1 files changed, 57 insertions, 0 deletions
diff --git a/object/tag_serialize.go b/object/tag_serialize.go
new file mode 100644
index 00000000..9600b81f
--- /dev/null
+++ b/object/tag_serialize.go
@@ -0,0 +1,57 @@
+package object
+
+import (
+	"bytes"
+	"fmt"
+)
+
+func (tag *Tag) serialize() ([]byte, error) {
+	if tag.Target.Size() == 0 {
+		return nil, ErrInvalidObject
+	}
+
+	var buf bytes.Buffer
+	fmt.Fprintf(&buf, "object %s\n", tag.Target.String())
+
+	tyName, err := typeName(tag.TargetType)
+	if err != nil {
+		return nil, fmt.Errorf("object: tag: invalid target type %d", tag.TargetType)
+	}
+	buf.WriteString("type ")
+	buf.WriteString(tyName)
+	buf.WriteByte('\n')
+
+	buf.WriteString("tag ")
+	buf.Write(tag.Name)
+	buf.WriteByte('\n')
+
+	if tag.Tagger != nil {
+		taggerBytes, err := tag.Tagger.Serialize()
+		if err != nil {
+			return nil, err
+		}
+		buf.WriteString("tagger ")
+		buf.Write(taggerBytes)
+		buf.WriteByte('\n')
+	}
+
+	buf.WriteByte('\n')
+	buf.Write(tag.Message)
+	return buf.Bytes(), nil
+}
+
+// Serialize renders the raw object (header + body).
+func (tag *Tag) Serialize() ([]byte, error) {
+	body, err := tag.serialize()
+	if err != nil {
+		return nil, err
+	}
+	header, err := headerForType(TypeTag, body)
+	if err != nil {
+		return nil, err
+	}
+	raw := make([]byte, len(header)+len(body))
+	copy(raw, header)
+	copy(raw[len(header):], body)
+	return raw, nil
+}