test: fix test-watch-mode

Refs: #44898
PR-URL: #45585
Reviewed-By: Moshe Atlow <moshe@atlow.co.il>
Reviewed-By: Erick Wendel <erick.workspace@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

Author: StefanStojanovic

test/sequential/test-watch-mode.mjs

@@ -15,11 +15,16 @@ if (common.isIBMi)
 common.skip('IBMi does not support `fs.watch()`');
 
 constsupportsRecursive=common.isOSX||common.isWindows;
+letdisableRestart=false;
 
 functionrestart(file){
 // To avoid flakiness, we save the file repeatedly until test is done
 writeFileSync(file,readFileSync(file));
-consttimer=setInterval(()=>writeFileSync(file,readFileSync(file)),1000);
+consttimer=setInterval(()=>{
+if(!disableRestart){
+writeFileSync(file,readFileSync(file));
+}
+},common.platformTimeout(1000));
 return()=>clearInterval(timer);
 }
 
@@ -38,11 +43,15 @@ async function spawnWithRestarts({
 letstdout='';
 letcancelRestarts;
 
+disableRestart=true;
 constchild=spawn(execPath,['--watch','--no-warnings', ...args],{encoding: 'utf8'});
 child.stderr.on('data',(data)=>{
 stderr+=data;
 });
 child.stdout.on('data',async(data)=>{
+if(data.toString().includes('Restarting')){
+disableRestart=true;
+}
 stdout+=data;
 constrestartsCount=stdout.match(newRegExp(`Restarting ${printedArgs.replace(/\\/g,'\\\\')}`,'g'))?.length??0;
 if(restarts===0||!isReady(data.toString())){
@@ -54,6 +63,9 @@ async function spawnWithRestarts({
 return;
 }
 cancelRestarts??=restart(watchedFile);
+if(isReady(data.toString())){
+disableRestart=false;
+}
 });
 
 awaitonce(child,'exit');
@@ -97,9 +109,9 @@ async function failWriteSucceed({ file, watchedFile }) {
 
 tmpdir.refresh();
 
-// Warning: this suite can run safely with concurrency: true
-// only if tests do not watch/depend on the same files
-describe('watch mode',{concurrency: true,timeout: 60_000},()=>{
+// Warning: this suite cannot run safely with concurrency: true
+// because of the disableRestart flag used for controlling restarts
+describe('watch mode',{concurrency: false,timeout: 60_000},()=>{
 it('should watch changes to a file - event loop ended',async()=>{
 constfile=createTmpFile();
 const{ stderr, stdout }=awaitspawnWithRestarts({ file });