Silex web test fails

Question

I'm trying to write a simple web test to test my silex api using phpunit but I keep getting this error when i try to run it..

1) App\Tests\BlogControllerTest::testInitialPage
TypeError: Argument 1 passed to Symfony\Component\HttpKernel\Client::__construct() must implement interface Symfony\Component\HttpKernel\HttpKernelInterface, null given, called in C:\vendor\silex\silex\src\Silex\WebTestCase.php on line 63

This is my web test

<?php
namespace App\Tests;

use Silex\WebTestCase;

class BlogControllerTest extends WebTestCase
{

    public function createApplication()
    {
        require dirname(dirname(__DIR__)) . '/src/Application.php';
    }
    public function testInitialPage()
    {
        $client  = $this->createClient();
        $crawler = $client->request('GET', '/Blog/1');

        $this->assertTrue($client->getResponse()->isOk());

    }
}

The content of my Composer file:

{
    "require": {
        "silex/silex": "~2.0",
        "symfony/validator": "^4.0",
        "crell/api-problem": "~1.7",
        "tobiassjosten/responsible-service-provider": "^1.0"
    },
    "require-dev": {
        "phpunit/phpunit": "6",
        "symfony/browser-kit": "^4.0",
        "symfony/css-selector": "^4.0"
    },
    "autoload": {
        "psr-4": {
            "App\\": "src/",
            "Tests\\": "tests/"
        }
    }
}

Answer 1

From documentation:

For your WebTestCase, you will have to implement a createApplication method, which returns your application instance:

public function createApplication()
{
    // app.php must return an Application instance
    return require __DIR__.'/path/to/app.php';
}

So here's what you need:

public function createApplication()
{
    return new Application();
}

But in the most cases it would be better to return configured application, from your bootstrap (bootstrap example):

public function createApplication()
{
    require __DIR__.'../web/index-test.php'; // path to your bootstrap file
    return $app;
}