Issue after installing on Lumen 5.2

[hugoalvarado]

Hello,

I just installed the Integrated testing framework on Lumen, the install itself completed without fuss, but when I run my first test I get this error:

[Symfony\Component\Debug\Exception\FatalErrorException]
Access level to Laravel\Lumen\Testing\TestCase::seeInDatabase() must be public (as in class Laracasts\Integrated\Emulator)

Am I doing something wrong?

My base test class extends Laracasts\Integrated\Extensions\Lumen

use Laracasts\Integrated\Extensions\Lumen as IntegrationTest;

abstract class FunctionalTest extends IntegrationTest{...}

class LoginFunctionalTest extends FunctionalTest
{
    public function itVerifiesLoginPageLoads()
    {
        $this->visit('/');
    }
}

This is my composer file:

"require": {
"php": ">=5.5.9",
"laravel/lumen-framework": "5.2.",
"vlucas/phpdotenv": "~2.2",
"generationtux/jwt-artisan": "^0.1.7",
"illuminate/mail": "^5.2",
"guzzlehttp/guzzle": "5.3.1",
"smalot/pdfparser": ""
},
"require-dev": {
"fzaninotto/faker": "~1.4",
"phpunit/phpunit": "~4.0",
"laracasts/integrated": "^0.15.6"
},

This is the error trace:

vagrant@homestead:~/Code/Lumen$ phpunit --filter itVerifiesLoginPageLoads FeesFunctionalTest tests/FeesFunctionalTest.php
PHP Fatal error: Access level to Laravel\Lumen\Testing\TestCase::seeInDatabase() must be public (as in class Laracasts\Integrated\Emulator) in /home/vagrant/C
ode/Lumen/vendor/laracasts/integrated/src/Extensions/Lumen.php on line 9
PHP Stack trace:
PHP 1. {main}() /home/vagrant/Code/Lumen/vendor/phpunit/phpunit/phpunit:0
PHP 2. PHPUnit_TextUI_Command::main() /home/vagrant/Code/Lumen/vendor/phpunit/phpunit/phpunit:47
PHP 3. PHPUnit_TextUI_Command->run() /home/vagrant/Code/Lumen/vendor/phpunit/phpunit/src/TextUI/Command.php:100
PHP 4. PHPUnit_Runner_BaseTestRunner->getTest() /home/vagrant/Code/Lumen/vendor/phpunit/phpunit/src/TextUI/Command.php:122
PHP 5. PHPUnit_Runner_BaseTestRunner->loadSuiteClass() /home/vagrant/Code/Lumen/vendor/phpunit/phpunit/src/Runner/BaseTestRunner.php:64
PHP 6. PHPUnit_Runner_StandardTestSuiteLoader->load() /home/vagrant/Code/Lumen/vendor/phpunit/phpunit/src/Runner/BaseTestRunner.php:123
PHP 7. PHPUnit_Util_Fileloader::checkAndLoad() /home/vagrant/Code/Lumen/vendor/phpunit/phpunit/src/Runner/StandardTestSuiteLoader.php:39
PHP 8. PHPUnit_Util_Fileloader::load() /home/vagrant/Code/Lumen/vendor/phpunit/phpunit/src/Util/Fileloader.php:38
PHP 9. include_once() /home/vagrant/Code/Lumen/vendor/phpunit/phpunit/src/Util/Fileloader.php:56
PHP 10. spl_autoload_call() /home/vagrant/Code/Lumen/tests/FeesFunctionalTest.php:3
PHP 11. Composer\Autoload\ClassLoader->loadClass() /home/vagrant/Code/Lumen/tests/FeesFunctionalTest.php:3
PHP 12. Composer\Autoload\includeFile() /home/vagrant/Code/Lumen/vendor/composer/ClassLoader.php:301
PHP 13. include() /home/vagrant/Code/Lumen/vendor/composer/ClassLoader.php:414
PHP 14. spl_autoload_call() /home/vagrant/Code/Lumen/tests/FunctionalTest.php:5
PHP 15. Composer\Autoload\ClassLoader->loadClass() /home/vagrant/Code/Lumen/tests/FunctionalTest.php:5
PHP 16. Composer\Autoload\includeFile() /home/vagrant/Code/Lumen/vendor/composer/ClassLoader.php:301
PHP 17. include() /home/vagrant/Code/Lumen/vendor/composer/ClassLoader.php:414