mocklets/examples/src/isLocalHost/index.js

Reusable standard mocks and fakes for popular browser and Node.js APIs, framework/library objects for Jest

export const isLocalHost = () => {
  if (typeof window === 'undefined') {
    return false;
  }
  
  return ["http://localhost", "http://127.0.0.1"].includes(
    window.location.origin.replace(/\:[\d$]{4,5}/, "")
  ) || Boolean(
    window.location.hostname === 'localhost' ||
    // [::1] is the IPv6 localhost address.
    window.location.hostname === '[::1]' ||
    // 127.0.0.1/8 is considered localhost for IPv4.
    window.location.hostname.match(
      /^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/
    )
  )
};