---
title: Writing custom PHPStan rules for Drupal projects
date: 2024-09-22
permalink: daily/2024/09/22/writing-custom-phpstan-rules-for-drupal-projects
tags:
  - software-development
  - drupal
  - php
  - phpstan
cta: ~
snippet: |
  I wrote a custom PHPStan rule!
drupal_planet: true
---

Today, I watched a video recording of a session by Ondřej Mirtes - the creator of PHPStan - on writing custom rules for PHPStan.

After explaining how to write them, he showed some examples of custom rules - one of which was ensuring a `Person` class couldn't be created outside of a `PersonRepository` class.

This seemed straightforward so I thought about how I could do something similar within my [Drupal automated testing email course][0] to check my Drupal code.

Similar to Ondřej's example, I wondered if I could enforce that no post nodes should be created outside of the `PostBuilder` class by searching for any code like `Node::create(['type' => 'post'])`.

I was able to get a version working quickly and have [posted it as a gist][1].

I'm sure some improvements can be made, but it was a successful experiment and something I can see me using more in the future.

[0]: {{site.url}}/atdc
[1]: https://gist.github.com/opdavies/a2f9d92cf3b67db6a64b9fca4e4e6697