Add service comment

src/app/app.component.html

@@ -11,3 +11,6 @@
     <router-outlet></router-outlet>
   </div>
 </div>
+
+
+

src/app/comment.service.spec.ts

+import { TestBed, inject } from '@angular/core/testing';
+
+import { CommentService } from './comment.service';
+
+describe('CommentService', () => {
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      providers: [CommentService]
+    });
+  });
+
+  it('should be created', inject([CommentService], (service: CommentService) => {
+    expect(service).toBeTruthy();
+  }));
+});

src/app/comment.service.ts

+import { Injectable } from '@angular/core';
+
+@Injectable()
+export class CommentService {
+
+  constructor() { }
+
+}