object/id: Parse should belong to object format next

5 files changed, 68 insertions, 70 deletions

diff --git a/internal/testgit/object.go b/internal/testgit/object.go
index 5d2a38ec..a46ef02b 100644
--- a/internal/testgit/object.go
+++ b/internal/testgit/object.go
@@ -19,7 +19,7 @@ func (repo *Repo) HashObject(tb testing.TB, ty typ.Type, body io.Reader) id.Obje
 		tb.Fatalf("hash-object: %v", hex)
 	}
 
-	id, err := id.FromHex(repo.objectFormat, string(hex))
+	id, err := repo.objectFormat.FromString(string(hex))
 	if err != nil {
 		tb.Fatalf("parse git hash-object output %q: %v", hex, err)
 	}
diff --git a/object/commit/parse.go b/object/commit/parse.go
index 1212423f..1864055e 100644
--- a/object/commit/parse.go
+++ b/object/commit/parse.go
@@ -37,14 +37,14 @@ func Parse(body []byte, objectFormat id.ObjectFormat) (*Commit, error) {
 
 		switch string(key) {
 		case "tree":
-			id, err := id.FromHex(objectFormat, string(value))
+			id, err := objectFormat.FromString(string(value))
 			if err != nil {
 				return nil, fmt.Errorf("object: commit: tree: %w", err)
 			}
 
 			c.Tree = id
 		case "parent":
-			id, err := id.FromHex(objectFormat, string(value))
+			id, err := objectFormat.FromString(string(value))
 			if err != nil {
 				return nil, fmt.Errorf("object: commit: parent: %w", err)
 			}
diff --git a/object/id/object_format_ops.go b/object/id/object_format_ops.go
index 76077235..51bcae82 100644
--- a/object/id/object_format_ops.go
+++ b/object/id/object_format_ops.go
@@ -1,6 +1,10 @@
 package id
 
-import "hash"
+import (
+	"encoding/hex"
+	"fmt"
+	"hash"
+)
 
 // HexLen returns the encoded hexadecimal length.
 func (objectFormat ObjectFormat) HexLen() int {
@@ -22,6 +26,49 @@ func (objectFormat ObjectFormat) New() (hash.Hash, error) {
 	return newFn(), nil
 }
 
+// FromBytes builds an object ID from raw bytes for this object format.
+func (objectFormat ObjectFormat) FromBytes(b []byte) (ObjectID, error) {
+	var id ObjectID
+	if objectFormat.Size() == 0 {
+		return id, ErrInvalidObjectFormat
+	}
+
+	if len(b) != objectFormat.Size() {
+		return id, fmt.Errorf("%w: got %d bytes, expected %d", ErrInvalidObjectID, len(b), objectFormat.Size())
+	}
+
+	copy(id.data[:], b)
+	id.objectFormat = objectFormat
+
+	return id, nil
+}
+
+// FromString parses an object ID from its canonical hex representation.
+func (objectFormat ObjectFormat) FromString(s string) (ObjectID, error) {
+	var id ObjectID
+	if objectFormat.Size() == 0 {
+		return id, ErrInvalidObjectFormat
+	}
+
+	if len(s)&1 != 0 {
+		return id, fmt.Errorf("%w: odd hex length %d", ErrInvalidObjectID, len(s))
+	}
+
+	if len(s) != objectFormat.HexLen() {
+		return id, fmt.Errorf("%w: got %d chars, expected %d", ErrInvalidObjectID, len(s), objectFormat.HexLen())
+	}
+
+	decoded, err := hex.DecodeString(s)
+	if err != nil {
+		return id, fmt.Errorf("%w: decode: %w", ErrInvalidObjectID, err)
+	}
+
+	copy(id.data[:], decoded)
+	id.objectFormat = objectFormat
+
+	return id, nil
+}
+
 // String returns the canonical object format name.
 func (objectFormat ObjectFormat) String() string {
 	return objectFormat.details().name
diff --git a/object/id/object_id_parse.go b/object/id/object_id_parse.go
deleted file mode 100644
index 59b6669c..00000000
--- a/object/id/object_id_parse.go
+++ /dev/null
@@ -1,49 +0,0 @@
-package id
-
-import (
-	"encoding/hex"
-	"fmt"
-)
-
-// FromBytes builds an object ID from raw bytes for the specified object format.
-func FromBytes(objectFormat ObjectFormat, b []byte) (ObjectID, error) {
-	var id ObjectID
-	if objectFormat.Size() == 0 {
-		return id, ErrInvalidObjectFormat
-	}
-
-	if len(b) != objectFormat.Size() {
-		return id, fmt.Errorf("%w: got %d bytes, expected %d", ErrInvalidObjectID, len(b), objectFormat.Size())
-	}
-
-	copy(id.data[:], b)
-	id.objectFormat = objectFormat
-
-	return id, nil
-}
-
-// FromHex parses an object ID from hex for the specified object format.
-func FromHex(objectFormat ObjectFormat, s string) (ObjectID, error) {
-	var id ObjectID
-	if objectFormat.Size() == 0 {
-		return id, ErrInvalidObjectFormat
-	}
-
-	if len(s)%2 != 0 {
-		return id, fmt.Errorf("%w: odd hex length %d", ErrInvalidObjectID, len(s))
-	}
-
-	if len(s) != objectFormat.HexLen() {
-		return id, fmt.Errorf("%w: got %d chars, expected %d", ErrInvalidObjectID, len(s), objectFormat.HexLen())
-	}
-
-	decoded, err := hex.DecodeString(s)
-	if err != nil {
-		return id, fmt.Errorf("%w: decode: %w", ErrInvalidObjectID, err)
-	}
-
-	copy(id.data[:], decoded)
-	id.objectFormat = objectFormat
-
-	return id, nil
-}
diff --git a/object/id/object_id_test.go b/object/id/object_id_test.go
index 5d6130d2..40957692 100644
--- a/object/id/object_id_test.go
+++ b/object/id/object_id_test.go
@@ -11,13 +11,13 @@ import (
 func TestFromBytesErrors(t *testing.T) {
 	t.Parallel()
 
-	_, err := id.FromBytes(id.ObjectFormatUnknown, []byte{1, 2})
+	_, err := id.ObjectFormatUnknown.FromBytes([]byte{1, 2})
 	if err == nil {
 		t.Fatalf("expected FromBytes unknown object format error")
 	}
 
 	for _, objectFormat := range id.SupportedObjectFormats() {
-		_, err = id.FromBytes(objectFormat, []byte{1, 2})
+		_, err = objectFormat.FromBytes([]byte{1, 2})
 		if err == nil {
 			t.Fatalf("expected FromBytes wrong size error")
 		}
@@ -28,9 +28,9 @@ func TestBytesReturnsCopy(t *testing.T) {
 	t.Parallel()
 
 	for _, objectFormat := range id.SupportedObjectFormats() {
-		id, err := id.FromHex(objectFormat, strings.Repeat("01", objectFormat.Size()))
+		id, err := objectFormat.FromString(strings.Repeat("01", objectFormat.Size()))
 		if err != nil {
-			t.Fatalf("ParseHex failed: %v", err)
+			t.Fatalf("FromString failed: %v", err)
 		}
 
 		b1 := id.Bytes()
@@ -47,15 +47,15 @@ func TestBytesReturnsCopy(t *testing.T) {
 	}
 }
 
-func TestFromHexErrors(t *testing.T) {
+func TestFromStringErrors(t *testing.T) {
 	t.Parallel()
 
 	t.Run("unknown object format", func(t *testing.T) {
 		t.Parallel()
 
-		_, err := id.FromHex(id.ObjectFormatUnknown, "00")
+		_, err := id.ObjectFormatUnknown.FromString("00")
 		if err == nil {
-			t.Fatalf("expected FromHex error")
+			t.Fatalf("expected FromString error")
 		}
 	})
 	// TODO: This may need to be revisited when hash-function-transition is implemented.
@@ -64,25 +64,25 @@ func TestFromHexErrors(t *testing.T) {
 		t.Run(objectFormat.String(), func(t *testing.T) {
 			t.Parallel()
 
-			_, err := id.FromHex(objectFormat, strings.Repeat("0", objectFormat.HexLen()-1))
+			_, err := objectFormat.FromString(strings.Repeat("0", objectFormat.HexLen()-1))
 			if err == nil {
-				t.Fatalf("expected FromHex odd-len error")
+				t.Fatalf("expected FromString odd-len error")
 			}
 
-			_, err = id.FromHex(objectFormat, strings.Repeat("0", objectFormat.HexLen()-2))
+			_, err = objectFormat.FromString(strings.Repeat("0", objectFormat.HexLen()-2))
 			if err == nil {
-				t.Fatalf("expected FromHex wrong-len error")
+				t.Fatalf("expected FromString wrong-len error")
 			}
 
-			_, err = id.FromHex(objectFormat, "z"+strings.Repeat("0", objectFormat.HexLen()-1))
+			_, err = objectFormat.FromString("z" + strings.Repeat("0", objectFormat.HexLen()-1))
 			if err == nil {
-				t.Fatalf("expected FromHex invalid-hex error")
+				t.Fatalf("expected FromString invalid-hex error")
 			}
 		})
 	}
 }
 
-func TestFromHexRoundtrip(t *testing.T) {
+func TestFromStringRoundtrip(t *testing.T) {
 	t.Parallel()
 
 	for _, objectFormat := range id.SupportedObjectFormats() {
@@ -91,9 +91,9 @@ func TestFromHexRoundtrip(t *testing.T) {
 
 			hex := strings.Repeat("01", objectFormat.Size())
 
-			i, err := id.FromHex(objectFormat, hex)
+			i, err := objectFormat.FromString(hex)
 			if err != nil {
-				t.Fatalf("FromHex failed: %v", err)
+				t.Fatalf("FromString failed: %v", err)
 			}
 
 			if got := i.String(); got != hex {
@@ -109,7 +109,7 @@ func TestFromHexRoundtrip(t *testing.T) {
 				t.Fatalf("Bytes len = %d, want %d", len(raw), objectFormat.Size())
 			}
 
-			id2, err := id.FromBytes(objectFormat, raw)
+			id2, err := objectFormat.FromBytes(raw)
 			if err != nil {
 				t.Fatalf("FromBytes failed: %v", err)
 			}