fix(forms): Update NgModel's viewModel when model changes

Closes angular#3627

Author: mgreenland

modules/angular2/src/core/forms/directives/ng_model.ts

@@ -57,6 +57,7 @@ export class NgModel extends NgControl implements OnChanges {
 
  if (isPropertyUpdated(c, this.viewModel)) {
  this._control.updateValue(this.model);
+ this.viewModel = this.model;
  }
  }
 

modules/angular2/test/core/forms/integration_spec.ts

@@ -756,6 +756,39 @@ export function main() {
  // selection start has not changed because we did not reset the value
  expect(input.selectionStart).toEqual(1);
  })));
+
+ it("should update the view when the model is set back to what used to be in the view",
+ inject([TestComponentBuilder], fakeAsync((tcb: TestComponentBuilder) => {
+ var t = `<input type="text" [(ng-model)]="name">`;
+ var rootTC;
+ tcb.overrideTemplate(MyComp, t).createAsync(MyComp).then(
+ (root) => { rootTC = root; });
+ tick();
+ rootTC.componentInstance.name = "";
+ rootTC.detectChanges();
+
+ // Type "aa" into the input.
+ var input = rootTC.query(By.css("input")).nativeElement;
+ input.value = "aa";
+ input.selectionStart = 1;
+ dispatchEvent(input, "change");
+
+ tick();
+ rootTC.detectChanges();
+ expect(rootTC.componentInstance.name).toEqual("aa");
+
+ // Programatically update the input value to be "bb".
+ rootTC.componentInstance.name = "bb";
+ tick();
+ rootTC.detectChanges();
+ expect(input.value).toEqual("bb");
+
+ // Programatically set it back to "aa".
+ rootTC.componentInstance.name = "aa";
+ tick();
+ rootTC.detectChanges();
+ expect(input.value).toEqual("aa");
+ })));
  });
  });
 }