feat(radio): add required attribute to radio-group (#5751)

* feat(radio): add required attribute to radio-group

* chore(radio): add sample using required attribute in demo-app

* feat(radio): add required attribute to radio-button

* refactor(radio): change let to const when possible

* style(radio): remove trailing white-spaces

* docs: revert radio.md

src/demo-app/radio/radio-demo.html

@@ -21,10 +21,20 @@
       Disable buttons
     </button>
   </div>
+  <div>
+    <span>isRequired: {{isRequired}}</span>
+    <button md-raised-button (click)="isRequired=!isRequired" class="demo-button">
+      Require buttons
+    </button>
+  </div>
   <div>
     <span><md-checkbox [(ngModel)]="isAlignEnd">Align end</md-checkbox></span>
   </div>
-  <md-radio-group name="my_options" [disabled]="isDisabled" [align]="isAlignEnd ? 'end' : 'start'">
+  <md-radio-group
+    name="my_options"
+    [disabled]="isDisabled"
+    [required]="isRequired"
+    [align]="isAlignEnd ? 'end' : 'start'">
     <md-radio-button value="option_1">Option 1</md-radio-button>
     <md-radio-button value="option_2">Option 2</md-radio-button>
     <md-radio-button value="option_3">Option 3</md-radio-button>

src/demo-app/radio/radio-demo.ts

@@ -8,8 +8,9 @@ import {Component} from '@angular/core';
   styleUrls: ['radio-demo.css'],
 })
 export class RadioDemo {
-  isDisabled: boolean = false;
   isAlignEnd: boolean = false;
+  isDisabled: boolean = false;
+  isRequired: boolean = false;
   favoriteSeason: string = 'Autumn';
   seasonOptions = [
     'Winter',

src/lib/radio/radio.html

@@ -16,6 +16,7 @@
          [checked]="checked"
          [disabled]="disabled"
          [name]="name"
+         [required]="required"
          [attr.aria-label]="ariaLabel"
          [attr.aria-labelledby]="ariaLabelledby"
          (change)="_onInputChange($event)"

src/lib/radio/radio.spec.ts

@@ -62,7 +62,7 @@ describe('MdRadio', () => {
 
     it('should set individual radio names based on the group name', () => {
       expect(groupInstance.name).toBeTruthy();
-      for (let radio of radioInstances) {
+      for (const radio of radioInstances) {
         expect(radio.name).toBe(groupInstance.name);
       }
     });
@@ -92,14 +92,14 @@ describe('MdRadio', () => {
       testComponent.labelPos = 'before';
       fixture.detectChanges();
 
-      for (let radio of radioInstances) {
+      for (const radio of radioInstances) {
         expect(radio.labelPosition).toBe('before');
       }
 
       testComponent.labelPos = 'after';
       fixture.detectChanges();
 
-      for (let radio of radioInstances) {
+      for (const radio of radioInstances) {
         expect(radio.labelPosition).toBe('after');
       }
     });
@@ -108,11 +108,20 @@ describe('MdRadio', () => {
       testComponent.isGroupDisabled = true;
       fixture.detectChanges();
 
-      for (let radio of radioInstances) {
+      for (const radio of radioInstances) {
         expect(radio.disabled).toBe(true);
       }
     });
 
+    it('should set required to each radio button when the group is required', () => {
+      testComponent.isGroupRequired = true;
+      fixture.detectChanges();
+
+      for (const radio of radioInstances) {
+        expect(radio.required).toBe(true);
+      }
+    });
+
     it('should update the group value when one of the radios changes', () => {
       expect(groupInstance.value).toBeFalsy();
 
@@ -155,7 +164,7 @@ describe('MdRadio', () => {
     it('should emit a change event from radio buttons', () => {
       expect(radioInstances[0].checked).toBe(false);
 
-      let spies = radioInstances
+      const spies = radioInstances
         .map((radio, index) => jasmine.createSpy(`onChangeSpy ${index} for ${radio.name}`));
 
       spies.forEach((spy, index) => radioInstances[index].change.subscribe(spy));
@@ -178,7 +187,7 @@ describe('MdRadio', () => {
         programmatically`, () => {
       expect(groupInstance.value).toBeFalsy();
 
-      let changeSpy = jasmine.createSpy('radio-group change listener');
+      const changeSpy = jasmine.createSpy('radio-group change listener');
       groupInstance.change.subscribe(changeSpy);
 
       radioLabelElements[0].click();
@@ -265,7 +274,7 @@ describe('MdRadio', () => {
       testComponent.disableRipple = true;
       fixture.detectChanges();
 
-      for (let radioLabel of radioLabelElements) {
+      for (const radioLabel of radioLabelElements) {
         dispatchFakeEvent(radioLabel, 'mousedown');
         dispatchFakeEvent(radioLabel, 'mouseup');
 
@@ -275,7 +284,7 @@ describe('MdRadio', () => {
       testComponent.disableRipple = false;
       fixture.detectChanges();
 
-      for (let radioLabel of radioLabelElements) {
+      for (const radioLabel of radioLabelElements) {
         dispatchFakeEvent(radioLabel, 'mousedown');
         dispatchFakeEvent(radioLabel, 'mouseup');
 
@@ -285,7 +294,7 @@ describe('MdRadio', () => {
 
     it(`should update the group's selected radio to null when unchecking that radio
         programmatically`, () => {
-      let changeSpy = jasmine.createSpy('radio-group change listener');
+      const changeSpy = jasmine.createSpy('radio-group change listener');
       groupInstance.change.subscribe(changeSpy);
       radioInstances[0].checked = true;
 
@@ -305,7 +314,7 @@ describe('MdRadio', () => {
     });
 
     it('should not fire a change event from the group when a radio checked state changes', () => {
-      let changeSpy = jasmine.createSpy('radio-group change listener');
+      const changeSpy = jasmine.createSpy('radio-group change listener');
       groupInstance.change.subscribe(changeSpy);
       radioInstances[0].checked = true;
 
@@ -324,7 +333,7 @@ describe('MdRadio', () => {
     });
 
     it(`should update checked status if changed value to radio group's value`, () => {
-      let changeSpy = jasmine.createSpy('radio-group change listener');
+      const changeSpy = jasmine.createSpy('radio-group change listener');
       groupInstance.change.subscribe(changeSpy);
       groupInstance.value = 'apple';
 
@@ -403,25 +412,25 @@ describe('MdRadio', () => {
 
     it('should set individual radio names based on the group name', () => {
       expect(groupInstance.name).toBeTruthy();
-      for (let radio of radioInstances) {
+      for (const radio of radioInstances) {
         expect(radio.name).toBe(groupInstance.name);
       }
 
       groupInstance.name = 'new name';
 
-      for (let radio of radioInstances) {
+      for (const radio of radioInstances) {
         expect(radio.name).toBe(groupInstance.name);
       }
     });
 
     it('should check the corresponding radio button on group value change', () => {
       expect(groupInstance.value).toBeFalsy();
-      for (let radio of radioInstances) {
+      for (const radio of radioInstances) {
         expect(radio.checked).toBeFalsy();
       }
 
       groupInstance.value = 'vanilla';
-      for (let radio of radioInstances) {
+      for (const radio of radioInstances) {
         expect(radio.checked).toBe(groupInstance.value === radio.value);
       }
       expect(groupInstance.selected!.value).toBe(groupInstance.value);
@@ -539,12 +548,12 @@ describe('MdRadio', () => {
           .filter(debugEl => debugEl.componentInstance.name == 'fruit')
           .map(debugEl => debugEl.componentInstance);
 
-      let fruitRadioNativeElements = radioDebugElements
+      const fruitRadioNativeElements = radioDebugElements
           .filter(debugEl => debugEl.componentInstance.name == 'fruit')
           .map(debugEl => debugEl.nativeElement);
 
       fruitRadioNativeInputs = [];
-      for (let element of fruitRadioNativeElements) {
+      for (const element of fruitRadioNativeElements) {
         fruitRadioNativeInputs.push(<HTMLElement> element.querySelector('input'));
       }
     });
@@ -579,6 +588,14 @@ describe('MdRadio', () => {
       expect(weatherRadioInstances[2].checked).toBe(true);
     });
 
+    it('should add required attribute to the underlying input element if defined', () => {
+      const radioInstance = seasonRadioInstances[0];
+      radioInstance.required = true;
+      fixture.detectChanges();
+
+      expect(radioInstance.required).toBe(true);
+    });
+
     it('should add aria-label attribute to the underlying input element if defined', () => {
       expect(fruitRadioNativeInputs[0].getAttribute('aria-label')).toBe('Banana');
     });
@@ -630,6 +647,7 @@ describe('MdRadio', () => {
   template: `
   <md-radio-group [disabled]="isGroupDisabled"
                   [labelPosition]="labelPos"
+                  [required]="isGroupRequired"
                   [value]="groupValue"
                   name="test-name">
     <md-radio-button value="fire" [disableRipple]="disableRipple" [disabled]="isFirstDisabled"
@@ -647,8 +665,9 @@ describe('MdRadio', () => {
 })
 class RadiosInsideRadioGroup {
   labelPos: 'before' | 'after';
-  isGroupDisabled: boolean = false;
   isFirstDisabled: boolean = false;
+  isGroupDisabled: boolean = false;
+  isGroupRequired: boolean = false;
   groupValue: string | null = null;
   disableRipple: boolean = false;
   color: string | null;

src/lib/radio/radio.ts

@@ -105,6 +105,9 @@ export class MdRadioGroup extends _MdRadioGroupMixinBase
   /** Whether the radio group is disabled. */
   private _disabled: boolean = false;
 
+  /** Whether the radio group is required. */
+  private _required: boolean = false;
+
   /** The method to be called in order to update ngModel */
   _controlValueAccessorChangeFn: (value: any) => void = () => {};
 
@@ -189,12 +192,20 @@ export class MdRadioGroup extends _MdRadioGroupMixinBase
 
   /** Whether the radio group is disabled */
   @Input()
-  get disabled() { return this._disabled; }
+  get disabled(): boolean { return this._disabled; }
   set disabled(value) {
     this._disabled = coerceBooleanProperty(value);
     this._markRadiosForCheck();
   }
 
+  /** Whether the radio group is required */
+  @Input()
+  get required(): boolean { return this._required; }
+  set required(value: boolean) {
+    this._required = coerceBooleanProperty(value);
+    this._markRadiosForCheck();
+  }
+
   constructor(private _changeDetector: ChangeDetectorRef) {
     super();
   }
@@ -231,7 +242,7 @@ export class MdRadioGroup extends _MdRadioGroupMixinBase
   /** Updates the `selected` radio button from the internal _value state. */
   private _updateSelectedRadioFromValue(): void {
     // If the value already matches the selected radio, do nothing.
-    let isAlreadySelected = this._selected != null && this._selected.value == this._value;
+    const isAlreadySelected = this._selected != null && this._selected.value == this._value;
 
     if (this._radios != null && !isAlreadySelected) {
       this._selected = null;
@@ -247,7 +258,7 @@ export class MdRadioGroup extends _MdRadioGroupMixinBase
   /** Dispatch change event with current selection and group value. */
   _emitChangeEvent(): void {
     if (this._isInitialized) {
-      let event = new MdRadioChange();
+      const event = new MdRadioChange();
       event.source = this._selected;
       event.value = this._value;
       this.change.emit(event);
@@ -424,6 +435,15 @@ export class MdRadioButton extends _MdRadioButtonMixinBase
     this._disabled = coerceBooleanProperty(value);
   }
 
+  /** Whether the radio button is required. */
+  @Input()
+  get required(): boolean {
+    return this._required || (this.radioGroup && this.radioGroup.required);
+  }
+  set required(value: boolean) {
+    this._required = coerceBooleanProperty(value);
+  }
+
   /**
    * Event emitted when the checked state of this radio button changes.
    * Change events are only emitted when the value changes due to user interaction with
@@ -443,6 +463,9 @@ export class MdRadioButton extends _MdRadioButtonMixinBase
   /** Whether this radio is disabled. */
   private _disabled: boolean;
 
+  /** Whether this radio is required. */
+  private _required: boolean;
+
   /** Value assigned to this radio.*/
   private _value: any = null;
 
@@ -516,7 +539,7 @@ export class MdRadioButton extends _MdRadioButtonMixinBase
 
   /** Dispatch change event with current value. */
   private _emitChangeEvent(): void {
-    let event = new MdRadioChange();
+    const event = new MdRadioChange();
     event.source = this;
     event.value = this._value;
     this.change.emit(event);
@@ -547,7 +570,7 @@ export class MdRadioButton extends _MdRadioButtonMixinBase
     // emit its event object to the `change` output.
     event.stopPropagation();
 
-    let groupValueChanged = this.radioGroup && this.value != this.radioGroup.value;
+    const groupValueChanged = this.radioGroup && this.value != this.radioGroup.value;
     this.checked = true;
     this._emitChangeEvent();