nodejs: remove empty directories recursively

cleanupEmptyFolders.js

import { readdirSync, rmdirSync, statSync } from 'node:fs'
import { join } from 'node:path'

export const cleanupEmptyFolders = (folder) => {
  if (!statSync(folder).isDirectory()) return
  let files = readdirSync(folder)

  if (files.length > 0) {
    files.forEach((file) => cleanupEmptyFolders(join(folder, file)))
    // Re-evaluate files; after deleting subfolders we may have an empty parent
    // folder now.
    files = readdirSync(folder)
  }

  if (files.length == 0) {
    console.log('removing: ', folder)
    rmdirSync(folder)
  }
}

Very nice. In case anyone needs a version which excludes certain directories from the traversal (such as the ubiquitous node_modules/ directory), here is a slight revision I made -- this should work for Typescript/Node:
https://gist.github.com/rnag/a5e8dcea68979a5df4a946e41f75ea97

Measuring performance, I noted a huge improvement in my case. ~100 milliseconds down to ~1 millisecond. The reason is that otherwise it was traversing down a node_modules subfolder which had a ton of folders underneath it that it need to separately check.