phpstan example

composer.json

{
    "name": "foo",
    "type": "project",
    "require": {
        "symfony/http-foundation": "^4.2",
        "phpstan/phpstan": "^0.11.0"
    },
    "autoload": {
        "classmap": [
            "Controller.php"
        ]
    }
}

Controller.php

<?php declare(strict_types = 1);
require_once __DIR__ . '/vendor/autoload.php';

use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;

class Controller
{
    public function getFoo(Request $request)
    {
        $userId = $request->get('userid');

        if (isset($userId)) {
            $userId = (int)($userId);
        }
        
        // ...

        $response = new Response();

        if (isset($userId)) {
            $response->headers->add(['userId' => $userId]);
        }
        
        return $response;
    }
}

gistfile1.txt

$ vender/bin/phpstan analyse --level max Controller.php 
 1/1 [▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓] 100%

 ------ ---------------------------------------------------------------- 
  Line   Controller.php                                                  
 ------ ---------------------------------------------------------------- 
  21     Variable $userId in isset() always exists and is not nullable.  
 ------ ---------------------------------------------------------------- 

                                                                                                                        
 [ERROR] Found 1 error