feat(forms): add support for Validator

Currently, the only way for a directive to export a validator is by providing a function. This makes it ackward to write validators that depend on directive inputs. In addition to supporting functions as validators, classes implementing the Validator interface are supported too.

modules/angular2/src/core/forms.ts

@@ -37,7 +37,8 @@ export {NG_VALIDATORS, Validators} from './forms/validators';
 export {
   RequiredValidator,
   MinLengthValidator,
-  MaxLengthValidator
+  MaxLengthValidator,
+  Validator
 } from './forms/directives/validators';
 export {FormBuilder} from './forms/form_builder';
 

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

@@ -1,5 +1,6 @@
 import {ControlValueAccessor} from './control_value_accessor';
 import {AbstractControlDirective} from './abstract_control_directive';
+import {unimplemented} from 'angular2/src/core/facade/exceptions';
 
 /**
  * A base class that all control directive extend.
@@ -13,7 +14,7 @@ export class NgControl extends AbstractControlDirective {
   name: string = null;
   valueAccessor: ControlValueAccessor = null;
 
-  get validator(): Function { return null; }
+  get validator(): Function { return unimplemented(); }
 
-  viewToModelUpdate(newValue: any): void {}
+  viewToModelUpdate(newValue: any): void { return unimplemented(); }
 }

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

@@ -8,7 +8,7 @@ import {forwardRef, Host, SkipSelf, Provider, Inject, Optional} from 'angular2/s
 import {ControlContainer} from './control_container';
 import {NgControl} from './ng_control';
 import {ControlValueAccessor, NG_VALUE_ACCESSOR} from './control_value_accessor';
-import {controlPath, isPropertyUpdated, selectValueAccessor} from './shared';
+import {controlPath, composeValidators, isPropertyUpdated, selectValueAccessor} from './shared';
 import {Control} from '../model';
 import {Validators, NG_VALIDATORS} from '../validators';
 
@@ -85,16 +85,17 @@ export class NgControlName extends NgControl implements OnChanges,
   update = new EventEmitter();
   model: any;
   viewModel: any;
-  validators: Function[];
+  private _validator: Function;
   /** @internal */
   _added = false;
 
   constructor(@Host() @SkipSelf() parent: ControlContainer,
-              @Optional() @Inject(NG_VALIDATORS) validators: Function[],
+              @Optional() @Inject(NG_VALIDATORS) validators:
+                  /* Array<Validator|Function> */ any[],
               @Optional() @Inject(NG_VALUE_ACCESSOR) valueAccessors: ControlValueAccessor[]) {
     super();
     this._parent = parent;
-    this.validators = validators;
+    this._validator = composeValidators(validators);
     this.valueAccessor = selectValueAccessor(this, valueAccessors);
   }
 
@@ -120,7 +121,7 @@ export class NgControlName extends NgControl implements OnChanges,
 
   get formDirective(): any { return this._parent.formDirective; }
 
-  get control(): Control { return this.formDirective.getControl(this); }
+  get validator(): Function { return this._validator; }
 
-  get validator(): Function { return Validators.compose(this.validators); }
+  get control(): Control { return this.formDirective.getControl(this); }
 }

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

@@ -9,7 +9,7 @@ import {NgControl} from './ng_control';
 import {Control} from '../model';
 import {Validators, NG_VALIDATORS} from '../validators';
 import {ControlValueAccessor, NG_VALUE_ACCESSOR} from './control_value_accessor';
-import {setUpControl, isPropertyUpdated, selectValueAccessor} from './shared';
+import {setUpControl, composeValidators, isPropertyUpdated, selectValueAccessor} from './shared';
 
 const formControlBinding =
     CONST_EXPR(new Provider(NgControl, {useExisting: forwardRef(() => NgFormControl)}));
@@ -73,12 +73,13 @@ export class NgFormControl extends NgControl implements OnChanges {
   update = new EventEmitter();
   model: any;
   viewModel: any;
-  validators: Function[];
+  private _validator: Function;
 
-  constructor(@Optional() @Inject(NG_VALIDATORS) validators: Function[],
+  constructor(@Optional() @Inject(NG_VALIDATORS) validators:
+                  /* Array<Validator|Function> */ any[],
               @Optional() @Inject(NG_VALUE_ACCESSOR) valueAccessors: ControlValueAccessor[]) {
     super();
-    this.validators = validators;
+    this._validator = composeValidators(validators);
     this.valueAccessor = selectValueAccessor(this, valueAccessors);
   }
 
@@ -95,9 +96,9 @@ export class NgFormControl extends NgControl implements OnChanges {
 
   get path(): string[] { return []; }
 
-  get control(): Control { return this.form; }
+  get validator(): Function { return this._validator; }
 
-  get validator(): Function { return Validators.compose(this.validators); }
+  get control(): Control { return this.form; }
 
   viewToModelUpdate(newValue: any): void {
     this.viewModel = newValue;

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

@@ -8,7 +8,7 @@ import {ControlValueAccessor, NG_VALUE_ACCESSOR} from './control_value_accessor'
 import {NgControl} from './ng_control';
 import {Control} from '../model';
 import {Validators, NG_VALIDATORS} from '../validators';
-import {setUpControl, isPropertyUpdated, selectValueAccessor} from './shared';
+import {setUpControl, isPropertyUpdated, selectValueAccessor, composeValidators} from './shared';
 
 const formControlBinding =
     CONST_EXPR(new Provider(NgControl, {useExisting: forwardRef(() => NgModel)}));
@@ -49,12 +49,13 @@ export class NgModel extends NgControl implements OnChanges {
   update = new EventEmitter();
   model: any;
   viewModel: any;
-  validators: Function[];
+  private _validator: Function;
 
-  constructor(@Optional() @Inject(NG_VALIDATORS) validators: Function[],
+  constructor(@Optional() @Inject(NG_VALIDATORS) validators:
+                  /* Array<Validator|Function> */ any[],
               @Optional() @Inject(NG_VALUE_ACCESSOR) valueAccessors: ControlValueAccessor[]) {
     super();
-    this.validators = validators;
+    this._validator = composeValidators(validators);
     this.valueAccessor = selectValueAccessor(this, valueAccessors);
   }
 
@@ -75,7 +76,7 @@ export class NgModel extends NgControl implements OnChanges {
 
   get path(): string[] { return []; }
 
-  get validator(): Function { return Validators.compose(this.validators); }
+  get validator(): Function { return this._validator; }
 
   viewToModelUpdate(newValue: any): void {
     this.viewModel = newValue;

modules/angular2/src/core/forms/directives/normalize_validator.dart

@@ -0,0 +1,12 @@
+library angular2.core.forms.normalize_validators;
+
+import 'package:angular2/src/core/forms/directives/validators.dart' show Validator;
+
+Function normalizeValidator(dynamic validator){
+  if (validator is Validator) {
+    return (c) => validator.validate(c);
+  } else {
+    return validator;
+  }
+}
+

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

@@ -0,0 +1,9 @@
+import {Validator} from './validators';
+
+export function normalizeValidator(validator: Function | Validator): Function {
+  if ((<Validator>validator).validate !== undefined) {
+    return (c) => (<Validator>validator).validate(c);
+  } else {
+    return <Function>validator;
+  }
+}

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

@@ -15,6 +15,7 @@ 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';
+import {normalizeValidator} from './normalize_validator';
 
 
 export function controlPath(name: string, parent: ControlContainer): string[] {
@@ -59,6 +60,12 @@ export function setProperty(renderer: Renderer, elementRef: ElementRef, propName
   renderer.setElementProperty(elementRef, propName, propValue);
 }
 
+export function composeValidators(
+    validators: /* Array<Validator|Function> */ any[]): Function {
+  return isPresent(validators) ? Validators.compose(validators.map(normalizeValidator)) :
+                                 Validators.nullValidator;
+}
+
 export function isPropertyUpdated(changes: {[key: string]: any}, viewModel: any): boolean {
   if (!StringMapWrapper.contains(changes, "model")) return false;
   var change = changes["model"];

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

@@ -2,8 +2,30 @@ import {forwardRef, Provider, OpaqueToken} from 'angular2/src/core/di';
 import {CONST_EXPR} from 'angular2/src/core/facade/lang';
 import {Attribute, Directive} from 'angular2/src/core/metadata';
 import {Validators, NG_VALIDATORS} from '../validators';
+import {Control} from '../model';
+import * as modelModule from '../model';
 import {NumberWrapper} from "angular2/src/core/facade/lang";
 
+
+/**
+ * An interface that can be implemented by classes that can act as validators.
+ *
+ * ## Usage
+ *
+ * ```typescript
+ * @Directive({
+ *   selector: '[custom-validator]',
+ *   providers: [provide(NG_VALIDATORS, {useExisting: CustomValidatorDirective, multi: true})]
+ * })
+ * class CustomValidatorDirective implements Validator {
+ *   validate(c: Control): {[key: string]: any} {
+ *     return {"custom": true};
+ *   }
+ * }
+ * ```
+ */
+export interface Validator { validate(c: modelModule.Control): {[key: string]: any}; }
+
 const REQUIRED_VALIDATOR =
     CONST_EXPR(new Provider(NG_VALIDATORS, {useValue: Validators.required, multi: true}));
 
@@ -14,40 +36,34 @@ const REQUIRED_VALIDATOR =
 export class RequiredValidator {
 }
 
-function createMinLengthValidator(dir): any {
-  return Validators.minLength(dir.minLength);
-}
-const MIN_LENGTH_VALIDATOR = CONST_EXPR(new Provider(NG_VALIDATORS, {
-  useFactory: createMinLengthValidator,
-  deps: [forwardRef(() => MinLengthValidator)],
-  multi: true
-}));
+const MIN_LENGTH_VALIDATOR = CONST_EXPR(
+    new Provider(NG_VALIDATORS, {useExisting: forwardRef(() => MinLengthValidator), multi: true}));
 @Directive({
   selector: '[minlength][ng-control],[minlength][ng-form-control],[minlength][ng-model]',
   providers: [MIN_LENGTH_VALIDATOR]
 })
-export class MinLengthValidator {
-  minLength: number;
+export class MinLengthValidator implements Validator {
+  private _validator: Function;
+
   constructor(@Attribute("minlength") minLength: string) {
-    this.minLength = NumberWrapper.parseInt(minLength, 10);
+    this._validator = Validators.minLength(NumberWrapper.parseInt(minLength, 10));
   }
+
+  validate(c: Control): {[key: string]: any} { return this._validator(c); }
 }
 
-function createMaxLengthValidator(dir): any {
-  return Validators.maxLength(dir.maxLength);
-}
-const MAX_LENGTH_VALIDATOR = CONST_EXPR(new Provider(NG_VALIDATORS, {
-  useFactory: createMaxLengthValidator,
-  deps: [forwardRef(() => MaxLengthValidator)],
-  multi: true
-}));
+const MAX_LENGTH_VALIDATOR = CONST_EXPR(
+    new Provider(NG_VALIDATORS, {useExisting: forwardRef(() => MaxLengthValidator), multi: true}));
 @Directive({
   selector: '[maxlength][ng-control],[maxlength][ng-form-control],[maxlength][ng-model]',
   providers: [MAX_LENGTH_VALIDATOR]
 })
-export class MaxLengthValidator {
-  maxLength: number;
-  constructor(@Attribute("maxlength") maxLength: string) {
-    this.maxLength = NumberWrapper.parseInt(maxLength, 10);
+export class MaxLengthValidator implements Validator {
+  private _validator: Function;
+
+  constructor(@Attribute("maxlength") minLength: string) {
+    this._validator = Validators.maxLength(NumberWrapper.parseInt(minLength, 10));
   }
+
+  validate(c: Control): {[key: string]: any} { return this._validator(c); }
 }

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

@@ -32,11 +32,12 @@ import {
   DefaultValueAccessor,
   CheckboxControlValueAccessor,
   SelectControlValueAccessor,
-  QueryList
+  QueryList,
+  Validator
 } from 'angular2/core';
 
 
-import {selectValueAccessor} from 'angular2/src/core/forms/directives/shared';
+import {selectValueAccessor, composeValidators} from 'angular2/src/core/forms/directives/shared';
 
 import {SimpleChange} from 'angular2/src/core/change_detection';
 
@@ -49,6 +50,10 @@ class DummyControlValueAccessor implements ControlValueAccessor {
   writeValue(obj: any): void { this.writtenValue = obj; }
 }
 
+class CustomValidatorDirective implements Validator {
+  validate(c: Control): {[key: string]: any} { return {"custom": true}; }
+}
+
 export function main() {
   describe("Form Directives", () => {
     var defaultAccessor;
@@ -97,6 +102,21 @@ export function main() {
           expect(() => selectValueAccessor(dir, [customAccessor, customAccessor])).toThrowError();
         });
       });
+
+      describe("composeValidators", () => {
+        it("should compose functions", () => {
+          var dummy1 = (_) => ({"dummy1": true});
+          var dummy2 = (_) => ({"dummy2": true});
+          var v = composeValidators([dummy1, dummy2]);
+          expect(v(new Control(""))).toEqual({"dummy1": true, "dummy2": true});
+        });
+
+        it("should compose validator directives", () => {
+          var dummy1 = (_) => ({"dummy1": true});
+          var v = composeValidators([dummy1, new CustomValidatorDirective()]);
+          expect(v(new Control(""))).toEqual({"dummy1": true, "custom": true});
+        });
+      });
     });
 
     describe("NgFormModel", () => {
@@ -113,7 +133,7 @@ export function main() {
         });
         form.form = formModel;
 
-        loginControlDir = new NgControlName(form, [], [defaultAccessor]);
+        loginControlDir = new NgControlName(form, [Validators.required], [defaultAccessor]);
         loginControlDir.name = "login";
         loginControlDir.valueAccessor = new DummyControlValueAccessor();
       });
@@ -147,8 +167,6 @@ export function main() {
         });
 
         it("should set up validator", () => {
-          loginControlDir.validators = [Validators.required];
-
           expect(formModel.find(["login"]).valid).toBe(true);
 
           // this will add the required validator and recalculate the validity
@@ -335,7 +353,7 @@ export function main() {
       };
 
       beforeEach(() => {
-        controlDir = new NgFormControl([], [defaultAccessor]);
+        controlDir = new NgFormControl([Validators.required], [defaultAccessor]);
         controlDir.valueAccessor = new DummyControlValueAccessor();
 
         control = new Control(null);
@@ -353,8 +371,6 @@ export function main() {
       });
 
       it("should set up validator", () => {
-        controlDir.validators = [Validators.required];
-
         expect(control.valid).toBe(true);
 
         // this will add the required validator and recalculate the validity
@@ -368,7 +384,7 @@ export function main() {
       var ngModel;
 
       beforeEach(() => {
-        ngModel = new NgModel([], [defaultAccessor]);
+        ngModel = new NgModel([Validators.required], [defaultAccessor]);
         ngModel.valueAccessor = new DummyControlValueAccessor();
       });
 
@@ -385,8 +401,6 @@ export function main() {
       });
 
       it("should set up validator", () => {
-        ngModel.validators = [Validators.required];
-
         expect(ngModel.control.valid).toBe(true);
 
         // this will add the required validator and recalculate the validity

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

@@ -31,10 +31,13 @@ import {
   NgFor,
   NgForm,
   Validators,
+  forwardRef,
+  Validator
 } from 'angular2/core';
 import {By} from 'angular2/src/core/debug';
 import {ListWrapper} from 'angular2/src/core/facade/collection';
 import {ObservableWrapper} from 'angular2/src/core/facade/async';
+import {CONST_EXPR} from 'angular2/src/core/facade/lang';
 
 export function main() {
   describe("integration tests", () => {

modules/angular2/test/public_api_spec.ts

@@ -414,11 +414,10 @@ var NG_API = [
   'DecimalPipe.transform()',
   'RequiredValidator',
   'MinLengthValidator',
-  'MinLengthValidator.minLength',
-  'MinLengthValidator.minLength=',
+  'MinLengthValidator.validate()',
   'MaxLengthValidator',
-  'MaxLengthValidator.maxLength',
-  'MaxLengthValidator.maxLength=',
+  'MaxLengthValidator.validate()',
+  'Validator:dart',
   'DefaultValueAccessor',
   'DefaultValueAccessor.onChange',
   'DefaultValueAccessor.onChange=',
@@ -686,8 +685,6 @@ var NG_API = [
   'NgControlName.update=',
   'NgControlName.valid',
   'NgControlName.validator',
-  'NgControlName.validators',
-  'NgControlName.validators=',
   'NgControlName.value',
   'NgControlName.valueAccessor',
   'NgControlName.valueAccessor=',
@@ -745,8 +742,6 @@ var NG_API = [
   'NgFormControl.update=',
   'NgFormControl.valid',
   'NgFormControl.validator',
-  'NgFormControl.validators',
-  'NgFormControl.validators=',
   'NgFormControl.value',
   'NgFormControl.valueAccessor',
   'NgFormControl.valueAccessor=',
@@ -802,8 +797,6 @@ var NG_API = [
   'NgModel.update=',
   'NgModel.valid',
   'NgModel.validator',
-  'NgModel.validators',
-  'NgModel.validators=',
   'NgModel.value',
   'NgModel.valueAccessor',
   'NgModel.valueAccessor=',