Address PR comments

Author: hsubox76

packages-exp/app-check-exp/src/internal-api.test.ts

@@ -215,7 +215,7 @@ describe('internal api', () => {
       });
     });
 
-    it('calls optional error handler if there is an error getting a token', async () => {
+    it('calls 3P error handler if there is an error getting a token', async () => {
       const appCheck = initializeAppCheck(app, {
         provider: new ReCaptchaV3Provider(FAKE_SITE_KEY),
         isTokenAutoRefreshEnabled: true
@@ -227,7 +227,7 @@ describe('internal api', () => {
 
       addTokenListener(
         appCheck as AppCheckService,
-        ListenerType['2P'],
+        ListenerType['3P'],
         listener1,
         errorFn1
       );

packages-exp/app-check-exp/src/internal-api.ts

@@ -284,24 +284,19 @@ function notifyTokenListeners(
 
   for (const observer of observers) {
     try {
-      if (observer.error) {
-        // If this listener has an error handler, handle errors differently
-        // from successes.
-        if (token.error) {
-          observer.error(token.error);
-        } else {
-          observer.next(token);
-        }
+      if (observer.type === ListenerType['3P'] && token.error != null) {
+        // If this listener was added by a 3P call, send any token error to
+        // the supplied error handler. A 3P observer always has an error
+        // handler.
+        observer.error!(token.error);
       } else {
+        // If the token has no error field, always return the token.
         // If this is a 2P listener, return the token, whether or not it
-        // has an error field. If it is a 3P listener with no error handler,
-        // ignore the error.
-        if (observer.type === ListenerType['2P']) {
-          observer.next(token);
-        }
+        // has an error field.
+        observer.next(token);
       }
     } catch (e) {
-      // If any handler fails, ignore and run next handler.
+      // Errors in the listener function itself are always ignored.
     }
   }
 }

packages-exp/app-check-exp/src/types.ts

@@ -41,7 +41,7 @@ export interface AppCheckTokenObserver
   type: ListenerType;
 }
 
-export enum ListenerType {
+export const enum ListenerType {
   '2P' = '2P',
   '3P' = '3P'
 }

packages-exp/app-check-exp/tsconfig.json

@@ -2,7 +2,8 @@
   "extends": "../../config/tsconfig.base.json",
   "compilerOptions": {
     "outDir": "dist",
-    "strict": true
+    "strict": true,
+    "preserveConstEnums": true
   },
   "exclude": ["dist/**/*"]
 }