docs: update examples for tree-shakeable providers (#22961)

PR Close #22961

aio/content/examples/dependency-injection/e2e/app.e2e-spec.ts

@@ -178,6 +178,11 @@ describe('Dependency Injection Tests', function () {
         expect(heroes.count()).toBeGreaterThan(0);
       });
 
+      it('authorized user should have multiple authorized heroes with tree-shakeable HeroesService', function () {
+        let heroes = element.all(by.css('#tspAuthorized app-hero-list div'));
+        expect(heroes.count()).toBeGreaterThan(0);
+      });
+
       it('authorized user should have secret heroes', function () {
         let heroes = element.all(by.css('#authorized app-hero-list div'));
         expect(heroes.count()).toBeGreaterThan(0);

aio/content/examples/dependency-injection/src/app/app.component.ts

@@ -21,6 +21,7 @@ import { UserService } from './user.service';
     <p>
     <app-heroes id="authorized" *ngIf="isAuthorized"></app-heroes>
     <app-heroes id="unauthorized" *ngIf="!isAuthorized"></app-heroes>
+    <app-heroes-tsp id="tspAuthorized" *ngIf="isAuthorized"></app-heroes-tsp>
     <app-providers></app-providers>
   `
 })

aio/content/examples/dependency-injection/src/app/app.module.ts

@@ -6,6 +6,7 @@ import { APP_CONFIG, HERO_DI_CONFIG }    from './app.config';
 import { AppComponent } from './app.component';
 import { CarComponent } from './car/car.component';
 import { HeroesComponent } from './heroes/heroes.component';
+import { HeroesTspComponent } from './heroes/heroes-tsp.component';
 import { HeroListComponent } from './heroes/hero-list.component';
 import { InjectorComponent } from './injector.component';
 import { Logger } from './logger.service';
@@ -25,6 +26,7 @@ import { ProvidersModule } from './providers.module';
     CarComponent,
     HeroesComponent,
     // #enddocregion ngmodule
+    HeroesTspComponent,
     HeroListComponent,
     InjectorComponent,
     TestComponent

aio/content/examples/dependency-injection/src/app/heroes/hero.module.ts

@@ -0,0 +1,6 @@
+// #docregion
+import { NgModule } from '@angular/core';
+
+@NgModule({})
+export class HeroModule {
+}

aio/content/examples/dependency-injection/src/app/heroes/hero.service.0.ts

@@ -1,6 +1,8 @@
 import { Injectable } from '@angular/core';
 
-@Injectable()
+@Injectable({
+  providedIn: 'root',
+})
 export class HeroService {
   constructor() { }
 }

aio/content/examples/dependency-injection/src/app/heroes/hero.service.1.ts

@@ -2,7 +2,9 @@
 import { Injectable } from '@angular/core';
 import { HEROES }     from './mock-heroes';
 
-@Injectable()
+@Injectable({
+  providedIn: 'root',
+})
 export class HeroService {
   getHeroes() { return HEROES; }
 }

aio/content/examples/dependency-injection/src/app/heroes/hero.service.2.ts

@@ -3,7 +3,9 @@ import { Injectable } from '@angular/core';
 import { HEROES }     from './mock-heroes';
 import { Logger }     from '../logger.service';
 
-@Injectable()
+@Injectable({
+  providedIn: 'root',
+})
 export class HeroService {
 
   // #docregion ctor

aio/content/examples/dependency-injection/src/app/heroes/hero.service.3.ts

@@ -0,0 +1,13 @@
+// #docregion
+import { Injectable } from '@angular/core';
+import { HEROES }     from './mock-heroes';
+
+@Injectable({
+  // we declare that this service should be created
+  // by the root application injector.
+
+  providedIn: 'root',
+})
+export class HeroService {
+  getHeroes() { return HEROES; }
+}

aio/content/examples/dependency-injection/src/app/heroes/hero.service.4.ts

@@ -0,0 +1,14 @@
+// #docregion
+import { Injectable } from '@angular/core';
+import { HeroModule } from './hero.module';
+import { HEROES }     from './mock-heroes';
+
+@Injectable({
+  // we declare that this service should be created
+  // by any injector that includes HeroModule.
+
+  providedIn: HeroModule,
+})
+export class HeroService {
+  getHeroes() { return HEROES; }
+}

aio/content/examples/dependency-injection/src/app/heroes/hero.service.ts

@@ -2,8 +2,14 @@
 import { Injectable } from '@angular/core';
 import { HEROES }     from './mock-heroes';
 import { Logger }     from '../logger.service';
+import { UserService } from '../user.service';
 
-@Injectable()
+@Injectable({
+  providedIn: 'root',
+  useFactory: (logger: Logger, userService: UserService) =>
+      new HeroService(logger, userService.user.isAuthorized),
+  deps: [Logger, UserService],
+})
 export class HeroService {
   // #docregion internals
   constructor(

aio/content/examples/dependency-injection/src/app/heroes/heroes-tsp.component.ts

@@ -0,0 +1,16 @@
+import { Component } from '@angular/core';
+
+/**
+ * A version of `HeroesComponent` that does not provide the `HeroService` (and thus relies on its
+ * `Injectable`-declared provider) in order to function.
+ *
+ * TSP stands for Tree-Shakeable Provider.
+ */
+@Component({
+  selector: 'app-heroes-tsp',
+  template: `
+    <h2>Heroes</h2>
+    <app-hero-list></app-hero-list>
+  `
+})
+export class HeroesTspComponent { }

aio/content/examples/dependency-injection/src/app/tree-shaking/app.module.ts

@@ -0,0 +1,15 @@
+import { NgModule }      from '@angular/core';
+import { BrowserModule } from '@angular/platform-browser';
+import { RouterModule }  from '@angular/router';
+import { ServiceModule } from './service-and-module';
+
+// #docregion
+@NgModule({
+  imports: [
+    BrowserModule,
+    RouterModule.forRoot([]),
+    ServiceModule,
+  ],
+})
+export class AppModule {
+}

aio/content/examples/dependency-injection/src/app/tree-shaking/service-and-module.ts

@@ -0,0 +1,14 @@
+// #docregion
+import { Injectable, NgModule } from '@angular/core';
+
+@Injectable()
+export class Service {
+  doSomething(): void {
+  }
+}
+
+@NgModule({
+  providers: [Service],
+})
+export class ServiceModule {
+}

aio/content/examples/dependency-injection/src/app/tree-shaking/service.0.ts

@@ -0,0 +1,11 @@
+import { Injectable } from '@angular/core';
+
+// #docregion
+@Injectable({
+  providedIn: 'root',
+  useFactory: () => new Service('dependency'),
+})
+export class Service {
+  constructor(private dep: string) {
+  }
+}

aio/content/examples/dependency-injection/src/app/tree-shaking/service.ts

@@ -0,0 +1,8 @@
+import { Injectable } from '@angular/core';
+
+// #docregion
+@Injectable({
+  providedIn: 'root',
+})
+export class Service {
+}

aio/content/examples/dependency-injection/stackblitz.json

@@ -3,7 +3,7 @@
   "files":[
     "!**/*.d.ts",
     "!**/*.js",
-    "!**/*.[0,1,2].*",
+    "!**/*.[0,1,2,3,4].*",
     "!**/dummy.module.ts"
   ],
   "tags": ["dependency", "di"]

aio/content/examples/providers/src/app/app.module.ts

@@ -6,7 +6,6 @@ import { UserService } from './user.service';
 
 @NgModule({
   imports:      [ BrowserModule ],
-  providers:    [ UserService ],
   declarations: [ AppComponent ],
   bootstrap:    [ AppComponent ]
 })

aio/content/examples/providers/src/app/user.module.ts

@@ -0,0 +1,9 @@
+import { NgModule } from '@angular/core';
+
+import { UserService } from './user.service';
+
+@NgModule({
+  providers: [UserService],
+})
+export class UserModule {
+}

aio/content/examples/providers/src/app/user.service.0.ts

@@ -0,0 +1,7 @@
+import { Injectable } from '@angular/core';
+
+@Injectable({
+  providedIn: 'root',
+})
+export class UserService {
+}

aio/content/examples/providers/src/app/user.service.1.ts

@@ -0,0 +1,8 @@
+import { Injectable } from '@angular/core';
+import { UserModule } from './user.module';
+
+@Injectable({
+  providedIn: UserModule,
+})
+export class UserService {
+}

aio/content/examples/providers/src/app/user.service.spec.ts

@@ -3,9 +3,7 @@ import { UserService } from './user.service';
 
 describe('UserService', () => {
   beforeEach(() => {
-    TestBed.configureTestingModule({
-      providers: [UserService]
-    });
+    TestBed.configureTestingModule({});
   });
 
   it('should ...', inject([UserService], (service: UserService) => {

aio/content/examples/providers/src/app/user.service.ts

@@ -5,7 +5,9 @@ export class User {
   name: string;
 }
 
-@Injectable()
+@Injectable({
+  providedIn: 'root',
+})
 export class UserService {
 
   constructor() { }

aio/content/examples/providers/stackblitz.json

@@ -3,7 +3,7 @@
   "files": [
     "!**/*.d.ts",
     "!**/*.js",
-    "!**/*.[1,2].*"
+    "!**/*.[0,1,2].*"
   ],
   "file": "src/app/app.component.ts",
   "tags": ["providers"]

aio/content/examples/styleguide/src/07-03/app/app.component.ts

@@ -8,6 +8,5 @@ import { HeroService } from './heroes';
   template: `
       <toh-heroes></toh-heroes>
     `,
-  providers: [HeroService]
 })
 export class AppComponent {}

aio/content/examples/styleguide/src/07-03/app/heroes/shared/hero.service.ts

@@ -5,7 +5,9 @@ import { Observable, of } from 'rxjs';
 
 import { Hero } from './hero.model';
 
-@Injectable()
+@Injectable({
+  providedIn: 'root',
+})
 export class HeroService {
   getHeroes() {
     let heroes: Hero[] = [];