outdated poll option for webpack watcher

[dimitriylol]

Describe the bug

The troubleshooting documentation mentions the usage of CHOKIDAR_USEPOLLING=true in case webpack watcher doesn't detect files changes. The latest webpack version (5.72.1) doesn't use chokidar to detect source file changes. It uses its own package watchpack that doesn't support CHOKIDAR_USEPOLLING variable. It has WATCHPACK_POLLING variable for it.

Did you try recovering your dependencies?

Yep, it doesn't change the dependency tree (create-react-app => react-scripts => webpack => watchpack).

Which terms did you search for in User Guide?

N/A

Environment

N/A

Steps to reproduce

N/A

Expected behavior

Updated documentation that mentions WATCHPACK_POLLING in case of troubles with webpack watcher. I'm not sure that CHOKIDAR_USEPOLLING is completely outdated. I found chokidar usage in webpack-dev-server to track public files so I assume they aren't fully migrated from chokidar.

Actual behavior

Setting CHOKIDAR_USEPOLLING variable isn't enough to enforce polling of webpack watcher.

Reproducible demo

I got the problem with webpack watcher during using NFS. Apparently, inotify that fires events on file updates doesn't work with NFS. I couldn't create simple steps to reproduce the issue.

[S-C-Johnston]

@dimitriylol thank you!

Can confirm, as of 2023-06-11 using the latest create-react-app script to init the project, setting WATCHPACK_POLLING=true by some means (direct environment export, .env, whatever) gets the npm start invocation working as expected

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For anyone else coming into this, I also recommend setting in the react-scripts/config/webpack.config.js module.exports to include the object

watchOptions: {
    ignored: ['**/node_modules']
}

so that polling doesn't hammer your cpu with a bunch of files that are not going to change. (https://webpack.js.org/configuration/watch/#watchoptionsignored)