fix(linker): prevent pollution of empty embeddedView context (#10548)

Fixes #10045

modules/@angular/compiler/src/template_parser/template_parser.ts

@@ -15,12 +15,12 @@ import {Parser} from '../expression_parser/parser';
 import {ListWrapper, SetWrapper, StringMapWrapper} from '../facade/collection';
 import {BaseException} from '../facade/exceptions';
 import {isBlank, isPresent} from '../facade/lang';
+import {Identifiers, identifierToken} from '../identifiers';
 import * as html from '../ml_parser/ast';
 import {HtmlParser, ParseTreeResult} from '../ml_parser/html_parser';
 import {expandNodes} from '../ml_parser/icu_ast_expander';
 import {InterpolationConfig} from '../ml_parser/interpolation_config';
 import {mergeNsAndName, splitNsName} from '../ml_parser/tags';
-import {Identifiers, identifierToken} from '../identifiers';
 import {ParseError, ParseErrorLevel, ParseSourceSpan} from '../parse_util';
 import {ProviderElementContext, ProviderViewContext} from '../provider_analyzer';
 import {ElementSchemaRegistry} from '../schema/element_schema_registry';
@@ -32,6 +32,7 @@ import {AttrAst, BoundDirectivePropertyAst, BoundElementPropertyAst, BoundEventA
 import {PreparsedElementType, preparseElement} from './template_preparser';
 
 
+
 // Group 1 = "bind-"
 // Group 2 = "var-"
 // Group 3 = "let-"

modules/@angular/core/src/linker/template_ref.ts

@@ -6,14 +6,11 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {isBlank} from '../facade/lang';
 import {AppElement} from './element';
 import {ElementRef} from './element_ref';
 import {AppView} from './view';
 import {EmbeddedViewRef} from './view_ref';
 
-const EMPTY_CONTEXT = new Object();
-
 /**
  * Represents an Embedded Template that can be used to instantiate Embedded Views.
  *
@@ -51,10 +48,7 @@ export class TemplateRef_<C> extends TemplateRef<C> {
   createEmbeddedView(context: C): EmbeddedViewRef<C> {
     var view: AppView<C> = this._viewFactory(
         this._appElement.parentView.viewUtils, this._appElement.parentInjector, this._appElement);
-    if (isBlank(context)) {
-      context = <any>EMPTY_CONTEXT;
-    }
-    view.create(context, null, null);
+    view.create(context || <any>{}, null, null);
     return view.ref;
   }
 

modules/@angular/core/test/linker/integration_spec.ts

@@ -470,6 +470,27 @@ function declareTests({useJit}: {useJit: boolean}) {
                    });
              }));
 
+      it('should not share empty context for template directives - issue #10045',
+         inject(
+             [TestComponentBuilder, AsyncTestCompleter],
+             (tcb: TestComponentBuilder, async: AsyncTestCompleter) => {
+               tcb.overrideView(
+                      MyComp, new ViewMetadata({
+                        template:
+                            '<template pollutedContext let-foo="bar">{{foo}}</template><template noContext let-foo="bar">{{foo}}</template>',
+                        directives: [PollutedContext, NoContext]
+                      }))
+
+                   .createAsync(MyComp)
+                   .then((fixture) => {
+
+                     fixture.detectChanges();
+                     expect(fixture.debugElement.nativeElement).toHaveText('baz');
+
+                     async.done();
+                   });
+             }));
+
       it('should not detach views in ViewContainers when the parent view is destroyed.',
          inject(
              [TestComponentBuilder, AsyncTestCompleter],
@@ -2303,6 +2324,21 @@ class SomeViewport {
   }
 }
 
+@Directive({selector: '[pollutedContext]'})
+class PollutedContext {
+  constructor(private tplRef: TemplateRef<any>, private vcRef: ViewContainerRef) {
+    const evRef = this.vcRef.createEmbeddedView(this.tplRef);
+    evRef.context.bar = 'baz';
+  }
+}
+
+@Directive({selector: '[noContext]'})
+class NoContext {
+  constructor(private tplRef: TemplateRef<any>, private vcRef: ViewContainerRef) {
+    this.vcRef.createEmbeddedView(this.tplRef);
+  }
+}
+
 @Pipe({name: 'double'})
 class DoublePipe implements PipeTransform, OnDestroy {
   ngOnDestroy() {}