myapp/node_modules/pacote/lib/util/cache-dir.js

const { resolve } = require('node:path')
const { tmpdir, homedir } = require('node:os')

module.exports = (fakePlatform = false) => {
  const temp = tmpdir()
  const uidOrPid = process.getuid ? process.getuid() : process.pid
  const home = homedir() || resolve(temp, 'npm-' + uidOrPid)
  const platform = fakePlatform || process.platform
  const cacheExtra = platform === 'win32' ? 'npm-cache' : '.npm'
  const cacheRoot = (platform === 'win32' && process.env.LOCALAPPDATA) || home
  return {
    cacache: resolve(cacheRoot, cacheExtra, '_cacache'),
    tufcache: resolve(cacheRoot, cacheExtra, '_tuf'),
  }
}