[10.x] Add the ability to extend the generic types for DatabaseNotifi…

…cationCollection (#47048)

* Add the ability to extend the generic types

* Update DatabaseNotificationCollection.php

* Remove unused

* Add tests

* Fix style

* rm lb

* Updates localtion of type tests

---------

Co-authored-by: Nuno Maduro <enunomaduro@gmail.com>

src/Illuminate/Notifications/DatabaseNotificationCollection.php

@@ -4,6 +4,12 @@
 
 use Illuminate\Database\Eloquent\Collection;
 
+/**
+ * @template TKey of array-key
+ * @template TModel of DatabaseNotification
+ *
+ * @extends \Illuminate\Database\Eloquent\Collection<TKey, TModel>
+ */
 class DatabaseNotificationCollection extends Collection
 {
     /**

types/Notifications/DatabaseNotificationCollection.php

@@ -0,0 +1,25 @@
+<?php
+
+use Illuminate\Notifications\DatabaseNotification;
+use Illuminate\Notifications\DatabaseNotificationCollection;
+
+use function PHPStan\Testing\assertType;
+
+class CustomNotification extends DatabaseNotification
+{
+    //
+}
+
+/**
+ * @extends DatabaseNotificationCollection<int, CustomNotification>
+ */
+class CustomNotificationCollection extends DatabaseNotificationCollection
+{
+    //
+}
+
+$databaseNotificationsCollection = DatabaseNotification::all();
+assertType('Illuminate\Database\Eloquent\Collection<int, Illuminate\Notifications\DatabaseNotification>', $databaseNotificationsCollection);
+
+$customNotificationsCollection = CustomNotification::all();
+assertType('Illuminate\Database\Eloquent\Collection<int, CustomNotification>', $customNotificationsCollection);