Use fs.watch instead of chokidar if Node.js >=v19.1

[gajus]

Describe the bug

File changes are not being detected when multiple instances of chokidar are running in the directory.

When using Turbowatch (which used to default to chokidar) and Vite together, Vite's HMR would just stop working.

Change watching method to polling fixes the issue, but mixes CPU go brrrrrrrr.

As far as I can tell, it is due to this issue paulmillr/chokidar#1240

For what it is worth, Turbowatch was also updated to use the suggested logic.

gajus/turbowatch#22

Theoretically Vite could just use Turbowatch to implement watching.

Reproduction

N/A

Steps to reproduce

N/A

System Info

N/A

Used Package Manager

npm

Logs

No response

Validations

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[silverwind]

How is fs.watch these days? Chokidar was specifically created because of the shortcomings mentioned in its README, have these been resolved?

Generally I'm for trying it because it removes the pain that is fsevents.

[gajus]

Doesn't report filenames on MacOS.

No longer a problem.

Doesn't report events at all when using editors like Sublime on MacOS.

Cannot replicate.

Often reports events twice.

True.

Emits most changes as rename.

True.

Does not provide an easy way to recursively watch file trees.

No longer true, as of Node.js v19.1

Does not support recursive watching on Linux.

No longer true, as of Node.js v19.1

[silverwind]

Often reports events twice.
True.

Can and should be worked around via debounce or better, a shared interval that batches events together.

Emits most changes as rename.
True.

Probably does not matter in context of vite's usage.

[gajus]

Indeed.

[gajus]

@silverwind This might be useful vercel/turbo#986 (comment)

[snnsnn]

Often reports events twice.

This is a common misconception among Node users. NodeJS does not fire multiple events for a single change, it is the editor updates the file multiple times. Checkout the link for details.

• https://stackoverflow.com/a/75149864/7134134

If fs watch is not enough, best alternative would be parcel watcher which powers vscode:

• https://github.com/parcel-bundler/watcher
• https://code.visualstudio.com/updates/v1_62#_engineering

[gajus]

Parcel watcher implements the same backends that Turbowatch does:

@parcel/watcher has the following watcher backends, listed in priority order:

• FSEvents on macOS
• Watchman if installed
• fts (brute force) on Linux
• FindFirstFile (brute force) on Windows

[bluwy]

Closing this to continue the conversation at #13593. We have also discussed using fs.watch, but it is a bit low level that we would have to eventually re-implement a chokidar-like interface to be able to nicely use it. So if we're switching away from chokidar, it would likely be @parcel/watcher