Add scratch using parameter/response refs (zircote#1537)

tests/Fixtures/Scratch/UsingRefs.php

@@ -0,0 +1,33 @@
+<?php declare(strict_types=1);
+
+/**
+ * @license Apache 2.0
+ */
+
+namespace OpenApi\Tests\Fixtures\Scratch;
+
+use OpenApi\Attributes as OAT;
+
+#[OAT\PathParameter(name: 'itemName', description: 'The item name')]
+class UsingRefsParameter
+{
+}
+
+#[OAT\Response(response: 'item', description: 'Item response')]
+class UsingRefsResponse
+{
+}
+
+#[OAT\Info(title: 'Parameter Ref', version: '1.0.0')]
+#[OAT\Get(
+    path: '/item/{item_name}',
+    parameters: [
+        new OAT\Parameter(ref: '#/components/parameters/itemName'),
+    ],
+    responses: [
+        new OAT\Response(response: 200, ref: '#/components/responses/item'),
+    ]
+)]
+class UsingRefsController
+{
+}

tests/Fixtures/Scratch/UsingRefs.yaml

@@ -0,0 +1,23 @@
+openapi: 3.0.0
+info:
+  title: 'Parameter Ref'
+  version: 1.0.0
+paths:
+  '/item/{item_name}':
+    get:
+      operationId: 6ecb3788642c6ba8ce8d99cbcd554dbe
+      parameters:
+        -
+          $ref: '#/components/parameters/itemName'
+      responses:
+        '200':
+          $ref: '#/components/responses/item'
+components:
+  responses:
+    item:
+      description: 'Item response'
+  parameters:
+    itemName:
+      name: itemName
+      in: path
+      description: 'The item name'