Add TypeConversionPerformanceTest

tests/Doctrine/Tests/DBAL/Performance/TypeConversionPerformanceTest.php

+<?php
+
+namespace Doctrine\Tests\DBAL\Performance;
+
+use Doctrine\DBAL\Types\Type;
+use Doctrine\Tests\DbalPerformanceTestCase;
+
+/**
+ * Class TypeConversionPerformanceTest
+ * @package Doctrine\Tests\DBAL\Performance
+ * @author Bill Schaller
+ */
+class TypeConversionPerformanceTest extends DbalPerformanceTestCase
+{
+    /**
+     * MAXIMUM TIME: 2 seconds
+     */
+    public function testDateTimeTypeConversionPerformance100000Items()
+    {
+        $value = new \DateTime;
+        $start = microtime(true);
+        $type = Type::getType("datetime");
+        $platform = $this->_conn->getDatabasePlatform();
+        for ($i = 0; $i < 100000; $i++) {
+            $type->convertToDatabaseValue($value, $platform);
+        }
+        echo __FUNCTION__ . " - " . (microtime(true) - $start) . " seconds" . PHP_EOL;
+    }
+}