Laravel Dusk in a non-laravel (Symfony) app

ExampleTest.php

<?php

namespace App\Tests\Browser;

use App\Tests\HasDuskBrowser;

class ExampleTest extends \PHPUnit_Framework_TestCase
{
    use HasDuskBrowser;
    
    public function testBasicExample()
    {
        $this->browse(function ($browser) use ($user) {
            $browser->visit('/login')
                    ->type('username', 'myusername')
                    ->type('password', 'secret')
                    ->press('Login')
                    ->assertPathIs('/home');
        });
    }
}

HasDuskBrowser.php

<?php

namespace App\Tests;

use Facebook\WebDriver\Remote\DesiredCapabilities;
use Facebook\WebDriver\Remote\RemoteWebDriver;
use Illuminate\Support\Collection;
use Laravel\Dusk\Browser;
use Laravel\Dusk\SupportsChrome;
use Symfony\Component\Filesystem\Filesystem;
use Symfony\Component\Finder\Finder;

/**
 * @see Laravel\Dusk\TestCase
 */
trait HasDuskBrowser
{
    use SupportsChrome;

    protected static $browsers = [];
    protected static $afterClassCallbacks = [];

    /**
     * @beforeClass
     */
    public static function setupDuskClass()
    {
        static::startChromeDriver();
    }

    /**
     * @afterClass
     */
    public static function teardownDuskClass()
    {
        Collection::make(static::$browsers)->each(function (Browser $browser) {
            $browser->quit();
        });

        static::$browsers = collect();

        foreach (static::$afterClassCallbacks as $callback) {
            $callback();
        }
    }

    public static function afterClass(\Closure $callback)
    {
        static::$afterClassCallbacks[] = $callback;
    }

    /**
     * @before
     */
    public function setupDuskTest()
    {
        Browser::$baseUrl = $_SERVER['DUSK_BASE_URL'];
        Browser::$screenshotDir = realpath($_SERVER['DUSK_SCREENSHOT_DIR']);

        $this->clearExistingScreenshots(Browser::$screenshotDir);
    }

    public function browse(\Closure $callback)
    {
        $browsers = $this->createBrowsersFor($callback);

        try {
            $callback(...$browsers->all());
        } catch (\Exception $e) {
            $this->captureFailuresFor($browsers);

            throw $e;
        } catch (\Throwable $e) {
            $this->captureFailuresFor($browsers);

            throw $e;
        } finally {
            static::$browsers = $this->closeAllButPrimary($browsers);
        }
    }

    protected function createBrowsersFor(\Closure $callback)
    {
        if (count(static::$browsers) === 0) {
            static::$browsers = collect([new Browser($this->createWebDriver())]);
        }

        $additional = $this->browsersNeededFor($callback) - 1;

        for ($i = 0; $i < $additional; ++$i) {
            static::$browsers->push(new Browser($this->createWebDriver()));
        }

        return static::$browsers;
    }

    protected function browsersNeededFor(\Closure $callback)
    {
        return (new \ReflectionFunction($callback))->getNumberOfParameters();
    }

    protected function closeAllButPrimary(Collection $browsers)
    {
        $browsers->slice(1)->each(function (Browser $browser) {
            $browser->quit();
        });

        return $browsers->take(1);
    }

    protected function createWebDriver()
    {
        return RemoteWebDriver::create(
            'http://localhost:9515', DesiredCapabilities::chrome()
        );
    }

    protected function captureFailuresFor(Collection $browsers)
    {
        $browsers->each(function (Browser $browser, $key) {
            $browser->screenshot(sprintf('%s-%s',
                $this->getScreenshotPrefix(),
                $key
            ));
        });
    }

    protected function getScreenshotPrefix()
    {
        return sprintf('failure-%s-%s',
            class_basename($this),
            $this->getName()
        );
    }

    protected function clearExistingScreenshots($dir)
    {
        $filesystem = new Filesystem();

        if (!is_dir($dir)) {
            $filesystem->mkdir($dir);
        }

        $files = Finder::create()
            ->files()
            ->in($dir)
            ->name($this->getScreenshotPrefix().'*')
        ;

        $filesystem->remove($files);
    }
}

phpunit.xml

<?xml version="1.0" encoding="UTF-8"?>
<phpunit>
    <php>
        <!-- ... -->
        <server name="DUSK_SCREENSHOT_DIR" value="var/screenshots" />
        <server name="DUSK_BASE_URL" value="http://127.0.0.1:8000" />      
         <!-- ... -->
    </php>

    <!-- ... -->
</phpunit>