Tests\Feature\BlogTest > user can delete post 162 Illuminate\Encryption\MissingAppKeyException No application encryption key has been specified.

PHP
Tests\Feature\BlogTest > user can delete post 162
   Illuminate\Encryption\MissingAppKeyException 

  No application encryption key has been specified.

php artisan key:generate --env=testing #You should use the php artisan key:generate command to generate this key"php artisan key:generate
Source

Also in PHP: