fix (buttons) radio buttons no change on every click (#2132)

src/buttons/button-radio.directive.ts

@@ -1,5 +1,12 @@
 import {
-  Directive, ElementRef, HostBinding, forwardRef, HostListener, Input, OnInit, ChangeDetectorRef
+  Directive,
+  ElementRef,
+  HostBinding,
+  forwardRef,
+  HostListener,
+  Input,
+  OnInit,
+  ChangeDetectorRef
 } from '@angular/core';
 import { ControlValueAccessor, NG_VALUE_ACCESSOR } from '@angular/forms';
 
@@ -41,12 +48,17 @@ export class ButtonRadioDirective implements ControlValueAccessor, OnInit {
 
     if (this.uncheckable && this.btnRadio === this.value) {
       this.value = undefined;
-    } else {
-      this.value = this.btnRadio;
+      this.onTouched();
+      this.onChange(this.value);
+      return;
     }
 
-    this.onTouched();
-    this.onChange(this.value);
+    if (this.btnRadio !== this.value) {
+      this.value = this.btnRadio;
+      this.onTouched();
+      this.onChange(this.value);
+      return;
+    }
   }
 
   public constructor(el: ElementRef, private cdr: ChangeDetectorRef) {

src/spec/button.directive.spec.ts

@@ -491,6 +491,21 @@ describe('Directive: Buttons', () => {
       expect(btn.children[3].classList).not.toContain('active');
     }));
 
+    it('should not toggle when click in active button without uncheckable', () => {
+      fixture = createComponent(html, 'OnPush');
+      context = fixture.componentInstance;
+      element = fixture.nativeElement;
+
+      let btn = element.querySelector('.btn-group.radio');
+      expect(context.radioModel).toEqual('Middle');
+
+      (btn.children[1] as HTMLElement).click();
+      fixture.detectChanges();
+      expect(btn.children[0].classList).not.toContain('active');
+      expect(btn.children[1].classList).toContain('active');
+      expect(btn.children[2].classList).not.toContain('active');
+    });
+
     it('should unset active class via click', () => {
       fixture = createComponent(html);
       context = fixture.componentInstance;