fix($animateCss): properly handle cancellation timeouts for follow-up animations

Prior to this fix if `$animateCss` was called multiple on the same
element with new animation data then the preceeding fallback timout
would cause the animation to cancel midway. This fix ensures that
`$animateCss` can be triggered multiple times and only when the final
timeout has passed then all animations will be closed.

Closes angular#12359

Author: matsko

Diff for: src/ngAnimate/animateCss.js

@@ -1,5 +1,7 @@
 'use strict';
 
+var ANIMATE_TIMER_KEY = '$$animateCss';
+
 /**
  * @ngdoc service
  * @name $animateCss
@@ -861,17 +863,41 @@ var $AnimateCssProvider = ['$animateProvider', function($animateProvider) {
           }
 
           startTime = Date.now();
-          element.on(events.join(' '), onAnimationProgress);
-          $timeout(onAnimationExpired, maxDelayTime + CLOSING_TIME_BUFFER * maxDurationTime, false);
+          var timerTime = maxDelayTime + CLOSING_TIME_BUFFER * maxDurationTime;
+          var endTime = startTime + timerTime;
+
+          var animationsData = element.data(ANIMATE_TIMER_KEY) || [];
+          var setupFallbackTimer = true;
+          if (animationsData.length) {
+            var currentTimerData = animationsData[0];
+            setupFallbackTimer = endTime > currentTimerData.expectedEndTime;
+            if (setupFallbackTimer) {
+              $timeout.cancel(currentTimerData.timer);
+            } else {
+              animationsData.push(close);
+            }
+          }
 
+          if (setupFallbackTimer) {
+            var timer = $timeout(onAnimationExpired, timerTime, false);
+            animationsData[0] = {
+              timer: timer,
+              expectedEndTime: endTime
+            };
+            animationsData.push(close);
+            element.data(ANIMATE_TIMER_KEY, animationsData);
+          }
+
+          element.on(events.join(' '), onAnimationProgress);
           applyAnimationToStyles(element, options);
         }
 
         function onAnimationExpired() {
-          // although an expired animation is a failed animation, getting to
-          // this outcome is very easy if the CSS code screws up. Therefore we
-          // should still continue normally as if the animation completed correctly.
-          close();
+          var animationsData = element.data(ANIMATE_TIMER_KEY);
+          for (var i = 1; i < animationsData.length; i++) {
+            animationsData[i]();
+          }
+          element.removeData(ANIMATE_TIMER_KEY);
         }
 
         function onAnimationProgress(event) {

Diff for: test/ngAnimate/animateCssSpec.js

@@ -1135,6 +1135,62 @@ describe("ngAnimate $animateCss", function() {
           expect(passed).toBe(true);
           expect(failed).not.toBe(true);
         }));
+
+        it("should close all stacked animations after the last timeout runs on the same element",
+          inject(function($animateCss, $$body, $rootElement, $timeout) {
+
+          var now = 0;
+          spyOn(Date, 'now').andCallFake(function() {
+            return now;
+          });
+
+          var cancelSpy = spyOn($timeout, 'cancel').andCallThrough();
+          var doneSpy = jasmine.createSpy();
+
+          ss.addRule('.elm', 'transition:1s linear all;');
+          ss.addRule('.elm.red', 'background:red;');
+          ss.addRule('.elm.blue', 'transition:2s linear all; background:blue;');
+          ss.addRule('.elm.green', 'background:green;');
+
+          var element = jqLite('<div class="elm"></div>');
+          $rootElement.append(element);
+          $$body.append($rootElement);
+
+          // timeout will be at 1500s
+          animate(element, 'red', doneSpy);
+          expect(doneSpy).not.toHaveBeenCalled();
+
+          fastForwardClock(500); //1000s left to go
+
+          // timeout will not be at 500 + 3000s = 3500s
+          animate(element, 'blue', doneSpy);
+          expect(doneSpy).not.toHaveBeenCalled();
+          expect(cancelSpy).toHaveBeenCalled();
+
+          cancelSpy.reset();
+
+          // timeout will not be set again since the former animation is longer
+          animate(element, 'green', doneSpy);
+          expect(doneSpy).not.toHaveBeenCalled();
+          expect(cancelSpy).not.toHaveBeenCalled();
+
+          // this will close the animations fully
+          fastForwardClock(3500);
+          expect(doneSpy).toHaveBeenCalled();
+          expect(doneSpy.callCount).toBe(3);
+
+          function fastForwardClock(time) {
+            now += time;
+            $timeout.flush(time);
+          }
+
+          function animate(element, klass, onDone) {
+            var animator = $animateCss(element, { addClass: klass }).start();
+            animator.done(onDone);
+            triggerAnimationStartFrame();
+            return animator;
+          }
+        }));
       });
 
       describe("getComputedStyle", function() {