fix(core): allow abstract class as injection token

closes angular#23611

Author: trotyl

packages/compiler-cli/integrationtest/bazel/injectable_def/app/src/dep.ts

@@ -38,4 +38,4 @@ export class DepAppModule {
 @Injectable({providedIn: DepAppModule})
 export class ShakeableService {
   constructor(readonly normal: NormalService) {}
-}
+}

packages/compiler-cli/integrationtest/bazel/injectable_def/app/src/token.ts

@@ -18,7 +18,7 @@ export class TokenModule {
 
 export const TOKEN = new InjectionToken('test', {
   providedIn: TokenModule,
-  factory: () => new Service(inject(Dep)),
+  factory: () => new Service(inject(Dep), inject(AbstractDep)),
 });
 
 
@@ -49,6 +49,11 @@ export class Dep {
   readonly data = 'fromToken';
 }
 
+@Injectable({providedIn: 'root', useValue: {value: 42}})
+export abstract class AbstractDep {
+  abstract value: number;
+}
+
 export class Service {
-  constructor(readonly dep: Dep) {}
+  constructor(readonly dep: Dep, unused: AbstractDep) {}
 }

packages/compiler/src/core.ts

@@ -154,7 +154,8 @@ export const createSelf = makeMetadataFactory('Self');
 export const createSkipSelf = makeMetadataFactory('SkipSelf');
 export const createHost = makeMetadataFactory('Host');
 
-export interface Type extends Function { new (...args: any[]): any; }
+export interface Type extends Function { prototype: any; }
+
 export const Type = Function;
 
 export enum SecurityContext {

packages/core/src/application_ref.ts

@@ -465,7 +465,7 @@ export class ApplicationRef {
 
     // Create a factory associated with the current module if it's not bound to some other
     const ngModule = componentFactory instanceof ComponentFactoryBoundToModule ?
-        null :
+        undefined :
         this._injector.get(NgModuleRef);
     const selectorOrNode = rootSelectorOrNode || componentFactory.selector;
     const compRef = componentFactory.create(Injector.NULL, [], selectorOrNode, ngModule);

packages/core/src/di/r3_injector.ts

@@ -7,7 +7,7 @@
  */
 
 import {OnDestroy} from '../metadata/lifecycle_hooks';
-import {Type} from '../type';
+import {Constructor, Type} from '../type';
 import {stringify} from '../util';
 
 import {InjectableDef, InjectableType, InjectorType, InjectorTypeWithProviders, getInjectableDef, getInjectorDef} from './defs';
@@ -336,7 +336,7 @@ function injectableDefRecord(token: Type<any>| InjectionToken<any>): Record<any>
     }
     // TODO(alxhub): there should probably be a strict mode which throws here instead of assuming a
     // no-args constructor.
-    return makeRecord(() => new (token as Type<any>)());
+    return makeRecord(() => new (token as Constructor<any>)());
   }
   return makeRecord(injectableDef.factory);
 }
@@ -358,7 +358,7 @@ function providerToRecord(provider: SingleProvider): Record<any> {
     } else {
       const classRef = (provider as StaticClassProvider | ClassProvider).useClass || token;
       if (hasDeps(provider)) {
-        factory = () => new (classRef)(...injectArgs(provider.deps));
+        factory = () => new (classRef as Constructor<any>)(...injectArgs(provider.deps));
       } else {
         return injectableDefRecord(classRef);
       }

packages/core/src/reflection/reflection_capabilities.ts

@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {Type, isType} from '../type';
+import {Constructor, Type, isType} from '../type';
 import {global, stringify} from '../util';
 import {ANNOTATIONS, PARAMETERS, PROP_METADATA} from '../util/decorators';
 
@@ -29,7 +29,7 @@ export class ReflectionCapabilities implements PlatformReflectionCapabilities {
 
   isReflectionEnabled(): boolean { return true; }
 
-  factory<T>(t: Type<T>): (args: any[]) => T { return (...args: any[]) => new t(...args); }
+  factory<T>(t: Constructor<T>): (args: any[]) => T { return (...args: any[]) => new t(...args); }
 
   /** @internal */
   _zipTypesAndAnnotations(paramTypes: any[], paramAnnotations: any[]): any[][] {

packages/core/src/render3/definition.ts

@@ -296,13 +296,13 @@ export function defineComponent<T>(componentDefinition: {
     declaredInputs: declaredInputs,
     outputs: invertObject(componentDefinition.outputs),
     exportAs: componentDefinition.exportAs || null,
-    onInit: type.prototype.ngOnInit || null,
-    doCheck: type.prototype.ngDoCheck || null,
-    afterContentInit: type.prototype.ngAfterContentInit || null,
-    afterContentChecked: type.prototype.ngAfterContentChecked || null,
-    afterViewInit: type.prototype.ngAfterViewInit || null,
-    afterViewChecked: type.prototype.ngAfterViewChecked || null,
-    onDestroy: type.prototype.ngOnDestroy || null,
+    onInit: (type.prototype as any).ngOnInit || null,
+    doCheck: (type.prototype as any).ngDoCheck || null,
+    afterContentInit: (type.prototype as any).ngAfterContentInit || null,
+    afterContentChecked: (type.prototype as any).ngAfterContentChecked || null,
+    afterViewInit: (type.prototype as any).ngAfterViewInit || null,
+    afterViewChecked: (type.prototype as any).ngAfterViewChecked || null,
+    onDestroy: (type.prototype as any).ngOnDestroy || null,
     onPush: componentDefinition.changeDetection === ChangeDetectionStrategy.OnPush,
     directiveDefs: directiveTypes ?
         () => (typeof directiveTypes === 'function' ? directiveTypes() : directiveTypes)
@@ -660,7 +660,7 @@ export function definePipe<T>(pipeDef: {
     name: pipeDef.name,
     factory: pipeDef.factory,
     pure: pipeDef.pure !== false,
-    onDestroy: pipeDef.type.prototype.ngOnDestroy || null
+    onDestroy: (pipeDef.type.prototype as any).ngOnDestroy || null
   }) as never;
 }
 

packages/core/src/type.ts

@@ -22,4 +22,6 @@ export function isType(v: any): v is Type<any> {
   return typeof v === 'function';
 }
 
-export interface Type<T> extends Function { new (...args: any[]): T; }
+export interface Type<T> extends Function { prototype: T; }
+
+export interface Constructor<T> extends Type<T> { new (...args: any[]): T; }

packages/core/test/render3/compiler_canonical/small_app_spec.ts

@@ -101,7 +101,8 @@ class ToDoAppComponent {
 
 // NON-NORMATIVE
 (ToDoAppComponent.ngComponentDef as r3.ComponentDefInternal<any>).directiveDefs = () =>
-    [ToDoItemComponent.ngComponentDef, (NgForOf as r3.DirectiveType<NgForOf<any>>).ngDirectiveDef];
+    [ToDoItemComponent.ngComponentDef,
+     (NgForOf as any as r3.DirectiveType<NgForOf<any>>).ngDirectiveDef];
 // /NON-NORMATIVE
 
 @Component({