fix(ripple): not fading out on touch devices

* Makes the ripple animations no longer dependent on `setTimeout` that does not always fire properly / or within the specified duration. (related chrome issue: https://bugs.chromium.org/p/chromium/issues/detail?id=567800)
* Fix indentation of a few ripple tests
* Fixes that the speed factor tests are basically not checking anything (even though they will be removed in the future; they need to pass right now)

Fixes #12470

Author: devversion

src/material-experimental/mdc-list/list.spec.ts

@@ -1,14 +1,10 @@
 import {waitForAsync, TestBed, fakeAsync, tick} from '@angular/core/testing';
 import {Component, QueryList, ViewChildren} from '@angular/core';
-import {defaultRippleAnimationConfig} from '@angular/material/core';
-import {dispatchMouseEvent} from '@angular/cdk/testing/private';
+import {dispatchFakeEvent, dispatchMouseEvent} from '@angular/cdk/testing/private';
 import {By} from '@angular/platform-browser';
 import {MatListItem, MatListModule} from './index';
 
 describe('MDC-based MatList', () => {
-  // Default ripple durations used for testing.
-  const {enterDuration, exitDuration} = defaultRippleAnimationConfig;
-
   beforeEach(waitForAsync(() => {
     TestBed.configureTestingModule({
       imports: [MatListModule],
@@ -230,11 +226,15 @@ describe('MDC-based MatList', () => {
       dispatchMouseEvent(rippleTarget, 'mousedown');
       dispatchMouseEvent(rippleTarget, 'mouseup');
 
+      // Flush the ripple enter animation.
+      dispatchFakeEvent(rippleTarget.querySelector('.mat-ripple-element')!, 'transitionend');
+
       expect(rippleTarget.querySelectorAll('.mat-ripple-element').length)
         .toBe(1, 'Expected ripples to be enabled by default.');
 
-      // Wait for the ripples to go away.
-      tick(enterDuration + exitDuration);
+      // Flush the ripple exit animation.
+      dispatchFakeEvent(rippleTarget.querySelector('.mat-ripple-element')!, 'transitionend');
+
       expect(rippleTarget.querySelectorAll('.mat-ripple-element').length)
         .toBe(0, 'Expected ripples to go away.');
 
@@ -258,11 +258,15 @@ describe('MDC-based MatList', () => {
       dispatchMouseEvent(rippleTarget, 'mousedown');
       dispatchMouseEvent(rippleTarget, 'mouseup');
 
+      // Flush the ripple enter animation.
+      dispatchFakeEvent(rippleTarget.querySelector('.mat-ripple-element')!, 'transitionend');
+
       expect(rippleTarget.querySelectorAll('.mat-ripple-element').length)
         .toBe(1, 'Expected ripples to be enabled by default.');
 
-      // Wait for the ripples to go away.
-      tick(enterDuration + exitDuration);
+      // Flush the ripple exit animation.
+      dispatchFakeEvent(rippleTarget.querySelector('.mat-ripple-element')!, 'transitionend');
+
       expect(rippleTarget.querySelectorAll('.mat-ripple-element').length)
         .toBe(0, 'Expected ripples to go away.');
 

src/material-experimental/mdc-list/selection-list.spec.ts

@@ -22,7 +22,7 @@ import {
   tick,
 } from '@angular/core/testing';
 import {FormControl, FormsModule, NgModel, ReactiveFormsModule} from '@angular/forms';
-import {defaultRippleAnimationConfig, ThemePalette} from '@angular/material/core';
+import {ThemePalette} from '@angular/material/core';
 import {By} from '@angular/platform-browser';
 import {numbers} from '@material/list';
 import {MatListModule, MatListOption, MatSelectionList, MatSelectionListChange} from './index';
@@ -695,16 +695,18 @@ describe('MDC-based MatSelectionList without forms', () => {
       fakeAsync(() => {
         const rippleTarget = fixture.nativeElement
           .querySelector('.mat-mdc-list-option:not(.mdc-list-item--disabled)');
-        const {enterDuration, exitDuration} = defaultRippleAnimationConfig;
-
         dispatchMouseEvent(rippleTarget, 'mousedown');
         dispatchMouseEvent(rippleTarget, 'mouseup');
 
+        // Flush the ripple enter animation.
+        dispatchFakeEvent(rippleTarget.querySelector('.mat-ripple-element')!, 'transitionend');
+
         expect(rippleTarget.querySelectorAll('.mat-ripple-element').length)
           .toBe(1, 'Expected ripples to be enabled by default.');
 
-        // Wait for the ripples to go away.
-        tick(enterDuration + exitDuration);
+        // Flush the ripple exit animation.
+        dispatchFakeEvent(rippleTarget.querySelector('.mat-ripple-element')!, 'transitionend');
+
         expect(rippleTarget.querySelectorAll('.mat-ripple-element').length)
           .toBe(0, 'Expected ripples to go away.');
 

src/material/core/ripple/ripple-renderer.ts

@@ -150,21 +150,19 @@ export class RippleRenderer implements EventListenerObject {
       this._mostRecentTransientRipple = rippleRef;
     }
 
-    // Wait for the ripple element to be completely faded in.
-    // Once it's faded in, the ripple can be hidden immediately if the mouse is released.
-    this._runTimeoutOutsideZone(() => {
-      const isMostRecentTransientRipple = rippleRef === this._mostRecentTransientRipple;
-
-      rippleRef.state = RippleState.VISIBLE;
-
-      // When the timer runs out while the user has kept their pointer down, we want to
-      // keep only the persistent ripples and the latest transient ripple. We do this,
-      // because we don't want stacked transient ripples to appear after their enter
-      // animation has finished.
-      if (!config.persistent && (!isMostRecentTransientRipple || !this._isPointerDown)) {
-        rippleRef.fadeOut();
-      }
-    }, duration);
+    // Do not register the `transition` event listener if fade-in and fade-out duration
+    // are set to zero. The events won't fire anyway and we can save resources here.
+    if (duration || animationConfig.exitDuration) {
+      this._ngZone.runOutsideAngular(() => {
+        ripple.addEventListener('transitionend', () => this._finishRippleTransition(rippleRef));
+      });
+    }
+
+    // In case there is no fade-in transition duration, we need to manually call the transition
+    // end listener because `transitionend` doesn't fire if there is no transition.
+    if (!duration) {
+      this._finishRippleTransition(rippleRef);
+    }
 
     return rippleRef;
   }
@@ -190,15 +188,17 @@ export class RippleRenderer implements EventListenerObject {
     const rippleEl = rippleRef.element;
     const animationConfig = {...defaultRippleAnimationConfig, ...rippleRef.config.animation};
 
+    // This starts the fade-out transition and will fire the transition end listener that
+    // removes the ripple element from the DOM.
     rippleEl.style.transitionDuration = `${animationConfig.exitDuration}ms`;
     rippleEl.style.opacity = '0';
     rippleRef.state = RippleState.FADING_OUT;
 
-    // Once the ripple faded out, the ripple can be safely removed from the DOM.
-    this._runTimeoutOutsideZone(() => {
-      rippleRef.state = RippleState.HIDDEN;
-      rippleEl.parentNode!.removeChild(rippleEl);
-    }, animationConfig.exitDuration);
+    // In case there is no fade-out transition duration, we need to manually call the
+    // transition end listener because `transitionend` doesn't fire if there is no transition.
+    if (!animationConfig.exitDuration) {
+      this._finishRippleTransition(rippleRef);
+    }
   }
 
   /** Fades out all currently active ripples. */
@@ -243,6 +243,40 @@ export class RippleRenderer implements EventListenerObject {
     }
   }
 
+  /** Method that will be called if the fade-in or fade-in transition completed. */
+  private _finishRippleTransition(rippleRef: RippleRef) {
+    if (rippleRef.state === RippleState.FADING_IN) {
+      this._startFadeOutTransition(rippleRef);
+    } else if (rippleRef.state === RippleState.FADING_OUT) {
+      this._destroyRipple(rippleRef);
+    }
+  }
+
+  /**
+   * Starts the fade-out transition of the given ripple if it's not persistent and the pointer
+   * is not held down anymore.
+   */
+  private _startFadeOutTransition(rippleRef: RippleRef) {
+    const isMostRecentTransientRipple = rippleRef === this._mostRecentTransientRipple;
+    const {persistent} = rippleRef.config;
+
+    rippleRef.state = RippleState.VISIBLE;
+
+    // When the timer runs out while the user has kept their pointer down, we want to
+    // keep only the persistent ripples and the latest transient ripple. We do this,
+    // because we don't want stacked transient ripples to appear after their enter
+    // animation has finished.
+    if (!persistent && (!isMostRecentTransientRipple || !this._isPointerDown)) {
+      rippleRef.fadeOut();
+    }
+  }
+
+  /** Destroys the given ripple by removing it from the DOM and updating its state. */
+  private _destroyRipple(rippleRef: RippleRef) {
+    rippleRef.state = RippleState.HIDDEN;
+    rippleRef.element.parentNode!.removeChild(rippleRef.element);
+  }
+
   /** Function being called whenever the trigger is being pressed using mouse. */
   private _onMousedown(event: MouseEvent) {
     // Screen readers will fire fake mouse events for space/enter. Skip launching a
@@ -297,11 +331,6 @@ export class RippleRenderer implements EventListenerObject {
     });
   }
 
-  /** Runs a timeout outside of the Angular zone to avoid triggering the change detection. */
-  private _runTimeoutOutsideZone(fn: Function, delay = 0) {
-    this._ngZone.runOutsideAngular(() => setTimeout(fn, delay));
-  }
-
   /** Registers event listeners for a given list of events. */
   private _registerEvents(eventTypes: string[]) {
     this._ngZone.runOutsideAngular(() => {