test: make fs watch test more stable

PR-URL: #41715 Reviewed-By: Rich Trott <[email protected]> Reviewed-By: Colin Ihrig <[email protected]> Reviewed-By: Richard Lau <[email protected]> Reviewed-By: Luigi Pinca <[email protected]> Reviewed-By: James M Snell <[email protected]>

Author: benjamingr

test/pummel/test-fs-watch-non-recursive.js

@@ -28,7 +28,7 @@ if (common.isIBMi){
 
 constpath=require('path');
 constfs=require('fs');
-
+constassert=require('assert');
 consttmpdir=require('../common/tmpdir');
 tmpdir.refresh();
 
@@ -38,13 +38,14 @@ const filepath = path.join(testsubdir, 'watch.txt');
 
 fs.mkdirSync(testsubdir,0o700);
 
-// Need a grace period, else the mkdirSync() above fires off an event.
-setTimeout(function(){
-constwatcher=fs.watch(testDir,{persistent: true},common.mustNotCall());
-setTimeout(function(){
-fs.writeFileSync(filepath,'test');
-},100);
-setTimeout(function(){
-watcher.close();
-},500);
-},50);
+constwatcher=fs.watch(testDir,{persistent: true},(event,filename)=>{
+// This function may be called with the directory depending on timing but
+// must not be called with the file..
+assert.strictEqual(filename,'testsubdir');
+});
+setTimeout(()=>{
+fs.writeFileSync(filepath,'test');
+},100);
+setTimeout(()=>{
+watcher.close();
+},500);