I have lately been facing an issue where my artisan outputs a lot of strange characters such as ?[32m. It seems to be an issue with the latest Laravel.
Until now I have managed to read around it, but it still annoyed me.
Finally today I found the solution in this thread: https://laracasts.com/discuss/channels/laravel/php-artisan-not-working-4?page=1#reply=543852
Solution
As Nakov says, you must have this package in your project to make it look correct again:
composer require symfony/console:4.3.4