GH-14930: Add test with long filename from custom stream wrapper

Author: joec4i

ext/standard/tests/streams/gh14930.phpt

@@ -0,0 +1,27 @@
+--TEST--
+GH-14930: Custom stream wrapper dir_readdir output truncated to 255 characters in PHP 8.3
+--FILE--
+<?php
+
+class DummyWrapper
+{
+    public $context;
+
+    public function dir_opendir($url, $options)
+    {
+        return true;
+    }
+
+    public function dir_readdir()
+    {
+        return 'very-long-filename-ieNoquiaC6ijeiy9beejaiphoriejo2cheehooGou8uhoh7eh0gefahyuQuohd7eec9auso9eeFah2Maedohsemi1eetoo5fo5biePh5eephai7SiuguipouLeemequ2oope9aigoQu5efak2aLeri9ithaiJ9eew3dianaiHoo1aexaighiitee6geghiequ5nohhiikahwee8ohk2Soip2Aikeithohdeitiedeiku7DiTh2eep3deitiedeiku7DiTh2ee.txt';
+    }
+}
+
+stream_wrapper_register('dummy', DummyWrapper::class);
+
+$dh = opendir('dummy://', stream_context_create());
+var_dump(readdir($dh));
+?>
+--EXPECT--
+string(288) "very-long-filename-ieNoquiaC6ijeiy9beejaiphoriejo2cheehooGou8uhoh7eh0gefahyuQuohd7eec9auso9eeFah2Maedohsemi1eetoo5fo5biePh5eephai7SiuguipouLeemequ2oope9aigoQu5efak2aLeri9ithaiJ9eew3dianaiHoo1aexaighiitee6geghiequ5nohhiikahwee8ohk2Soip2Aikeithohdeitiedeiku7DiTh2eep3deitiedeiku7DiTh2ee.txt"