Added post extender with type method, deprecated ConfigurePostTypes (#2101)

src/Extend/Post.php

@@ -0,0 +1,39 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * For detailed copyright and license information, please view the
+ * LICENSE file that was distributed with this source code.
+ */
+
+namespace Flarum\Extend;
+
+use Flarum\Extension\Extension;
+use Flarum\Post\Post as PostModel;
+use Illuminate\Contracts\Container\Container;
+
+class Post implements ExtenderInterface
+{
+    private $postTypes = [];
+
+    /**
+     * Register a new post type. This is generally done for custom 'event posts',
+     * such as those that appear when a discussion is renamed.
+     *
+     * @param string $postType: The ::class attribute of the custom Post type that is being added.
+     */
+    public function type(string $postType)
+    {
+        $this->postTypes[] = $postType;
+
+        return $this;
+    }
+
+    public function extend(Container $container, Extension $extension = null)
+    {
+        foreach ($this->postTypes as $postType) {
+            PostModel::setModel($postType::$type, $postType);
+        }
+    }
+}