Reproduction for Watchpack fs.watch issue on macOS

Quick steps to repro

yarn
node generate
yarn webpack --watch

Detail

To setup the mock data in src run node generate [dirs]. dirs will default to 4096 which is where it starts failing.

This will generate dirs directories each with an index.js with an export which are imported by the main index.js in src.

Then run yarn webpack --watch. It should build and then start failing with:

[webpack-cli] watching files for updates...
Watchpack Error (watcher): Error: EMFILE: too many open files, watch
Watchpack Error (watcher): Error: EMFILE: too many open files, watch
Watchpack Error (watcher): Error: EMFILE: too many open files, watch
Watchpack Error (watcher): Error: EMFILE: too many open files, watch