feat(menu): allow disabling ripples on items (#8388)

Closes #8261

src/lib/menu/menu-item.html

@@ -1,3 +1,5 @@
 <ng-content></ng-content>
-<div class="mat-menu-ripple" *ngIf="!disabled" mat-ripple [matRippleTrigger]="_getHostElement()">
+<div class="mat-menu-ripple" matRipple
+     [matRippleDisabled]="disableRipple || disabled"
+     [matRippleTrigger]="_getHostElement()">
 </div>

src/lib/menu/menu-item.ts

@@ -14,13 +14,18 @@ import {
   OnDestroy,
   ViewEncapsulation,
 } from '@angular/core';
-import {CanDisable, mixinDisabled} from '@angular/material/core';
+import {
+  CanDisable,
+  CanDisableRipple,
+  mixinDisabled,
+  mixinDisableRipple
+} from '@angular/material/core';
 import {Subject} from 'rxjs/Subject';
 
 // Boilerplate for applying mixins to MatMenuItem.
 /** @docs-private */
 export class MatMenuItemBase {}
-export const _MatMenuItemMixinBase = mixinDisabled(MatMenuItemBase);
+export const _MatMenuItemMixinBase = mixinDisableRipple(mixinDisabled(MatMenuItemBase));
 
 /**
  * This directive is intended to be used inside an mat-menu tag.
@@ -30,7 +35,7 @@ export const _MatMenuItemMixinBase = mixinDisabled(MatMenuItemBase);
   moduleId: module.id,
   selector: '[mat-menu-item]',
   exportAs: 'matMenuItem',
-  inputs: ['disabled'],
+  inputs: ['disabled', 'disableRipple'],
   host: {
     'role': 'menuitem',
     'class': 'mat-menu-item',
@@ -47,8 +52,8 @@ export const _MatMenuItemMixinBase = mixinDisabled(MatMenuItemBase);
   preserveWhitespaces: false,
   templateUrl: 'menu-item.html',
 })
-export class MatMenuItem extends _MatMenuItemMixinBase implements FocusableOption, CanDisable,
-  OnDestroy {
+export class MatMenuItem extends _MatMenuItemMixinBase
+    implements FocusableOption, CanDisable, CanDisableRipple, OnDestroy {
 
   /** Stream that emits when the menu item is hovered. */
   _hovered: Subject<MatMenuItem> = new Subject();

src/lib/menu/menu.scss

@@ -82,4 +82,10 @@ button.mat-menu-item {
 
 .mat-menu-ripple {
   @include mat-fill;
+
+  // Prevent any pointer events on the ripple container for a menu item. The ripple container is
+  // not the trigger element for the ripples and can be therefore disabled like that. Disabling
+  // the pointer events ensures that there is no `click` event that can bubble up and cause
+  // the menu panel to close.
+  pointer-events: none;
 }

src/lib/menu/menu.spec.ts

@@ -26,7 +26,7 @@ import {
   MatMenuItem,
 } from './index';
 import {MENU_PANEL_TOP_PADDING} from './menu-trigger';
-import {extendObject} from '@angular/material/core';
+import {extendObject, MatRipple} from '@angular/material/core';
 import {
   dispatchKeyboardEvent,
   dispatchMouseEvent,
@@ -490,29 +490,43 @@ describe('MatMenu', () => {
   });
 
   describe('animations', () => {
-    it('should include the ripple on items by default', () => {
+    it('should enable ripples on items by default', () => {
       const fixture = TestBed.createComponent(SimpleMenu);
       fixture.detectChanges();
 
       fixture.componentInstance.trigger.openMenu();
+
       const item = fixture.debugElement.query(By.css('.mat-menu-item'));
-      const ripple = item.query(By.css('.mat-ripple'));
+      const ripple = item.query(By.css('.mat-ripple')).injector.get<MatRipple>(MatRipple);
 
-      expect(ripple).not.toBeNull();
+      expect(ripple.disabled).toBe(false);
     });
 
-    it('should remove the ripple on disabled items', () => {
+    it('should disable ripples on disabled items', () => {
       const fixture = TestBed.createComponent(SimpleMenu);
       fixture.detectChanges();
 
       fixture.componentInstance.trigger.openMenu();
+
+      // The second menu item in the `SimpleMenu` component is disabled.
       const items = fixture.debugElement.queryAll(By.css('.mat-menu-item'));
+      const ripple = items[1].query(By.css('.mat-ripple')).injector.get<MatRipple>(MatRipple);
 
-      // items[1] is disabled, so the ripple should not be present
-      const ripple = items[1].query(By.css('.mat-ripple'));
-      expect(ripple).toBeNull();
+      expect(ripple.disabled).toBe(true);
     });
 
+    it('should disable ripples if disableRipple is set', () => {
+      const fixture = TestBed.createComponent(SimpleMenu);
+      fixture.detectChanges();
+
+      fixture.componentInstance.trigger.openMenu();
+
+      // The third menu item in the `SimpleMenu` component has ripples disabled.
+      const items = fixture.debugElement.queryAll(By.css('.mat-menu-item'));
+      const ripple = items[2].query(By.css('.mat-ripple')).injector.get<MatRipple>(MatRipple);
+
+      expect(ripple.disabled).toBe(true);
+    });
   });
 
   describe('close event', () => {
@@ -1115,7 +1129,7 @@ describe('MatMenu default overrides', () => {
     <mat-menu class="custom-one custom-two" #menu="matMenu" (closed)="closeCallback($event)">
       <button mat-menu-item> Item </button>
       <button mat-menu-item disabled> Disabled </button>
-      <button mat-menu-item>
+      <button mat-menu-item disableRipple>
         <fake-icon>unicorn</fake-icon>
         Item with an icon
       </button>