Try to catch unhandled exception (#19360)

app/javascript/packs/hideBookmarkButtons.js

@@ -1,6 +1,6 @@
-import { getUserDataAndCsrfToken } from '@utilities/getUserDataAndCsrfToken';
+import { getUserDataAndCsrfTokenSafely } from '@utilities/getUserDataAndCsrfToken';
 
-getUserDataAndCsrfToken().then(({ currentUser }) => {
+getUserDataAndCsrfTokenSafely().then(({ currentUser }) => {
   const currentUserId = currentUser && currentUser.id;
 
   document.querySelectorAll('.bookmark-button').forEach((button) => {

app/javascript/utilities/__tests__/getUserDataAndCsrfToken.test.js

@@ -1,4 +1,7 @@
-import { getUserDataAndCsrfToken } from '../getUserDataAndCsrfToken';
+import {
+  getUserDataAndCsrfToken,
+  getUserDataAndCsrfTokenSafely,
+} from '../getUserDataAndCsrfToken';
 
 const ERROR_MESSAGE = "Couldn't find user data on page.";
 
@@ -54,3 +57,16 @@ describe('getUserDataAndCsrfToken', () => {
     });
   });
 });
+
+describe('getUserDataAndCsrfTokenSafely', () => {
+  afterEach(() => {
+    document.head.innerHTML = '';
+    document.body.removeAttribute('data-user');
+  });
+
+  test('should not reject if no user or csrf token found.', async () => {
+    await expect(getUserDataAndCsrfTokenSafely(document)).resolves.toEqual(
+      expect.anything(),
+    );
+  });
+});

app/javascript/utilities/getUserDataAndCsrfToken.js

@@ -4,13 +4,23 @@ export function getCsrfToken() {
   return element !== null ? element.content : undefined;
 }
 
-const getWaitOnUserDataHandler = ({ resolve, reject, waitTime = 20 }) => {
+const getWaitOnUserDataHandler = ({
+  resolve,
+  reject,
+  safe = false,
+  waitTime = 20,
+}) => {
   let totalTimeWaiting = 0;
 
   return function waitingOnUserData() {
     if (totalTimeWaiting === 3000) {
-      reject(new Error("Couldn't find user data on page."));
-      return;
+      if (!safe) {
+        reject(new Error("Couldn't find user data on page."));
+        return;
+      } 
+        resolve({ user, csrfToken });
+        return;
+      
     }
 
     const csrfToken = getCsrfToken(document);
@@ -28,6 +38,13 @@ const getWaitOnUserDataHandler = ({ resolve, reject, waitTime = 20 }) => {
   };
 };
 
+export function getUserDataAndCsrfTokenSafely() {
+  return new Promise((resolve, reject) => {
+    const safe = true;
+    getWaitOnUserDataHandler({ resolve, reject, safe })();
+  });
+}
+
 export function getUserDataAndCsrfToken() {
   return new Promise((resolve, reject) => {
     getWaitOnUserDataHandler({ resolve, reject })();