Classes should be final

composer.json

@@ -135,6 +135,13 @@
     },
     "require-dev": {
         "drupal/core-dev": "^11.1",
+        "phpat/phpat": "^0.10.20",
+        "phpstan/extension-installer": "^1.4",
         "weitzman/drupal-test-traits": "^2.5"
+    },
+    "autoload-dev": {
+        "psr-4": {
+            "Tools\\": "tools/"
+        }
     }
 }

composer.lock

@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "acf7a5349dc6167b6a9c51b2128cd23f",
+    "content-hash": "31d8c2ff0a96c6f09d7d1879afc5ad28",
     "packages": [
         {
             "name": "asm89/stack-cors",
@@ -11656,6 +11656,63 @@
             },
             "time": "2024-03-15T13:55:21+00:00"
         },
+        {
+            "name": "phpat/phpat",
+            "version": "0.10.20",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/carlosas/phpat.git",
+                "reference": "55154db9c36d56aaae5de4bcddb7f5a1202f1910"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/carlosas/phpat/zipball/55154db9c36d56aaae5de4bcddb7f5a1202f1910",
+                "reference": "55154db9c36d56aaae5de4bcddb7f5a1202f1910",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^7.4 || ^8.0",
+                "phpstan/phpstan": "^1.3"
+            },
+            "require-dev": {
+                "friendsofphp/php-cs-fixer": "3.46",
+                "kubawerlos/php-cs-fixer-custom-fixers": "3.18",
+                "phpunit/phpunit": "^9.0 || ^10.0",
+                "vimeo/psalm": "^5.0"
+            },
+            "type": "phpstan-extension",
+            "extra": {
+                "phpstan": {
+                    "includes": [
+                        "extension.neon"
+                    ]
+                }
+            },
+            "autoload": {
+                "files": [
+                    "helpers.php"
+                ],
+                "psr-4": {
+                    "PHPat\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Carlos Alandete Sastre",
+                    "email": "carlos.alandete@gmail.com"
+                }
+            ],
+            "description": "PHP Architecture Tester",
+            "support": {
+                "issues": "https://github.com/carlosas/phpat/issues",
+                "source": "https://github.com/carlosas/phpat/tree/0.10.20"
+            },
+            "time": "2024-11-23T21:56:24+00:00"
+        },
         {
             "name": "phpdocumentor/reflection-common",
             "version": "2.2.0",

phpstan.neon.dist

@@ -3,3 +3,8 @@ parameters:
   paths:
     - modules
     - themes
+    - tools
+services:
+  - class: Tools\Phpat\ArchitectureTest
+    tags:
+      - phpat.test

tools/Phpat/ArchitectureTest.php

@@ -0,0 +1,25 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tools\Phpat;
+
+use PHPat\Selector\Selector;
+use PHPat\Test\Builder\Rule;
+use PHPat\Test\PHPat;
+
+final class ArchitectureTest {
+
+  public function test_classes_should_be_final(): Rule {
+    return PHPat::rule()
+      ->classes(
+        Selector::inNamespace(
+          namespace: '/^Drupal\\\\opd_\w+/',
+          regex: TRUE,
+        ),
+      )
+      ->excluding(Selector::isInterface())
+      ->shouldBeFinal();
+  }
+
+}