watch: batch file restarts

Co-authored-by: Matthieu <matthieusieben@users.noreply.github.com>
PR-URL: #51992
Reviewed-By: Nitzan Uziely <linkgoron@gmail.com>
Reviewed-By: Chemi Atlow <chemi@atlow.co.il>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>

Author: MoLow

lib/internal/main/watch_mode.js

@@ -26,7 +26,7 @@ const { spawn } = require('child_process');
 const { inspect } = require('util');
 const { setTimeout, clearTimeout } = require('timers');
 const { resolve } = require('path');
-const { once, on } = require('events');
+const { once } = require('events');
 
 prepareMainThreadExecution(false, false);
 markBootstrapComplete();
@@ -103,27 +103,28 @@ async function stop() {
   clearGraceReport();
 }
 
+let restarting = false;
 async function restart() {
-  if (!kPreserveOutput) process.stdout.write(clear);
-  process.stdout.write(`${green}Restarting ${kCommandStr}${white}\n`);
-  await stop();
-  start();
-}
-
-(async () => {
-  emitExperimentalWarning('Watch mode');
-
+  if (restarting) return;
+  restarting = true;
   try {
+    if (!kPreserveOutput) process.stdout.write(clear);
+    process.stdout.write(`${green}Restarting ${kCommandStr}${white}\n`);
+    await stop();
     start();
+  } finally {
+    restarting = false;
+  }
+}
 
-    // eslint-disable-next-line no-unused-vars
-    for await (const _ of on(watcher, 'changed')) {
-      await restart();
-    }
-  } catch (error) {
+emitExperimentalWarning('Watch mode');
+start();
+watcher
+  .on('changed', restart)
+  .on('error', (error) => {
+    watcher.off('changed', restart);
     triggerUncaughtException(error, true /* fromPromise */);
-  }
-})();
+  });
 
 // Exiting gracefully to avoid stdout/stderr getting written after
 // parent process is killed.

lib/internal/watch_mode/files_watcher.js

@@ -32,7 +32,7 @@ class FilesWatcher extends EventEmitter {
   #signal;
 
   constructor({ debounce = 200, mode = 'filter', signal } = kEmptyObject) {
-    super();
+    super({ __proto__: null, captureRejections: true });
 
     validateNumber(debounce, 'options.debounce', 0, TIMEOUT_MAX);
     validateOneOf(mode, 'options.mode', ['filter', 'all']);