export default function register()

in src/registerServiceWorker.tsx [40:63]

• 16 lines of code
• 6 McCabe index (conditional complexity)

export default function register (toasterSupplier: () => (Toaster | null)) {
  if (process.env.NODE_ENV === 'production' && 'serviceWorker' in navigator) {
    // The URL constructor is available in all browsers that support SW.
    const publicUrl = new URL(process.env.PUBLIC_URL || '', window.location as any as URL)
    if (publicUrl.origin !== window.location.origin) {
      // Our service worker won't work if PUBLIC_URL is on a different origin
      // from what our page is served on. This might happen if a CDN is used to
      // serve assets; see https://github.com/facebookincubator/create-react-app/issues/2374
      return
    }

    window.addEventListener('load', () => {
      const swUrl = `${process.env.PUBLIC_URL}/service-worker.js`

      if (isLocalhost) {
        // This is running on localhost. Lets check if a service worker still exists or not.
        checkValidServiceWorker(swUrl, toasterSupplier)
      } else {
        // Is not local host. Just register service worker
        registerValidSW(swUrl, toasterSupplier)
      }
    })
  }
}