improve: tests

src/app/footer/footer.component.spec.ts

@@ -1,23 +1,105 @@
 import type { ComponentFixture } from '@angular/core/testing';
 import { TestBed } from '@angular/core/testing';
+import { provideRouter } from '@angular/router';
 
 import { FooterComponent } from './footer.component';
+import { global } from '../../global';
 
 describe('FooterComponent', (): void => {
-  let component: FooterComponent;
   let fixture: ComponentFixture<FooterComponent>;
+  let component: FooterComponent;
+
+  interface ComponentAccess {
+    currentYear: number;
+    global: typeof global;
+  }
+
+  let comp: ComponentAccess;
 
   beforeEach(async (): Promise<void> => {
     await TestBed.configureTestingModule({
       imports: [FooterComponent],
+      providers: [provideRouter([])],
     }).compileComponents();
 
     fixture = TestBed.createComponent(FooterComponent);
     component = fixture.componentInstance;
+    comp = component as unknown as ComponentAccess;
     fixture.detectChanges();
   });
 
   it('should create', (): void => {
     expect(component).toBeTruthy();
   });
+
+  describe('currentYear', (): void => {
+    it('should equal the current calendar year', (): void => {
+      expect(comp.currentYear).toBe(new Date().getFullYear());
+    });
+
+    it('should be a four-digit number', (): void => {
+      expect(comp.currentYear).toBeGreaterThanOrEqual(2024);
+      expect(comp.currentYear).toBeLessThan(2100);
+    });
+  });
+
+  describe('global data', (): void => {
+    it('should reference the shared global object', (): void => {
+      expect(comp.global).toBe(global);
+    });
+
+    it('should expose a non-empty firstname', (): void => {
+      expect(comp.global.firstname.length).toBeGreaterThan(0);
+    });
+
+    it('should expose a non-empty lastname', (): void => {
+      expect(comp.global.lastname.length).toBeGreaterThan(0);
+    });
+  });
+
+  describe('Template', (): void => {
+    it('should render the current year in the copyright line', (): void => {
+      const el = fixture.nativeElement as HTMLElement;
+      expect(el.textContent).toContain(String(new Date().getFullYear()));
+    });
+
+    it('should render the author firstname', (): void => {
+      const el = fixture.nativeElement as HTMLElement;
+      expect(el.textContent).toContain(global.firstname);
+    });
+
+    it('should render the author lastname', (): void => {
+      const el = fixture.nativeElement as HTMLElement;
+      expect(el.textContent).toContain(global.lastname);
+    });
+
+    it('should render an imprint link with text "Imprint"', (): void => {
+      const el = fixture.nativeElement as HTMLElement;
+      const links = Array.from(el.querySelectorAll('a'));
+      const imprintLink = links.find((a): boolean => a.textContent?.trim() === 'Imprint');
+      expect(imprintLink).toBeTruthy();
+    });
+
+    it('should contain a footer element', (): void => {
+      const el = fixture.nativeElement as HTMLElement;
+      expect(el.querySelector('footer')).not.toBeNull();
+    });
+  });
+
+  describe('Performance', (): void => {
+    it('should create and detect changes within 50 ms', (): void => {
+      const start = performance.now();
+      const f = TestBed.createComponent(FooterComponent);
+      f.detectChanges();
+      expect(performance.now() - start).toBeLessThan(50);
+    });
+
+    it('should run 20 consecutive change detection cycles within 100 ms', (): void => {
+      const start = performance.now();
+      for (let i = 0; i < 20; i++) {
+        fixture.detectChanges();
+      }
+      expect(performance.now() - start).toBeLessThan(100);
+    });
+  });
 });