Add parsing support for:

{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Resolves issue #24

2 files changed, 59 insertions, 12 deletions

diff --git a/uuid.go b/uuid.go
index 920dadf..524404c 100644
--- a/uuid.go
+++ b/uuid.go
@@ -1,4 +1,4 @@
-// Copyright 2016 Google Inc.  All rights reserved.
+// Copyright 2018 Google Inc.  All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
@@ -35,20 +35,43 @@ const (
 
 var rander = rand.Reader // random function
 
-// Parse decodes s into a UUID or returns an error.  Both the UUID form of
-// xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx and
-// urn:uuid:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx are decoded.
+// Parse decodes s into a UUID or returns an error.  Both the standard UUID
+// forms of xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx and
+// urn:uuid:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx are decoded as well as the
+// Microsoft encoding {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} and the raw hex
+// encoding: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx.
 func Parse(s string) (UUID, error) {
 	var uuid UUID
-	if len(s) != 36 {
-		if len(s) != 36+9 {
-			return uuid, fmt.Errorf("invalid UUID length: %d", len(s))
-		}
+	switch len(s) {
+	// xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
+	case 36:
+
+	// urn:uuid:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
+	case 36 + 9:
 		if strings.ToLower(s[:9]) != "urn:uuid:" {
 			return uuid, fmt.Errorf("invalid urn prefix: %q", s[:9])
 		}
 		s = s[9:]
+
+	// {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}
+	case 36 + 2:
+		s = s[1:]
+
+	// xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+	case 32:
+		var ok bool
+		for i := range uuid {
+			uuid[i], ok = xtob(s[i*2], s[i*2+1])
+			if !ok {
+				return uuid, errors.New("invalid UUID format")
+			}
+		}
+		return uuid, nil
+	default:
+		return uuid, fmt.Errorf("invalid UUID length: %d", len(s))
 	}
+	// s is now at least 36 bytes long
+	// it must be of the form  xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
 	if s[8] != '-' || s[13] != '-' || s[18] != '-' || s[23] != '-' {
 		return uuid, errors.New("invalid UUID format")
 	}
@@ -70,15 +93,29 @@ func Parse(s string) (UUID, error) {
 // ParseBytes is like Parse, except it parses a byte slice instead of a string.
 func ParseBytes(b []byte) (UUID, error) {
 	var uuid UUID
-	if len(b) != 36 {
-		if len(b) != 36+9 {
-			return uuid, fmt.Errorf("invalid UUID length: %d", len(b))
-		}
+	switch len(b) {
+	case 36: // xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
+	case 36 + 9: // urn:uuid:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
 		if !bytes.Equal(bytes.ToLower(b[:9]), []byte("urn:uuid:")) {
 			return uuid, fmt.Errorf("invalid urn prefix: %q", b[:9])
 		}
 		b = b[9:]
+	case 36 + 2: // {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}
+		b = b[1:]
+	case 32: // xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+		var ok bool
+		for i := 0; i < 32; i += 2 {
+			uuid[i/2], ok = xtob(b[i], b[i+1])
+			if !ok {
+				return uuid, errors.New("invalid UUID format")
+			}
+		}
+		return uuid, nil
+	default:
+		return uuid, fmt.Errorf("invalid UUID length: %d", len(b))
 	}
+	// s is now at least 36 bytes long
+	// it must be of the form  xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
 	if b[8] != '-' || b[13] != '-' || b[18] != '-' || b[23] != '-' {
 		return uuid, errors.New("invalid UUID format")
 	}
diff --git a/uuid_test.go b/uuid_test.go
index c0a89f4..e7876f1 100644
--- a/uuid_test.go
+++ b/uuid_test.go
@@ -59,12 +59,22 @@ var tests = []test{
 	{"f47ac10b-58cc-4372-e567-0e02b2c3d479", 4, Future, true},
 	{"f47ac10b-58cc-4372-f567-0e02b2c3d479", 4, Future, true},
 
+
 	{"f47ac10b158cc-5372-a567-0e02b2c3d479", 0, Invalid, false},
 	{"f47ac10b-58cc25372-a567-0e02b2c3d479", 0, Invalid, false},
 	{"f47ac10b-58cc-53723a567-0e02b2c3d479", 0, Invalid, false},
 	{"f47ac10b-58cc-5372-a56740e02b2c3d479", 0, Invalid, false},
 	{"f47ac10b-58cc-5372-a567-0e02-2c3d479", 0, Invalid, false},
 	{"g47ac10b-58cc-4372-a567-0e02b2c3d479", 0, Invalid, false},
+
+
+	{"{f47ac10b-58cc-0372-8567-0e02b2c3d479}", 0, RFC4122, true},
+	{"{f47ac10b-58cc-0372-8567-0e02b2c3d479", 0, Invalid, false},
+	{"f47ac10b-58cc-0372-8567-0e02b2c3d479}", 0, Invalid, false},
+
+	{"f47ac10b58cc037285670e02b2c3d479", 0, RFC4122, true},
+	{"f47ac10b58cc037285670e02b2c3d4790", 0, Invalid, false},
+	{"f47ac10b58cc037285670e02b2c3d47", 0, Invalid, false},
 }
 
 var constants = []struct {