add unit tests

src/app/modules/songs/song/edit/edit-song.guard.spec.ts

@@ -1,5 +1,4 @@
 import {TestBed} from '@angular/core/testing';
-
 import {EditSongGuard} from './edit-song.guard';
 
 describe('EditSongGuard', () => {
@@ -11,6 +10,22 @@ describe('EditSongGuard', () => {
   });
 
   it('should be created', () => {
-    void expect(guard).toBeTruthy();
+    expect(guard).toBeTruthy();
+  });
+
+  it('should allow navigation when there is no nested editSongComponent', () => {
+    const result = guard.canDeactivate({editSongComponent: null} as never, {} as never, {} as never, {} as never);
+
+    expect(result).toBeTrue();
+  });
+
+  it('should delegate to askForSave on the nested editSongComponent', async () => {
+    const nextState = {url: '/songs'} as never;
+    const askForSave = jasmine.createSpy('askForSave').and.resolveTo(true);
+
+    const result = await guard.canDeactivate({editSongComponent: {askForSave}} as never, {} as never, {} as never, nextState);
+
+    expect(askForSave).toHaveBeenCalledWith(nextState);
+    expect(result).toBeTrue();
   });
 });