Add StaticNodeProvider to make it easier to use a static node

src/Provider/Node/StaticNodeProvider.php

@@ -0,0 +1,79 @@
+<?php
+
+/**
+ * This file is part of the ramsey/uuid library
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ *
+ * @copyright Copyright (c) Ben Ramsey <ben@benramsey.com>
+ * @license http://opensource.org/licenses/MIT MIT
+ */
+
+declare(strict_types=1);
+
+namespace Ramsey\Uuid\Provider\Node;
+
+use Ramsey\Uuid\Exception\InvalidArgumentException;
+use Ramsey\Uuid\Provider\NodeProviderInterface;
+use Ramsey\Uuid\Type\Hexadecimal;
+
+use function dechex;
+use function hexdec;
+use function str_pad;
+use function substr;
+
+use const STR_PAD_LEFT;
+
+/**
+ * StaticNodeProvider provides a static node value with the multicast bit set
+ *
+ * @link http://tools.ietf.org/html/rfc4122#section-4.5 RFC 4122, § 4.5: Node IDs that Do Not Identify the Host
+ */
+class StaticNodeProvider implements NodeProviderInterface
+{
+    /**
+     * @var Hexadecimal
+     */
+    private $node;
+
+    /**
+     * @param Hexadecimal $node The static node value to use
+     */
+    public function __construct(Hexadecimal $node)
+    {
+        if (strlen($node->toString()) > 12) {
+            throw new InvalidArgumentException(
+                'Static node value cannot be greater than 12 hexadecimal characters'
+            );
+        }
+
+        $this->node = $this->setMulticastBit($node);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getNode()
+    {
+        return $this->node->toString();
+    }
+
+    /**
+     * Set the multicast bit for the static node value
+     */
+    private function setMulticastBit(Hexadecimal $node): Hexadecimal
+    {
+        $nodeHex = str_pad($node->toString(), 12, '0', STR_PAD_LEFT);
+        $firstOctet = substr($nodeHex, 0, 2);
+
+        $firstOctet = str_pad(
+            dechex(hexdec($firstOctet) | 0x01),
+            2,
+            '0',
+            STR_PAD_LEFT
+        );
+
+        return new Hexadecimal($firstOctet . substr($nodeHex, 2));
+    }
+}

src/Rfc4122/UuidV2.php

@@ -22,6 +22,8 @@ use Ramsey\Uuid\Rfc4122\FieldsInterface as Rfc4122FieldsInterface;
 use Ramsey\Uuid\Type\Integer as IntegerObject;
 use Ramsey\Uuid\Uuid;
 
+use function hexdec;
+
 /**
  * DCE Security version, or version 2, UUIDs include local domain identifier,
  * local ID for the specified domain, and node values that are combined into a

tests/Provider/Node/StaticNodeProviderTest.php

@@ -0,0 +1,58 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Ramsey\Uuid\Test\Provider\Node;
+
+use Ramsey\Uuid\Exception\InvalidArgumentException;
+use Ramsey\Uuid\Provider\Node\StaticNodeProvider;
+use Ramsey\Uuid\Test\TestCase;
+use Ramsey\Uuid\Type\Hexadecimal;
+
+class StaticNodeProviderTest extends TestCase
+{
+    /**
+     * @dataProvider provideNodeForTest
+     */
+    public function testStaticNode(Hexadecimal $node, string $expectedNode): void
+    {
+        $staticNode = new StaticNodeProvider($node);
+
+        $this->assertSame($expectedNode, $staticNode->getNode());
+    }
+
+    /**
+     * @phpcsSuppress SlevomatCodingStandard.TypeHints.ReturnTypeHint.MissingTraversableTypeHintSpecification
+     */
+    public function provideNodeForTest(): array
+    {
+        return [
+            [
+                'node' => new Hexadecimal('0'),
+                'expectedNode' => '010000000000',
+            ],
+            [
+                'node' => new Hexadecimal('1'),
+                'expectedNode' => '010000000001',
+            ],
+            [
+                'node' => new Hexadecimal('f2ffffffffff'),
+                'expectedNode' => 'f3ffffffffff',
+            ],
+            [
+                'node' => new Hexadecimal('ffffffffffff'),
+                'expectedNode' => 'ffffffffffff',
+            ],
+        ];
+    }
+
+    public function testStaticNodeThrowsExceptionForTooLongNode(): void
+    {
+        $this->expectException(InvalidArgumentException::class);
+        $this->expectExceptionMessage(
+            'Static node value cannot be greater than 12 hexadecimal characters'
+        );
+
+        new StaticNodeProvider(new Hexadecimal('1000000000000'));
+    }
+}