Unit Testing a class that uses Injector

[Brian Wilkinson]

I have a class that uses the Injector as below

export class DetailsComponent implements OnInit, IContainer {

    views: ViewDetails[];

    // static true run before change detection

    @ViewChild('detailsRegion', { read: ViewContainerRef, static: true })

    detailsRegion: ViewContainerRef;

    constructor(private injector: Injector) {}

    private insertView(

        viewContainer: ViewContainerRef,

        componentFactory: ComponentFactory<any>

    ) {

        const compRef = componentFactory.create(this.injector);

        viewContainer.clear();

        viewContainer.insert(compRef.hostView);

    }

    ngOnInit() {}

    public insertsView(views: ViewDetails[]): void {

        this.views = views;

        views.forEach(v => {

            switch (v.region) {

                case ContainerView.Details:

                    this.insertView(this.detailsRegion, v.componentFactory);

                    break;

                case ContainerView.Master:

                case ContainerView.Map:

                    throw new Error('Out of Range');

            }

        });

    }

}

When writing the unit test how do I capture the Injector so I can set up the component factory spy object to ensure that create is correctly called with it. I have tried setting up a provider in TestBed.configureTestingModule with no success.