refactor-for-testability (#3)

Co-authored-by: jdl <jdl@desktop>
Co-authored-by: jdl <jdl@crumpington.com>
Reviewed-on: #3

peer/packets_test.go

@@ -0,0 +1,66 @@
+package peer
+
+import (
+	"crypto/rand"
+	"net/netip"
+	"reflect"
+	"testing"
+)
+
+func TestSynPacket(t *testing.T) {
+	p := packetSyn{
+		TraceID: newTraceID(),
+		//SentAt:        time.Now().UnixMilli(),
+		//SharedKeyType: 1,
+		Direct: true,
+	}
+	rand.Read(p.SharedKey[:])
+
+	p.PossibleAddrs[0] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{1, 2, 3, 4}), 234)
+	p.PossibleAddrs[1] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{2, 2, 3, 4}), 12399)
+	p.PossibleAddrs[2] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{3, 2, 3, 4}), 60000)
+
+	buf := p.Marshal(newBuf())
+	p2, err := parsePacketSyn(buf)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(p, p2) {
+		t.Fatal(p2)
+	}
+}
+
+func TestAckPacket(t *testing.T) {
+	p := packetAck{
+		TraceID: newTraceID(),
+		ToAddr:  netip.AddrPortFrom(netip.AddrFrom4([4]byte{1, 2, 3, 4}), 234),
+	}
+
+	p.PossibleAddrs[0] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{8, 2, 3, 4}), 100)
+	p.PossibleAddrs[1] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{2, 2, 3, 4}), 12399)
+	p.PossibleAddrs[2] = netip.AddrPortFrom(netip.AddrFrom4([4]byte{3, 2, 3, 4}), 60000)
+
+	buf := p.Marshal(newBuf())
+	p2, err := parsePacketAck(buf)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(p, p2) {
+		t.Fatal(p2)
+	}
+}
+
+func TestProbePacket(t *testing.T) {
+	p := packetProbe{
+		TraceID: newTraceID(),
+	}
+
+	buf := p.Marshal(newBuf())
+	p2, err := parsePacketProbe(buf)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(p, p2) {
+		t.Fatal(p2)
+	}
+}