Squashed eslint errors

src/index.js

@@ -1,7 +1,8 @@
+/* eslint-disable react/jsx-filename-extension */
 import React from 'react';
 import ReactDOM from 'react-dom';
 import 'bootstrap/dist/css/bootstrap.min.css';
-import App from './App.jsx';
+import App from './App';
 // import * as serviceWorker from './serviceWorker';
 
 ReactDOM.render(<App />, document.getElementById('root'));

src/serviceWorker.js

@@ -1,3 +1,4 @@
+/* eslint-disable no-console */
 // This optional code is used to register a service worker.
 // register() is not called by default.
 
@@ -11,53 +12,20 @@
 // opt-in, read https://bit.ly/CRA-PWA
 
 const isLocalhost = Boolean(
-  window.location.hostname === 'localhost' ||
+  window.location.hostname === 'localhost'
     // [::1] is the IPv6 localhost address.
-    window.location.hostname === '[::1]' ||
+    || window.location.hostname === '[::1]'
     // 127.0.0.0/8 are considered localhost for IPv4.
-    window.location.hostname.match(
-      /^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/
-    )
+    || window.location.hostname.match(
+      /^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/,
+    ),
 );
 
-export function register(config) {
-  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.href);
-    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/facebook/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. Let's check if a service worker still exists or not.
-        checkValidServiceWorker(swUrl, config);
-
-        // Add some additional logging to localhost, pointing developers to the
-        // service worker/PWA documentation.
-        navigator.serviceWorker.ready.then(() => {
-          console.log(
-            'This web app is being served cache-first by a service ' +
-              'worker. To learn more, visit https://bit.ly/CRA-PWA'
-          );
-        });
-      } else {
-        // Is not localhost. Just register service worker
-        registerValidSW(swUrl, config);
-      }
-    });
-  }
-}
-
 function registerValidSW(swUrl, config) {
   navigator.serviceWorker
     .register(swUrl)
-    .then(registration => {
+    .then((registration) => {
+      // eslint-disable-next-line no-param-reassign
       registration.onupdatefound = () => {
         const installingWorker = registration.installing;
         if (installingWorker == null) {
@@ -70,8 +38,8 @@ function registerValidSW(swUrl, config) {
               // but the previous service worker will still serve the older
               // content until all client tabs are closed.
               console.log(
-                'New content is available and will be used when all ' +
-                  'tabs for this page are closed. See https://bit.ly/CRA-PWA.'
+                'New content is available and will be used when all '
+                  + 'tabs for this page are closed. See https://bit.ly/CRA-PWA.',
               );
 
               // Execute callback
@@ -93,25 +61,25 @@ function registerValidSW(swUrl, config) {
         };
       };
     })
-    .catch(error => {
+    .catch((error) => {
       console.error('Error during service worker registration:', error);
     });
 }
 
 function checkValidServiceWorker(swUrl, config) {
   // Check if the service worker can be found. If it can't reload the page.
   fetch(swUrl, {
-    headers: { 'Service-Worker': 'script' }
+    headers: { 'Service-Worker': 'script' },
   })
-    .then(response => {
+    .then((response) => {
       // Ensure service worker exists, and that we really are getting a JS file.
       const contentType = response.headers.get('content-type');
       if (
-        response.status === 404 ||
-        (contentType != null && contentType.indexOf('javascript') === -1)
+        response.status === 404
+        || (contentType != null && contentType.indexOf('javascript') === -1)
       ) {
         // No service worker found. Probably a different app. Reload the page.
-        navigator.serviceWorker.ready.then(registration => {
+        navigator.serviceWorker.ready.then((registration) => {
           registration.unregister().then(() => {
             window.location.reload();
           });
@@ -123,14 +91,48 @@ function checkValidServiceWorker(swUrl, config) {
     })
     .catch(() => {
       console.log(
-        'No internet connection found. App is running in offline mode.'
+        'No internet connection found. App is running in offline mode.',
       );
     });
 }
 
+export function register(config) {
+  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.href);
+    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/facebook/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. Let's check if a service worker still exists or not.
+        checkValidServiceWorker(swUrl, config);
+
+        // Add some additional logging to localhost, pointing developers to the
+        // service worker/PWA documentation.
+        navigator.serviceWorker.ready.then(() => {
+          console.log(
+            'This web app is being served cache-first by a service '
+              + 'worker. To learn more, visit https://bit.ly/CRA-PWA',
+          );
+        });
+      } else {
+        // Is not localhost. Just register service worker
+        registerValidSW(swUrl, config);
+      }
+    });
+  }
+}
+
 export function unregister() {
   if ('serviceWorker' in navigator) {
-    navigator.serviceWorker.ready.then(registration => {
+    navigator.serviceWorker.ready.then((registration) => {
       registration.unregister();
     });
   }