From 1ff1792642ded576a5d2d896ee909715bfdd7059 Mon Sep 17 00:00:00 2001
From: Alex Rickabaugh <alx+alxhub@alxandria.net>
Date: Tue, 10 Nov 2015 10:40:33 -0800
Subject: [PATCH] fix(core): Unload components when individually disposed.

---
 modules/angular2/src/core/application_ref.ts  | 39 +++++++++++++++----
 .../angular2/test/core/application_spec.ts    | 19 ++++++++-
 2 files changed, 49 insertions(+), 9 deletions(-)

diff --git a/modules/angular2/src/core/application_ref.ts b/modules/angular2/src/core/application_ref.ts
index 8d54589bbc..aa7514b9a1 100644
--- a/modules/angular2/src/core/application_ref.ts
+++ b/modules/angular2/src/core/application_ref.ts
@@ -69,10 +69,15 @@ function _componentProviders(appComponentType: Type): Array<Type | Provider | an
     provide(APP_COMPONENT, {useValue: appComponentType}),
     provide(APP_COMPONENT_REF_PROMISE,
             {
-              useFactory: (dynamicComponentLoader, injector: Injector) => {
+              useFactory: (dynamicComponentLoader: DynamicComponentLoader, appRef: ApplicationRef_,
+                           injector: Injector) => {
+                // Save the ComponentRef for disposal later.
+                var ref: ComponentRef;
                 // TODO(rado): investigate whether to support providers on root component.
-                return dynamicComponentLoader.loadAsRoot(appComponentType, null, injector)
+                return dynamicComponentLoader.loadAsRoot(appComponentType, null, injector,
+                                                         () => { appRef._unloadComponent(ref); })
                     .then((componentRef) => {
+                      ref = componentRef;
                       if (isPresent(componentRef.location.nativeElement)) {
                         injector.get(TestabilityRegistry)
                             .registerApplication(componentRef.location.nativeElement,
@@ -81,7 +86,7 @@ function _componentProviders(appComponentType: Type): Array<Type | Provider | an
                       return componentRef;
                     });
               },
-              deps: [DynamicComponentLoader, Injector]
+              deps: [DynamicComponentLoader, ApplicationRef, Injector]
             }),
     provide(appComponentType,
             {
@@ -394,6 +399,10 @@ export class ApplicationRef_ extends ApplicationRef {
     this._changeDetectorRefs.push(changeDetector);
   }
 
+  unregisterChangeDetector(changeDetector: ChangeDetectorRef): void {
+    ListWrapper.remove(this._changeDetectorRefs, changeDetector);
+  }
+
   bootstrap(componentType: Type,
             providers?: Array<Type | Provider | any[]>): Promise<ComponentRef> {
     var completer = PromiseWrapper.completer();
@@ -408,12 +417,8 @@ export class ApplicationRef_ extends ApplicationRef {
         var injector: Injector = this._injector.resolveAndCreateChild(componentProviders);
         var compRefToken: Promise<ComponentRef> = injector.get(APP_COMPONENT_REF_PROMISE);
         var tick = (componentRef) => {
-          var appChangeDetector = internalView(componentRef.hostView).changeDetector;
-          this._changeDetectorRefs.push(appChangeDetector.ref);
-          this.tick();
+          this._loadComponent(componentRef);
           completer.resolve(componentRef);
-          this._rootComponents.push(componentRef);
-          this._bootstrapListeners.forEach((listener) => listener(componentRef));
         };
 
         var tickResult = PromiseWrapper.then(compRefToken, tick);
@@ -429,6 +434,24 @@ export class ApplicationRef_ extends ApplicationRef {
     return completer.promise;
   }
 
+  /** @internal */
+  _loadComponent(ref): void {
+    var appChangeDetector = internalView(ref.hostView).changeDetector;
+    this._changeDetectorRefs.push(appChangeDetector.ref);
+    this.tick();
+    this._rootComponents.push(ref);
+    this._bootstrapListeners.forEach((listener) => listener(ref));
+  }
+
+  /** @internal */
+  _unloadComponent(ref): void {
+    if (!ListWrapper.contains(this._rootComponents, ref)) {
+      return;
+    }
+    this.unregisterChangeDetector(internalView(ref.hostView).changeDetector.ref);
+    ListWrapper.remove(this._rootComponents, ref);
+  }
+
   get injector(): Injector { return this._injector; }
 
   get zone(): NgZone { return this._zone; }
diff --git a/modules/angular2/test/core/application_spec.ts b/modules/angular2/test/core/application_spec.ts
index af3ecd1a4c..1ed6f3a5db 100644
--- a/modules/angular2/test/core/application_spec.ts
+++ b/modules/angular2/test/core/application_spec.ts
@@ -12,7 +12,8 @@ import {
 } from 'angular2/testing_internal';
 import {IS_DART, isPresent, stringify} from 'angular2/src/facade/lang';
 import {bootstrap} from 'angular2/bootstrap';
-import {ApplicationRef} from 'angular2/src/core/application_ref';
+import {platform, applicationDomProviders} from 'angular2/src/core/application_common';
+import {applicationCommonProviders, ApplicationRef} from 'angular2/src/core/application_ref';
 import {Component, Directive, View} from 'angular2/core';
 import {DOM} from 'angular2/src/core/dom/dom_adapter';
 import {DOCUMENT} from 'angular2/render';
@@ -21,6 +22,7 @@ import {provide, Inject, Injector} from 'angular2/core';
 import {ExceptionHandler} from 'angular2/src/facade/exceptions';
 import {Testability, TestabilityRegistry} from 'angular2/src/core/testability/testability';
 import {ComponentRef_} from "angular2/src/core/linker/dynamic_component_loader";
+import {compilerProviders} from 'angular2/src/compiler/compiler';
 
 @Component({selector: 'hello-app'})
 @View({template: '{{greeting}} world!'})
@@ -161,6 +163,21 @@ export function main() {
                async.done();
              });
        }));
+    it('should unregister change detectors when components are disposed',
+       inject([AsyncTestCompleter], (async) => {
+         var app = platform().application([
+           applicationCommonProviders(),
+           applicationDomProviders(),
+           compilerProviders(),
+           testProviders
+         ]);
+         app.bootstrap(HelloRootCmp)
+             .then((ref) => {
+               ref.dispose();
+               expect(() => app.tick()).not.toThrow();
+               async.done();
+             });
+       }));
 
     it("should make the provided bindings available to the application component",
        inject([AsyncTestCompleter], (async) => {