phpunit test passes, page load in browser fails in Symfony 2 - symfony

Question

I am new to phpunit testing and did a very simple test looking for status code.
The test passes when I run:
bin\phpunit -c app src\AppBundle\Tests\Controller\StarLinX\TravelControllerTest.php
PHPUnit 4.6.10 by Sebastian Bergmann and contributors.
Configuration read from C:\PhpstormProjects\dir\app\phpunit.xml.dist
.
Time: 6.03 seconds, Memory: 20.00Mb
OK (1 test, 1 assertion)
But when I load the page in the browser, an exception is thrown rendering the twig file with status code 500.
I thought maybe this was a cache issue, so I cleared cache in --env=dev, prod and test.
How do I troubleshoot this error?
This is my test file:
namespace AppBundle\Tests\Controller\StarLinX;
use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;
class TravelControllerTest extends WebTestCase {
public function testGET() {
// Create a new client to browse the application
$client = static::createClient();
// get the page
$crawler = $client->request('GET', '/travel/aaaaa');
$this->assertEquals(200, $client->getResponse()->getStatusCode(), "Unexpected HTTP status code for GET /travel/aaaaa");
}
}
This is the error that is thrown when running in the dev environment:
An exception has been thrown during the rendering of a template ("Notice: Array to string conversion")
So after a little more analysis, I find that the error around {{ weatherInfo }} which should be {{ weatherInfo.now }}. This throws an error when running the development environment. In production, twig simply displays Array.
Is that normal behavior?

Answer 1

As it's written your test only check the error status, the test is not specific enough. What if it displayed another page? The test would still pass.
You should add some other tests in order to ensure that the page is properly displayed:
// …
$this->assertEquals(200, $client->getResponse()->getStatusCode(),
"Unexpected HTTP status code for GET /travel/aaaaa");
// Check that the page has a title.
$this->assertSame(
1,
$crawler->filter('title')->count()
);
// Check that the page has a correct title.
$this->assertSame(
'Travel',
$crawler->filter('title')->text()
);
// Check something in the content
$this->assertSame(
'Hello, World!',
$crawler->filter('body > div#content')->text()
);
If you don't have enough information to debug your code, tou can access to the page content which usually contain the error message:
die($this->client->getResponse()->getContent());