diff --git a/tests/Util/yaml_fixtures/add_item_to_array_after_array.test b/tests/Util/yaml_fixtures/add_item_to_array_after_array.test
new file mode 100644
index 000000000..da96aebb9
--- /dev/null
+++ b/tests/Util/yaml_fixtures/add_item_to_array_after_array.test
@@ -0,0 +1,12 @@
+framework:
+    messenger:
+        routing:
+            App\Messages\OldMessage: [ transport1, transport2 ]
+===
+$data['framework']['messenger']['routing']['App\Messages\NewMessage'] = 'async';
+===
+framework:
+    messenger:
+        routing:
+            App\Messages\OldMessage: [ transport1, transport2 ]
+            App\Messages\NewMessage: async