all: sync with master; upd chlog

internal/rdns/rdns_test.go

@@ -0,0 +1,105 @@
+package rdns_test
+
+import (
+	"net/netip"
+	"testing"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/rdns"
+	"github.com/AdguardTeam/golibs/netutil"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// fakeRDNSExchanger is a mock [rdns.Exchanger] implementation for tests.
+type fakeRDNSExchanger struct {
+	OnExchange func(ip netip.Addr) (host string, err error)
+}
+
+// type check
+var _ rdns.Exchanger = (*fakeRDNSExchanger)(nil)
+
+// Exchange implements [rdns.Exchanger] interface for *fakeRDNSExchanger.
+func (e *fakeRDNSExchanger) Exchange(ip netip.Addr) (host string, err error) {
+	return e.OnExchange(ip)
+}
+
+func TestDefault_Process(t *testing.T) {
+	ip1 := netip.MustParseAddr("1.2.3.4")
+	revAddr1, err := netutil.IPToReversedAddr(ip1.AsSlice())
+	require.NoError(t, err)
+
+	ip2 := netip.MustParseAddr("4.3.2.1")
+	revAddr2, err := netutil.IPToReversedAddr(ip2.AsSlice())
+	require.NoError(t, err)
+
+	localIP := netip.MustParseAddr("192.168.0.1")
+	localRevAddr1, err := netutil.IPToReversedAddr(localIP.AsSlice())
+	require.NoError(t, err)
+
+	config := &rdns.Config{
+		CacheSize: 100,
+		CacheTTL:  time.Hour,
+	}
+
+	testCases := []struct {
+		name string
+		addr netip.Addr
+		want string
+	}{{
+		name: "first",
+		addr: ip1,
+		want: revAddr1,
+	}, {
+		name: "second",
+		addr: ip2,
+		want: revAddr2,
+	}, {
+		name: "empty",
+		addr: netip.MustParseAddr("0.0.0.0"),
+		want: "",
+	}, {
+		name: "private",
+		addr: localIP,
+		want: localRevAddr1,
+	}}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			hit := 0
+			onExchange := func(ip netip.Addr) (host string, err error) {
+				hit++
+
+				switch ip {
+				case ip1:
+					return revAddr1, nil
+				case ip2:
+					return revAddr2, nil
+				case localIP:
+					return localRevAddr1, nil
+				default:
+					return "", nil
+				}
+			}
+			exchanger := &fakeRDNSExchanger{
+				OnExchange: onExchange,
+			}
+
+			config.Exchanger = exchanger
+			r := rdns.New(config)
+
+			got, changed := r.Process(tc.addr)
+			require.True(t, changed)
+
+			assert.Equal(t, tc.want, got)
+			assert.Equal(t, 1, hit)
+
+			// From cache.
+			got, changed = r.Process(tc.addr)
+			require.False(t, changed)
+
+			assert.Equal(t, tc.want, got)
+			assert.Equal(t, 1, hit)
+		})
+	}
+}