class TestServiceProvider implements ServiceProviderInterface
{
    public function register(BaseApplication $app)
    {
        // ブロックのルーティング設定。ルーティング名の接頭辞にblock_を付ける
        $app->match('/block/test', '\Plugin\Test\Controller\Block\TestBlockController::index')
            ->bind('block_test');
    }
}

class TestBlockController
{
    public function index(Application $app, Request $request)
    {
        $Tests = $app['eccube.repository.test']->findAll();
        echo "OK";  // 呼ばれない

        return $app['view']->render("Block/test.twig", array(
            'Tests' => $Tests,
        ));
    }
}

<nav id="test" class="drawer_block pc">
    <ul class="test-nav">
    {% for Test in Tests %}
        <li>
            <a>
                {% Test.name %}
            </a>
        </li>
    {% endfor %}
    </ul>
</nav>