diff --git a/src/GeneratedExtensionToMimeTypeMapTest.php b/src/GeneratedExtensionToMimeTypeMapTest.php
index 14fb908..1f26975 100644
--- a/src/GeneratedExtensionToMimeTypeMapTest.php
+++ b/src/GeneratedExtensionToMimeTypeMapTest.php
@@ -68,6 +68,8 @@ public function looking_up_extensions(string $mimeType, array $expectedExtension
         $actual = $map->lookupAllExtensions($mimeType);
 
         // assert
+        sort($expectedExtensions);
+        sort($actual);
         $this->assertEquals($expectedExtensions, $actual);
     }