Use HttpFoundation

.phpunit-cache/test-results

@@ -1 +1 @@
-{"version":2,"defects":[],"times":{"IndexTest::testHello":0.001}}
+{"version":2,"defects":{"IndexTest::testHelloNoParam":5},"times":{"IndexTest::testHello":0.014,"IndexTest::testHelloNoParam":0}}

index.php

@@ -1,5 +1,14 @@
 <?php
-$name = $_GET['name'] ?? 'poopstink';
+require_once __DIR__.'/vendor/autoload.php';
 
-printf('Hello %s', $name);
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
+
+$request = Request::createFromGlobals();
+
+$name = $request->query->get('name', 'Dingo');
+
+$response = new Response(sprintf('Hello %s', htmlspecialchars($name, ENT_QUOTES, 'UTF-8')));
+
+$response->send();
 

test.php

@@ -13,5 +13,15 @@ class IndexTest extends TestCase
 
         $this->assertEquals('Hello Poopiebutt', $content);
     }
+
+    public function testHelloNoParam(): void
+    {
+        unset($_GET['name']);
+        ob_start();
+        include 'index.php';
+        $content = ob_get_clean();
+
+        $this->assertEquals('Hello Dingo', $content);
+    }
 }