fix(tracking): remove navigator.sendBeacon .bind and add try/catch

Simplifies the `navigator.sendBeacon` call to avoid scoping shenanigans, and adds a `try`/`catch` if all else fails.

Author: Josh Goldberg

packages/tracking/src/events/__tests__/track.test.ts

@@ -126,6 +126,24 @@ describe('createTracker', () => {
           { body: expect.any(FormData), method: 'POST' }
         );
       });
+
+      it('calls to fetch when beacon throws an error', () => {
+        Object.defineProperty(navigator, 'sendBeacon', {
+          writable: true,
+          value: () => {
+            throw new Error('Oh no!');
+          },
+        });
+
+        tracker[event](expectedProps);
+
+        expect(
+          fetch
+        ).toHaveBeenCalledWith(
+          'https://www.codecademy.com/analytics/user?utm_source=twitter',
+          { body: expect.any(FormData), method: 'POST' }
+        );
+      });
     });
   };
 

packages/tracking/src/events/track.ts

@@ -23,14 +23,16 @@ export const createTracker = ({ apiBaseUrl, verbose }: TrackerOptions) => {
       form.append(k, v.toString());
     }
 
-    // Firefox allows users to disable navigator.sendBeacon, and very old Safari versions don't have it.
-    const sendBeacon =
+    try {
+      // Firefox allows users to disable navigator.sendBeacon, and very old Safari versions don't have it.
       // [WEB-1700]: Additionally, Chrome 79-80 gives "Illegal invocation" with ?., so through 2022 we should support them.
       // It seems similar to this: https://github.com/vercel/next.js/issues/23856
       // eslint-disable-next-line @typescript-eslint/prefer-optional-chain
-      navigator.sendBeacon && navigator.sendBeacon.bind(navigator);
-    if (sendBeacon?.(uri, form)) {
-      return;
+      if (navigator.sendBeacon && navigator.sendBeacon(uri, form)) {
+        return;
+      }
+    } catch {
+      // Even with the proper scoping, Chrome 79-80 still gives "Illegal invocation" crashes. Sigh.
     }
 
     // Either way, we fall back to standard fetch if sendBeacon fails.