Be consistent in how we encode stringy types

Namely as []byte slices

iri.go

@@ -98,7 +98,7 @@ func (i *IRI) GobDecode(data []byte) error {
 		// NOTE(marius): this behaviour diverges from vanilla gob package
 		return nil
 	}
-	var bb string
+	var bb []byte
 	if err := gob.NewDecoder(bytes.NewReader(data)).Decode(&bb); err != nil {
 		return err
 	}

iri_test.go

@@ -332,7 +332,7 @@ func TestIRI_GobDecode(t *testing.T) {
 		{
 			name:    "some iri",
 			i:       "https://example.com",
-			data:    gobValue("https://example.com"),
+			data:    gobValue([]byte("https://example.com")),
 			wantErr: false,
 		},
 	}

link.go

@@ -3,9 +3,6 @@ package activitypub
 import (
 	"bytes"
 	"encoding/gob"
-	"errors"
-	"fmt"
-
 	"github.com/valyala/fastjson"
 )
 
@@ -214,6 +211,9 @@ func gobDecodeUint(i *uint, data []byte) error {
 }
 
 func (l *Link) GobDecode(data []byte) error {
+	if len(data) == 0 {
+		return nil
+	}
 	mm := make(map[string][]byte)
 	g := gob.NewDecoder(bytes.NewReader(data))
 	if err := g.Decode(&mm); err != nil {
@@ -264,5 +264,5 @@ func (l *Link) GobDecode(data []byte) error {
 			return err
 		}
 	}
-	return errors.New(fmt.Sprintf("GobDecode is not implemented for %T", *l))
+	return nil
 }

natural_language_values_test.go

@@ -642,7 +642,7 @@ func TestLangRef_GobDecode(t *testing.T) {
 		{
 			name:    "some text",
 			l:       LangRef("ana are"),
-			data:    gobValue([]byte{'a', 'n', 'a', ' ', 'a', 'r', 'e'}),
+			data:    gobValue([]byte("ana are")),
 			wantErr: false,
 		},
 	}

object.go

@@ -130,7 +130,7 @@ func (a *ActivityVocabularyType) GobDecode(data []byte) error {
 		// NOTE(marius): this behaviour diverges from vanilla gob package
 		return nil
 	}
-	var bb string
+	var bb []byte
 	if err := gob.NewDecoder(bytes.NewReader(data)).Decode(&bb); err != nil {
 		return err
 	}
@@ -402,7 +402,7 @@ func (m *MimeType) GobDecode(data []byte) error {
 		// NOTE(marius): this behaviour diverges from vanilla gob package
 		return nil
 	}
-	var bb string
+	var bb []byte
 	if err := gob.NewDecoder(bytes.NewReader(data)).Decode(&bb); err != nil {
 		return err
 	}

object_test.go

@@ -377,7 +377,7 @@ func TestMimeType_GobDecode(t *testing.T) {
 		{
 			name:    "some mime-type",
 			m:       "application/json",
-			data:    gobValue("application/json"),
+			data:    gobValue([]byte("application/json")),
 			wantErr: false,
 		},
 	}
@@ -576,7 +576,7 @@ func TestActivityVocabularyType_GobDecode(t *testing.T) {
 		{
 			name:    "some activity type",
 			t:       PersonType,
-			data:    gobValue("Person"),
+			data:    gobValue([]byte("Person")),
 			wantErr: false,
 		},
 	}