Function updateNotifier

deps/npm/lib/cli/update-notifier.js:69–98

(npm, spec = '*')

}

const updateNotifier = async (npm, spec = '*') => {
  // if we're on a prerelease train, then updates are coming fast check for a new one daily.
  // otherwise, weekly.
  const { version } = npm
  const current = parse(version)

  // if we're on a beta train, always get the next beta
  if (current.prerelease.length) {
    spec = `^${version}`
  }

  // while on a beta train, get updates daily
  const duration = current.prerelease.length ? DAILY : WEEKLY

  const t = new Date(Date.now() - duration)
  // if we don't have a file, then definitely check it.
  const st = await stat(lastCheckedFile(npm)).catch(() => ({ mtime: t - 1 }))

  // if we've already checked within the specified duration, don't check again
  if (!(t > st.mtime)) {
    return null
  }

  // intentional.  do not await this.  it's a best-effort update.
  // if this fails, it's ok.
  // might be using /dev/null as the cache or something weird like that.
  writeFile(lastCheckedFile(npm), '').catch(() => {})

  return updateCheck(npm, spec, version, current)
}

module.exports = async npm => {
  if (