adds JSON_ERROR_NON_BACKED_ENUM to allowed JSON::encode() errors.

src/Util/JSON.php

@@ -35,6 +35,9 @@ public static function encode($data, int $options = 0, int $maxDepth = 512): str
         $encodedData = json_encode($data, $options, $maxDepth);
 
         $allowedErrors = [\JSON_ERROR_NONE, \JSON_ERROR_RECURSION, \JSON_ERROR_INF_OR_NAN, \JSON_ERROR_UNSUPPORTED_TYPE];
+        if (\defined('JSON_ERROR_NON_BACKED_ENUM')) {
+            $allowedErrors[] = \JSON_ERROR_NON_BACKED_ENUM;
+        }
 
         $encounteredAnyError = json_last_error() !== \JSON_ERROR_NONE;
 

tests/Util/Fixtures/NonBackedEnum.php

@@ -0,0 +1,9 @@
+<?php declare(strict_types=1);
+
+namespace Sentry\Tests\Util\Fixtures;
+
+enum NonBackedEnum
+{
+    case None;
+    case Some;
+}

tests/Util/JSONTest.php

@@ -7,6 +7,7 @@
 use PHPUnit\Framework\TestCase;
 use Sentry\Exception\JsonException;
 use Sentry\Tests\Util\Fixtures\JsonSerializableClass;
+use Sentry\Tests\Util\Fixtures\NonBackedEnum;
 use Sentry\Tests\Util\Fixtures\SimpleClass;
 use Sentry\Util\JSON;
 
@@ -143,6 +144,17 @@ public function testEncodeRespectsOptionsArgument(): void
         $this->assertSame('{}', JSON::encode([], \JSON_FORCE_OBJECT));
     }
 
+    /**
+     * The `JSON_ERROR_NON_BACKED_ENUM` constant is only exposed from 8.1.5 and up.
+     *
+     * @requires PHP >= 8.1.5
+     */
+    public function testEncodeGracefullyHandlesUnitEnums(): void
+    {
+        $result = JSON::encode([NonBackedEnum::None, NonBackedEnum::Some]);
+        $this->assertSame('[0,0]', $result);
+    }
+
     /**
      * @dataProvider decodeDataProvider
      */