Fix json serialization of UncontrolledSubject

Author: danmichaelo

src/Fields/UncontrolledSubject.php

@@ -2,13 +2,8 @@
 
 namespace Scriptotek\Marc\Fields;
 
-class UncontrolledSubject extends Subfield implements SubjectInterface
+class UncontrolledSubject extends Subfield implements SubjectInterface, \JsonSerializable
 {
-    /**
-     * @var array List of properties to be included when serializing the record using the `toArray()` method.
-     */
-    public $properties = ['type', 'vocabulary', 'term', 'id'];
-
     public function getType()
     {
         return Subject::UNCONTROLLED_INDEX_TERM;
@@ -41,4 +36,13 @@ public function __toString()
     {
         return $this->getTerm();
     }
+
+    public function jsonSerialize()
+    {
+        return [
+            'type' => $this->getType(),
+            'term' => $this->getTerm(),
+        ];
+    }
+
 }

tests/data/examples/bibliographic2.json

@@ -36,8 +36,17 @@
             "vocabulary": "tekord",
             "term": "Optiske instrumenter"
         },
-        "akustooptiske",
-        "effekter",
-        "komponenter"
+        {
+            "type": "653",
+            "term": "akustooptiske"
+        },
+        {
+            "type": "653",
+            "term": "effekter"
+        },
+        {
+            "type": "653",
+            "term": "komponenter"
+        }
     ]
-}
+}