feat(forms): add input[type=number] value accessor

Closes #4014

Closes #4761

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

@@ -7,6 +7,7 @@ import {NgFormModel} from './directives/ng_form_model';
 import {NgForm} from './directives/ng_form';
 import {DefaultValueAccessor} from './directives/default_value_accessor';
 import {CheckboxControlValueAccessor} from './directives/checkbox_value_accessor';
+import {NumberValueAccessor} from './directives/number_value_accessor';
 import {NgControlStatus} from './directives/ng_control_status';
 import {
   SelectControlValueAccessor,
@@ -58,6 +59,7 @@ export const FORM_DIRECTIVES: Type[] = CONST_EXPR([
 
   NgSelectOption,
   DefaultValueAccessor,
+  NumberValueAccessor,
   CheckboxControlValueAccessor,
   SelectControlValueAccessor,
   NgControlStatus,

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

@@ -0,0 +1,43 @@
+import {Directive} from 'angular2/src/core/metadata';
+import {ElementRef} from 'angular2/src/core/linker';
+import {Renderer} from 'angular2/src/core/render';
+import {Self, forwardRef, Provider} from 'angular2/src/core/di';
+import {NG_VALUE_ACCESSOR, ControlValueAccessor} from './control_value_accessor';
+import {isBlank, CONST_EXPR, NumberWrapper} from 'angular2/src/core/facade/lang';
+import {setProperty} from './shared';
+
+const NUMBER_VALUE_ACCESSOR = CONST_EXPR(new Provider(
+    NG_VALUE_ACCESSOR, {useExisting: forwardRef(() => NumberValueAccessor), multi: true}));
+
+/**
+ * The accessor for writing a number value and listening to changes that is used by the
+ * {@link NgModel}, {@link NgFormControl}, and {@link NgControlName} directives.
+ *
+ *  # Example
+ *  ```
+ *  <input type="number" [(ng-model)]="age">
+ *  ```
+ */
+@Directive({
+  selector:
+      'input[type=number][ng-control],input[type=number][ng-form-control],input[type=number][ng-model]',
+  host: {
+    '(change)': 'onChange($event.target.value)',
+    '(input)': 'onChange($event.target.value)',
+    '(blur)': 'onTouched()'
+  },
+  bindings: [NUMBER_VALUE_ACCESSOR]
+})
+export class NumberValueAccessor implements ControlValueAccessor {
+  onChange = (_) => {};
+  onTouched = () => {};
+
+  constructor(private _renderer: Renderer, private _elementRef: ElementRef) {}
+
+  writeValue(value: number): void { setProperty(this._renderer, this._elementRef, 'value', value); }
+
+  registerOnChange(fn: (_: number) => void): void {
+    this.onChange = (value) => { fn(NumberWrapper.parseFloat(value)); };
+  }
+  registerOnTouched(fn: () => void): void { this.onTouched = fn; }
+}

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

@@ -10,6 +10,7 @@ import {ControlValueAccessor} from './control_value_accessor';
 import {ElementRef, QueryList} from 'angular2/src/core/linker';
 import {Renderer} from 'angular2/src/core/render';
 import {DefaultValueAccessor} from './default_value_accessor';
+import {NumberValueAccessor} from './number_value_accessor';
 import {CheckboxControlValueAccessor} from './checkbox_value_accessor';
 import {SelectControlValueAccessor} from './select_control_value_accessor';
 
@@ -72,7 +73,7 @@ export function selectValueAccessor(dir: NgControl, valueAccessors: ControlValue
     if (v instanceof DefaultValueAccessor) {
       defaultAccessor = v;
 
-    } else if (v instanceof CheckboxControlValueAccessor ||
+    } else if (v instanceof CheckboxControlValueAccessor || v instanceof NumberValueAccessor ||
                v instanceof SelectControlValueAccessor) {
       if (isPresent(builtinAccessor))
         _throwError(dir, "More than one built-in value accessor matches");

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

@@ -274,6 +274,28 @@ export function main() {
            });
          }));
 
+      it("should support <type=number>",
+         inject([TestComponentBuilder, AsyncTestCompleter], (tcb: TestComponentBuilder, async) => {
+           var t = `<div [ng-form-model]="form">
+                  <input type="number" ng-control="num">
+                </div>`;
+
+           tcb.overrideTemplate(MyComp, t).createAsync(MyComp).then((rootTC) => {
+             rootTC.debugElement.componentInstance.form =
+                 new ControlGroup({"num": new Control(10)});
+             rootTC.detectChanges();
+
+             var input = rootTC.debugElement.query(By.css("input"));
+             expect(input.nativeElement.value).toEqual("10");
+
+             input.nativeElement.value = "20";
+             dispatchEvent(input.nativeElement, "change");
+
+             expect(rootTC.debugElement.componentInstance.form.value).toEqual({"num": 20});
+             async.done();
+           });
+         }));
+
       it("should support <select>",
          inject([TestComponentBuilder, AsyncTestCompleter], (tcb: TestComponentBuilder, async) => {
            var t = `<div [ng-form-model]="form">