Setting up an in-memory SQLite database for testing in Laravel 5.4

I am working on developing a browser test suite for a Laravel 5.4 application using Dusk. One of the tests checks to see if the object has been created, and since this is a browser check, the value is saved to the database when the submit button is clicked. Obviously I don't want my database to be cluttered with test data, and there is also a problem as the object name must be unique and therefore the test will fail after the first run. I decided that the best solution to this problem was to implement a test database that is cleaned up at the end of each test cycle. However, I am having trouble getting it set up.

Currently my code is not throwing any errors, but phpunit simply won't use the test database. I installed the code when I was looking into how to implement the database, but I'm not sure what to do with it. Here is the code I have:

.env

DB_CONNECTION=mysql

      

        
        
        
      

    

.env.testing

APP_ENV=testing
APP_DEBUG=true
APP_KEY=this_has_a_real_key
APP_URL=http://localhost:8000

DB_CONNECTION=sqlite_testing

      

        
        
        
      

    

database.php

'default' => env('DB_CONNECTION', 'mysql'),
'connections' => [

        ...

        'sqlite_testing' => [
            'driver'   => 'sqlite',
            'database' => ':memory:',
            'prefix'   => '',
        ],

        ...

      

        
        
        
      

    

phpunit.xml

<env name="DB_CONNECTION" value="sqlite_testing" />

      

        
        
        
      

    

DuskTestCase.php

abstract class DuskTestCase extends BaseTestCase
{
    /**
     * Creates the application.
     *
     * @return \Illuminate\Foundation\Application
     */
    public function createApplication()
    {
        putenv('DB_CONNECTION=sqlite_testing');

        $app = require __DIR__ . '/../bootstrap/app.php';

        $app->make('Illuminate\Contracts\Console\Kernel')->bootstrap();

        return $app;
    }

    public function setUp()
    {
        parent::setUp();
        //Artisan::call('migrate:refresh');
        Artisan::call('migrate');
        Artisan::call('db:seed');
    }

        /**
     * Prepare for Dusk test execution.
     *
     * @beforeClass
     * @return void
     */
    public static function prepare()
    {
        static::startChromeDriver();
    }

    /**
     * Create the RemoteWebDriver instance.
     *
     * @return \Facebook\WebDriver\Remote\RemoteWebDriver
     */
    protected function driver()
    {
        return RemoteWebDriver::create(
            'http://localhost:9515', DesiredCapabilities::chrome()
        );
    }


    public function tearDown()
    {
        Artisan::call('migrate:reset');
        parent::tearDown();
    }

}

      

        
        
        
      

    

DuskTestCase and .env.testing are shown in full, the rest have corresponding parts. How can I modify this code to make phpunit recognize and use my sqlite_testing database?