Add an ignore/exclude option to --watch (fixes infinite restart loop when a watched process writes+imports a file, e.g. Vite createServer)

Inizia dal punto di ingresso node --watch ed esegui la riproduzione minima di Vite con createServer() per osservare il ciclo di riavvio. Determina la semantica supportata per exclude o ignore, quindi verifica che le opzioni glob ripetibili impediscano ai file generati o temporanei di attivare riavvii, mentre le modifiche ai file sorgente continuino ad attivarli.

What is the problem this feature will solve?

node --watch enters an infinite restart loop when the watched process itself writes a file and then dynamically imports it during startup. The watcher adds the freshly-written, now-imported file to its watch set, sees it as "changed," and restarts — which re-runs the same write-and-import, restarting again, forever.

The most common real-world trigger is starting a Vite dev server in middleware mode under node --watch: Vite's config loader writes a temporary config file and await import()s it during createServer(). There is currently no way to exclude that file (or node_modules, or any generated/temp path) from --watch, so the loop cannot be worked around with native flags.

Today node --watch only offers --watch, --watch-path, and --watch-preserve-output. There is no ignore/exclude option. (#45467 is the inverse request — adding paths to watch.)

Minimal reproduction

In any project with vite installed, create repro.mts:

import { createServer } from "vite";
const v = await createServer({ appType: "custom", server: { middlewareMode: true } });
console.log("VITE_UP", typeof v.middlewares);
setInterval(() => {}, 1000);

Run:

node --watch repro.mts

Observed

VITE_UP function
Restarting 'repro.mts'
VITE_UP function
Restarting 'repro.mts'
... (repeats indefinitely)

Reproduced on every version tested (darwin arm64), ~34–35 Restarting cycles in ~15 seconds:

Expected

The process boots once and stays up until a source file the developer actually edits changes — i.e. files written and imported by the process itself during startup should not be able to trigger a restart, or there should be a way to exclude them.

Root cause

Per the analysis in vitejs/vite#19854, Vite's config loading writes a temp file and immediately dynamic-imports it (return (await import(pathToFileURL(tempFileName).href)).default). Inserting a delay between the write and the import stops the loop, confirming a race between the process's own write+import and --watch's file monitoring. Because --watch watches every imported file and has no exclude mechanism, the generated file becomes a restart trigger.

What is the feature you are proposing to solve the problem?

An ignore/exclude option for watch mode, e.g.:

node --watch --watch-exclude='**/node_modules/**' --watch-exclude='**/.vite-temp-*' app.mts

(name/spelling open — --watch-exclude or --watch-ignore, glob-based, repeatable). This would let developers exclude node_modules, build caches, and temp/generated files from triggering restarts, which resolves this loop and matches what every userland watcher (nodemon, tsx, chokidar-based tools) already provides.

Optionally/additionally: do not let files written by the watched process after startup began count as external changes for the initial run.

What alternatives have you considered?

• --watch-path — scopes what is watched but cannot exclude a sub-path or generated file from an otherwise-watched tree, so it doesn't fix this.
• Userland watchers (tsx watch, nodemon) — these do not loop on the identical reproduction because they watch only the static import graph and/or support ignore globs. This is the gap relative to native --watch.

Related issues / downstream reports

• vitejs/vite#19854 — Node --watch + createServer() infinite reload loop (closed as "not planned"; no determination of whether it's a Vite or Node issue).
• nubjs/nub#204 — same loop via nub watch, which wraps Node's native --watch (identical Restarting '<file>' output).