Policy Extender and Tests (#2461)

Policy application has also been refactored, so that policies return one of `allow`, `deny`, `forceAllow`, `forceDeny`. The result of a set of policies is no longer the first non-null result, but rather the highest priority result (forceDeny > forceAllow > deny > allow, so if a single forceDeny is present, that beats out all other returned results). This removes order in which extensions boot as a factor.

src/Post/Access/PostPolicy.php

@@ -7,39 +7,27 @@
  * LICENSE file that was distributed with this source code.
  */
 
-namespace Flarum\Post;
+namespace Flarum\Post\Access;
 
 use Carbon\Carbon;
+use Flarum\Post\Post;
 use Flarum\Settings\SettingsRepositoryInterface;
-use Flarum\User\AbstractPolicy;
+use Flarum\User\Access\AbstractPolicy;
 use Flarum\User\User;
-use Illuminate\Contracts\Events\Dispatcher;
 
 class PostPolicy extends AbstractPolicy
 {
-    /**
-     * {@inheritdoc}
-     */
-    protected $model = Post::class;
-
     /**
      * @var SettingsRepositoryInterface
      */
     protected $settings;
 
-    /**
-     * @var Dispatcher
-     */
-    protected $events;
-
     /**
      * @param SettingsRepositoryInterface $settings
-     * @param Dispatcher $events
      */
-    public function __construct(SettingsRepositoryInterface $settings, Dispatcher $events)
+    public function __construct(SettingsRepositoryInterface $settings)
     {
         $this->settings = $settings;
-        $this->events = $events;
     }
 
     /**
@@ -51,7 +39,7 @@ class PostPolicy extends AbstractPolicy
     public function can(User $actor, $ability, Post $post)
     {
         if ($actor->can($ability.'Posts', $post->discussion)) {
-            return true;
+            return $this->allow();
         }
     }
 
@@ -71,7 +59,7 @@ class PostPolicy extends AbstractPolicy
             if ($allowEditing === '-1'
                 || ($allowEditing === 'reply' && $post->number >= $post->discussion->last_post_number)
                 || ($post->created_at->diffInMinutes(new Carbon) < $allowEditing)) {
-                return true;
+                return $this->allow();
             }
         }
     }

src/Post/PostServiceProvider.php

@@ -51,9 +51,6 @@ class PostServiceProvider extends AbstractServiceProvider
 
         $this->setPostTypes();
 
-        $events = $this->app->make('events');
-        $events->subscribe(PostPolicy::class);
-
         Post::registerVisibilityScoper(new ScopePostVisibility(), 'view');
     }