function shouldRequireUrl (url) {
  return (
    // an absolute url and it is not `windows` path like `C:\dir\file`:
    (absoluteUrlRE.test(url) === true && path.win32.isAbsolute(url) === false)
    // a protocol-relative:
    || protocolRelativeRE.test(url) === true
    // some kind of url for a template:
    || templateUrlRE.test(url) === true
    // not a request if root isn't set and it's a root-relative url
    || rootRelativeUrlRE.test(url) === true
  ) === false
}
Inspired by loader-utils > isUrlRequest()
Mimics Webpack v4 & css-loader v3 behavior