refactor(core): Update error for both zone and zoneless to be only for apps (#55813)

Developers may want to enable zoneless for all tests by default by
adding the zoneless provider to `initTestEnvironment` and then
temporarily disabling it for individual tests with the zone provider
until they can be made zoneless compatible.

PR Close #55813

packages/core/src/application/create_application.ts

@@ -8,7 +8,10 @@
 
 import {Subscription} from 'rxjs';
 
-import {internalProvideZoneChangeDetection} from '../change_detection/scheduling/ng_zone_scheduling';
+import {
+  internalProvideZoneChangeDetection,
+  PROVIDED_NG_ZONE,
+} from '../change_detection/scheduling/ng_zone_scheduling';
 import {EnvironmentProviders, Provider, StaticProvider} from '../di/interface/provider';
 import {EnvironmentInjector} from '../di/r3_injector';
 import {ErrorHandler} from '../error_handler';
@@ -26,6 +29,7 @@ import {NgZone} from '../zone/ng_zone';
 
 import {ApplicationInitStatus} from './application_init';
 import {_callAndReportToErrorHandler, ApplicationRef} from './application_ref';
+import {PROVIDED_ZONELESS} from '../change_detection/scheduling/zoneless_scheduling';
 
 /**
  * Internal create application API that implements the core application creation logic and optional
@@ -70,11 +74,20 @@ export function internalCreateApplication(config: {
     return ngZone.run(() => {
       envInjector.resolveInjectorInitializers();
       const exceptionHandler: ErrorHandler | null = envInjector.get(ErrorHandler, null);
-      if ((typeof ngDevMode === 'undefined' || ngDevMode) && !exceptionHandler) {
-        throw new RuntimeError(
-          RuntimeErrorCode.MISSING_REQUIRED_INJECTABLE_IN_BOOTSTRAP,
-          'No `ErrorHandler` found in the Dependency Injection tree.',
-        );
+      if (typeof ngDevMode === 'undefined' || ngDevMode) {
+        if (!exceptionHandler) {
+          throw new RuntimeError(
+            RuntimeErrorCode.MISSING_REQUIRED_INJECTABLE_IN_BOOTSTRAP,
+            'No `ErrorHandler` found in the Dependency Injection tree.',
+          );
+        }
+        if (envInjector.get(PROVIDED_ZONELESS) && envInjector.get(PROVIDED_NG_ZONE)) {
+          throw new RuntimeError(
+            RuntimeErrorCode.PROVIDED_BOTH_ZONE_AND_ZONELESS,
+            'Invalid change detection configuration: ' +
+              'provideZoneChangeDetection and provideExperimentalZonelessChangeDetection cannot be used together.',
+          );
+        }
       }
 
       let onErrorSubscription: Subscription;

packages/core/src/change_detection/scheduling/ng_zone_scheduling.ts

@@ -38,7 +38,6 @@ export class NgZoneChangeDetectionScheduler {
   private readonly zone = inject(NgZone);
   private readonly changeDetectionScheduler = inject(ChangeDetectionScheduler, {optional: true});
   private readonly applicationRef = inject(ApplicationRef);
-  private readonly zonelessEnabled = inject(ZONELESS_ENABLED);
 
   private _onMicrotaskEmptySubscription?: Subscription;
 
@@ -73,6 +72,7 @@ export class NgZoneChangeDetectionScheduler {
  */
 export const PROVIDED_NG_ZONE = new InjectionToken<boolean>(
   typeof ngDevMode === 'undefined' || ngDevMode ? 'provideZoneChangeDetection token' : '',
+  {factory: () => false},
 );
 
 export function internalProvideZoneChangeDetection({
@@ -167,8 +167,9 @@ export function provideZoneChangeDetection(options?: NgZoneOptions): Environment
   });
   return makeEnvironmentProviders([
     typeof ngDevMode === 'undefined' || ngDevMode
-      ? [{provide: PROVIDED_NG_ZONE, useValue: true}, bothZoneAndZonelessErrorCheckProvider]
+      ? [{provide: PROVIDED_NG_ZONE, useValue: true}]
       : [],
+    {provide: ZONELESS_ENABLED, useValue: false},
     zoneProviders,
   ]);
 }
@@ -301,19 +302,3 @@ export class ZoneStablePendingTask {
     this.subscription.unsubscribe();
   }
 }
-
-const bothZoneAndZonelessErrorCheckProvider = {
-  provide: ENVIRONMENT_INITIALIZER,
-  multi: true,
-  useFactory: () => {
-    const providedZoneless = inject(ZONELESS_ENABLED, {optional: true});
-    if (providedZoneless) {
-      throw new RuntimeError(
-        RuntimeErrorCode.PROVIDED_BOTH_ZONE_AND_ZONELESS,
-        'Invalid change detection configuration: ' +
-          'provideZoneChangeDetection and provideExperimentalZonelessChangeDetection cannot be used together.',
-      );
-    }
-    return () => {};
-  },
-};

packages/core/src/change_detection/scheduling/zoneless_scheduling.ts

@@ -59,6 +59,12 @@ export const ZONELESS_ENABLED = new InjectionToken<boolean>(
   {providedIn: 'root', factory: () => false},
 );
 
+/** Token used to indicate `provideExperimentalZonelessChangeDetection` was used. */
+export const PROVIDED_ZONELESS = new InjectionToken<boolean>(
+  typeof ngDevMode === 'undefined' || ngDevMode ? 'Zoneless provided' : '',
+  {providedIn: 'root', factory: () => false},
+);
+
 export const ZONELESS_SCHEDULER_DISABLED = new InjectionToken<boolean>(
   typeof ngDevMode === 'undefined' || ngDevMode ? 'scheduler disabled' : '',
 );

packages/core/src/change_detection/scheduling/zoneless_scheduling_impl.ts

@@ -26,6 +26,7 @@ import {
   ChangeDetectionScheduler,
   NotificationSource,
   ZONELESS_ENABLED,
+  PROVIDED_ZONELESS,
   ZONELESS_SCHEDULER_DISABLED,
 } from './zoneless_scheduling';
 
@@ -297,5 +298,8 @@ export function provideExperimentalZonelessChangeDetection(): EnvironmentProvide
     {provide: ChangeDetectionScheduler, useExisting: ChangeDetectionSchedulerImpl},
     {provide: NgZone, useClass: NoopNgZone},
     {provide: ZONELESS_ENABLED, useValue: true},
+    typeof ngDevMode === 'undefined' || ngDevMode
+      ? [{provide: PROVIDED_ZONELESS, useValue: true}]
+      : [],
   ]);
 }

packages/core/src/platform/platform_ref.ts

@@ -95,25 +95,20 @@ export class PlatformRef {
         internalProvideZoneChangeDetection({ngZoneFactory: () => ngZone, ignoreChangesOutsideZone}),
       );
 
-      if (
-        (typeof ngDevMode === 'undefined' || ngDevMode) &&
-        moduleRef.injector.get(PROVIDED_NG_ZONE, null) !== null
-      ) {
-        throw new RuntimeError(
-          RuntimeErrorCode.PROVIDER_IN_WRONG_CONTEXT,
-          '`bootstrapModule` does not support `provideZoneChangeDetection`. Use `BootstrapOptions` instead.',
-        );
-      }
-      if (
-        (typeof ngDevMode === 'undefined' || ngDevMode) &&
-        moduleRef.injector.get(ZONELESS_ENABLED, null) &&
-        options?.ngZone !== 'noop'
-      ) {
-        throw new RuntimeError(
-          RuntimeErrorCode.PROVIDED_BOTH_ZONE_AND_ZONELESS,
-          'Invalid change detection configuration: ' +
-            "`ngZone: 'noop'` must be set in `BootstrapOptions` with provideExperimentalZonelessChangeDetection.",
-        );
+      if (typeof ngDevMode === 'undefined' || ngDevMode) {
+        if (moduleRef.injector.get(PROVIDED_NG_ZONE)) {
+          throw new RuntimeError(
+            RuntimeErrorCode.PROVIDER_IN_WRONG_CONTEXT,
+            '`bootstrapModule` does not support `provideZoneChangeDetection`. Use `BootstrapOptions` instead.',
+          );
+        }
+        if (moduleRef.injector.get(ZONELESS_ENABLED) && options?.ngZone !== 'noop') {
+          throw new RuntimeError(
+            RuntimeErrorCode.PROVIDED_BOTH_ZONE_AND_ZONELESS,
+            'Invalid change detection configuration: ' +
+              "`ngZone: 'noop'` must be set in `BootstrapOptions` with provideExperimentalZonelessChangeDetection.",
+          );
+        }
       }
 
       const exceptionHandler = moduleRef.injector.get(ErrorHandler, null);

packages/core/test/acceptance/change_detection_spec.ts

@@ -45,6 +45,14 @@ import {expect} from '@angular/platform-browser/testing/src/matchers';
 import {BehaviorSubject} from 'rxjs';
 
 describe('change detection', () => {
+  it('can provide zone and zoneless (last one wins like any other provider) in TestBed', () => {
+    expect(() => {
+      TestBed.configureTestingModule({
+        providers: [provideExperimentalZonelessChangeDetection(), provideZoneChangeDetection()],
+      });
+      TestBed.inject(ApplicationRef);
+    }).not.toThrow();
+  });
   describe('embedded views', () => {
     @Directive({selector: '[viewManipulation]', exportAs: 'vm'})
     class ViewManipulation {

packages/core/test/change_detection_scheduler_spec.ts

@@ -64,14 +64,6 @@ describe('Angular with zoneless enabled', () => {
     });
   });
 
-  it('throws an error if used with zone provider', () => {
-    TestBed.configureTestingModule({providers: [provideZoneChangeDetection()]});
-
-    expect(() => TestBed.inject(NgZone)).toThrowError(
-      /NG0408: Invalid change detection configuration/,
-    );
-  });
-
   describe('notifies scheduler', () => {
     it('contributes to application stableness', async () => {
       const val = signal('initial');