JSON decode empty [] test

Author: FabioBatSilva

php/tests/json_encode_test.php

@@ -0,0 +1,16 @@
+<?php
+
+require_once (dirname(__DIR__) . '/vendor/autoload.php');
+require_once (__DIR__ . '/test_util.php');
+
+use Foo\TestMessage;
+
+$message = new TestMessage();
+$values = array_filter([
+    'true_optional_string' => null,
+]);
+
+$message->mergeFromJsonString(json_encode($values));
+//$message->mergeFromJsonString('[]');
+
+var_dump($message->hasTrueOptionalString());