Fix reading parent attribute

Author: andrewmy

pkg/test/ReadAttributeTrait.php

@@ -2,18 +2,41 @@
 
 namespace Enqueue\Test;
 
+use ReflectionProperty;
+
 trait ReadAttributeTrait
 {
     public function readAttribute(object $object, string $attribute)
     {
-        $refProperty = new \ReflectionProperty(get_class($object), $attribute);
+        $refProperty = $this->getClassAttribute($object, $attribute);
         $refProperty->setAccessible(true);
         $value = $refProperty->getValue($object);
         $refProperty->setAccessible(false);
 
         return $value;
     }
 
+    private function getClassAttribute(
+        object $object,
+        string $attribute,
+        ?string $class = null
+    ): ReflectionProperty {
+        if ($class === null) {
+            $class = get_class($object);
+        }
+
+        try {
+            return new ReflectionProperty($class, $attribute);
+        } catch (\ReflectionException $exception) {
+            $parentClass = get_parent_class($object);
+            if ($parentClass === false) {
+                throw $exception;
+            }
+
+            return $this->getClassAttribute($object, $attribute, $parentClass);
+        }
+    }
+
     private function assertAttributeSame($expected, string $attribute, object $object): void
     {
         static::assertSame($expected, $this->readAttribute($object, $attribute));