explain

Author: khepin

tests/Definitions/Child.php

@@ -5,6 +5,10 @@
 use Square\Pjson\Json;
 use Square\Pjson\JsonSerialize;
 
+/**
+ * Keep properties in this exact order in this class. We want to confirm valid serialization when serializing `parent`
+ * set that value to `null` but something further down needs to set a nested property there.
+ */
 // phpcs:ignore PSR1.Classes.ClassDeclaration
 class Child
 {

tests/SerializationTest.php

@@ -290,6 +290,8 @@ public function testCollections()
 
     public function testMissingParent()
     {
+        // Ensure that while the `parent` object is null, we can still serialize the parent.id property which is
+        // nested under `parent`.
         $data = new Child();
         $json = '{"identifier":null,"parent":{"id":null}}';