symfony 2.8 phpunit default test returning failed

Question

I have following default test in PHPUnit and it is returning failed. I have accessed the path from the browser and it is displaying fine.

class DefaultControllerTest extends WebTestCase
{
    public function testIndex()
    {
        $client = static::createClient();

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

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

config_test.yml

imports:
    - { resource: config_dev.yml }

framework:
    test: ~
    session:
        storage_id: session.storage.mock_file
    profiler:
        enabled: true # we want the profiler service to be defined
        collect: false

web_profiler:
    toolbar: false
    intercept_redirects: false

swiftmailer:
    disable_delivery: true

Answer 1

after checking logs/tests.log . The error was coming from translation messages, few messages didn't have opening and closing quote, after adding that it is displaying success message now.