Add tool name validation for SEP-986 (#140)

tests/Unit/Capability/Tool/NameValidatorTest.php

@@ -0,0 +1,56 @@
+<?php
+
+/*
+ * This file is part of the official PHP MCP SDK.
+ *
+ * A collaboration between Symfony and the PHP Foundation.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Mcp\Tests\Unit\Capability\Tool;
+
+use Mcp\Capability\Tool\NameValidator;
+use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\TestCase;
+
+final class NameValidatorTest extends TestCase
+{
+    #[DataProvider('provideValidNames')]
+    public function testValidNames(string $name): void
+    {
+        $this->assertTrue((new NameValidator())->isValid($name));
+    }
+
+    public static function provideValidNames(): array
+    {
+        return [
+            ['my_tool'],
+            ['MyTool123'],
+            ['my.tool'],
+            ['my-tool'],
+            ['my/tool'],
+            ['my_tool-01.02'],
+            ['my_long_toolname_that_is_exactly_sixty_four_characters_long_1234'],
+        ];
+    }
+
+    #[DataProvider('provideInvalidNames')]
+    public function testInvalidNames(string $name): void
+    {
+        $this->assertFalse((new NameValidator())->isValid($name));
+    }
+
+    public static function provideInvalidNames(): array
+    {
+        return [
+            [''],
+            ['my tool'],
+            ['my@tool'],
+            ['my!tool'],
+            ['my_tool#1'],
+            ['this_tool_name_is_way_too_long_because_it_exceeds_the_sixty_four_character_limit_set_by_the_validator'],
+        ];
+    }
+}