fix(cdk/portal): not marked as attached when going through specific portal methods (#22372)

Fixes that the `DomPortalOutlet.hasAttached` doesn't return the correct information when the portal has been attached through the specific portal methods (e.g. `attachComponentPortal`, `attachTemplatePortal`).

Fixes #22370.

Author: crisbeto

src/cdk/portal/dom-portal-outlet.ts

@@ -71,6 +71,7 @@ export class DomPortalOutlet extends BasePortalOutlet {
     // At this point the component has been instantiated, so we move it to the location in the DOM
     // where we want it to be rendered.
     this.outletElement.appendChild(this._getComponentRootNode(componentRef));
+    this._attachedPortal = portal;
 
     return componentRef;
   }
@@ -102,6 +103,8 @@ export class DomPortalOutlet extends BasePortalOutlet {
       }
     }));
 
+    this._attachedPortal = portal;
+
     // TODO(jelbourn): Return locals from view.
     return viewRef;
   }
@@ -130,6 +133,7 @@ export class DomPortalOutlet extends BasePortalOutlet {
 
     element.parentNode!.insertBefore(anchorNode, element);
     this.outletElement.appendChild(element);
+    this._attachedPortal = portal;
 
     super.setDisposeFn(() => {
       // We can't use `replaceWith` here because IE doesn't support it.

src/cdk/portal/portal-directives.ts

@@ -214,6 +214,7 @@ export class CdkPortalOutlet extends BasePortalOutlet implements OnInit, OnDestr
     portal.setAttachedHost(this);
     element.parentNode!.insertBefore(anchorNode, element);
     this._getRootNode().appendChild(element);
+    this._attachedPortal = portal;
 
     super.setDisposeFn(() => {
       if (anchorNode.parentNode) {

src/cdk/portal/portal.spec.ts

@@ -101,6 +101,7 @@ describe('Portals', () => {
           .not.toBe(initialParent, 'Expected portal to be out of the initial parent on attach.');
       expect(hostContainer.contains(innerContent))
           .toBe(true, 'Expected content to be inside the outlet on attach.');
+      expect(testAppComponent.portalOutlet.hasAttached()).toBe(true);
 
       testAppComponent.selectedPortal = undefined;
       fixture.detectChanges();
@@ -109,6 +110,7 @@ describe('Portals', () => {
           .toBe(initialParent, 'Expected portal to be back inside initial parent on detach.');
       expect(hostContainer.contains(innerContent))
           .toBe(false, 'Expected content to be removed from outlet on detach.');
+      expect(testAppComponent.portalOutlet.hasAttached()).toBe(false);
     });
 
     it('should throw when trying to load an element without a parent into a DOM portal', () => {
@@ -624,6 +626,30 @@ describe('Portals', () => {
       expect(() => host.detach()).not.toThrow();
     });
 
+    it('should set hasAttached when the various portal types are attached', () => {
+      const fixture = TestBed.createComponent(PortalTestApp);
+      fixture.detectChanges();
+      const viewContainerRef = fixture.componentInstance.viewContainerRef;
+
+      expect(host.hasAttached()).toBe(false);
+
+      host.attachComponentPortal(new ComponentPortal(PizzaMsg, viewContainerRef));
+      expect(host.hasAttached()).toBe(true);
+
+      host.detach();
+      expect(host.hasAttached()).toBe(false);
+
+      host.attachTemplatePortal(
+          new TemplatePortal(fixture.componentInstance.templateRef, viewContainerRef));
+      expect(host.hasAttached()).toBe(true);
+
+      host.detach();
+      expect(host.hasAttached()).toBe(false);
+
+      host.attachDomPortal(new DomPortal(fixture.componentInstance.domPortalContent));
+      expect(host.hasAttached()).toBe(true);
+    });
+
   });
 });
 
@@ -730,7 +756,7 @@ class PortalTestApp {
   fruits = ['Apple', 'Pineapple', 'Durian'];
   attachedSpy = jasmine.createSpy('attached spy');
 
-  constructor(public injector: Injector) { }
+  constructor(public viewContainerRef: ViewContainerRef, public injector: Injector) { }
 
   get cakePortal() {
     return this.portals.first;