00_DefaultControllerTest.php

<?php

namespace Kris\JunkBundle\Tests\Controller;

use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;

class DefaultControllerTest extends WebTestCase
{
    /**
     * @dataProvider asdf
     */
    public function testIndex()
    {
        $client = static::createClient();

        $crawler = $client->request('GET', '/hello/Fabien');

        $this->assertTrue($crawler->filter('html:contains("Hello Fabien")')->count() > 0);
    }

    public function asdf()
    {
        return array_fill(0, 500, array());
    }
}

01_before.txt

~/Sites/symfony/standard (2.0) $ phpunit -c app/
PHPUnit 3.6.10 by Sebastian Bergmann.

Configuration read from /Users/kriswallsmith/Sites/symfony/standard/app/phpunit.xml.dist

...............................................................  63 / 500 ( 12%)
............................................................... 126 / 500 ( 25%)
............................................................... 189 / 500 ( 37%)
............................................................... 252 / 500 ( 50%)
............................................................... 315 / 500 ( 63%)
............................................................... 378 / 500 ( 75%)
............................................................... 441 / 500 ( 88%)
...........................................................

Time: 31 seconds, Memory: 289.50Mb

OK (500 tests, 500 assertions)

02_after.txt

~/Sites/symfony/standard (2.0) $ phpunit -c app/
PHPUnit 3.6.10 by Sebastian Bergmann.

Configuration read from /Users/kriswallsmith/Sites/symfony/standard/app/phpunit.xml.dist

...............................................................  63 / 500 ( 12%)
............................................................... 126 / 500 ( 25%)
............................................................... 189 / 500 ( 37%)
............................................................... 252 / 500 ( 50%)
............................................................... 315 / 500 ( 63%)
............................................................... 378 / 500 ( 75%)
............................................................... 441 / 500 ( 88%)
...........................................................

Time: 40 seconds, Memory: 51.25Mb

OK (500 tests, 500 assertions)

Why there is a decrease in memory usage with "asdf" enabled ?

See http://kriswallsmith.net/post/18029585104/faster-phpunit