swarm Address better design

pkg/swarm/swarm.go

@@ -12,21 +12,31 @@ import (
 
 // Address represents an address in Swarm metric space of
 // Node and Chunk addresses.
-type Address []byte
+type Address struct {
+	b []byte
+}
+
+func NewAddress(b []byte) Address {
+	return Address{b: b}
+}
 
-// NewAddress returns an Address from a hex-encoded string representation.
-func NewAddress(s string) (Address, error) {
-	return hex.DecodeString(s)
+// ParseHexAddress returns an Address from a hex-encoded string representation.
+func ParseHexAddress(s string) (a Address, err error) {
+	b, err := hex.DecodeString(s)
+	if err != nil {
+		return a, err
+	}
+	return NewAddress(b), nil
 }
 
 // String returns a hex-encoded representation of the Address.
 func (a Address) String() string {
-	return hex.EncodeToString(a)
+	return hex.EncodeToString(a.b)
 }
 
 // Equal returns true if two addresses are identical.
 func (a Address) Equal(b Address) bool {
-	return bytes.Equal(a, b)
+	return bytes.Equal(a.b, b.b)
 }
 
 // IsZero returns true if the Address is not set to any value.
@@ -35,4 +45,4 @@ func (a Address) IsZero() bool {
 }
 
 // ZeroAddress is the address that has no value.
-var ZeroAddress = Address(nil)
+var ZeroAddress = NewAddress(nil)

pkg/swarm/swarm_test.go

@@ -5,7 +5,6 @@
 package swarm_test
 
 import (
-	"bytes"
 	"encoding/hex"
 	"errors"
 	"testing"
@@ -33,25 +32,25 @@ func TestAddress(t *testing.T) {
 		{
 			name: "zero",
 			hex:  "00",
-			want: []byte{0},
+			want: swarm.NewAddress([]byte{0}),
 		},
 		{
 			name: "one",
 			hex:  "01",
-			want: []byte{1},
+			want: swarm.NewAddress([]byte{1}),
 		},
 		{
 			name: "arbitrary",
 			hex:  "35a26b7bb6455cbabe7a0e05aafbd0b8b26feac843e3b9a649468d0ea37a12b2",
-			want: []byte{0x35, 0xa2, 0x6b, 0x7b, 0xb6, 0x45, 0x5c, 0xba, 0xbe, 0x7a, 0xe, 0x5, 0xaa, 0xfb, 0xd0, 0xb8, 0xb2, 0x6f, 0xea, 0xc8, 0x43, 0xe3, 0xb9, 0xa6, 0x49, 0x46, 0x8d, 0xe, 0xa3, 0x7a, 0x12, 0xb2},
+			want: swarm.NewAddress([]byte{0x35, 0xa2, 0x6b, 0x7b, 0xb6, 0x45, 0x5c, 0xba, 0xbe, 0x7a, 0xe, 0x5, 0xaa, 0xfb, 0xd0, 0xb8, 0xb2, 0x6f, 0xea, 0xc8, 0x43, 0xe3, 0xb9, 0xa6, 0x49, 0x46, 0x8d, 0xe, 0xa3, 0x7a, 0x12, 0xb2}),
 		},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
-			a, err := swarm.NewAddress(tc.hex)
+			a, err := swarm.ParseHexAddress(tc.hex)
 			if !errors.Is(err, tc.wantErr) {
 				t.Fatalf("got error %v, want %v", err, tc.wantErr)
 			}
-			if !bytes.Equal(a, tc.want) {
+			if a.String() != tc.want.String() {
 				t.Errorf("got address %#v, want %#v", a, tc.want)
 			}
 			if !a.Equal(tc.want) {