additional tests for api controllers (#1433)

* added CreatePostControllerTest

* added DeleteDiscussionControllerTest

* added ListDiscussionControllerTest

* added TokenControllerTest

* minor improvement to policy, no need for Carbon object there, added ShowDiscussionControllerTest

* added showDiscussionControllerTest but cant make Guests view the discussion created by a user

* viewing for guests tested, we might need factories

framework/core/tests/Test/Concerns/ManagesContent.php

@@ -0,0 +1,45 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * (c) Toby Zerner <toby.zerner@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Flarum\Tests\Test\Concerns;
+
+use Flarum\Post\CommentPost;
+use Flarum\Post\Event\Posted;
+
+trait ManagesContent
+{
+    use RetrievesAuthorizedUsers;
+
+    protected function addPostByNormalUser(): CommentPost
+    {
+        $actor = $this->getNormalUser();
+
+        $post = CommentPost::reply(
+            $this->discussion->id,
+            'a normal reply - too-obscure',
+            $actor->id,
+            '127.0.0.1'
+        );
+
+        $post->save();
+
+        if (! $this->discussion->startPost) {
+            $this->discussion->setStartPost($post);
+            $this->discussion->setLastPost($post);
+
+            $this->discussion->save();
+
+            event(new Posted($post, $actor));
+        }
+
+        return $post;
+    }
+}

framework/core/tests/Test/Concerns/RetrievesAuthorizedUsers.php

@@ -21,12 +21,12 @@ trait RetrievesAuthorizedUsers
         'email' => 'normal@machine.local'
     ];
 
-    public function getAdminUser()
+    public function getAdminUser(): User
     {
         return User::find(1);
     }
 
-    public function getNormalUser()
+    public function getNormalUser(): User
     {
         return User::unguarded(function () {
             return User::firstOrCreate([