From 3261d1439198869a66ffdd05298af56622da0449 Mon Sep 17 00:00:00 2001
From: Andrew Scott <atscott@google.com>
Date: Mon, 21 Apr 2025 09:46:11 -0700
Subject: [PATCH] refactor(core): `NgZone.onError` reports to application error
 handler (#60946)

This commit ensures that errors from the `NgZone.onError` subscription
in bootstrap are reported to the internal application error handler.
Practically speaking, this should not affect anything today, as the
application handler goes directly to the `ErrorHandler` from the root.
While TestBed installs an application error handler that rethrows,
`TestBed.createComponent` does not create components through this
bootstrap function.

PR Close #60946
---
 packages/core/src/platform/bootstrap.ts | 25 +++++++------------------
 1 file changed, 7 insertions(+), 18 deletions(-)

diff --git a/packages/core/src/platform/bootstrap.ts b/packages/core/src/platform/bootstrap.ts
index a20ede52fb3..3ddcabdf10e 100644
--- a/packages/core/src/platform/bootstrap.ts
+++ b/packages/core/src/platform/bootstrap.ts
@@ -9,7 +9,7 @@ import {Subscription} from 'rxjs';
 
 import {PROVIDED_NG_ZONE} from '../change_detection/scheduling/ng_zone_scheduling';
 import {R3Injector} from '../di/r3_injector';
-import {ErrorHandler} from '../error_handler';
+import {INTERNAL_APPLICATION_ERROR_HANDLER} from '../error_handler';
 import {RuntimeError, RuntimeErrorCode} from '../errors';
 import {DEFAULT_LOCALE_ID} from '../i18n/localization';
 import {LOCALE_ID} from '../i18n/tokens';
@@ -90,17 +90,8 @@ export function bootstrap<M>(
     } else {
       config.moduleRef.resolveInjectorInitializers();
     }
-    const exceptionHandler = envInjector.get(ErrorHandler, null);
+    const exceptionHandler = envInjector.get(INTERNAL_APPLICATION_ERROR_HANDLER);
     if (typeof ngDevMode === 'undefined' || ngDevMode) {
-      if (exceptionHandler === null) {
-        const errorMessage = isApplicationBootstrapConfig(config)
-          ? 'No `ErrorHandler` found in the Dependency Injection tree.'
-          : 'No ErrorHandler. Is platform module (BrowserModule) included';
-        throw new RuntimeError(
-          RuntimeErrorCode.MISSING_REQUIRED_INJECTABLE_IN_BOOTSTRAP,
-          errorMessage,
-        );
-      }
       if (envInjector.get(PROVIDED_ZONELESS) && envInjector.get(PROVIDED_NG_ZONE)) {
         throw new RuntimeError(
           RuntimeErrorCode.PROVIDED_BOTH_ZONE_AND_ZONELESS,
@@ -113,9 +104,7 @@ export function bootstrap<M>(
     let onErrorSubscription: Subscription;
     ngZone.runOutsideAngular(() => {
       onErrorSubscription = ngZone.onError.subscribe({
-        next: (error: any) => {
-          exceptionHandler!.handleError(error);
-        },
+        next: exceptionHandler,
       });
     });
 
@@ -142,7 +131,7 @@ export function bootstrap<M>(
       });
     }
 
-    return _callAndReportToErrorHandler(exceptionHandler!, ngZone, () => {
+    return _callAndReportToErrorHandler(exceptionHandler, ngZone, () => {
       const initStatus = envInjector.get(ApplicationInitStatus);
       initStatus.runInitializers();
 
@@ -203,7 +192,7 @@ function moduleDoBootstrap(
 }
 
 function _callAndReportToErrorHandler(
-  errorHandler: ErrorHandler,
+  errorHandler: (e: unknown) => void,
   ngZone: NgZone,
   callback: () => any,
 ): any {
@@ -211,7 +200,7 @@ function _callAndReportToErrorHandler(
     const result = callback();
     if (isPromise(result)) {
       return result.catch((e: any) => {
-        ngZone.runOutsideAngular(() => errorHandler.handleError(e));
+        ngZone.runOutsideAngular(() => errorHandler(e));
         // rethrow as the exception handler might not do it
         throw e;
       });
@@ -219,7 +208,7 @@ function _callAndReportToErrorHandler(
 
     return result;
   } catch (e) {
-    ngZone.runOutsideAngular(() => errorHandler.handleError(e));
+    ngZone.runOutsideAngular(() => errorHandler(e));
     // rethrow as the exception handler might not do it
     throw e;
   }