feat($interval): add a service wrapping setInterval

The $interval service simplifies creating and testing recurring tasks.
This service does not increment $browser's outstanding request count,
which means that scenario tests and Protractor tests will not timeout
when a site uses a polling function registered by $interval. Provides
a workaround for #2402.

For unit tests, repeated tasks can be controlled using ngMock$interval's
tick(), tickNext(), and tickAll() functions.

angularFiles.js

@@ -20,6 +20,7 @@ angularFiles = {
  'src/ng/http.js',
  'src/ng/httpBackend.js',
  'src/ng/interpolate.js',
+ 'src/ng/interval.js',
  'src/ng/locale.js',
  'src/ng/location.js',
  'src/ng/log.js',

src/AngularPublic.js

@@ -114,6 +114,7 @@ function publishExternalAPI(angular){
  $exceptionHandler: $ExceptionHandlerProvider,
  $filter: $FilterProvider,
  $interpolate: $InterpolateProvider,
+ $interval: $IntervalProvider,
  $http: $HttpProvider,
  $httpBackend: $HttpBackendProvider,
  $location: $LocationProvider,

src/ng/interval.js

@@ -0,0 +1,90 @@
+'use strict';
+
+
+function $IntervalProvider() {
+ this.$get = ['$rootScope', '$window', '$q',
+ function($rootScope, $window, $q) {
+ var intervals = {};
+
+
+ /**
+ * @ngdoc function
+ * @name ng.$interval
+ *
+ * @description
+ * Angular's wrapper for `window.setInterval`. The `fn` function is executed every `delay`
+ * milliseconds.
+ *
+ * The return value of registering an interval function is a promise. This promise will be
+ * notified upon each tick of the interval, and will be resolved after `count` iterations, or
+ * run indefinitely if `count` is not defined. The value of the notification will be the
+ * number of iterations that have run.
+ * To cancel an interval, call `$interval.cancel(promise)`.
+ *
+ * In tests you can use {@link ngMock.$interval#flush `$interval.flush(millis)`} to
+ * move forward by `millis` milliseconds and trigger any functions scheduled to run in that
+ * time.
+ *
+ * @param {function()} fn A function that should be called repeatedly.
+ * @param {number} delay Number of milliseconds between each function call.
+ * @param {number=} [count=0] Number of times to repeat. If not set, or 0, will repeat
+ * indefinitely.
+ * @param {boolean=} [invokeApply=true] If set to `false` skips model dirty checking, otherwise
+ * will invoke `fn` within the {@link ng.$rootScope.Scope#$apply $apply} block.
+ * @returns {promise} A promise which will be notified on each iteration.
+ */
+ function interval(fn, delay, count, invokeApply) {
+ var setInterval = $window.setInterval,
+ clearInterval = $window.clearInterval;
+
+ var deferred = $q.defer(),
+ promise = deferred.promise,
+ count = (isDefined(count)) ? count : 0,
+ iteration = 0,
+ skipApply = (isDefined(invokeApply) && !invokeApply);
+
+ promise.then(null, null, fn);
+
+ promise.$$intervalId = setInterval(function tick() {
+ deferred.notify(iteration++);
+
+ if (count > 0 && iteration >= count) {
+ deferred.resolve(iteration);
+ clearInterval(promise.$$intervalId);
+ delete intervals[promise.$$intervalId];
+ }
+
+ if (!skipApply) $rootScope.$apply();
+
+ }, delay);
+
+ intervals[promise.$$intervalId] = deferred;
+
+ return promise;
+ }
+
+
+ /**
+ * @ngdoc function
+ * @name ng.$interval#cancel
+ * @methodOf ng.$interval
+ *
+ * @description
+ * Cancels a task associated with the `promise`.
+ *
+ * @param {number} promise Promise returned by the `$interval` function.
+ * @returns {boolean} Returns `true` if the task was successfully canceled.
+ */
+ interval.cancel = function(promise) {
+ if (promise && promise.$$intervalId in intervals) {
+ intervals[promise.$$intervalId].reject('canceled');
+ clearInterval(promise.$$intervalId);
+ delete intervals[promise.$$intervalId];
+ return true;
+ }
+ return false;
+ };
+
+ return interval;
+ }];
+}

src/ngMock/angular-mocks.js

@@ -438,6 +438,119 @@ angular.mock.$LogProvider = function() {
 };
 
 
+/**
+ * @ngdoc service
+ * @name ngMock.$interval
+ *
+ * @description
+ * Mock implementation of the $interval service.
+ *
+ * Use {@link ngMock.$interval#flush `$interval.flush(millis)`} to
+ * move forward by `millis` milliseconds and trigger any functions scheduled to run in that
+ * time.
+ *
+ * @param {function()} fn A function that should be called repeatedly.
+ * @param {number} delay Number of milliseconds between each function call.
+ * @param {number=} [count=0] Number of times to repeat. If not set, or 0, will repeat
+ * indefinitely.
+ * @param {boolean=} [invokeApply=true] If set to `false` skips model dirty checking, otherwise
+ * will invoke `fn` within the {@link ng.$rootScope.Scope#$apply $apply} block.
+ * @returns {promise} A promise which will be notified on each iteration.
+ */
+angular.mock.$IntervalProvider = function() {
+ this.$get = ['$rootScope', '$q',
+ function($rootScope, $q) {
+ var repeatFns = [],
+ nextRepeatId = 0,
+ now = 0;
+
+ var $interval = function(fn, delay, count, invokeApply) {
+ var deferred = $q.defer(),
+ promise = deferred.promise,
+ count = (isDefined(count)) ? count : 0,
+ iteration = 0,
+ skipApply = (isDefined(invokeApply) && !invokeApply);
+
+ promise.then(null, null, fn);
+
+ promise.$$intervalId = nextRepeatId;
+
+ function tick() {
+ deferred.notify(iteration++);
+
+ if (count > 0 && iteration >= count) {
+ var fnIndex;
+ deferred.resolve(iteration);
+
+ angular.forEach(repeatFns, function(fn, index) {
+ if (fn.id === promise.$$intervalId) fnIndex = index;
+ });
+
+ if (fnIndex !== undefined) {
+ repeatFns.splice(fnIndex, 1);
+ }
+ }
+
+ if (!skipApply) $rootScope.$apply();
+ };
+
+ repeatFns.push({
+ nextTime:(now + delay),
+ delay: delay,
+ fn: tick,
+ id: nextRepeatId,
+ deferred: deferred
+ });
+ repeatFns.sort(function(a,b){ return a.nextTime - b.nextTime;});
+
+ nextRepeatId++;
+ return promise;
+ };
+
+ $interval.cancel = function(promise) {
+ var fnIndex;
+
+ angular.forEach(repeatFns, function(fn, index) {
+ if (fn.id === promise.$$intervalId) fnIndex = index;
+ });
+
+ if (fnIndex !== undefined) {
+ repeatFns[fnIndex].deferred.reject('canceled');
+ repeatFns.splice(fnIndex, 1);
+ return true;
+ }
+
+ return false;
+ };
+
+ /**
+ * @ngdoc method
+ * @name ngMock.$interval#flush
+ * @methodOf ngMock.$interval
+ * @description
+ *
+ * Runs interval tasks scheduled to be run in the next `millis` milliseconds.
+ *
+ * @param {number=} millis maximum timeout amount to flush up until.
+ *
+ * @return {number} The amount of time moved forward.
+ */
+ $interval.flush = function(millis) {
+ now += millis;
+ while (repeatFns.length && repeatFns[0].nextTime <= now) {
+ var task = repeatFns[0];
+ task.fn();
+ task.nextTime += task.delay;
+ repeatFns.sort(function(a,b){ return a.nextTime - b.nextTime;});
+ }
+ return millis;
+ };
+
+ return $interval;
+ }];
+};
+
+
 (function() {
  var R_ISO8061_STR = /^(\d{4})-?(\d\d)-?(\d\d)(?:T(\d\d)(?:\:?(\d\d)(?:\:?(\d\d)(?:\.(\d{3}))?)?)?(Z|([+-])(\d\d):?(\d\d)))?$/;
 
@@ -1581,6 +1694,7 @@ angular.module('ngMock', ['ng']).provider({
  $browser: angular.mock.$BrowserProvider,
  $exceptionHandler: angular.mock.$ExceptionHandlerProvider,
  $log: angular.mock.$LogProvider,
+ $interval: angular.mock.$IntervalProvider,
  $httpBackend: angular.mock.$HttpBackendProvider,
  $rootElement: angular.mock.$RootElementProvider
 }).config(function($provide) {