test: added home component test

Author: karanba

src/app/courses/home/home.component.spec.ts

@@ -1,3 +1,4 @@
+import { filter } from 'rxjs/operators';
 import { async, ComponentFixture, fakeAsync, flush, flushMicrotasks, TestBed, waitForAsync } from '@angular/core/testing';
 import { CoursesModule } from '../courses.module';
 import { DebugElement } from '@angular/core';
@@ -21,6 +22,10 @@ describe('HomeComponent', () => {
   let fixture: ComponentFixture<HomeComponent>;
   let component: HomeComponent;
   let el: DebugElement;
+  let coursesService: any;
+
+  const beginnerCourses = setupCourses()
+    .filter(course => course.category == 'BEGINNER');
 
   beforeEach(waitForAsync(() => {
     const coursesServiceSpy = jasmine.createSpyObj('CoursesService', ['findAllCourses']);
@@ -42,6 +47,7 @@ describe('HomeComponent', () => {
         fixture = TestBed.createComponent(HomeComponent);
         component = fixture.componentInstance;
         el = fixture.debugElement;
+        coursesService = TestBed.inject(CoursesService);
       });
 
   }));
@@ -54,9 +60,11 @@ describe('HomeComponent', () => {
 
 
   it("should display only beginner courses", () => {
-
-    pending();
-
+    coursesService.findAllCourses.and
+      .returnValue(of(beginnerCourses));
+    fixture.detectChanges();
+    const tabs = el.queryAll(By.css(".mat-tab-label"));
+    expect(tabs.length).toBe(1, "unexpected number of tabs found");
   });