test_runner: fix test runner watch mode when no positional arguments

PR-URL: #49578Fixes: #49617
Reviewed-By: Chemi Atlow <chemi@atlow.co.il>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>

Author: MoLow

src/node_options.cc

@@ -173,7 +173,7 @@ void EnvironmentOptions::CheckOptions(std::vector<std::string>* errors,
  } elseif (force_repl) {
  errors->push_back("either --watch or --interactive "
 "can be used, not both");
- } elseif (argv->size() < 1 || (*argv)[1].empty()) {
+ } elseif (!test_runner && (argv->size() < 1 || (*argv)[1].empty())) {
  errors->push_back("--watch requires specifying a file");
  }
 

test/parallel/test-runner-watch-mode.mjs

@@ -17,7 +17,7 @@ tmpdir.refresh();
 constfixtureContent={
 'dependency.js': 'module.exports = {};',
 'dependency.mjs': 'export const a = 1;',
-'dependent.js': `
+'test.js': `
 const test = require('node:test');
 require('./dependency.js');
 import('./dependency.mjs');
@@ -29,12 +29,12 @@ const fixturePaths = Object.keys(fixtureContent)
 Object.entries(fixtureContent)
 .forEach(([file,content])=>writeFileSync(fixturePaths[file],content));
 
-asyncfunctiontestWatch({ fileToUpdate }){
+asyncfunctiontestWatch({ fileToUpdate, file}){
 constran1=util.createDeferredPromise();
 constran2=util.createDeferredPromise();
 constchild=spawn(process.execPath,
-['--watch','--test','--no-warnings',fixturePaths['dependent.js']],
-{encoding: 'utf8',stdio: 'pipe'});
+['--watch','--test',file ? fixturePaths[file] : undefined].filter(Boolean),
+{encoding: 'utf8',stdio: 'pipe',cwd: tmpdir.path});
 letstdout='';
 
 child.stdout.on('data',(data)=>{
@@ -47,25 +47,26 @@ async function testWatch({ fileToUpdate }) {
 awaitran1.promise;
 constcontent=fixtureContent[fileToUpdate];
 constpath=fixturePaths[fileToUpdate];
-constinterval=setInterval(()=>{
-console.log(`Updating ${path}`);
-writeFileSync(path,content);
-},50);
+constinterval=setInterval(()=>writeFileSync(path,content),common.platformTimeout(1000));
 awaitran2.promise;
 clearInterval(interval);
 child.kill();
 }
 
 describe('test runner watch mode',()=>{
 it('should run tests repeatedly',async()=>{
-awaittestWatch({fileToUpdate: 'dependent.js'});
+awaittestWatch({file: 'test.js',fileToUpdate: 'test.js'});
 });
 
 it('should run tests with dependency repeatedly',async()=>{
-awaittestWatch({fileToUpdate: 'dependency.js'});
+awaittestWatch({file: 'test.js',fileToUpdate: 'dependency.js'});
 });
 
 it('should run tests with ESM dependency',async()=>{
-awaittestWatch({fileToUpdate: 'dependency.mjs'});
+awaittestWatch({file: 'test.js',fileToUpdate: 'dependency.mjs'});
+});
+
+it('should support running tests without a file',async()=>{
+awaittestWatch({fileToUpdate: 'test.js'});
 });
 });