test: add fs/promises filehandle stat test

Added test for fs/promises filehandle stat.
PR-URL: #20492
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: Masashi Hirano

test/parallel/test-fs-promises-file-handle-stat.js

@@ -0,0 +1,24 @@
+'use strict';
+
+constcommon=require('../common');
+
+// The following tests validate base functionality for the fs/promises
+// FileHandle.stat method.
+
+const{ open }=require('fs/promises');
+constpath=require('path');
+consttmpdir=require('../common/tmpdir');
+constassert=require('assert');
+
+tmpdir.refresh();
+common.crashOnUnhandledRejection();
+
+asyncfunctionvalidateStat(){
+constfilePath=path.resolve(tmpdir.path,'tmp-read-file.txt');
+constfileHandle=awaitopen(filePath,'w+');
+conststats=awaitfileHandle.stat();
+assert.ok(stats.mtimeinstanceofDate);
+}
+
+validateStat()
+.then(common.mustCall());