setup phpunit for testing

tests/Controller/UserControllerTest.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace App\Tests\Controller;
+
+use App\Repository\UserRepository;
+use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;
+
+class UserControllerTest extends WebTestCase
+{
+    public function testUserPage(): void
+    {
+        $client = static::createClient();
+        $userRepository = static::$container->get(UserRepository::class);
+
+        $client->catchExceptions(false);
+
+        // retrieve the test user
+        $testUser = $userRepository->findOneByEmail('jannis@thisfro.ch');
+
+        // simulate $testUser being logged in
+        $client->loginUser($testUser);
+
+        // test e.g. the profile page
+        $client->request('GET', '/user');
+        $this->assertResponseIsSuccessful();
+        $this->assertSelectorTextContains('h1', 'Hello thisfro!');
+    }
+}