feat(elements): injector create (#22413)

PR Close #22413

aio/scripts/_payload-limits.json

@@ -4,7 +4,7 @@
       "uncompressed": {
         "inline": 2062,
         "main": 467103,
-        "polyfills": 55349,
+        "polyfills": 54292,
         "embedded": 71711,
         "prettify": 14888
       }

aio/src/app/custom-elements/code/code-example.component.spec.ts

@@ -30,7 +30,7 @@ describe('CodeExampleComponent', () => {
   });
 
   it('should be able to capture the code snippet provided in content', () => {
-    expect(codeExampleComponent.code.trim()).toBe(`const foo = "bar";`);
+    expect(codeExampleComponent.aioCode.code.trim()).toBe(`const foo = "bar";`);
   });
 
   it('should change aio-code classes based on title presence', () => {

aio/src/app/custom-elements/code/code-example.component.ts

@@ -34,8 +34,6 @@ import { CodeComponent } from './code.component';
 export class CodeExampleComponent implements AfterViewInit {
   classes: {};
 
-  code: string;
-
   @Input() language: string;
 
   @Input() linenums: string;

aio/src/app/custom-elements/elements-loader.spec.ts

@@ -9,8 +9,6 @@ import {TestBed, fakeAsync, tick} from '@angular/core/testing';
 import { ElementsLoader } from './elements-loader';
 import { ELEMENT_MODULE_PATHS_TOKEN, WithCustomElementComponent } from './element-registry';
 
-const actualCustomElements = window.customElements;
-
 class FakeComponentFactory extends ComponentFactory<any> {
   selector: string;
   componentType: Type<any>;
@@ -29,21 +27,26 @@ class FakeComponentFactory extends ComponentFactory<any> {
 }
 
 const FAKE_COMPONENT_FACTORIES = new Map([
-  ['element-a-module-path', new FakeComponentFactory('element-a-input')]
+  ['element-a-module-path', new FakeComponentFactory('element-a-input')],
+  ['element-b-module-path', new FakeComponentFactory('element-b-input')],
 ]);
 
-fdescribe('ElementsLoader', () => {
+describe('ElementsLoader', () => {
   let elementsLoader: ElementsLoader;
   let injectedModuleRef: NgModuleRef<any>;
-  let fakeCustomElements;
+  let actualCustomElementsDefine;
+  let fakeCustomElementsDefine;
 
   // ElementsLoader uses the window's customElements API. Provide a fake for this test.
   beforeEach(() => {
-    fakeCustomElements = jasmine.createSpyObj('customElements', ['define', 'whenDefined']);
+    actualCustomElementsDefine = window.customElements.define;
-    window.customElements = fakeCustomElements;
+
+    fakeCustomElementsDefine = jasmine.createSpy('define');
+
+    window.customElements.define = fakeCustomElementsDefine;
   });
   afterEach(() => {
-    window.customElements = actualCustomElements;
+    window.customElements.define = actualCustomElementsDefine;
   });
 
   beforeEach(() => {
@@ -52,7 +55,8 @@ fdescribe('ElementsLoader', () => {
         ElementsLoader,
         { provide: NgModuleFactoryLoader, useClass: FakeModuleFactoryLoader },
         { provide: ELEMENT_MODULE_PATHS_TOKEN, useValue: new Map([
-          ['element-a-selector', 'element-a-module-path']
+          ['element-a-selector', 'element-a-module-path'],
+          ['element-b-selector', 'element-b-module-path']
         ])},
       ]
     });
@@ -71,7 +75,7 @@ fdescribe('ElementsLoader', () => {
     elementsLoader.loadContainingCustomElements(hostEl);
     tick();
 
-    const defineArgs = fakeCustomElements.define.calls.argsFor(0);
+    const defineArgs = fakeCustomElementsDefine.calls.argsFor(0);
     expect(defineArgs[0]).toBe('element-a-selector');
 
     // Verify the right component was loaded/created
@@ -80,6 +84,30 @@ fdescribe('ElementsLoader', () => {
     expect(elementsLoader.elementsToLoad.has('element-a-selector')).toBeFalsy();
   }));
 
+  it('should be able to register multiple elements', fakeAsync(() => {
+    // Verify that the elements loader considered `element-a-selector` to be unregistered.
+    expect(elementsLoader.elementsToLoad.has('element-a-selector')).toBeTruthy();
+
+    const hostEl = document.createElement('div');
+    hostEl.innerHTML = `
+      <element-a-selector></element-a-selector>
+      <element-b-selector></element-b-selector>
+    `;
+
+    elementsLoader.loadContainingCustomElements(hostEl);
+    tick();
+
+    const defineElementA = fakeCustomElementsDefine.calls.argsFor(0);
+    expect(defineElementA[0]).toBe('element-a-selector');
+    expect(defineElementA[1].observedAttributes[0]).toBe('element-a-input');
+    expect(elementsLoader.elementsToLoad.has('element-a-selector')).toBeFalsy();
+
+    const defineElementB = fakeCustomElementsDefine.calls.argsFor(1);
+    expect(defineElementB[0]).toBe('element-b-selector');
+    expect(defineElementB[1].observedAttributes[0]).toBe('element-b-input');
+    expect(elementsLoader.elementsToLoad.has('element-b-selector')).toBeFalsy();
+  }));
+
   it('should only register an element one time', fakeAsync(() => {
     const hostEl = document.createElement('div');
     hostEl.innerHTML = `<element-a-selector></element-a-selector>`;

aio/src/app/layout/doc-viewer/doc-viewer.component.spec.ts

@@ -8,14 +8,14 @@ import { FILE_NOT_FOUND_ID, FETCHING_ERROR_ID } from 'app/documents/document.ser
 import { Logger } from 'app/shared/logger.service';
 import { CustomElementsModule } from 'app/custom-elements/custom-elements.module';
 import { TocService } from 'app/shared/toc.service';
+import { ElementsLoader } from 'app/custom-elements/elements-loader';
 import {
-  MockTitle, MockTocService, ObservableWithSubscriptionSpies,
+MockTitle, MockTocService, ObservableWithSubscriptionSpies,
-  TestDocViewerComponent, TestModule, TestParentComponent
+TestDocViewerComponent, TestModule, TestParentComponent, MockElementsLoader
 } from 'testing/doc-viewer-utils';
 import { MockLogger } from 'testing/logger.service';
 import { DocViewerComponent, NO_ANIMATIONS } from './doc-viewer.component';
 
-
 describe('DocViewerComponent', () => {
   let parentFixture: ComponentFixture<TestParentComponent>;
   let parentComponent: TestParentComponent;
@@ -24,7 +24,7 @@ describe('DocViewerComponent', () => {
 
   beforeEach(() => {
     TestBed.configureTestingModule({
-      imports: [TestModule, CustomElementsModule],
+      imports: [CustomElementsModule, TestModule],
     });
 
     parentFixture = TestBed.createComponent(TestParentComponent);
@@ -294,12 +294,16 @@ describe('DocViewerComponent', () => {
   describe('#render()', () => {
     let prepareTitleAndTocSpy: jasmine.Spy;
     let swapViewsSpy: jasmine.Spy;
+    let loadElementsSpy: jasmine.Spy;
 
     const doRender = (contents: string | null, id = 'foo') =>
       new Promise<void>((resolve, reject) =>
         docViewer.render({contents, id}).subscribe(resolve, reject));
 
     beforeEach(() => {
+      const elementsLoader = TestBed.get(ElementsLoader) as MockElementsLoader;
+      loadElementsSpy =
+          elementsLoader.loadContainingCustomElements.and.returnValue(of([]));
       prepareTitleAndTocSpy = spyOn(docViewer, 'prepareTitleAndToc');
       swapViewsSpy = spyOn(docViewer, 'swapViews').and.returnValue(of(undefined));
     });
@@ -333,7 +337,7 @@ describe('DocViewerComponent', () => {
         expect(docViewerEl.textContent).toBe('');
       });
 
-      it('should prepare the title and ToC', async () => {
+      it('should prepare the title and ToC (before embedding components)', async () => {
         prepareTitleAndTocSpy.and.callFake((targetEl: HTMLElement, docId: string) => {
           expect(targetEl.innerHTML).toBe('Some content');
           expect(docId).toBe('foo');
@@ -342,6 +346,7 @@ describe('DocViewerComponent', () => {
         await doRender('Some content', 'foo');
 
         expect(prepareTitleAndTocSpy).toHaveBeenCalledTimes(1);
+        expect(prepareTitleAndTocSpy).toHaveBeenCalledBefore(loadElementsSpy);
       });
 
       it('should set the title and ToC (after the content has been set)', async () => {
@@ -384,6 +389,39 @@ describe('DocViewerComponent', () => {
       });
     });
 
+    describe('(embedding components)', () => {
+      it('should embed components', async () => {
+        await doRender('Some content');
+        expect(loadElementsSpy).toHaveBeenCalledTimes(1);
+        expect(loadElementsSpy).toHaveBeenCalledWith(docViewer.nextViewContainer);
+      });
+
+      it('should attempt to embed components even if the document is empty', async () => {
+        await doRender('');
+        await doRender(null);
+
+        expect(loadElementsSpy).toHaveBeenCalledTimes(2);
+        expect(loadElementsSpy.calls.argsFor(0)).toEqual([docViewer.nextViewContainer]);
+        expect(loadElementsSpy.calls.argsFor(1)).toEqual([docViewer.nextViewContainer]);
+      });
+
+      it('should unsubscribe from the previous "embed" observable when unsubscribed from', () => {
+        const obs = new ObservableWithSubscriptionSpies();
+        loadElementsSpy.and.returnValue(obs);
+
+        const renderObservable = docViewer.render({contents: 'Some content', id: 'foo'});
+        const subscription = renderObservable.subscribe();
+
+        expect(obs.subscribeSpy).toHaveBeenCalledTimes(1);
+        expect(obs.unsubscribeSpies[0]).not.toHaveBeenCalled();
+
+        subscription.unsubscribe();
+
+        expect(obs.subscribeSpy).toHaveBeenCalledTimes(1);
+        expect(obs.unsubscribeSpies[0]).toHaveBeenCalledTimes(1);
+      });
+    });
+
     describe('(swapping views)', () => {
       it('should still swap the views if the document is empty', async () => {
         await doRender('');
@@ -444,6 +482,25 @@ describe('DocViewerComponent', () => {
         expect(TestBed.get(Meta).addTag).toHaveBeenCalledWith({ name: 'robots', content: 'noindex' });
       });
 
+      it('when `EmbedComponentsService.embedInto()` fails', async () => {
+        const error = Error('Typical `embedInto()` error');
+        loadElementsSpy.and.callFake(() => {
+          expect(docViewer.nextViewContainer.innerHTML).not.toBe('');
+          throw error;
+        });
+
+        await doRender('Some content', 'bar');
+
+        expect(prepareTitleAndTocSpy).toHaveBeenCalledTimes(1);
+        expect(loadElementsSpy).toHaveBeenCalledTimes(1);
+        expect(swapViewsSpy).not.toHaveBeenCalled();
+        expect(docViewer.nextViewContainer.innerHTML).toBe('');
+        expect(logger.output.error).toEqual([
+          [`[DocViewer] Error preparing document 'bar': ${error.stack}`],
+        ]);
+        expect(TestBed.get(Meta).addTag).toHaveBeenCalledWith({ name: 'googlebot', content: 'noindex' });
+        expect(TestBed.get(Meta).addTag).toHaveBeenCalledWith({ name: 'robots', content: 'noindex' });
+      });
 
       it('when `swapViews()` fails', async () => {
         const error = Error('Typical `swapViews()` error');
@@ -486,13 +543,24 @@ describe('DocViewerComponent', () => {
     });
 
     describe('(events)', () => {
-      it('should emit `docReady`', async () => {
+      it('should emit `docReady` after loading elements', async () => {
         const onDocReadySpy = jasmine.createSpy('onDocReady');
         docViewer.docReady.subscribe(onDocReadySpy);
 
         await doRender('Some content');
 
         expect(onDocReadySpy).toHaveBeenCalledTimes(1);
+        expect(loadElementsSpy).toHaveBeenCalledBefore(onDocReadySpy);
+      });
+
+      it('should emit `docReady` before swapping views', async () => {
+        const onDocReadySpy = jasmine.createSpy('onDocReady');
+        docViewer.docReady.subscribe(onDocReadySpy);
+
+        await doRender('Some content');
+
+        expect(onDocReadySpy).toHaveBeenCalledTimes(1);
+        expect(onDocReadySpy).toHaveBeenCalledBefore(swapViewsSpy);
       });
 
       it('should emit `docRendered` after swapping views', async () => {

aio/src/index.html

@@ -110,6 +110,15 @@
     }
   </script>
 
+  <script>
+    // Custom elements should always rely on the polyfill to avoid having to include a shim that
+    // handles downleveled ES2015 classes. Especially since that shim would break on IE11 which
+    // can't even parse such code.
+    if (window.customElements) {
+      window.customElements['forcePolyfill'] = true;
+    }
+  </script>
+
 </head>
 <body>
 

aio/src/polyfills.ts

@@ -33,9 +33,6 @@ import './environments/environment';
 /** Add support for window.customElements */
 import '@webcomponents/custom-elements/custom-elements.min';
 
-/** Required for custom elements for apps building to es5. */
-import '@webcomponents/custom-elements/src/native-shim';
-
 /** ALL Firefox browsers require the following to support `@angular/animation`. **/
 // import 'web-animations-js';  // Run `npm install --save web-animations-js`.
 

aio/src/testing/doc-viewer-utils.ts

@@ -8,6 +8,7 @@ import { DocViewerComponent } from 'app/layout/doc-viewer/doc-viewer.component';
 import { Logger } from 'app/shared/logger.service';
 import { TocService } from 'app/shared/toc.service';
 import { MockLogger } from 'testing/logger.service';
+import { ElementsLoader } from 'app/custom-elements/elements-loader';
 
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
@@ -54,6 +55,11 @@ export class MockTocService {
   reset = jasmine.createSpy('TocService#reset');
 }
 
+export class MockElementsLoader {
+  loadContainingCustomElements =
+      jasmine.createSpy('MockElementsLoader#loadContainingCustomElements');
+}
+
 @NgModule({
   declarations: [
     DocViewerComponent,
@@ -64,6 +70,7 @@ export class MockTocService {
     { provide: Title, useClass: MockTitle },
     { provide: Meta, useClass: MockMeta },
     { provide: TocService, useClass: MockTocService },
+    { provide: ElementsLoader, useClass: MockElementsLoader },
   ],
 })
 export class TestModule { }

packages/compiler/test/schema/schema_extractor.ts

@@ -205,6 +205,13 @@ function extractProperties(
 function extractName(type: Function): string|null {
   let name = type['name'];
 
+  // The polyfill @webcomponents/custom-element/src/native-shim.js overrides the
+  // window.HTMLElement and does not have the name property. Check if this is the
+  // case and if so, set the name manually.
+  if (name === '' && type === HTMLElement) {
+    name = 'HTMLElement';
+  }
+
   switch (name) {
     // see https://www.w3.org/TR/html5/index.html
     // TODO(vicb): generate this map from all the element types

packages/elements/src/component-factory-strategy.ts

@@ -6,29 +6,35 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {ApplicationRef, ComponentFactory, ComponentRef, EventEmitter, Injector, OnChanges, SimpleChange, SimpleChanges} from '@angular/core';
+import {ApplicationRef, ComponentFactory, ComponentFactoryResolver, ComponentRef, EventEmitter, Injector, OnChanges, SimpleChange, SimpleChanges, Type} from '@angular/core';
 import {Observable} from 'rxjs/Observable';
 import {merge} from 'rxjs/observable/merge';
 import {map} from 'rxjs/operator/map';
 
 import {NgElementStrategy, NgElementStrategyEvent, NgElementStrategyFactory} from './element-strategy';
 import {extractProjectableNodes} from './extract-projectable-nodes';
-import {camelToDashCase, isFunction, scheduler, strictEquals} from './utils';
+import {isFunction, scheduler, strictEquals} from './utils';
 
 /** Time in milliseconds to wait before destroying the component ref when disconnected. */
 const DESTROY_DELAY = 10;
 
 /**
- * Factory that creates new ComponentFactoryNgElementStrategy instances with the strategy factory's
+ * Factory that creates new ComponentNgElementStrategy instance. Gets the component factory with the
- * injector. A new strategy instance is created with the provided component factory which will
+ * constructor's injector's factory resolver and passes that factory to each strategy.
- * create its components on connect.
  *
  * @experimental
  */
-export class ComponentFactoryNgElementStrategyFactory implements NgElementStrategyFactory {
+export class ComponentNgElementStrategyFactory implements NgElementStrategyFactory {
-  constructor(private componentFactory: ComponentFactory<any>, private injector: Injector) {}
+  componentFactory: ComponentFactory<any>;
 
-  create() { return new ComponentFactoryNgElementStrategy(this.componentFactory, this.injector); }
+  constructor(private component: Type<any>, private injector: Injector) {
+    this.componentFactory =
+        injector.get(ComponentFactoryResolver).resolveComponentFactory(component);
+  }
+
+  create(injector: Injector) {
+    return new ComponentNgElementStrategy(this.componentFactory, injector);
+  }
 }
 
 /**
@@ -37,12 +43,12 @@ export class ComponentFactoryNgElementStrategyFactory implements NgElementStrate
  *
  * @experimental
  */
-export class ComponentFactoryNgElementStrategy implements NgElementStrategy {
+export class ComponentNgElementStrategy implements NgElementStrategy {
   /** Merged stream of the component's output events. */
   events: Observable<NgElementStrategyEvent>;
 
   /** Reference to the component that was created on connect. */
-  private componentRef: ComponentRef<any>;
+  private componentRef: ComponentRef<any>|null;
 
   /** Changes that have been made to the component ref since the last time onChanges was called. */
   private inputChanges: SimpleChanges|null = null;
@@ -96,6 +102,7 @@ export class ComponentFactoryNgElementStrategy implements NgElementStrategy {
     this.scheduledDestroyFn = scheduler.schedule(() => {
       if (this.componentRef) {
         this.componentRef !.destroy();
+        this.componentRef = null;
       }
     }, DESTROY_DELAY);
   }

packages/elements/src/element-strategy.ts

@@ -5,7 +5,7 @@
  * Use of this source code is governed by an MIT-style license that can be
  * found in the LICENSE file at https://angular.io/license
  */
-import {ComponentFactory} from '@angular/core';
+import {ComponentFactory, Injector} from '@angular/core';
 import {Observable} from 'rxjs/Observable';
 
 /**
@@ -38,4 +38,7 @@ export interface NgElementStrategy {
  *
  * @experimental
  */
-export interface NgElementStrategyFactory { create(): NgElementStrategy; }
+export interface NgElementStrategyFactory {
+  /** Creates a new instance to be used for an NgElement. */
+  create(injector: Injector): NgElementStrategy;
+}

packages/elements/src/ng-element-constructor.ts

@@ -6,12 +6,12 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {ComponentFactoryResolver, Injector, Type} from '@angular/core';
+import {Injector, Type} from '@angular/core';
 import {Subscription} from 'rxjs/Subscription';
 
-import {ComponentFactoryNgElementStrategyFactory} from './component-factory-strategy';
+import {ComponentNgElementStrategyFactory} from './component-factory-strategy';
 import {NgElementStrategy, NgElementStrategyFactory} from './element-strategy';
-import {camelToDashCase, createCustomEvent} from './utils';
+import {createCustomEvent, getComponentInputs, getDefaultAttributeToPropertyInputs} from './utils';
 
 /**
  * Class constructor based on an Angular Component to be used for custom element registration.
@@ -21,7 +21,7 @@ import {camelToDashCase, createCustomEvent} from './utils';
 export interface NgElementConstructor<P> {
   readonly observedAttributes: string[];
 
-  new (): NgElement&WithProperties<P>;
+  new (injector: Injector): NgElement&WithProperties<P>;
 }
 
 /**
@@ -50,30 +50,19 @@ export type WithProperties<P> = {
 };
 
 /**
- * Initialization configuration for the NgElementConstructor. Provides the strategy factory
+ * Initialization configuration for the NgElementConstructor which contains the injector to be used
- * that produces a strategy for each instantiated element. Additionally, provides a function
+ * for retrieving the component's factory as well as the default context for the component. May
- * that takes the component factory and provides a map of which attributes should be observed on
+ * provide a custom strategy factory to be used instead of the default. May provide a custom mapping
- * the element and which property they are associated with.
+ * of attribute names to component inputs.
  *
  * @experimental
  */
 export interface NgElementConfig {
   injector: Injector;
   strategyFactory?: NgElementStrategyFactory;
-  propertyInputs?: string[];
   attributeToPropertyInputs?: {[key: string]: string};
 }
 
-/** Gets a map of default set of attributes to observe and the properties they affect. */
-function getDefaultAttributeToPropertyInputs(inputs: {propName: string, templateName: string}[]) {
-  const attributeToPropertyInputs: {[key: string]: string} = {};
-  inputs.forEach(({propName, templateName}) => {
-    attributeToPropertyInputs[camelToDashCase(templateName)] = propName;
-  });
-
-  return attributeToPropertyInputs;
-}
-
 /**
  * @whatItDoes Creates a custom element class based on an Angular Component. Takes a configuration
  * that provides initialization information to the created class. E.g. the configuration's injector
@@ -90,13 +79,10 @@ function getDefaultAttributeToPropertyInputs(inputs: {propName: string, template
  */
 export function createNgElementConstructor<P>(
     component: Type<any>, config: NgElementConfig): NgElementConstructor<P> {
-  const componentFactoryResolver =
+  const inputs = getComponentInputs(component, config.injector);
-      config.injector.get(ComponentFactoryResolver) as ComponentFactoryResolver;
-  const componentFactory = componentFactoryResolver.resolveComponentFactory(component);
-  const inputs = componentFactory.inputs;
 
-  const defaultStrategyFactory = config.strategyFactory ||
+  const strategyFactory =
-      new ComponentFactoryNgElementStrategyFactory(componentFactory, config.injector);
+      config.strategyFactory || new ComponentNgElementStrategyFactory(component, config.injector);
 
   const attributeToPropertyInputs =
       config.attributeToPropertyInputs || getDefaultAttributeToPropertyInputs(inputs);
@@ -104,13 +90,9 @@ export function createNgElementConstructor<P>(
   class NgElementImpl extends NgElement {
     static readonly observedAttributes = Object.keys(attributeToPropertyInputs);
 
-    constructor(strategyFactoryOverride?: NgElementStrategyFactory) {
+    constructor(injector?: Injector) {
       super();
-
+      this.ngElementStrategy = strategyFactory.create(injector || config.injector);
-      // Use the constructor's strategy factory override if it is present, otherwise default to
-      // the config's factory.
-      const strategyFactory = strategyFactoryOverride || defaultStrategyFactory;
-      this.ngElementStrategy = strategyFactory.create();
     }
 
     attributeChangedCallback(
@@ -120,14 +102,6 @@ export function createNgElementConstructor<P>(
     }
 
     connectedCallback(): void {
-      // Take element attribute inputs and set them as inputs on the strategy
-      NgElementImpl.observedAttributes.forEach(attrName => {
-        const propName = attributeToPropertyInputs[attrName] !;
-        if (this.hasAttribute(attrName)) {
-          this.ngElementStrategy.setInputValue(propName, this.getAttribute(attrName) !);
-        }
-      });
-
       this.ngElementStrategy.connect(this);
 
       // Listen for events from the strategy and dispatch them as custom events
@@ -149,8 +123,7 @@ export function createNgElementConstructor<P>(
 
   // Add getters and setters to the prototype for each property input. If the config does not
   // contain property inputs, use all inputs by default.
-  const propertyInputs = config.propertyInputs || inputs.map(({propName}) => propName);
+  inputs.map(({propName}) => propName).forEach(property => {
-  propertyInputs.forEach(property => {
     Object.defineProperty(NgElementImpl.prototype, property, {
       get: function() { return this.ngElementStrategy.getInputValue(property); },
       set: function(newValue: any) { this.ngElementStrategy.setInputValue(property, newValue); },

packages/elements/src/utils.ts

@@ -5,8 +5,7 @@
  * Use of this source code is governed by an MIT-style license that can be
  * found in the LICENSE file at https://angular.io/license
  */
-
+import {ComponentFactoryResolver, Injector, Type} from '@angular/core';
-import {Type} from '@angular/core';
 
 const elProto = Element.prototype as any;
 const matches = elProto.matches || elProto.matchesSelector || elProto.mozMatchesSelector ||
@@ -101,3 +100,25 @@ export function matchesSelector(element: Element, selector: string): boolean {
 export function strictEquals(value1: any, value2: any): boolean {
   return value1 === value2 || (value1 !== value1 && value2 !== value2);
 }
+
+/** Gets a map of default set of attributes to observe and the properties they affect. */
+export function getDefaultAttributeToPropertyInputs(
+    inputs: {propName: string, templateName: string}[]) {
+  const attributeToPropertyInputs: {[key: string]: string} = {};
+  inputs.forEach(({propName, templateName}) => {
+    attributeToPropertyInputs[camelToDashCase(templateName)] = propName;
+  });
+
+  return attributeToPropertyInputs;
+}
+
+/**
+ * Gets a component's set of inputs. Uses the injector to get the component factory where the inputs
+ * are defined.
+ */
+export function getComponentInputs(
+    component: Type<any>, injector: Injector): {propName: string, templateName: string}[] {
+  const componentFactoryResolver: ComponentFactoryResolver = injector.get(ComponentFactoryResolver);
+  const componentFactory = componentFactoryResolver.resolveComponentFactory(component);
+  return componentFactory.inputs;
+}

packages/elements/test/component-factory-strategy_spec.ts

@@ -10,12 +10,12 @@ import {ComponentFactory, ComponentRef, Injector, NgModuleRef, SimpleChange, Sim
 import {fakeAsync, tick} from '@angular/core/testing';
 import {Subject} from 'rxjs/Subject';
 
-import {ComponentFactoryNgElementStrategy, ComponentFactoryNgElementStrategyFactory} from '../src/component-factory-strategy';
+import {ComponentNgElementStrategy, ComponentNgElementStrategyFactory} from '../src/component-factory-strategy';
 import {NgElementStrategyEvent} from '../src/element-strategy';
 
 describe('ComponentFactoryNgElementStrategy', () => {
   let factory: FakeComponentFactory;
-  let strategy: ComponentFactoryNgElementStrategy;
+  let strategy: ComponentNgElementStrategy;
 
   let injector: any;
   let componentRef: any;
@@ -25,22 +25,26 @@ describe('ComponentFactoryNgElementStrategy', () => {
     factory = new FakeComponentFactory();
     componentRef = factory.componentRef;
 
-    injector = jasmine.createSpyObj('injector', ['get']);
     applicationRef = jasmine.createSpyObj('applicationRef', ['attachView']);
-    injector.get.and.returnValue(applicationRef);
 
-    strategy = new ComponentFactoryNgElementStrategy(factory, injector);
+    strategy = new ComponentNgElementStrategy(factory, injector);
   });
 
   it('should create a new strategy from the factory', () => {
-    const strategyFactory = new ComponentFactoryNgElementStrategyFactory(factory, injector);
+    const factoryResolver = jasmine.createSpyObj('factoryResolver', ['resolveComponentFactory']);
-    expect(strategyFactory.create()).toBeTruthy();
+    factoryResolver.resolveComponentFactory.and.returnValue(factory);
+    injector = jasmine.createSpyObj('injector', ['get']);
+    injector.get.and.returnValue(factoryResolver);
+
+    const strategyFactory = new ComponentNgElementStrategyFactory(FakeComponent, injector);
+    expect(strategyFactory.create(injector)).toBeTruthy();
   });
 
   describe('after connected', () => {
     beforeEach(() => {
       // Set up an initial value to make sure it is passed to the component
       strategy.setInputValue('fooFoo', 'fooFoo-1');
+      injector.get.and.returnValue(applicationRef);
       strategy.connect(document.createElement('div'));
     });
 
@@ -95,7 +99,7 @@ describe('ComponentFactoryNgElementStrategy', () => {
     it('should not detect changes', fakeAsync(() => {
          strategy.setInputValue('fooFoo', 'fooFoo-1');
          tick(16);  // scheduler waits 16ms if RAF is unavailable
-         expect(componentRef.changeDetectorRef.detectChanges).toHaveBeenCalledTimes(0);
+         expect(componentRef.changeDetectorRef.detectChanges).not.toHaveBeenCalled();
        }));
   });
 

packages/elements/test/ng-element-constructor_spec.ts

@@ -51,7 +51,7 @@ if (typeof customElements !== 'undefined') {
     });
 
     it('should send input values from attributes when connected', () => {
-      const element = new NgElementCtor();
+      const element = new NgElementCtor(injector);
       element.setAttribute('foo-foo', 'value-foo-foo');
       element.setAttribute('barbar', 'value-barbar');
       element.connectedCallback();
@@ -62,7 +62,7 @@ if (typeof customElements !== 'undefined') {
     });
 
     it('should listen to output events after connected', () => {
-      const element = new NgElementCtor();
+      const element = new NgElementCtor(injector);
       element.connectedCallback();
 
       let eventValue: any = null;
@@ -73,7 +73,7 @@ if (typeof customElements !== 'undefined') {
     });
 
     it('should not listen to output events after disconnected', () => {
-      const element = new NgElementCtor();
+      const element = new NgElementCtor(injector);
       element.connectedCallback();
       element.disconnectedCallback();
       expect(strategy.disconnectCalled).toBe(true);
@@ -86,7 +86,7 @@ if (typeof customElements !== 'undefined') {
     });
 
     it('should properly set getters/setters on the element', () => {
-      const element = new NgElementCtor();
+      const element = new NgElementCtor(injector);
       element.fooFoo = 'foo-foo-value';
       element.barBar = 'barBar-value';
 
@@ -104,29 +104,26 @@ if (typeof customElements !== 'undefined') {
         NgElementCtorWithChangedAttr = createNgElementConstructor(TestComponent, {
           injector,
           strategyFactory,
-          propertyInputs: ['prop1', 'prop2'],
+          attributeToPropertyInputs: {'attr-1': 'fooFoo', 'attr-2': 'barbar'}
-          attributeToPropertyInputs: {'attr-1': 'prop1', 'attr-2': 'prop2'}
         });
 
         customElements.define('test-element-with-changed-attributes', NgElementCtorWithChangedAttr);
       });
 
-      beforeEach(() => { element = new NgElementCtorWithChangedAttr(); });
+      beforeEach(() => { element = new NgElementCtorWithChangedAttr(injector); });
 
       it('should affect which attributes are watched', () => {
         expect(NgElementCtorWithChangedAttr.observedAttributes).toEqual(['attr-1', 'attr-2']);
       });
 
       it('should send attribute values as inputs when connected', () => {
-        const element = new NgElementCtorWithChangedAttr();
+        const element = new NgElementCtorWithChangedAttr(injector);
         element.setAttribute('attr-1', 'value-1');
         element.setAttribute('attr-2', 'value-2');
-        element.setAttribute('attr-3', 'value-3');  // Made-up attribute
         element.connectedCallback();
 
-        expect(strategy.getInputValue('prop1')).toBe('value-1');
+        expect(strategy.getInputValue('fooFoo')).toBe('value-1');
-        expect(strategy.getInputValue('prop2')).toBe('value-2');
+        expect(strategy.getInputValue('barbar')).toBe('value-2');
-        expect(strategy.getInputValue('prop3')).not.toBe('value-3');
       });
     });
   });

scripts/ci/install.sh

@@ -56,7 +56,7 @@ if [[ ${TRAVIS} &&
   travisFoldStart "yarn-install.aio"
     (
       # HACK (don't submit with this): Build Angular
-      ./build.sh
+      ./build.sh --packages=core,elements --examples=false
 
       cd ${PROJECT_ROOT}/aio
       yarn install --frozen-lockfile --non-interactive

test-main.js

@@ -76,7 +76,7 @@ Promise
     .resolve()
 
     // Load browser-specific polyfills for custom elements.
-    // .then(function() { return loadCustomElementsPolyfills(); })
+    .then(function() { return loadCustomElementsPolyfills(); })
 
     // Load necessary testing packages.
     .then(function() {
@@ -151,29 +151,35 @@ function loadCustomElementsPolyfills() {
     Object.setPrototypeOf = setPrototypeOf;
   }
 
-  // The custom elements polyfill will patch `(HTML)Element` properties, including `innerHTML`:
+  // The custom elements polyfill will patch properties and methods on `(HTML)Element` and `Node`
-  // https://github.com/webcomponents/custom-elements/blob/32f043c3a5e5fc3e035342c0ef10c6786fa416d7/src/Patch/Element.js#L28-L78
+  // (among others), including `(HTML)Element#innerHTML` and `Node#removeChild()`:
-  // The patched `innerHTML` setter will try to traverse the DOM (via `nextSibling`), which leads to
+  // https://github.com/webcomponents/custom-elements/blob/4f7072c0dbda4beb505d16967acfffd33337b325/src/Patch/Element.js#L28-L73
-  // infinite loops when testing `HtmlSanitizer` with cloberred elements on browsers that do not
+  // https://github.com/webcomponents/custom-elements/blob/4f7072c0dbda4beb505d16967acfffd33337b325/src/Patch/Node.js#L105-L120
-  // support the `<template>` element:
+  // The patched `innerHTML` setter and `removeChild()` method will try to traverse the DOM (via
+  // `nextSibling` and `parentNode` respectively), which leads to infinite loops when testing
+  // `HtmlSanitizer` with cloberred elements on browsers that do not support the `<template>`
+  // element:
   // https://github.com/angular/angular/blob/213baa37b0b71e72d00ad7b606ebfc2ade06b934/packages/platform-browser/src/security/html_sanitizer.ts#L29-L38
-  // To avoid that, we "unpatch" `(HTML)Element#innerHTML` and apply the patch only for the relevant
+  // To avoid that, we "unpatch" these properties/methods and apply the patch only for the relevant
   // `@angular/elements` tests.
-  var patchTarget;
+  var patchConfig = {'innerHTML': ['Element', 'HTMLElement'], 'removeChild': ['Node']};
-  var originalDescriptor;
+  var patchTargets = {};
+  var originalDescriptors = {};
   if (!window.customElements) {
-    ['Element', 'HTMLElement']
+    Object.keys(patchConfig).forEach(function(prop) {
+      patchConfig[prop]
           .map(function(name) { return window[name].prototype; })
           .some(function(candidatePatchTarget) {
             var candidateOriginalDescriptor =
-              Object.getOwnPropertyDescriptor(candidatePatchTarget, 'innerHTML');
+                Object.getOwnPropertyDescriptor(candidatePatchTarget, prop);
 
             if (candidateOriginalDescriptor) {
-            patchTarget = candidatePatchTarget;
+              patchTargets[prop] = candidatePatchTarget;
-            originalDescriptor = candidateOriginalDescriptor;
+              originalDescriptors[prop] = candidateOriginalDescriptor;
               return true;
             }
           });
+    });
   }
 
   var polyfillPath = !window.customElements ?
@@ -188,24 +194,32 @@ function loadCustomElementsPolyfills() {
         // but custom element polyfills will replace `HTMLElement` with an anonymous function.
         Object.defineProperty(HTMLElement, 'name', {value: 'HTMLElement'});
 
-        // Create helper functions on `window` for patching/restoring `(HTML)Element#innerHTML`.
+        // Create helper functions on `window` for patching/restoring properties/methods.
-        if (!patchTarget) {
+        Object.keys(patchConfig).forEach(function(prop) {
-          window.$$patchInnerHtmlProp = window.$$restoreInnerHtmlProp = function() {};
+          var patchMethod = '$$patch_' + prop;
+          var restoreMethod = '$$restore_' + prop;
+
+          if (!patchTargets[prop]) {
+            // No patching detected. Create no-op functions.
+            window[patchMethod] = window[restoreMethod] = function() {};
           } else {
-          var patchedDescriptor = Object.getOwnPropertyDescriptor(patchTarget, 'innerHTML');
+            var patchTarget = patchTargets[prop];
+            var originalDescriptor = originalDescriptors[prop];
+            var patchedDescriptor = Object.getOwnPropertyDescriptor(patchTarget, prop);
 
-          window.$$patchInnerHtmlProp = function() {
+            window[patchMethod] = function() {
-            Object.defineProperty(patchTarget, 'innerHTML', patchedDescriptor);
+              Object.defineProperty(patchTarget, prop, patchedDescriptor);
             };
-          window.$$restoreInnerHtmlProp = function() {
+            window[restoreMethod] = function() {
-            Object.defineProperty(patchTarget, 'innerHTML', originalDescriptor);
+              Object.defineProperty(patchTarget, prop, originalDescriptor);
             };
 
-          // Restore `innerHTML`. The patch will be manually applied only during the
+            // Restore `prop`. The patch will be manually applied only during the
             // `@angular/elements` tests that need it.
-          window.$$restoreInnerHtmlProp();
+            window[restoreMethod]();
           }
         });
+      });
 
   return loadedPromise;
 }

tools/public_api_guard/elements/elements.d.ts

@@ -16,14 +16,13 @@ export interface NgElementConfig {
         [key: string]: string;
     };
     injector: Injector;
-    propertyInputs?: string[];
     strategyFactory?: NgElementStrategyFactory;
 }
 
 /** @experimental */
 export interface NgElementConstructor<P> {
     readonly observedAttributes: string[];
-    new (): NgElement & WithProperties<P>;
+    new (injector: Injector): NgElement & WithProperties<P>;
 }
 
 /** @experimental */
@@ -43,7 +42,7 @@ export interface NgElementStrategyEvent {
 
 /** @experimental */
 export interface NgElementStrategyFactory {
-    create(): NgElementStrategy;
+    create(injector: Injector): NgElementStrategy;
 }
 
 /** @experimental */