Webiny\Component\Bootstrap\ApplicationClasses\Application::getApplicationConfig PHP Method

    public function getApplicationConfig($query = '', $default = null)
    {
        if ($query == '') {
            return $this->environment->getApplicationConfig();
        } else {
            return $this->environment->getApplicationConfig()->get($query, $default);
        }
    }

 public function testGetApplicationConfigQueryDefault()
 {
     $env = Environment::getInstance();
     $env->initializeEnvironment(__DIR__ . '/../DemoApp/');
     $app = new Application($env);
     $appConfig = $app->getApplicationConfig('Test', 'default');
     $this->assertSame('default', $appConfig);
 }