Install laravel to cloud9 and phpunit testing error

When I run program below,error has occured.

(i) In Cloud9, install laravel

(ii) copy "./app/Http/route.php" to "./app/Http/route_a.php" add some lines in route_a.php

Route::get('/test/', function () {
    echo 'test';
});

(iii) I edit "./tests/ExampleTest.php".

<?php

use Illuminate\Foundation\Testing\WithoutMiddleware;
use Illuminate\Foundation\Testing\DatabaseMigrations;
use Illuminate\Foundation\Testing\DatabaseTransactions;
use Illuminate\Filesystem\Filesystem;

class ExampleTest extends TestCase
{
    /**
     * A basic functional test example.
     *
     * @return void
     */
    public function testBasicExample()
    {
        $this->editRoute();

        $this->visit('/')
             ->see('Laravel 5');
        $this->visit('http://ift.tt/23dCume');
    }

    private function editRoute(){
        $this->files = new Filesystem;
        $this->files->move( './app/Http/routes.php', './app/Http/routes_b.php');
        $this->files->move( './app/Http/routes_a.php', './app/Http/routes.php');
        Artisan::call('clear-compiled');
        Artisan::call('cache:clear');        
    }
}

(iv) run phpunit

php ./vendor/bin/phpunit

And error has occured below.

There was 1 failure:

1) ExampleTest::testBasicExample
A request to [http://localhost/test] failed. Received status code [404].

After error, commentout "editRoute()", and run phpunit again, then there is no error.

Please Someone help me. Thank you.