SpyNgModuleFactoryLoader

What it does

Allows to simulate the loading of ng modules in tests.

How to use

const loader = TestBed.get(NgModuleFactoryLoader);

@Component({template: 'lazy-loaded'})
class LazyLoadedComponent {}
@NgModule({
  declarations: [LazyLoadedComponent],
  imports: [RouterModule.forChild([{path: 'loaded', component: LazyLoadedComponent}])]
})

class LoadedModule {}

// sets up stubbedModules
loader.stubbedModules = {lazyModule: LoadedModule};

router.resetConfig([
  {path: 'lazy', loadChildren: 'lazyModule'},
]);

router.navigateByUrl('/lazy/loaded');