Add TypeParsingBench for phpbench

Isolates type parsing performance: 9 realistic type strings, 1000 revs x 5 iterations, comparing raw Parser vs CachingParser.

Author: NikoGrano

tests/Benchmark/Performance/TypeParsingBench.php

@@ -0,0 +1,64 @@
+<?php
+
+declare(strict_types=1);
+
+namespace JMS\Serializer\Tests\Benchmark\Performance;
+
+use JMS\Serializer\Type\CachingParser;
+use JMS\Serializer\Type\Parser;
+use PhpBench\Benchmark\Metadata\Annotations\BeforeMethods;
+use PhpBench\Benchmark\Metadata\Annotations\Iterations;
+use PhpBench\Benchmark\Metadata\Annotations\Revs;
+
+/**
+ * @BeforeMethods({"setUp"})
+ * @Iterations(5)
+ * @Revs(1000)
+ */
+class TypeParsingBench
+{
+    /**
+     * @var Parser
+     */
+    private $parser;
+
+    /**
+     * @var CachingParser
+     */
+    private $cachingParser;
+
+    /**
+     * @var string[]
+     */
+    private $types = [
+        'string',
+        'int',
+        'array<string>',
+        'array<string, int>',
+        'DateTime<\'Y-m-d\'>',
+        'DateTime<\'Y-m-d\TH:i:s\', \'UTC\'>',
+        'array<App\Entity\User>',
+        'Foo<Bar<Baz, Qux>>',
+        'DateTime<null, null, [\'Y-m-d\TH:i:s\', \'Y-m-d\TH:i:sP\']>',
+    ];
+
+    public function setUp(): void
+    {
+        $this->parser = new Parser();
+        $this->cachingParser = new CachingParser(new Parser());
+    }
+
+    public function benchParserWithoutCache(): void
+    {
+        foreach ($this->types as $type) {
+            $this->parser->parse($type);
+        }
+    }
+
+    public function benchParserWithCache(): void
+    {
+        foreach ($this->types as $type) {
+            $this->cachingParser->parse($type);
+        }
+    }
+}