	if ifi == nil {
		b.Skip("loopback interface not found")
	}
	lla := ipv6LinkLocalUnicastAddr(ifi)
	if lla == "" {

		resolveIPAddrTests = append(resolveIPAddrTests, []resolveIPAddrTest{
			{"ip", "localhost", &IPAddr{IP: IPv4(127, 0, 0, 1)}, nil},
			{"ip4", "localhost", &IPAddr{IP: IPv4(127, 0, 0, 1)}, nil},
		}...)
	}

	if supportsIPv6() {
		resolveTCPAddrTests = append(resolveTCPAddrTests, resolveTCPAddrTest{"tcp6", "localhost:3", &TCPAddr{IP: IPv6loopback, Port: 3}, nil})

	"8.8.8.8",
	"8.8.4.4",
	"2001:4860:4860::8888",
	"2001:4860:4860::8844",
}

func TestLookupGooglePublicDNSAddr(t *testing.T) {
	mustHaveExternalNetwork(t)

	if !supportsIPv4() || !supportsIPv6() || !*testIPv4 || !*testIPv6 {
		t.Skip("both IPv4 and IPv6 are required")
	}

	defer dnsWaitGroup.Wait()

	for _, ip := range lookupGooglePublicDNSAddrTests {
		names, err := LookupAddr(ip)

}

// SupportsIPv4 returns true if proxy supports IPv4 addresses.
func (node *Proxy) SupportsIPv4() bool {
	return node.ipMode == IPv4 || node.ipMode == Dual
}

// SupportsIPv6 returns true if proxy supports IPv6 addresses.
func (node *Proxy) SupportsIPv6() bool {
	return node.ipMode == IPv6 || node.ipMode == Dual
}

// IsIPv6 returns true if proxy only supports IPv6 addresses.
func (node *Proxy) IsIPv6() bool {

	}
}

func TestDialAddrError(t *testing.T) {
	switch runtime.GOOS {
	case "plan9":
		t.Skipf("not supported on %s", runtime.GOOS)
	}

	if !supportsIPv4() || !supportsIPv6() {
		t.Skip("both IPv4 and IPv6 are required")
	}

	for _, tt := range []struct {
		network string
		lit     string
		addr    *TCPAddr
	}{
		{"tcp4", "::1", nil},

}

// IsIPv6 returns true if proxy only supports IPv6 addresses.
func (node *Proxy) IsIPv6() bool {
	return node.ipMode == model.IPv6
}

func (node *Proxy) SupportsIPv6() bool {
	return node.ipMode == model.IPv6 || node.ipMode == model.Dual
}

const (
	serviceNodeSeparator = "~"
)

func (node *Proxy) ServiceNode() string {
	ip := ""

			if node.SupportsIPv4() && s.AutoAllocatedIPv4Address != "" {
				return s.AutoAllocatedIPv4Address
			}
			if node.SupportsIPv6() && s.AutoAllocatedIPv6Address != "" {
				return s.AutoAllocatedIPv6Address
			}
		}
	}

	return s.DefaultAddress
}