From 13edf70fc959bdc2ecf68bb2da0a6cf358f016ce Mon Sep 17 00:00:00 2001
From: Ben Ramsey <ben@benramsey.com>
Date: Fri, 1 Apr 2022 16:08:22 -0500
Subject: [PATCH] feat: introduce Variant enum and use instead of constants

---
 composer.json                      |  2 +-
 src/BinaryUtils.php                | 12 ++--
 src/Guid/Fields.php                |  4 +-
 src/Rfc4122/Fields.php             |  3 +-
 src/Rfc4122/FieldsInterface.php    |  3 +-
 src/Rfc4122/VariantTrait.php       | 23 +++----
 src/Uuid.php                       | 28 ---------
 src/Variant.php                    | 36 +++++++++++
 tests/BinaryUtilsTest.php          | 29 +++++++--
 tests/ExpectedBehaviorTest.php     | 18 ++----
 tests/Guid/FieldsTest.php          | 11 ++--
 tests/Nonstandard/FieldsTest.php   |  4 +-
 tests/Rfc4122/FieldsTest.php       | 15 ++---
 tests/Rfc4122/VariantTraitTest.php |  3 +-
 tests/UuidTest.php                 | 99 +++++++++++++++---------------
 15 files changed, 157 insertions(+), 133 deletions(-)
 create mode 100644 src/Variant.php

diff --git a/composer.json b/composer.json
index 3da822e..7e4fec6 100644
--- a/composer.json
+++ b/composer.json
@@ -9,7 +9,7 @@
         "guid"
     ],
     "require": {
-        "php": "^8.0",
+        "php": "^8.1",
         "ext-ctype": "*",
         "ext-json": "*",
         "brick/math": "^0.8 || ^0.9"
diff --git a/src/BinaryUtils.php b/src/BinaryUtils.php
index fb8ba9a..8283f49 100644
--- a/src/BinaryUtils.php
+++ b/src/BinaryUtils.php
@@ -31,12 +31,14 @@ class BinaryUtils
      *
      * @psalm-pure
      */
-    public static function applyVariant(int $clockSeq): int
+    public static function applyVariant(int $clockSeq, Variant $variant = Variant::Rfc4122): int
     {
-        $clockSeq = $clockSeq & 0x3fff;
-        $clockSeq |= 0x8000;
-
-        return $clockSeq;
+        return match ($variant) {
+            Variant::ReservedNcs => $clockSeq & 0x7fff,
+            Variant::Rfc4122 => $clockSeq & 0x3fff | 0x8000,
+            Variant::ReservedMicrosoft => $clockSeq & 0x1fff | 0xc000,
+            Variant::ReservedFuture => $clockSeq & 0x1fff | 0xe000,
+        };
     }
 
     /**
diff --git a/src/Guid/Fields.php b/src/Guid/Fields.php
index d8a1a2b..eda6e6a 100644
--- a/src/Guid/Fields.php
+++ b/src/Guid/Fields.php
@@ -21,7 +21,7 @@ use Ramsey\Uuid\Rfc4122\NilTrait;
 use Ramsey\Uuid\Rfc4122\VariantTrait;
 use Ramsey\Uuid\Rfc4122\VersionTrait;
 use Ramsey\Uuid\Type\Hexadecimal;
-use Ramsey\Uuid\Uuid;
+use Ramsey\Uuid\Variant;
 
 use function bin2hex;
 use function dechex;
@@ -189,6 +189,6 @@ final class Fields implements FieldsInterface
 
         $variant = $this->getVariant();
 
-        return $variant === Uuid::RFC_4122 || $variant === Uuid::RESERVED_MICROSOFT;
+        return $variant === Variant::Rfc4122 || $variant === Variant::ReservedMicrosoft;
     }
 }
diff --git a/src/Rfc4122/Fields.php b/src/Rfc4122/Fields.php
index 2ccc20b..0c54a11 100644
--- a/src/Rfc4122/Fields.php
+++ b/src/Rfc4122/Fields.php
@@ -18,6 +18,7 @@ use Ramsey\Uuid\Exception\InvalidArgumentException;
 use Ramsey\Uuid\Fields\SerializableFieldsTrait;
 use Ramsey\Uuid\Type\Hexadecimal;
 use Ramsey\Uuid\Uuid;
+use Ramsey\Uuid\Variant;
 
 use function bin2hex;
 use function dechex;
@@ -189,6 +190,6 @@ final class Fields implements FieldsInterface
             return true;
         }
 
-        return $this->getVariant() === Uuid::RFC_4122;
+        return $this->getVariant() === Variant::Rfc4122;
     }
 }
diff --git a/src/Rfc4122/FieldsInterface.php b/src/Rfc4122/FieldsInterface.php
index a303525..5b4b801 100644
--- a/src/Rfc4122/FieldsInterface.php
+++ b/src/Rfc4122/FieldsInterface.php
@@ -16,6 +16,7 @@ namespace Ramsey\Uuid\Rfc4122;
 
 use Ramsey\Uuid\Fields\FieldsInterface as BaseFieldsInterface;
 use Ramsey\Uuid\Type\Hexadecimal;
+use Ramsey\Uuid\Variant;
 
 /**
  * RFC 4122 defines fields for a specific variant of UUID
@@ -95,7 +96,7 @@ interface FieldsInterface extends BaseFieldsInterface
      *
      * @link http://tools.ietf.org/html/rfc4122#section-4.1.1 RFC 4122, § 4.1.1: Variant
      */
-    public function getVariant(): int;
+    public function getVariant(): Variant;
 
     /**
      * Returns the version
diff --git a/src/Rfc4122/VariantTrait.php b/src/Rfc4122/VariantTrait.php
index 4c98165..81c0d0d 100644
--- a/src/Rfc4122/VariantTrait.php
+++ b/src/Rfc4122/VariantTrait.php
@@ -15,7 +15,7 @@ declare(strict_types=1);
 namespace Ramsey\Uuid\Rfc4122;
 
 use Ramsey\Uuid\Exception\InvalidBytesException;
-use Ramsey\Uuid\Uuid;
+use Ramsey\Uuid\Variant;
 
 use function decbin;
 use function str_pad;
@@ -41,18 +41,11 @@ trait VariantTrait
     /**
      * Returns the variant identifier, according to RFC 4122, for the given bytes
      *
-     * The following values may be returned:
-     *
-     * - `0` -- Reserved, NCS backward compatibility.
-     * - `2` -- The variant specified in RFC 4122.
-     * - `6` -- Reserved, Microsoft Corporation backward compatibility.
-     * - `7` -- Reserved for future definition.
-     *
      * @link https://tools.ietf.org/html/rfc4122#section-4.1.1 RFC 4122, § 4.1.1: Variant
      *
-     * @return int The variant identifier, according to RFC 4122
+     * @return Variant The variant identifier, according to RFC 4122
      */
-    public function getVariant(): int
+    public function getVariant(): Variant
     {
         if (strlen($this->getBytes()) !== 16) {
             throw new InvalidBytesException('Invalid number of bytes');
@@ -76,13 +69,13 @@ trait VariantTrait
         $msb = substr($binary, 0, 3);
 
         if ($msb === '111') {
-            $variant = Uuid::RESERVED_FUTURE;
+            $variant = Variant::ReservedFuture;
         } elseif ($msb === '110') {
-            $variant = Uuid::RESERVED_MICROSOFT;
-        } elseif (strpos($msb, '10') === 0) {
-            $variant = Uuid::RFC_4122;
+            $variant = Variant::ReservedMicrosoft;
+        } elseif (str_starts_with($msb, '10')) {
+            $variant = Variant::Rfc4122;
         } else {
-            $variant = Uuid::RESERVED_NCS;
+            $variant = Variant::ReservedNcs;
         }
 
         return $variant;
diff --git a/src/Uuid.php b/src/Uuid.php
index bf9048a..5f6e02e 100644
--- a/src/Uuid.php
+++ b/src/Uuid.php
@@ -80,34 +80,6 @@ class Uuid implements Rfc4122UuidInterface
      */
     public const NIL = '00000000-0000-0000-0000-000000000000';
 
-    /**
-     * Variant: reserved, NCS backward compatibility
-     *
-     * @link http://tools.ietf.org/html/rfc4122#section-4.1.1 RFC 4122, § 4.1.1: Variant
-     */
-    public const RESERVED_NCS = 0;
-
-    /**
-     * Variant: the UUID layout specified in RFC 4122
-     *
-     * @link http://tools.ietf.org/html/rfc4122#section-4.1.1 RFC 4122, § 4.1.1: Variant
-     */
-    public const RFC_4122 = 2;
-
-    /**
-     * Variant: reserved, Microsoft Corporation backward compatibility
-     *
-     * @link http://tools.ietf.org/html/rfc4122#section-4.1.1 RFC 4122, § 4.1.1: Variant
-     */
-    public const RESERVED_MICROSOFT = 6;
-
-    /**
-     * Variant: reserved for future definition
-     *
-     * @link http://tools.ietf.org/html/rfc4122#section-4.1.1 RFC 4122, § 4.1.1: Variant
-     */
-    public const RESERVED_FUTURE = 7;
-
     /**
      * @deprecated Use {@see ValidatorInterface::getPattern()} instead.
      */
diff --git a/src/Variant.php b/src/Variant.php
new file mode 100644
index 0000000..5b7505c
--- /dev/null
+++ b/src/Variant.php
@@ -0,0 +1,36 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Ramsey\Uuid;
+
+enum Variant: int
+{
+    /**
+     * Variant: reserved, NCS backward compatibility
+     *
+     * @link http://tools.ietf.org/html/rfc4122#section-4.1.1 RFC 4122, § 4.1.1: Variant
+     */
+    case ReservedNcs = 0;
+
+    /**
+     * Variant: the UUID layout specified in RFC 4122
+     *
+     * @link http://tools.ietf.org/html/rfc4122#section-4.1.1 RFC 4122, § 4.1.1: Variant
+     */
+    case Rfc4122 = 2;
+
+    /**
+     * Variant: reserved, Microsoft Corporation backward compatibility
+     *
+     * @link http://tools.ietf.org/html/rfc4122#section-4.1.1 RFC 4122, § 4.1.1: Variant
+     */
+    case ReservedMicrosoft = 6;
+
+    /**
+     * Variant: reserved for future definition
+     *
+     * @link http://tools.ietf.org/html/rfc4122#section-4.1.1 RFC 4122, § 4.1.1: Variant
+     */
+    case ReservedFuture = 7;
+}
diff --git a/tests/BinaryUtilsTest.php b/tests/BinaryUtilsTest.php
index 0497bfd..0a4ec16 100644
--- a/tests/BinaryUtilsTest.php
+++ b/tests/BinaryUtilsTest.php
@@ -5,6 +5,7 @@ declare(strict_types=1);
 namespace Ramsey\Uuid\Test;
 
 use Ramsey\Uuid\BinaryUtils;
+use Ramsey\Uuid\Variant;
 
 use function dechex;
 
@@ -22,10 +23,10 @@ class BinaryUtilsTest extends TestCase
     /**
      * @dataProvider provideVariantTestValues
      */
-    public function testApplyVariant(int $clockSeq, int $expectedInt, string $expectedHex): void
+    public function testApplyVariant(int $clockSeq, Variant $variant, int $expectedInt, string $expectedHex): void
     {
-        $this->assertSame($expectedInt, BinaryUtils::applyVariant($clockSeq));
-        $this->assertSame($expectedHex, dechex(BinaryUtils::applyVariant($clockSeq)));
+        $this->assertSame($expectedInt, BinaryUtils::applyVariant($clockSeq, $variant));
+        $this->assertSame($expectedHex, dechex(BinaryUtils::applyVariant($clockSeq, $variant)));
     }
 
     /**
@@ -128,108 +129,128 @@ class BinaryUtilsTest extends TestCase
     }
 
     /**
-     * @phpcsSuppress SlevomatCodingStandard.TypeHints.ReturnTypeHint.MissingTraversableTypeHintSpecification
+     * @return array<array{clockSeq: int, variant: Variant, expectedInt: int, expectedHex: string}>
      */
     public function provideVariantTestValues(): array
     {
         return [
             [
                 'clockSeq' => 0,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 32768,
                 'expectedHex' => '8000',
             ],
             [
                 'clockSeq' => 4096,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 36864,
                 'expectedHex' => '9000',
             ],
             [
                 'clockSeq' => 8192,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 40960,
                 'expectedHex' => 'a000',
             ],
             [
                 'clockSeq' => 12288,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 45056,
                 'expectedHex' => 'b000',
             ],
             [
                 'clockSeq' => 4095,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 36863,
                 'expectedHex' => '8fff',
             ],
             [
                 'clockSeq' => 8191,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 40959,
                 'expectedHex' => '9fff',
             ],
             [
                 'clockSeq' => 12287,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 45055,
                 'expectedHex' => 'afff',
             ],
             [
                 'clockSeq' => 16383,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 49151,
                 'expectedHex' => 'bfff',
             ],
             [
                 'clockSeq' => 16384,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 32768,
                 'expectedHex' => '8000',
             ],
             [
                 'clockSeq' => 20480,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 36864,
                 'expectedHex' => '9000',
             ],
             [
                 'clockSeq' => 24576,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 40960,
                 'expectedHex' => 'a000',
             ],
             [
                 'clockSeq' => 28672,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 45056,
                 'expectedHex' => 'b000',
             ],
             [
                 'clockSeq' => 32768,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 32768,
                 'expectedHex' => '8000',
             ],
             [
                 'clockSeq' => 36864,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 36864,
                 'expectedHex' => '9000',
             ],
             [
                 'clockSeq' => 40960,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 40960,
                 'expectedHex' => 'a000',
             ],
             [
                 'clockSeq' => 45056,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 45056,
                 'expectedHex' => 'b000',
             ],
             [
                 'clockSeq' => 36863,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 36863,
                 'expectedHex' => '8fff',
             ],
             [
                 'clockSeq' => 40959,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 40959,
                 'expectedHex' => '9fff',
             ],
             [
                 'clockSeq' => 45055,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 45055,
                 'expectedHex' => 'afff',
             ],
             [
                 'clockSeq' => 49151,
+                'variant' => Variant::Rfc4122,
                 'expectedInt' => 49151,
                 'expectedHex' => 'bfff',
             ],
diff --git a/tests/ExpectedBehaviorTest.php b/tests/ExpectedBehaviorTest.php
index 592a288..8cbe2a3 100644
--- a/tests/ExpectedBehaviorTest.php
+++ b/tests/ExpectedBehaviorTest.php
@@ -2,18 +2,16 @@
 
 namespace Ramsey\Uuid\Test;
 
-use Ramsey\Uuid\Codec\CodecInterface;
 use Ramsey\Uuid\Codec\TimestampFirstCombCodec;
-use Ramsey\Uuid\Converter\TimeConverterInterface;
 use Ramsey\Uuid\Generator\CombGenerator;
 use Ramsey\Uuid\Generator\DefaultTimeGenerator;
-use Ramsey\Uuid\Math\BrickMathCalculator;
 use Ramsey\Uuid\Rfc4122\UuidInterface;
 use Ramsey\Uuid\Rfc4122\UuidV1;
 use Ramsey\Uuid\Type\Hexadecimal;
 use Ramsey\Uuid\Type\Time;
 use Ramsey\Uuid\Uuid;
 use Ramsey\Uuid\UuidFactory;
+use Ramsey\Uuid\Variant;
 use stdClass;
 
 /**
@@ -81,7 +79,7 @@ class ExpectedBehaviorTest extends TestCase
             . $uuid->getFields()->getNode()->toString()
         );
 
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame((int) substr($method, -1), $uuid->getFields()->getVersion());
         $this->assertTrue(ctype_digit((string) $uuid->getInteger()));
     }
@@ -204,7 +202,7 @@ class ExpectedBehaviorTest extends TestCase
         $this->assertInstanceOf('Ramsey\Uuid\UuidInterface', $uuid);
         $this->assertSame($string, $uuid->toString());
         $this->assertSame($version, $uuid->getFields()->getVersion());
-        $this->assertSame($variant, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::from($variant), $uuid->getFields()->getVariant());
 
         $components = explode('-', $string);
 
@@ -234,7 +232,7 @@ class ExpectedBehaviorTest extends TestCase
         $this->assertInstanceOf('Ramsey\Uuid\UuidInterface', $uuid);
         $this->assertSame($string, $uuid->toString());
         $this->assertSame($version, $uuid->getFields()->getVersion());
-        $this->assertSame($variant, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::from($variant), $uuid->getFields()->getVariant());
 
         $components = explode('-', $string);
 
@@ -264,7 +262,7 @@ class ExpectedBehaviorTest extends TestCase
         $this->assertInstanceOf('Ramsey\Uuid\UuidInterface', $uuid);
         $this->assertSame($string, $uuid->toString());
         $this->assertSame($version, $uuid->getFields()->getVersion());
-        $this->assertSame($variant, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::from($variant), $uuid->getFields()->getVariant());
 
         $components = explode('-', $string);
 
@@ -540,7 +538,7 @@ class ExpectedBehaviorTest extends TestCase
         $expectedBytes = hex2bin($expectedHex);
 
         $this->assertInstanceOf('Ramsey\Uuid\UuidInterface', $uuid);
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(4, $uuid->getFields()->getVersion());
         $this->assertSame($expectedBytes, $uuid->getBytes());
         $this->assertSame($expectedHex, (string) $uuid->getHex());
@@ -562,10 +560,6 @@ class ExpectedBehaviorTest extends TestCase
             ['NAMESPACE_OID', '6ba7b812-9dad-11d1-80b4-00c04fd430c8'],
             ['NAMESPACE_X500', '6ba7b814-9dad-11d1-80b4-00c04fd430c8'],
             ['NIL', '00000000-0000-0000-0000-000000000000'],
-            ['RESERVED_NCS', 0],
-            ['RFC_4122', 2],
-            ['RESERVED_MICROSOFT', 6],
-            ['RESERVED_FUTURE', 7],
             ['VALID_PATTERN', '^[0-9A-Fa-f]{8}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{12}$'],
             ['UUID_TYPE_TIME', 1],
             ['UUID_TYPE_IDENTIFIER', 2],
diff --git a/tests/Guid/FieldsTest.php b/tests/Guid/FieldsTest.php
index 4924e55..38616a0 100644
--- a/tests/Guid/FieldsTest.php
+++ b/tests/Guid/FieldsTest.php
@@ -8,6 +8,7 @@ use Ramsey\Uuid\Exception\InvalidArgumentException;
 use Ramsey\Uuid\Guid\Fields;
 use Ramsey\Uuid\Test\TestCase;
 use Ramsey\Uuid\Type\Hexadecimal;
+use Ramsey\Uuid\Variant;
 
 use function hex2bin;
 use function serialize;
@@ -132,7 +133,7 @@ class FieldsTest extends TestCase
             ['b08c6fff7dc5e111cb210800200c9a66', 'getTimeLow', 'ff6f8cb0'],
             ['b08c6fff7dc5e111cb210800200c9a66', 'getTimeMid', 'c57d'],
             ['b08c6fff7dc5e111cb210800200c9a66', 'getTimestamp', '1e1c57dff6f8cb0'],
-            ['b08c6fff7dc5e111cb210800200c9a66', 'getVariant', 6],
+            ['b08c6fff7dc5e111cb210800200c9a66', 'getVariant', Variant::ReservedMicrosoft],
             ['b08c6fff7dc5e111cb210800200c9a66', 'getVersion', 1],
             ['b08c6fff7dc5e111cb210800200c9a66', 'isNil', false],
 
@@ -145,7 +146,7 @@ class FieldsTest extends TestCase
             ['b08c6fff7dc5e141db210800200c9a66', 'getTimeLow', 'ff6f8cb0'],
             ['b08c6fff7dc5e141db210800200c9a66', 'getTimeMid', 'c57d'],
             ['b08c6fff7dc5e141db210800200c9a66', 'getTimestamp', '1e1c57dff6f8cb0'],
-            ['b08c6fff7dc5e141db210800200c9a66', 'getVariant', 6],
+            ['b08c6fff7dc5e141db210800200c9a66', 'getVariant', Variant::ReservedMicrosoft],
             ['b08c6fff7dc5e141db210800200c9a66', 'getVersion', 4],
             ['b08c6fff7dc5e141db210800200c9a66', 'isNil', false],
 
@@ -158,7 +159,7 @@ class FieldsTest extends TestCase
             ['b08c6fff7dc5e1318b210800200c9a66', 'getTimeLow', 'ff6f8cb0'],
             ['b08c6fff7dc5e1318b210800200c9a66', 'getTimeMid', 'c57d'],
             ['b08c6fff7dc5e1318b210800200c9a66', 'getTimestamp', '1e1c57dff6f8cb0'],
-            ['b08c6fff7dc5e1318b210800200c9a66', 'getVariant', 2],
+            ['b08c6fff7dc5e1318b210800200c9a66', 'getVariant', Variant::Rfc4122],
             ['b08c6fff7dc5e1318b210800200c9a66', 'getVersion', 3],
             ['b08c6fff7dc5e1318b210800200c9a66', 'isNil', false],
 
@@ -171,7 +172,7 @@ class FieldsTest extends TestCase
             ['b08c6fff7dc5e1519b210800200c9a66', 'getTimeLow', 'ff6f8cb0'],
             ['b08c6fff7dc5e1519b210800200c9a66', 'getTimeMid', 'c57d'],
             ['b08c6fff7dc5e1519b210800200c9a66', 'getTimestamp', '1e1c57dff6f8cb0'],
-            ['b08c6fff7dc5e1519b210800200c9a66', 'getVariant', 2],
+            ['b08c6fff7dc5e1519b210800200c9a66', 'getVariant', Variant::Rfc4122],
             ['b08c6fff7dc5e1519b210800200c9a66', 'getVersion', 5],
             ['b08c6fff7dc5e1519b210800200c9a66', 'isNil', false],
 
@@ -184,7 +185,7 @@ class FieldsTest extends TestCase
             ['00000000000000000000000000000000', 'getTimeLow', '00000000'],
             ['00000000000000000000000000000000', 'getTimeMid', '0000'],
             ['00000000000000000000000000000000', 'getTimestamp', '000000000000000'],
-            ['00000000000000000000000000000000', 'getVariant', 0],
+            ['00000000000000000000000000000000', 'getVariant', Variant::ReservedNcs],
             ['00000000000000000000000000000000', 'getVersion', null],
             ['00000000000000000000000000000000', 'isNil', true],
         ];
diff --git a/tests/Nonstandard/FieldsTest.php b/tests/Nonstandard/FieldsTest.php
index 319896a..f5ea533 100644
--- a/tests/Nonstandard/FieldsTest.php
+++ b/tests/Nonstandard/FieldsTest.php
@@ -8,7 +8,7 @@ use Ramsey\Uuid\Exception\InvalidArgumentException;
 use Ramsey\Uuid\Nonstandard\Fields;
 use Ramsey\Uuid\Test\TestCase;
 use Ramsey\Uuid\Type\Hexadecimal;
-use Ramsey\Uuid\Uuid;
+use Ramsey\Uuid\Variant;
 
 use function hex2bin;
 use function serialize;
@@ -60,7 +60,7 @@ class FieldsTest extends TestCase
             ['ff6f8cb0-c57d-91e1-0b21-0800200c9a66', 'getTimeLow', 'ff6f8cb0'],
             ['ff6f8cb0-c57d-91e1-0b21-0800200c9a66', 'getTimeMid', 'c57d'],
             ['ff6f8cb0-c57d-91e1-0b21-0800200c9a66', 'getTimestamp', '1e1c57dff6f8cb0'],
-            ['ff6f8cb0-c57d-91e1-0b21-0800200c9a66', 'getVariant', Uuid::RESERVED_NCS],
+            ['ff6f8cb0-c57d-91e1-0b21-0800200c9a66', 'getVariant', Variant::ReservedNcs],
             ['ff6f8cb0-c57d-91e1-0b21-0800200c9a66', 'getVersion', null],
             ['ff6f8cb0-c57d-91e1-0b21-0800200c9a66', 'isNil', false],
         ];
diff --git a/tests/Rfc4122/FieldsTest.php b/tests/Rfc4122/FieldsTest.php
index eb84dee..aefa149 100644
--- a/tests/Rfc4122/FieldsTest.php
+++ b/tests/Rfc4122/FieldsTest.php
@@ -8,6 +8,7 @@ use Ramsey\Uuid\Exception\InvalidArgumentException;
 use Ramsey\Uuid\Rfc4122\Fields;
 use Ramsey\Uuid\Test\TestCase;
 use Ramsey\Uuid\Type\Hexadecimal;
+use Ramsey\Uuid\Variant;
 
 use function hex2bin;
 use function serialize;
@@ -123,7 +124,7 @@ class FieldsTest extends TestCase
             ['ff6f8cb0-c57d-11e1-9b21-0800200c9a66', 'getTimeLow', 'ff6f8cb0'],
             ['ff6f8cb0-c57d-11e1-9b21-0800200c9a66', 'getTimeMid', 'c57d'],
             ['ff6f8cb0-c57d-11e1-9b21-0800200c9a66', 'getTimestamp', '1e1c57dff6f8cb0'],
-            ['ff6f8cb0-c57d-11e1-9b21-0800200c9a66', 'getVariant', 2],
+            ['ff6f8cb0-c57d-11e1-9b21-0800200c9a66', 'getVariant', Variant::Rfc4122],
             ['ff6f8cb0-c57d-11e1-9b21-0800200c9a66', 'getVersion', 1],
             ['ff6f8cb0-c57d-11e1-9b21-0800200c9a66', 'isNil', false],
 
@@ -135,7 +136,7 @@ class FieldsTest extends TestCase
             ['ff6f8cb0-c57d-41e1-ab21-0800200c9a66', 'getTimeLow', 'ff6f8cb0'],
             ['ff6f8cb0-c57d-41e1-ab21-0800200c9a66', 'getTimeMid', 'c57d'],
             ['ff6f8cb0-c57d-41e1-ab21-0800200c9a66', 'getTimestamp', '1e1c57dff6f8cb0'],
-            ['ff6f8cb0-c57d-41e1-ab21-0800200c9a66', 'getVariant', 2],
+            ['ff6f8cb0-c57d-41e1-ab21-0800200c9a66', 'getVariant', Variant::Rfc4122],
             ['ff6f8cb0-c57d-41e1-ab21-0800200c9a66', 'getVersion', 4],
             ['ff6f8cb0-c57d-41e1-ab21-0800200c9a66', 'isNil', false],
 
@@ -147,7 +148,7 @@ class FieldsTest extends TestCase
             ['ff6f8cb0-c57d-31e1-bb21-0800200c9a66', 'getTimeLow', 'ff6f8cb0'],
             ['ff6f8cb0-c57d-31e1-bb21-0800200c9a66', 'getTimeMid', 'c57d'],
             ['ff6f8cb0-c57d-31e1-bb21-0800200c9a66', 'getTimestamp', '1e1c57dff6f8cb0'],
-            ['ff6f8cb0-c57d-31e1-bb21-0800200c9a66', 'getVariant', 2],
+            ['ff6f8cb0-c57d-31e1-bb21-0800200c9a66', 'getVariant', Variant::Rfc4122],
             ['ff6f8cb0-c57d-31e1-bb21-0800200c9a66', 'getVersion', 3],
             ['ff6f8cb0-c57d-31e1-bb21-0800200c9a66', 'isNil', false],
 
@@ -159,7 +160,7 @@ class FieldsTest extends TestCase
             ['ff6f8cb0-c57d-51e1-8b21-0800200c9a66', 'getTimeLow', 'ff6f8cb0'],
             ['ff6f8cb0-c57d-51e1-8b21-0800200c9a66', 'getTimeMid', 'c57d'],
             ['ff6f8cb0-c57d-51e1-8b21-0800200c9a66', 'getTimestamp', '1e1c57dff6f8cb0'],
-            ['ff6f8cb0-c57d-51e1-8b21-0800200c9a66', 'getVariant', 2],
+            ['ff6f8cb0-c57d-51e1-8b21-0800200c9a66', 'getVariant', Variant::Rfc4122],
             ['ff6f8cb0-c57d-51e1-8b21-0800200c9a66', 'getVersion', 5],
             ['ff6f8cb0-c57d-51e1-8b21-0800200c9a66', 'isNil', false],
 
@@ -171,7 +172,7 @@ class FieldsTest extends TestCase
             ['ff6f8cb0-c57d-61e1-8b21-0800200c9a66', 'getTimeLow', 'ff6f8cb0'],
             ['ff6f8cb0-c57d-61e1-8b21-0800200c9a66', 'getTimeMid', 'c57d'],
             ['ff6f8cb0-c57d-61e1-8b21-0800200c9a66', 'getTimestamp', 'ff6f8cb0c57d1e1'],
-            ['ff6f8cb0-c57d-61e1-8b21-0800200c9a66', 'getVariant', 2],
+            ['ff6f8cb0-c57d-61e1-8b21-0800200c9a66', 'getVariant', Variant::Rfc4122],
             ['ff6f8cb0-c57d-61e1-8b21-0800200c9a66', 'getVersion', 6],
             ['ff6f8cb0-c57d-61e1-8b21-0800200c9a66', 'isNil', false],
 
@@ -183,7 +184,7 @@ class FieldsTest extends TestCase
             ['00000000-0000-0000-0000-000000000000', 'getTimeLow', '00000000'],
             ['00000000-0000-0000-0000-000000000000', 'getTimeMid', '0000'],
             ['00000000-0000-0000-0000-000000000000', 'getTimestamp', '000000000000000'],
-            ['00000000-0000-0000-0000-000000000000', 'getVariant', 0],
+            ['00000000-0000-0000-0000-000000000000', 'getVariant', Variant::ReservedNcs],
             ['00000000-0000-0000-0000-000000000000', 'getVersion', null],
             ['00000000-0000-0000-0000-000000000000', 'isNil', true],
 
@@ -195,7 +196,7 @@ class FieldsTest extends TestCase
             ['000001f5-5cde-21ea-8400-0242ac130003', 'getTimeLow', '000001f5'],
             ['000001f5-5cde-21ea-8400-0242ac130003', 'getTimeMid', '5cde'],
             ['000001f5-5cde-21ea-8400-0242ac130003', 'getTimestamp', '1ea5cde00000000'],
-            ['000001f5-5cde-21ea-8400-0242ac130003', 'getVariant', 2],
+            ['000001f5-5cde-21ea-8400-0242ac130003', 'getVariant', Variant::Rfc4122],
             ['000001f5-5cde-21ea-8400-0242ac130003', 'getVersion', 2],
             ['000001f5-5cde-21ea-8400-0242ac130003', 'isNil', false],
         ];
diff --git a/tests/Rfc4122/VariantTraitTest.php b/tests/Rfc4122/VariantTraitTest.php
index c0e2593..17251d2 100644
--- a/tests/Rfc4122/VariantTraitTest.php
+++ b/tests/Rfc4122/VariantTraitTest.php
@@ -9,6 +9,7 @@ use Ramsey\Uuid\Exception\InvalidBytesException;
 use Ramsey\Uuid\Rfc4122\Fields;
 use Ramsey\Uuid\Rfc4122\VariantTrait;
 use Ramsey\Uuid\Test\TestCase;
+use Ramsey\Uuid\Variant;
 
 use function hex2bin;
 use function str_replace;
@@ -54,7 +55,7 @@ class VariantTraitTest extends TestCase
             'getBytes' => $bytes,
         ]);
 
-        $this->assertSame($expectedVariant, $trait->getVariant());
+        $this->assertSame(Variant::from($expectedVariant), $trait->getVariant());
     }
 
     /**
diff --git a/tests/UuidTest.php b/tests/UuidTest.php
index 2ca65e6..05fee01 100644
--- a/tests/UuidTest.php
+++ b/tests/UuidTest.php
@@ -31,6 +31,7 @@ use Ramsey\Uuid\UuidFactory;
 use Ramsey\Uuid\UuidInterface;
 use Ramsey\Uuid\Validator\GenericValidator;
 use Ramsey\Uuid\Validator\ValidatorInterface;
+use Ramsey\Uuid\Variant;
 use stdClass;
 
 use function base64_decode;
@@ -344,7 +345,7 @@ class UuidTest extends TestCase
      *
      * @dataProvider provideVariousVariantUuids
      */
-    public function testGetVariantForVariousVariantUuids(string $uuid, int $variant): void
+    public function testGetVariantForVariousVariantUuids(string $uuid, Variant $variant): void
     {
         /** @var \Ramsey\Uuid\Rfc4122\UuidInterface $uuidInstance */
         $uuidInstance = Uuid::fromString($uuid);
@@ -357,22 +358,22 @@ class UuidTest extends TestCase
     public function provideVariousVariantUuids(): array
     {
         return [
-            ['ff6f8cb0-c57d-11e1-0b21-0800200c9a66', Uuid::RESERVED_NCS],
-            ['ff6f8cb0-c57d-11e1-1b21-0800200c9a66', Uuid::RESERVED_NCS],
-            ['ff6f8cb0-c57d-11e1-2b21-0800200c9a66', Uuid::RESERVED_NCS],
-            ['ff6f8cb0-c57d-11e1-3b21-0800200c9a66', Uuid::RESERVED_NCS],
-            ['ff6f8cb0-c57d-11e1-4b21-0800200c9a66', Uuid::RESERVED_NCS],
-            ['ff6f8cb0-c57d-11e1-5b21-0800200c9a66', Uuid::RESERVED_NCS],
-            ['ff6f8cb0-c57d-11e1-6b21-0800200c9a66', Uuid::RESERVED_NCS],
-            ['ff6f8cb0-c57d-11e1-7b21-0800200c9a66', Uuid::RESERVED_NCS],
-            ['ff6f8cb0-c57d-11e1-8b21-0800200c9a66', Uuid::RFC_4122],
-            ['ff6f8cb0-c57d-11e1-9b21-0800200c9a66', Uuid::RFC_4122],
-            ['ff6f8cb0-c57d-11e1-ab21-0800200c9a66', Uuid::RFC_4122],
-            ['ff6f8cb0-c57d-11e1-bb21-0800200c9a66', Uuid::RFC_4122],
-            ['ff6f8cb0-c57d-11e1-cb21-0800200c9a66', Uuid::RESERVED_MICROSOFT],
-            ['ff6f8cb0-c57d-11e1-db21-0800200c9a66', Uuid::RESERVED_MICROSOFT],
-            ['ff6f8cb0-c57d-11e1-eb21-0800200c9a66', Uuid::RESERVED_FUTURE],
-            ['ff6f8cb0-c57d-11e1-fb21-0800200c9a66', Uuid::RESERVED_FUTURE],
+            ['ff6f8cb0-c57d-11e1-0b21-0800200c9a66', Variant::ReservedNcs],
+            ['ff6f8cb0-c57d-11e1-1b21-0800200c9a66', Variant::ReservedNcs],
+            ['ff6f8cb0-c57d-11e1-2b21-0800200c9a66', Variant::ReservedNcs],
+            ['ff6f8cb0-c57d-11e1-3b21-0800200c9a66', Variant::ReservedNcs],
+            ['ff6f8cb0-c57d-11e1-4b21-0800200c9a66', Variant::ReservedNcs],
+            ['ff6f8cb0-c57d-11e1-5b21-0800200c9a66', Variant::ReservedNcs],
+            ['ff6f8cb0-c57d-11e1-6b21-0800200c9a66', Variant::ReservedNcs],
+            ['ff6f8cb0-c57d-11e1-7b21-0800200c9a66', Variant::ReservedNcs],
+            ['ff6f8cb0-c57d-11e1-8b21-0800200c9a66', Variant::Rfc4122],
+            ['ff6f8cb0-c57d-11e1-9b21-0800200c9a66', Variant::Rfc4122],
+            ['ff6f8cb0-c57d-11e1-ab21-0800200c9a66', Variant::Rfc4122],
+            ['ff6f8cb0-c57d-11e1-bb21-0800200c9a66', Variant::Rfc4122],
+            ['ff6f8cb0-c57d-11e1-cb21-0800200c9a66', Variant::ReservedMicrosoft],
+            ['ff6f8cb0-c57d-11e1-db21-0800200c9a66', Variant::ReservedMicrosoft],
+            ['ff6f8cb0-c57d-11e1-eb21-0800200c9a66', Variant::ReservedFuture],
+            ['ff6f8cb0-c57d-11e1-fb21-0800200c9a66', Variant::ReservedFuture],
         ];
     }
 
@@ -429,7 +430,7 @@ class UuidTest extends TestCase
         /** @var UuidV1 $uuid */
         $uuid = Uuid::uuid1();
         $this->assertInstanceOf(DateTimeInterface::class, $uuid->getDateTime());
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(1, $uuid->getFields()->getVersion());
     }
 
@@ -438,7 +439,7 @@ class UuidTest extends TestCase
         /** @var UuidV1 $uuid */
         $uuid = Uuid::uuid1('0800200c9a66', 0x1669);
         $this->assertInstanceOf(DateTimeInterface::class, $uuid->getDateTime());
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(1, $uuid->getFields()->getVersion());
         $this->assertSame('1669', $uuid->getFields()->getClockSeq()->toString());
         $this->assertSame('0800200c9a66', $uuid->getFields()->getNode()->toString());
@@ -450,7 +451,7 @@ class UuidTest extends TestCase
         /** @var UuidV1 $uuid */
         $uuid = Uuid::uuid1(new Hexadecimal('0800200c9a66'), 0x1669);
         $this->assertInstanceOf(DateTimeInterface::class, $uuid->getDateTime());
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(1, $uuid->getFields()->getVersion());
         $this->assertSame('1669', $uuid->getFields()->getClockSeq()->toString());
         $this->assertSame('0800200c9a66', $uuid->getFields()->getNode()->toString());
@@ -463,7 +464,7 @@ class UuidTest extends TestCase
         $uuid = Uuid::uuid1('7160355e');
 
         $this->assertInstanceOf(DateTimeInterface::class, $uuid->getDateTime());
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(1, $uuid->getFields()->getVersion());
         $this->assertSame('00007160355e', $uuid->getFields()->getNode()->toString());
     }
@@ -474,7 +475,7 @@ class UuidTest extends TestCase
         $uuid = Uuid::uuid1(new Hexadecimal('7160355e'));
 
         $this->assertInstanceOf(DateTimeInterface::class, $uuid->getDateTime());
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(1, $uuid->getFields()->getVersion());
         $this->assertSame('00007160355e', $uuid->getFields()->getNode()->toString());
     }
@@ -485,7 +486,7 @@ class UuidTest extends TestCase
         $uuid = Uuid::uuid1('71B0aD5e');
 
         $this->assertInstanceOf(DateTimeInterface::class, $uuid->getDateTime());
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(1, $uuid->getFields()->getVersion());
         $this->assertSame('000071b0ad5e', $uuid->getFields()->getNode()->toString());
     }
@@ -521,7 +522,7 @@ class UuidTest extends TestCase
         /** @var UuidV1 $uuid */
         $uuid = Uuid::uuid1();
         $this->assertInstanceOf(DateTimeInterface::class, $uuid->getDateTime());
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(1, $uuid->getFields()->getVersion());
     }
 
@@ -530,7 +531,7 @@ class UuidTest extends TestCase
         /** @var UuidV1 $uuid */
         $uuid = Uuid::uuid1(new Hexadecimal((string) (new RandomNodeProvider())->getNode()));
         $this->assertInstanceOf(DateTimeInterface::class, $uuid->getDateTime());
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(1, $uuid->getFields()->getVersion());
     }
 
@@ -539,7 +540,7 @@ class UuidTest extends TestCase
         /** @var UuidV6 $uuid */
         $uuid = Uuid::uuid6();
         $this->assertInstanceOf(DateTimeInterface::class, $uuid->getDateTime());
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(6, $uuid->getFields()->getVersion());
     }
 
@@ -548,7 +549,7 @@ class UuidTest extends TestCase
         /** @var UuidV6 $uuid */
         $uuid = Uuid::uuid6(new Hexadecimal('0800200c9a66'), 0x1669);
         $this->assertInstanceOf(DateTimeInterface::class, $uuid->getDateTime());
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(6, $uuid->getFields()->getVersion());
         $this->assertSame('1669', $uuid->getFields()->getClockSeq()->toString());
         $this->assertSame('0800200c9a66', $uuid->getFields()->getNode()->toString());
@@ -561,7 +562,7 @@ class UuidTest extends TestCase
         $uuid = Uuid::uuid6(new Hexadecimal('7160355e'));
 
         $this->assertInstanceOf(DateTimeInterface::class, $uuid->getDateTime());
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(6, $uuid->getFields()->getVersion());
         $this->assertSame('00007160355e', $uuid->getFields()->getNode()->toString());
     }
@@ -572,7 +573,7 @@ class UuidTest extends TestCase
         $uuid = Uuid::uuid6(new Hexadecimal('71B0aD5e'));
 
         $this->assertInstanceOf(DateTimeInterface::class, $uuid->getDateTime());
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(6, $uuid->getFields()->getVersion());
         $this->assertSame('000071b0ad5e', $uuid->getFields()->getNode()->toString());
     }
@@ -600,7 +601,7 @@ class UuidTest extends TestCase
         /** @var UuidV6 $uuid */
         $uuid = Uuid::uuid6();
         $this->assertInstanceOf(DateTimeInterface::class, $uuid->getDateTime());
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(6, $uuid->getFields()->getVersion());
     }
 
@@ -609,7 +610,7 @@ class UuidTest extends TestCase
         /** @var UuidV6 $uuid */
         $uuid = Uuid::uuid6(new Hexadecimal((string) (new RandomNodeProvider())->getNode()));
         $this->assertInstanceOf(DateTimeInterface::class, $uuid->getDateTime());
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(6, $uuid->getFields()->getVersion());
     }
 
@@ -632,7 +633,7 @@ class UuidTest extends TestCase
         /** @var \Ramsey\Uuid\Rfc4122\UuidInterface $uobj2 */
         $uobj2 = Uuid::uuid3(Uuid::fromString($ns), $name);
 
-        $this->assertSame(2, $uobj1->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uobj1->getFields()->getVariant());
         $this->assertSame(3, $uobj1->getFields()->getVersion());
         $this->assertSame(Uuid::fromString($uuid)->toString(), $uobj1->toString());
         $this->assertTrue($uobj1->equals($uobj2));
@@ -671,7 +672,7 @@ class UuidTest extends TestCase
     {
         /** @var \Ramsey\Uuid\Rfc4122\UuidInterface $uuid */
         $uuid = Uuid::uuid4();
-        $this->assertSame(2, $uuid->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uuid->getFields()->getVariant());
         $this->assertSame(4, $uuid->getFields()->getVersion());
     }
 
@@ -773,7 +774,7 @@ class UuidTest extends TestCase
         /** @var \Ramsey\Uuid\Rfc4122\UuidInterface $uobj2 */
         $uobj2 = Uuid::uuid5(Uuid::fromString($ns), $name);
 
-        $this->assertSame(2, $uobj1->getFields()->getVariant());
+        $this->assertSame(Variant::Rfc4122, $uobj1->getFields()->getVariant());
         $this->assertSame(5, $uobj1->getFields()->getVersion());
         $this->assertSame(Uuid::fromString($uuid)->toString(), $uobj1->toString());
         $this->assertTrue($uobj1->equals($uobj2));
@@ -1159,7 +1160,7 @@ class UuidTest extends TestCase
             $this->assertSame($urn, $uuid->getUrn());
             $this->assertSame($time, $uuid->getFields()->getTimestamp()->toString());
             $this->assertSame($clockSeq, $uuid->getFields()->getClockSeq()->toString());
-            $this->assertSame($variant, $uuid->getFields()->getVariant());
+            $this->assertSame(Variant::from($variant), $uuid->getFields()->getVariant());
             $this->assertSame($version, $uuid->getFields()->getVersion());
         }
     }
@@ -1191,7 +1192,7 @@ class UuidTest extends TestCase
                 'urn' => 'urn:uuid:00000000-0000-0000-0000-000000000000',
                 'time' => '000000000000000',
                 'clock_seq' => '0000',
-                'variant' => Uuid::RESERVED_NCS,
+                'variant' => 0,
                 'version' => null,
             ],
             [
@@ -1211,7 +1212,7 @@ class UuidTest extends TestCase
                 'urn' => 'urn:uuid:00010203-0405-0607-0809-0a0b0c0d0e0f',
                 'time' => '607040500010203',
                 'clock_seq' => '0809',
-                'variant' => Uuid::RESERVED_NCS,
+                'variant' => 0,
                 'version' => null,
             ],
             [
@@ -1231,7 +1232,7 @@ class UuidTest extends TestCase
                 'urn' => 'urn:uuid:02d9e6d5-9467-382e-8f9b-9300a64ac3cd',
                 'time' => '82e946702d9e6d5',
                 'clock_seq' => '0f9b',
-                'variant' => Uuid::RFC_4122,
+                'variant' => 2,
                 'version' => Uuid::UUID_TYPE_HASH_MD5,
             ],
             [
@@ -1251,7 +1252,7 @@ class UuidTest extends TestCase
                 'urn' => 'urn:uuid:12345678-1234-5678-1234-567812345678',
                 'time' => '678123412345678',
                 'clock_seq' => '1234',
-                'variant' => Uuid::RESERVED_NCS,
+                'variant' => 0,
                 'version' => null,
             ],
             [
@@ -1271,7 +1272,7 @@ class UuidTest extends TestCase
                 'urn' => 'urn:uuid:6ba7b810-9dad-11d1-80b4-00c04fd430c8',
                 'time' => '1d19dad6ba7b810',
                 'clock_seq' => '00b4',
-                'variant' => Uuid::RFC_4122,
+                'variant' => 2,
                 'version' => Uuid::UUID_TYPE_TIME,
             ],
             [
@@ -1291,7 +1292,7 @@ class UuidTest extends TestCase
                 'urn' => 'urn:uuid:6ba7b811-9dad-11d1-80b4-00c04fd430c8',
                 'time' => '1d19dad6ba7b811',
                 'clock_seq' => '00b4',
-                'variant' => Uuid::RFC_4122,
+                'variant' => 2,
                 'version' => Uuid::UUID_TYPE_TIME,
             ],
             [
@@ -1311,7 +1312,7 @@ class UuidTest extends TestCase
                 'urn' => 'urn:uuid:6ba7b812-9dad-11d1-80b4-00c04fd430c8',
                 'time' => '1d19dad6ba7b812',
                 'clock_seq' => '00b4',
-                'variant' => Uuid::RFC_4122,
+                'variant' => 2,
                 'version' => Uuid::UUID_TYPE_TIME,
             ],
             [
@@ -1331,7 +1332,7 @@ class UuidTest extends TestCase
                 'urn' => 'urn:uuid:6ba7b814-9dad-11d1-80b4-00c04fd430c8',
                 'time' => '1d19dad6ba7b814',
                 'clock_seq' => '00b4',
-                'variant' => Uuid::RFC_4122,
+                'variant' => 2,
                 'version' => Uuid::UUID_TYPE_TIME,
             ],
             [
@@ -1351,7 +1352,7 @@ class UuidTest extends TestCase
                 'urn' => 'urn:uuid:7d444840-9dc0-11d1-b245-5ffdce74fad2',
                 'time' => '1d19dc07d444840',
                 'clock_seq' => '3245',
-                'variant' => Uuid::RFC_4122,
+                'variant' => 2,
                 'version' => Uuid::UUID_TYPE_TIME,
             ],
             [
@@ -1371,7 +1372,7 @@ class UuidTest extends TestCase
                 'urn' => 'urn:uuid:e902893a-9d22-3c7e-a7b8-d6e313b71d9f',
                 'time' => 'c7e9d22e902893a',
                 'clock_seq' => '27b8',
-                'variant' => Uuid::RFC_4122,
+                'variant' => 2,
                 'version' => Uuid::UUID_TYPE_HASH_MD5,
             ],
             [
@@ -1391,7 +1392,7 @@ class UuidTest extends TestCase
                 'urn' => 'urn:uuid:eb424026-6f54-4ef8-a4d0-bb658a1fc6cf',
                 'time' => 'ef86f54eb424026',
                 'clock_seq' => '24d0',
-                'variant' => Uuid::RFC_4122,
+                'variant' => 2,
                 'version' => Uuid::UUID_TYPE_RANDOM,
             ],
             [
@@ -1411,7 +1412,7 @@ class UuidTest extends TestCase
                 'urn' => 'urn:uuid:f81d4fae-7dec-11d0-a765-00a0c91e6bf6',
                 'time' => '1d07decf81d4fae',
                 'clock_seq' => '2765',
-                'variant' => Uuid::RFC_4122,
+                'variant' => 2,
                 'version' => Uuid::UUID_TYPE_TIME,
             ],
             [
@@ -1431,7 +1432,7 @@ class UuidTest extends TestCase
                 'urn' => 'urn:uuid:fffefdfc-fffe-fffe-fffe-fffefdfcfbfa',
                 'time' => 'ffefffefffefdfc',
                 'clock_seq' => '3ffe',
-                'variant' => Uuid::RESERVED_FUTURE,
+                'variant' => 7,
                 'version' => null,
             ],
             [
@@ -1451,7 +1452,7 @@ class UuidTest extends TestCase
                 'urn' => 'urn:uuid:ffffffff-ffff-ffff-ffff-ffffffffffff',
                 'time' => 'fffffffffffffff',
                 'clock_seq' => '3fff',
-                'variant' => Uuid::RESERVED_FUTURE,
+                'variant' => 7,
                 'version' => null,
             ],
         ];