Script php artisan clear-compiled handling the post-update-cmd event returned with an error (Duplicating Laravel 5 project)

I'm trying to duplicate a Laravel 5 project and got this error while running composer update:

Script php artisan clear-compiled handling the post-update-cmd event  returned with an error
[RuntimeException]
Error Output: PHP Fatal error:  Class 'Illuminate\Routing\ControllerServiceProvider' not found in /www/sites/myproject/wwwroot/vendor/laravel/framework/src/Illuminate/Foundation/ProviderRepository.php on line 146
PHP Fatal error:  Uncaught exception 'Illuminate\Contracts\Container\BindingResolutionException' with message 'Target [Illuminate\Contracts\Debug\ExceptionHandler] is not instantiable.' in /www/sites/myproject/wwwroot/vendor/laravel/framework/src/Illuminate/Container/Container.php:752
Stack trace:
#0 /www/sites/myproject/wwwroot/vendor/laravel/framework/src/Illuminate/Container/Container.php(633): Illuminate\Container\Container->build('Illuminate\\Cont...', Array)  
#1 /www/sites/myproject/wwwroot/vendor/laravel/framework/src/Illuminate/Foundation/Application.php(687): Illuminate\Container\Container->make('Illuminate\\Cont...', Array)                                                               
#2 /www/sites/myproject/wwwroot/vendor/laravel/framework/src/Illuminate/Foundation/Bootstrap/HandleExceptions.php(154): Illuminate\Foundation\Application->make('Illuminate\\Cont...')                                       
#3 /www/sites/myproject/wwwroot/vendor/laravel/framework/src/Illuminate/Foundation/Bootstrap/HandleExceptions.php(79): Illuminate\Foundation\Bootstrap\HandleExceptions->getExceptionHandler()                       
#4 /www/sites/myproject/wwwroot/vendor/laravel/framework/ in /www/sites/myproject/wwwroot/vendor/laravel/framework/src/Illuminate/Container/Container.php on line 752

I'm on a local web stack on which I already created a new Laravel project with succes.

To get this error:

1. I dowloaded all folders from the production project to my local project folder.
2. I deleted the vendors folder and the composer.lock file
3. I edit the .env file to reflect the local environnement and turn debuging mode on; looking like this: APP_ENV=local, APP_DEBUG=true, APP_KEY=SomeRandomString, DB_USERNAME=homestead, DB_PASSWORD=homestead,
4. I run composer self-update
5. I run composer install
6. Then composer update, and got the error.

I'm brand new to Laravel, coming from Zend Framework world, so I would like some advice on where I should dig this please.

Others points:

1. I get a blank page in browser since the beginning
2. I can display successfully a test index.php file in the public folder from the browser.
3. The display error is on in the php.ini file and it's the good php.ini file :)

Hope some help, thanks in advance :)

via Chebli Mohamed