Fix notifications

src/Core/Notifications/Commands/ReadNotificationHandler.php

@@ -6,8 +6,6 @@ use Flarum\Core\Support\DispatchesEvents;
 
 class ReadNotificationHandler
 {
-    use DispatchesEvents;
-
     /**
      * @param ReadNotification $command
      * @return Notification
@@ -26,8 +24,6 @@ class ReadNotificationHandler
         $notification->read();
         $notification->save();
 
-        $this->dispatchEventsFor($notification);
-
         return $notification;
     }
 }

src/Core/Notifications/DiscussionRenamedBlueprint.php

@@ -54,6 +54,6 @@ class DiscussionRenamedBlueprint implements Blueprint
      */
     public static function getSubjectModel()
     {
-        return 'Flarum\Core\Models\Discussion';
+        return 'Flarum\Core\Discussions\Discussion';
     }
 }

src/Core/Notifications/Notification.php

@@ -1,6 +1,7 @@
 <?php namespace Flarum\Core\Notifications;
 
 use Flarum\Core\Model;
+use Flarum\Core\Support\MappedMorphToTrait;
 
 /**
  * Models a notification record in the database.
@@ -20,6 +21,8 @@ use Flarum\Core\Model;
  */
 class Notification extends Model
 {
+    use MappedMorphToTrait;
+
     /**
      * {@inheritdoc}
      */
@@ -111,7 +114,7 @@ class Notification extends Model
      */
     public function subject()
     {
-        return $this->morphTo('subject', 'subjectModel', 'subject_id');
+        return $this->mappedMorphTo(static::$subjectModels, 'subject', 'type', 'subject_id');
     }
 
     /**

src/Core/Support/MappedMorphTo.php

@@ -0,0 +1,43 @@
+<?php namespace Flarum\Core\Support;
+
+use Illuminate\Database\Eloquent\Relations\MorphTo;
+use Illuminate\Database\Eloquent\Builder;
+use Illuminate\Database\Eloquent\Model;
+
+class MappedMorphTo extends MorphTo
+{
+    /**
+     *
+     * @var string
+     */
+    protected $map;
+
+    /**
+     * Create a new morph to relationship instance.
+     *
+     * @param  \Illuminate\Database\Eloquent\Builder  $query
+     * @param  \Illuminate\Database\Eloquent\Model  $parent
+     * @param  string  $foreignKey
+     * @param  string  $otherKey
+     * @param  string  $type
+     * @param  string  $relation
+     * @return void
+     */
+    public function __construct(Builder $query, Model $parent, $foreignKey, $otherKey, $type, $relation, $map)
+    {
+        $this->map = $map;
+
+        parent::__construct($query, $parent, $foreignKey, $otherKey, $type, $relation);
+    }
+
+    /**
+     * Create a new model instance by type.
+     *
+     * @param  string  $type
+     * @return \Illuminate\Database\Eloquent\Model
+     */
+    public function createModelByType($type)
+    {
+        return new $this->map[$type];
+    }
+}

src/Core/Support/MappedMorphToTrait.php

@@ -0,0 +1,48 @@
+<?php namespace Flarum\Core\Support;
+
+trait MappedMorphToTrait
+{
+    public function mappedMorphTo($classes, $name = null, $type = null, $id = null)
+    {
+        // If no name is provided, we will use the backtrace to get the function name
+        // since that is most likely the name of the polymorphic interface. We can
+        // use that to get both the class and foreign key that will be utilized.
+        if (is_null($name)) {
+            list(, $caller) = debug_backtrace(false, 2);
+            $name = snake_case($caller['function']);
+        }
+
+        list($type, $id) = $this->getMorphs($name, $type, $id);
+
+        // If the type value is null it is probably safe to assume we're eager loading
+        // the relationship. When that is the case we will pass in a dummy query as
+        // there are multiple types in the morph and we can't use single queries.
+        if (is_null($typeValue = $this->$type)) {
+            return new MappedMorphTo(
+                $this->newQuery(),
+                $this,
+                $id,
+                null,
+                $type,
+                $name,
+                $classes
+            );
+        } else {
+            // If we are not eager loading the relationship we will essentially treat this
+            // as a belongs-to style relationship since morph-to extends that class and
+            // we will pass in the appropriate values so that it behaves as expected.
+            $class = $classes[$typeValue];
+            $instance = new $class;
+
+            return new MappedMorphTo(
+                $instance->newQuery(),
+                $this,
+                $id,
+                $instance->getKeyName(),
+                $type,
+                $name,
+                $classes
+            );
+        }
+    }
+}

src/Extend/NotificationType.php

@@ -38,7 +38,7 @@ class NotificationType implements ExtenderInterface
         $class = $this->class;
         $type = $class::getType();
 
-        Notification::setSubjectModel($type, $class);
+        Notification::setSubjectModel($type, $class::getSubjectModel());
 
         User::addPreference(User::getNotificationPreferenceKey($type, 'alert'), 'boolval', in_array('alert', $this->enabled));