'use strict'; /** * DESIGN NOTES * * The design decisions behind the scope are heavily favored for speed and memory consumption. * * The typical use of scope is to watch the expressions, which most of the time return the same * value as last time so we optimize the operation. * * Closures construction is expensive in terms of speed as well as memory: * - No closures, instead use prototypical inheritance for API * - Internal state needs to be stored on scope directly, which means that private state is * exposed as $$____ properties * * Loop operations are optimized by using while(count--) { ... } * - This means that in order to keep the same order of execution as addition we have to add * items to the array at the beginning (unshift) instead of at the end (push) * * Child scopes are created and removed often * - Using an array would be slow since inserts in the middle are expensive; so we use linked lists * * There are fewer watches than observers. This is why you don't want the observer to be implemented * in the same way as watch. Watch requires return of the initialization function which is expensive * to construct. */ /** * @ngdoc provider * @name $rootScopeProvider * @description * * Provider for the $rootScope service. */ /** * @ngdoc method * @name $rootScopeProvider#digestTtl * @description * * Sets the number of `$digest` iterations the scope should attempt to execute before giving up and * assuming that the model is unstable. * * The current default is 10 iterations. * * In complex applications it's possible that the dependencies between `$watch`s will result in * several digest iterations. However if an application needs more than the default 10 digest * iterations for its model to stabilize then you should investigate what is causing the model to * continuously change during the digest. * * Increasing the TTL could have performance implications, so you should not change it without * proper justification. * * @param {number} limit The number of digest iterations. */ /** * @ngdoc service * @name $rootScope * @this * * @description * * Every application has a single root {@link ng.$rootScope.Scope scope}. * All other scopes are descendant scopes of the root scope. Scopes provide separation * between the model and the view, via a mechanism for watching the model for changes. * They also provide event emission/broadcast and subscription facility. See the * {@link guide/scope developer guide on scopes}. */ function $RootScopeProvider() { var TTL = 10; var $rootScopeMinErr = minErr('$rootScope'); var lastDirtyWatch = null; var applyAsyncId = null; this.digestTtl = function(value) { if (arguments.length) { TTL = value; } return TTL; }; function createChildScopeClass(parent) { function ChildScope() { this.$$watchers = this.$$nextSibling = this.$$childHead = this.$$childTail = null; this.$$listeners = {}; this.$$listenerCount = {}; this.$$watchersCount = 0; this.$id = nextUid(); this.$$ChildScope = null; } ChildScope.prototype = parent; return ChildScope; } this.$get = ['$exceptionHandler', '$parse', '$browser', function($exceptionHandler, $parse, $browser) { function destroyChildScope($event) { $event.currentScope.$$destroyed = true; } function cleanUpScope($scope) { // Support: IE 9 only if (msie === 9) { // There is a memory leak in IE9 if all child scopes are not disconnected // completely when a scope is destroyed. So this code will recurse up through // all this scopes children // // See issue https://github.com/angular/angular.js/issues/10706 if ($scope.$$childHead) { cleanUpScope($scope.$$childHead); } if ($scope.$$nextSibling) { cleanUpScope($scope.$$nextSibling); } } // The code below works around IE9 and V8's memory leaks // // See: // - https://code.google.com/p/v8/issues/detail?id=2073#c26 // - https://github.com/angular/angular.js/issues/6794#issuecomment-38648909 // - https://github.com/angular/angular.js/issues/1313#issuecomment-10378451 $scope.$parent = $scope.$$nextSibling = $scope.$$prevSibling = $scope.$$childHead = $scope.$$childTail = $scope.$root = $scope.$$watchers = null; } /** * @ngdoc type * @name $rootScope.Scope * * @description * A root scope can be retrieved using the {@link ng.$rootScope $rootScope} key from the * {@link auto.$injector $injector}. Child scopes are created using the * {@link ng.$rootScope.Scope#$new $new()} method. (Most scopes are created automatically when * compiled HTML template is executed.) See also the {@link guide/scope Scopes guide} for * an in-depth introduction and usage examples. * * * # Inheritance * A scope can inherit from a parent scope, as in this example: * ```js var parent = $rootScope; var child = parent.$new(); parent.salutation = "Hello"; expect(child.salutation).toEqual('Hello'); child.salutation = "Welcome"; expect(child.salutation).toEqual('Welcome'); expect(parent.salutation).toEqual('Hello'); * ``` * * When interacting with `Scope` in tests, additional helper methods are available on the * instances of `Scope` type. See {@link ngMock.$rootScope.Scope ngMock Scope} for additional * details. * * * @param {Object.=} providers Map of service factory which need to be * provided for the current scope. Defaults to {@link ng}. * @param {Object.=} instanceCache Provides pre-instantiated services which should * append/override services provided by `providers`. This is handy * when unit-testing and having the need to override a default * service. * @returns {Object} Newly created scope. * */ function Scope() { this.$id = nextUid(); this.$$phase = this.$parent = this.$$watchers = this.$$nextSibling = this.$$prevSibling = this.$$childHead = this.$$childTail = null; this.$root = this; this.$$destroyed = false; this.$$listeners = {}; this.$$listenerCount = {}; this.$$watchersCount = 0; this.$$isolateBindings = null; } /** * @ngdoc property * @name $rootScope.Scope#$id * * @description * Unique scope ID (monotonically increasing) useful for debugging. */ /** * @ngdoc property * @name $rootScope.Scope#$parent * * @description * Reference to the parent scope. */ /** * @ngdoc property * @name $rootScope.Scope#$root * * @description * Reference to the root scope. */ Scope.prototype = { constructor: Scope, /** * @ngdoc method * @name $rootScope.Scope#$new * @kind function * * @description * Creates a new child {@link ng.$rootScope.Scope scope}. * * The parent scope will propagate the {@link ng.$rootScope.Scope#$digest $digest()} event. * The scope can be removed from the scope hierarchy using {@link ng.$rootScope.Scope#$destroy $destroy()}. * * {@link ng.$rootScope.Scope#$destroy $destroy()} must be called on a scope when it is * desired for the scope and its child scopes to be permanently detached from the parent and * thus stop participating in model change detection and listener notification by invoking. * * @param {boolean} isolate If true, then the scope does not prototypically inherit from the * parent scope. The scope is isolated, as it can not see parent scope properties. * When creating widgets, it is useful for the widget to not accidentally read parent * state. * * @param {Scope} [parent=this] The {@link ng.$rootScope.Scope `Scope`} that will be the `$parent` * of the newly created scope. Defaults to `this` scope if not provided. * This is used when creating a transclude scope to correctly place it * in the scope hierarchy while maintaining the correct prototypical * inheritance. * * @returns {Object} The newly created child scope. * */ $new: function(isolate, parent) { var child; parent = parent || this; if (isolate) { child = new Scope(); child.$root = this.$root; } else { // Only create a child scope class if somebody asks for one, // but cache it to allow the VM to optimize lookups. if (!this.$$ChildScope) { this.$$ChildScope = createChildScopeClass(this); } child = new this.$$ChildScope(); } child.$parent = parent; child.$$prevSibling = parent.$$childTail; if (parent.$$childHead) { parent.$$childTail.$$nextSibling = child; parent.$$childTail = child; } else { parent.$$childHead = parent.$$childTail = child; } // When the new scope is not isolated or we inherit from `this`, and // the parent scope is destroyed, the property `$$destroyed` is inherited // prototypically. In all other cases, this property needs to be set // when the parent scope is destroyed. // The listener needs to be added after the parent is set if (isolate || parent !== this) child.$on('$destroy', destroyChildScope); return child; }, /** * @ngdoc method * @name $rootScope.Scope#$watch * @kind function * * @description * Registers a `listener` callback to be executed whenever the `watchExpression` changes. * * - The `watchExpression` is called on every call to {@link ng.$rootScope.Scope#$digest * $digest()} and should return the value that will be watched. (`watchExpression` should not change * its value when executed multiple times with the same input because it may be executed multiple * times by {@link ng.$rootScope.Scope#$digest $digest()}. That is, `watchExpression` should be * [idempotent](http://en.wikipedia.org/wiki/Idempotence).) * - The `listener` is called only when the value from the current `watchExpression` and the * previous call to `watchExpression` are not equal (with the exception of the initial run, * see below). Inequality is determined according to reference inequality, * [strict comparison](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Comparison_Operators) * via the `!==` Javascript operator, unless `objectEquality == true` * (see next point) * - When `objectEquality == true`, inequality of the `watchExpression` is determined * according to the {@link angular.equals} function. To save the value of the object for * later comparison, the {@link angular.copy} function is used. This therefore means that * watching complex objects will have adverse memory and performance implications. * - This should not be used to watch for changes in objects that are * or contain [File](https://developer.mozilla.org/docs/Web/API/File) objects due to limitations with {@link angular.copy `angular.copy`}. * - The watch `listener` may change the model, which may trigger other `listener`s to fire. * This is achieved by rerunning the watchers until no changes are detected. The rerun * iteration limit is 10 to prevent an infinite loop deadlock. * * * If you want to be notified whenever {@link ng.$rootScope.Scope#$digest $digest} is called, * you can register a `watchExpression` function with no `listener`. (Be prepared for * multiple calls to your `watchExpression` because it will execute multiple times in a * single {@link ng.$rootScope.Scope#$digest $digest} cycle if a change is detected.) * * After a watcher is registered with the scope, the `listener` fn is called asynchronously * (via {@link ng.$rootScope.Scope#$evalAsync $evalAsync}) to initialize the * watcher. In rare cases, this is undesirable because the listener is called when the result * of `watchExpression` didn't change. To detect this scenario within the `listener` fn, you * can compare the `newVal` and `oldVal`. If these two values are identical (`===`) then the * listener was called due to initialization. * * * * # Example * ```js // let's assume that scope was dependency injected as the $rootScope var scope = $rootScope; scope.name = 'misko'; scope.counter = 0; expect(scope.counter).toEqual(0); scope.$watch('name', function(newValue, oldValue) { scope.counter = scope.counter + 1; }); expect(scope.counter).toEqual(0); scope.$digest(); // the listener is always called during the first $digest loop after it was registered expect(scope.counter).toEqual(1); scope.$digest(); // but now it will not be called unless the value changes expect(scope.counter).toEqual(1); scope.name = 'adam'; scope.$digest(); expect(scope.counter).toEqual(2); // Using a function as a watchExpression var food; scope.foodCounter = 0; expect(scope.foodCounter).toEqual(0); scope.$watch( // This function returns the value being watched. It is called for each turn of the $digest loop function() { return food; }, // This is the change listener, called when the value returned from the above function changes function(newValue, oldValue) { if ( newValue !== oldValue ) { // Only increment the counter if the value changed scope.foodCounter = scope.foodCounter + 1; } } ); // No digest has been run so the counter will be zero expect(scope.foodCounter).toEqual(0); // Run the digest but since food has not changed count will still be zero scope.$digest(); expect(scope.foodCounter).toEqual(0); // Update food and run digest. Now the counter will increment food = 'cheeseburger'; scope.$digest(); expect(scope.foodCounter).toEqual(1); * ``` * * * * @param {(function()|string)} watchExpression Expression that is evaluated on each * {@link ng.$rootScope.Scope#$digest $digest} cycle. A change in the return value triggers * a call to the `listener`. * * - `string`: Evaluated as {@link guide/expression expression} * - `function(scope)`: called with current `scope` as a parameter. * @param {function(newVal, oldVal, scope)} listener Callback called whenever the value * of `watchExpression` changes. * * - `newVal` contains the current value of the `watchExpression` * - `oldVal` contains the previous value of the `watchExpression` * - `scope` refers to the current scope * @param {boolean=} [objectEquality=false] Compare for object equality using {@link angular.equals} instead of * comparing for reference equality. * @returns {function()} Returns a deregistration function for this listener. */ $watch: function(watchExp, listener, objectEquality, prettyPrintExpression) { var get = $parse(watchExp); if (get.$$watchDelegate) { return get.$$watchDelegate(this, listener, objectEquality, get, watchExp); } var scope = this, array = scope.$$watchers, watcher = { fn: listener, last: initWatchVal, get: get, exp: prettyPrintExpression || watchExp, eq: !!objectEquality }; lastDirtyWatch = null; if (!isFunction(listener)) { watcher.fn = noop; } if (!array) { array = scope.$$watchers = []; array.$$digestWatchIndex = -1; } // we use unshift since we use a while loop in $digest for speed. // the while loop reads in reverse order. array.unshift(watcher); array.$$digestWatchIndex++; incrementWatchersCount(this, 1); return function deregisterWatch() { var index = arrayRemove(array, watcher); if (index >= 0) { incrementWatchersCount(scope, -1); if (index < array.$$digestWatchIndex) { array.$$digestWatchIndex--; } } lastDirtyWatch = null; }; }, /** * @ngdoc method * @name $rootScope.Scope#$watchGroup * @kind function * * @description * A variant of {@link ng.$rootScope.Scope#$watch $watch()} where it watches an array of `watchExpressions`. * If any one expression in the collection changes the `listener` is executed. * * - The items in the `watchExpressions` array are observed via the standard `$watch` operation. Their return * values are examined for changes on every call to `$digest`. * - The `listener` is called whenever any expression in the `watchExpressions` array changes. * * @param {Array.} watchExpressions Array of expressions that will be individually * watched using {@link ng.$rootScope.Scope#$watch $watch()} * * @param {function(newValues, oldValues, scope)} listener Callback called whenever the return value of any * expression in `watchExpressions` changes * The `newValues` array contains the current values of the `watchExpressions`, with the indexes matching * those of `watchExpression` * and the `oldValues` array contains the previous values of the `watchExpressions`, with the indexes matching * those of `watchExpression` * The `scope` refers to the current scope. * @returns {function()} Returns a de-registration function for all listeners. */ $watchGroup: function(watchExpressions, listener) { var oldValues = new Array(watchExpressions.length); var newValues = new Array(watchExpressions.length); var deregisterFns = []; var self = this; var changeReactionScheduled = false; var firstRun = true; if (!watchExpressions.length) { // No expressions means we call the listener ASAP var shouldCall = true; self.$evalAsync(function() { if (shouldCall) listener(newValues, newValues, self); }); return function deregisterWatchGroup() { shouldCall = false; }; } if (watchExpressions.length === 1) { // Special case size of one return this.$watch(watchExpressions[0], function watchGroupAction(value, oldValue, scope) { newValues[0] = value; oldValues[0] = oldValue; listener(newValues, (value === oldValue) ? newValues : oldValues, scope); }); } forEach(watchExpressions, function(expr, i) { var unwatchFn = self.$watch(expr, function watchGroupSubAction(value) { newValues[i] = value; if (!changeReactionScheduled) { changeReactionScheduled = true; self.$evalAsync(watchGroupAction); } }); deregisterFns.push(unwatchFn); }); function watchGroupAction() { changeReactionScheduled = false; try { if (firstRun) { firstRun = false; listener(newValues, newValues, self); } else { listener(newValues, oldValues, self); } } finally { for (var i = 0; i < watchExpressions.length; i++) { oldValues[i] = newValues[i]; } } } return function deregisterWatchGroup() { while (deregisterFns.length) { deregisterFns.shift()(); } }; }, /** * @ngdoc method * @name $rootScope.Scope#$watchCollection * @kind function * * @description * Shallow watches the properties of an object and fires whenever any of the properties change * (for arrays, this implies watching the array items; for object maps, this implies watching * the properties). If a change is detected, the `listener` callback is fired. * * - The `obj` collection is observed via standard $watch operation and is examined on every * call to $digest() to see if any items have been added, removed, or moved. * - The `listener` is called whenever anything within the `obj` has changed. Examples include * adding, removing, and moving items belonging to an object or array. * * * # Example * ```js $scope.names = ['igor', 'matias', 'misko', 'james']; $scope.dataCount = 4; $scope.$watchCollection('names', function(newNames, oldNames) { $scope.dataCount = newNames.length; }); expect($scope.dataCount).toEqual(4); $scope.$digest(); //still at 4 ... no changes expect($scope.dataCount).toEqual(4); $scope.names.pop(); $scope.$digest(); //now there's been a change expect($scope.dataCount).toEqual(3); * ``` * * * @param {string|function(scope)} obj Evaluated as {@link guide/expression expression}. The * expression value should evaluate to an object or an array which is observed on each * {@link ng.$rootScope.Scope#$digest $digest} cycle. Any shallow change within the * collection will trigger a call to the `listener`. * * @param {function(newCollection, oldCollection, scope)} listener a callback function called * when a change is detected. * - The `newCollection` object is the newly modified data obtained from the `obj` expression * - The `oldCollection` object is a copy of the former collection data. * Due to performance considerations, the`oldCollection` value is computed only if the * `listener` function declares two or more arguments. * - The `scope` argument refers to the current scope. * * @returns {function()} Returns a de-registration function for this listener. When the * de-registration function is executed, the internal watch operation is terminated. */ $watchCollection: function(obj, listener) { $watchCollectionInterceptor.$stateful = true; var self = this; // the current value, updated on each dirty-check run var newValue; // a shallow copy of the newValue from the last dirty-check run, // updated to match newValue during dirty-check run var oldValue; // a shallow copy of the newValue from when the last change happened var veryOldValue; // only track veryOldValue if the listener is asking for it var trackVeryOldValue = (listener.length > 1); var changeDetected = 0; var changeDetector = $parse(obj, $watchCollectionInterceptor); var internalArray = []; var internalObject = {}; var initRun = true; var oldLength = 0; function $watchCollectionInterceptor(_value) { newValue = _value; var newLength, key, bothNaN, newItem, oldItem; // If the new value is undefined, then return undefined as the watch may be a one-time watch if (isUndefined(newValue)) return; if (!isObject(newValue)) { // if primitive if (oldValue !== newValue) { oldValue = newValue; changeDetected++; } } else if (isArrayLike(newValue)) { if (oldValue !== internalArray) { // we are transitioning from something which was not an array into array. oldValue = internalArray; oldLength = oldValue.length = 0; changeDetected++; } newLength = newValue.length; if (oldLength !== newLength) { // if lengths do not match we need to trigger change notification changeDetected++; oldValue.length = oldLength = newLength; } // copy the items to oldValue and look for changes. for (var i = 0; i < newLength; i++) { oldItem = oldValue[i]; newItem = newValue[i]; // eslint-disable-next-line no-self-compare bothNaN = (oldItem !== oldItem) && (newItem !== newItem); if (!bothNaN && (oldItem !== newItem)) { changeDetected++; oldValue[i] = newItem; } } } else { if (oldValue !== internalObject) { // we are transitioning from something which was not an object into object. oldValue = internalObject = {}; oldLength = 0; changeDetected++; } // copy the items to oldValue and look for changes. newLength = 0; for (key in newValue) { if (hasOwnProperty.call(newValue, key)) { newLength++; newItem = newValue[key]; oldItem = oldValue[key]; if (key in oldValue) { // eslint-disable-next-line no-self-compare bothNaN = (oldItem !== oldItem) && (newItem !== newItem); if (!bothNaN && (oldItem !== newItem)) { changeDetected++; oldValue[key] = newItem; } } else { oldLength++; oldValue[key] = newItem; changeDetected++; } } } if (oldLength > newLength) { // we used to have more keys, need to find them and destroy them. changeDetected++; for (key in oldValue) { if (!hasOwnProperty.call(newValue, key)) { oldLength--; delete oldValue[key]; } } } } return changeDetected; } function $watchCollectionAction() { if (initRun) { initRun = false; listener(newValue, newValue, self); } else { listener(newValue, veryOldValue, self); } // make a copy for the next time a collection is changed if (trackVeryOldValue) { if (!isObject(newValue)) { //primitive veryOldValue = newValue; } else if (isArrayLike(newValue)) { veryOldValue = new Array(newValue.length); for (var i = 0; i < newValue.length; i++) { veryOldValue[i] = newValue[i]; } } else { // if object veryOldValue = {}; for (var key in newValue) { if (hasOwnProperty.call(newValue, key)) { veryOldValue[key] = newValue[key]; } } } } } return this.$watch(changeDetector, $watchCollectionAction); }, /** * @ngdoc method * @name $rootScope.Scope#$digest * @kind function * * @description * Processes all of the {@link ng.$rootScope.Scope#$watch watchers} of the current scope and * its children. Because a {@link ng.$rootScope.Scope#$watch watcher}'s listener can change * the model, the `$digest()` keeps calling the {@link ng.$rootScope.Scope#$watch watchers} * until no more listeners are firing. This means that it is possible to get into an infinite * loop. This function will throw `'Maximum iteration limit exceeded.'` if the number of * iterations exceeds 10. * * Usually, you don't call `$digest()` directly in * {@link ng.directive:ngController controllers} or in * {@link ng.$compileProvider#directive directives}. * Instead, you should call {@link ng.$rootScope.Scope#$apply $apply()} (typically from within * a {@link ng.$compileProvider#directive directive}), which will force a `$digest()`. * * If you want to be notified whenever `$digest()` is called, * you can register a `watchExpression` function with * {@link ng.$rootScope.Scope#$watch $watch()} with no `listener`. * * In unit tests, you may need to call `$digest()` to simulate the scope life cycle. * * # Example * ```js var scope = ...; scope.name = 'misko'; scope.counter = 0; expect(scope.counter).toEqual(0); scope.$watch('name', function(newValue, oldValue) { scope.counter = scope.counter + 1; }); expect(scope.counter).toEqual(0); scope.$digest(); // the listener is always called during the first $digest loop after it was registered expect(scope.counter).toEqual(1); scope.$digest(); // but now it will not be called unless the value changes expect(scope.counter).toEqual(1); scope.name = 'adam'; scope.$digest(); expect(scope.counter).toEqual(2); * ``` * */ $digest: function() { var watch, value, last, fn, get, watchers, dirty, ttl = TTL, next, current, target = this, watchLog = [], logIdx, asyncTask; beginPhase('$digest'); // Check for changes to browser url that happened in sync before the call to $digest $browser.$$checkUrlChange(); if (this === $rootScope && applyAsyncId !== null) { // If this is the root scope, and $applyAsync has scheduled a deferred $apply(), then // cancel the scheduled $apply and flush the queue of expressions to be evaluated. $browser.defer.cancel(applyAsyncId); flushApplyAsync(); } lastDirtyWatch = null; do { // "while dirty" loop dirty = false; current = target; // It's safe for asyncQueuePosition to be a local variable here because this loop can't // be reentered recursively. Calling $digest from a function passed to $evalAsync would // lead to a '$digest already in progress' error. for (var asyncQueuePosition = 0; asyncQueuePosition < asyncQueue.length; asyncQueuePosition++) { try { asyncTask = asyncQueue[asyncQueuePosition]; fn = asyncTask.fn; fn(asyncTask.scope, asyncTask.locals); } catch (e) { $exceptionHandler(e); } lastDirtyWatch = null; } asyncQueue.length = 0; traverseScopesLoop: do { // "traverse the scopes" loop if ((watchers = current.$$watchers)) { // process our watches watchers.$$digestWatchIndex = watchers.length; while (watchers.$$digestWatchIndex--) { try { watch = watchers[watchers.$$digestWatchIndex]; // Most common watches are on primitives, in which case we can short // circuit it with === operator, only when === fails do we use .equals if (watch) { get = watch.get; if ((value = get(current)) !== (last = watch.last) && !(watch.eq ? equals(value, last) : (isNumberNaN(value) && isNumberNaN(last)))) { dirty = true; lastDirtyWatch = watch; watch.last = watch.eq ? copy(value, null) : value; fn = watch.fn; fn(value, ((last === initWatchVal) ? value : last), current); if (ttl < 5) { logIdx = 4 - ttl; if (!watchLog[logIdx]) watchLog[logIdx] = []; watchLog[logIdx].push({ msg: isFunction(watch.exp) ? 'fn: ' + (watch.exp.name || watch.exp.toString()) : watch.exp, newVal: value, oldVal: last }); } } else if (watch === lastDirtyWatch) { // If the most recently dirty watcher is now clean, short circuit since the remaining watchers // have already been tested. dirty = false; break traverseScopesLoop; } } } catch (e) { $exceptionHandler(e); } } } // Insanity Warning: scope depth-first traversal // yes, this code is a bit crazy, but it works and we have tests to prove it! // this piece should be kept in sync with the traversal in $broadcast if (!(next = ((current.$$watchersCount && current.$$childHead) || (current !== target && current.$$nextSibling)))) { while (current !== target && !(next = current.$$nextSibling)) { current = current.$parent; } } } while ((current = next)); // `break traverseScopesLoop;` takes us to here if ((dirty || asyncQueue.length) && !(ttl--)) { clearPhase(); throw $rootScopeMinErr('infdig', '{0} $digest() iterations reached. Aborting!\n' + 'Watchers fired in the last 5 iterations: {1}', TTL, watchLog); } } while (dirty || asyncQueue.length); clearPhase(); // postDigestQueuePosition isn't local here because this loop can be reentered recursively. while (postDigestQueuePosition < postDigestQueue.length) { try { postDigestQueue[postDigestQueuePosition++](); } catch (e) { $exceptionHandler(e); } } postDigestQueue.length = postDigestQueuePosition = 0; // Check for changes to browser url that happened during the $digest // (for which no event is fired; e.g. via `history.pushState()`) $browser.$$checkUrlChange(); }, /** * @ngdoc event * @name $rootScope.Scope#$destroy * @eventType broadcast on scope being destroyed * * @description * Broadcasted when a scope and its children are being destroyed. * * Note that, in AngularJS, there is also a `$destroy` jQuery event, which can be used to * clean up DOM bindings before an element is removed from the DOM. */ /** * @ngdoc method * @name $rootScope.Scope#$destroy * @kind function * * @description * Removes the current scope (and all of its children) from the parent scope. Removal implies * that calls to {@link ng.$rootScope.Scope#$digest $digest()} will no longer * propagate to the current scope and its children. Removal also implies that the current * scope is eligible for garbage collection. * * The `$destroy()` is usually used by directives such as * {@link ng.directive:ngRepeat ngRepeat} for managing the * unrolling of the loop. * * Just before a scope is destroyed, a `$destroy` event is broadcasted on this scope. * Application code can register a `$destroy` event handler that will give it a chance to * perform any necessary cleanup. * * Note that, in AngularJS, there is also a `$destroy` jQuery event, which can be used to * clean up DOM bindings before an element is removed from the DOM. */ $destroy: function() { // We can't destroy a scope that has been already destroyed. if (this.$$destroyed) return; var parent = this.$parent; this.$broadcast('$destroy'); this.$$destroyed = true; if (this === $rootScope) { //Remove handlers attached to window when $rootScope is removed $browser.$$applicationDestroyed(); } incrementWatchersCount(this, -this.$$watchersCount); for (var eventName in this.$$listenerCount) { decrementListenerCount(this, this.$$listenerCount[eventName], eventName); } // sever all the references to parent scopes (after this cleanup, the current scope should // not be retained by any of our references and should be eligible for garbage collection) if (parent && parent.$$childHead === this) parent.$$childHead = this.$$nextSibling; if (parent && parent.$$childTail === this) parent.$$childTail = this.$$prevSibling; if (this.$$prevSibling) this.$$prevSibling.$$nextSibling = this.$$nextSibling; if (this.$$nextSibling) this.$$nextSibling.$$prevSibling = this.$$prevSibling; // Disable listeners, watchers and apply/digest methods this.$destroy = this.$digest = this.$apply = this.$evalAsync = this.$applyAsync = noop; this.$on = this.$watch = this.$watchGroup = function() { return noop; }; this.$$listeners = {}; // Disconnect the next sibling to prevent `cleanUpScope` destroying those too this.$$nextSibling = null; cleanUpScope(this); }, /** * @ngdoc method * @name $rootScope.Scope#$eval * @kind function * * @description * Executes the `expression` on the current scope and returns the result. Any exceptions in * the expression are propagated (uncaught). This is useful when evaluating AngularJS * expressions. * * # Example * ```js var scope = ng.$rootScope.Scope(); scope.a = 1; scope.b = 2; expect(scope.$eval('a+b')).toEqual(3); expect(scope.$eval(function(scope){ return scope.a + scope.b; })).toEqual(3); * ``` * * @param {(string|function())=} expression An AngularJS expression to be executed. * * - `string`: execute using the rules as defined in {@link guide/expression expression}. * - `function(scope)`: execute the function with the current `scope` parameter. * * @param {(object)=} locals Local variables object, useful for overriding values in scope. * @returns {*} The result of evaluating the expression. */ $eval: function(expr, locals) { return $parse(expr)(this, locals); }, /** * @ngdoc method * @name $rootScope.Scope#$evalAsync * @kind function * * @description * Executes the expression on the current scope at a later point in time. * * The `$evalAsync` makes no guarantees as to when the `expression` will be executed, only * that: * * - it will execute after the function that scheduled the evaluation (preferably before DOM * rendering). * - at least one {@link ng.$rootScope.Scope#$digest $digest cycle} will be performed after * `expression` execution. * * Any exceptions from the execution of the expression are forwarded to the * {@link ng.$exceptionHandler $exceptionHandler} service. * * __Note:__ if this function is called outside of a `$digest` cycle, a new `$digest` cycle * will be scheduled. However, it is encouraged to always call code that changes the model * from within an `$apply` call. That includes code evaluated via `$evalAsync`. * * @param {(string|function())=} expression An AngularJS expression to be executed. * * - `string`: execute using the rules as defined in {@link guide/expression expression}. * - `function(scope)`: execute the function with the current `scope` parameter. * * @param {(object)=} locals Local variables object, useful for overriding values in scope. */ $evalAsync: function(expr, locals) { // if we are outside of an $digest loop and this is the first time we are scheduling async // task also schedule async auto-flush if (!$rootScope.$$phase && !asyncQueue.length) { $browser.defer(function() { if (asyncQueue.length) { $rootScope.$digest(); } }); } asyncQueue.push({scope: this, fn: $parse(expr), locals: locals}); }, $$postDigest: function(fn) { postDigestQueue.push(fn); }, /** * @ngdoc method * @name $rootScope.Scope#$apply * @kind function * * @description * `$apply()` is used to execute an expression in AngularJS from outside of the AngularJS * framework. (For example from browser DOM events, setTimeout, XHR or third party libraries). * Because we are calling into the AngularJS framework we need to perform proper scope life * cycle of {@link ng.$exceptionHandler exception handling}, * {@link ng.$rootScope.Scope#$digest executing watches}. * * ## Life cycle * * # Pseudo-Code of `$apply()` * ```js function $apply(expr) { try { return $eval(expr); } catch (e) { $exceptionHandler(e); } finally { $root.$digest(); } } * ``` * * * Scope's `$apply()` method transitions through the following stages: * * 1. The {@link guide/expression expression} is executed using the * {@link ng.$rootScope.Scope#$eval $eval()} method. * 2. Any exceptions from the execution of the expression are forwarded to the * {@link ng.$exceptionHandler $exceptionHandler} service. * 3. The {@link ng.$rootScope.Scope#$watch watch} listeners are fired immediately after the * expression was executed using the {@link ng.$rootScope.Scope#$digest $digest()} method. * * * @param {(string|function())=} exp An AngularJS expression to be executed. * * - `string`: execute using the rules as defined in {@link guide/expression expression}. * - `function(scope)`: execute the function with current `scope` parameter. * * @returns {*} The result of evaluating the expression. */ $apply: function(expr) { try { beginPhase('$apply'); try { return this.$eval(expr); } finally { clearPhase(); } } catch (e) { $exceptionHandler(e); } finally { try { $rootScope.$digest(); } catch (e) { $exceptionHandler(e); // eslint-disable-next-line no-unsafe-finally throw e; } } }, /** * @ngdoc method * @name $rootScope.Scope#$applyAsync * @kind function * * @description * Schedule the invocation of $apply to occur at a later time. The actual time difference * varies across browsers, but is typically around ~10 milliseconds. * * This can be used to queue up multiple expressions which need to be evaluated in the same * digest. * * @param {(string|function())=} exp An AngularJS expression to be executed. * * - `string`: execute using the rules as defined in {@link guide/expression expression}. * - `function(scope)`: execute the function with current `scope` parameter. */ $applyAsync: function(expr) { var scope = this; if (expr) { applyAsyncQueue.push($applyAsyncExpression); } expr = $parse(expr); scheduleApplyAsync(); function $applyAsyncExpression() { scope.$eval(expr); } }, /** * @ngdoc method * @name $rootScope.Scope#$on * @kind function * * @description * Listens on events of a given type. See {@link ng.$rootScope.Scope#$emit $emit} for * discussion of event life cycle. * * The event listener function format is: `function(event, args...)`. The `event` object * passed into the listener has the following attributes: * * - `targetScope` - `{Scope}`: the scope on which the event was `$emit`-ed or * `$broadcast`-ed. * - `currentScope` - `{Scope}`: the scope that is currently handling the event. Once the * event propagates through the scope hierarchy, this property is set to null. * - `name` - `{string}`: name of the event. * - `stopPropagation` - `{function=}`: calling `stopPropagation` function will cancel * further event propagation (available only for events that were `$emit`-ed). * - `preventDefault` - `{function}`: calling `preventDefault` sets `defaultPrevented` flag * to true. * - `defaultPrevented` - `{boolean}`: true if `preventDefault` was called. * * @param {string} name Event name to listen on. * @param {function(event, ...args)} listener Function to call when the event is emitted. * @returns {function()} Returns a deregistration function for this listener. */ $on: function(name, listener) { var namedListeners = this.$$listeners[name]; if (!namedListeners) { this.$$listeners[name] = namedListeners = []; } namedListeners.push(listener); var current = this; do { if (!current.$$listenerCount[name]) { current.$$listenerCount[name] = 0; } current.$$listenerCount[name]++; } while ((current = current.$parent)); var self = this; return function() { var indexOfListener = namedListeners.indexOf(listener); if (indexOfListener !== -1) { namedListeners[indexOfListener] = null; decrementListenerCount(self, 1, name); } }; }, /** * @ngdoc method * @name $rootScope.Scope#$emit * @kind function * * @description * Dispatches an event `name` upwards through the scope hierarchy notifying the * registered {@link ng.$rootScope.Scope#$on} listeners. * * The event life cycle starts at the scope on which `$emit` was called. All * {@link ng.$rootScope.Scope#$on listeners} listening for `name` event on this scope get * notified. Afterwards, the event traverses upwards toward the root scope and calls all * registered listeners along the way. The event will stop propagating if one of the listeners * cancels it. * * Any exception emitted from the {@link ng.$rootScope.Scope#$on listeners} will be passed * onto the {@link ng.$exceptionHandler $exceptionHandler} service. * * @param {string} name Event name to emit. * @param {...*} args Optional one or more arguments which will be passed onto the event listeners. * @return {Object} Event object (see {@link ng.$rootScope.Scope#$on}). */ $emit: function(name, args) { var empty = [], namedListeners, scope = this, stopPropagation = false, event = { name: name, targetScope: scope, stopPropagation: function() {stopPropagation = true;}, preventDefault: function() { event.defaultPrevented = true; }, defaultPrevented: false }, listenerArgs = concat([event], arguments, 1), i, length; do { namedListeners = scope.$$listeners[name] || empty; event.currentScope = scope; for (i = 0, length = namedListeners.length; i < length; i++) { // if listeners were deregistered, defragment the array if (!namedListeners[i]) { namedListeners.splice(i, 1); i--; length--; continue; } try { //allow all listeners attached to the current scope to run namedListeners[i].apply(null, listenerArgs); } catch (e) { $exceptionHandler(e); } } //if any listener on the current scope stops propagation, prevent bubbling if (stopPropagation) { event.currentScope = null; return event; } //traverse upwards scope = scope.$parent; } while (scope); event.currentScope = null; return event; }, /** * @ngdoc method * @name $rootScope.Scope#$broadcast * @kind function * * @description * Dispatches an event `name` downwards to all child scopes (and their children) notifying the * registered {@link ng.$rootScope.Scope#$on} listeners. * * The event life cycle starts at the scope on which `$broadcast` was called. All * {@link ng.$rootScope.Scope#$on listeners} listening for `name` event on this scope get * notified. Afterwards, the event propagates to all direct and indirect scopes of the current * scope and calls all registered listeners along the way. The event cannot be canceled. * * Any exception emitted from the {@link ng.$rootScope.Scope#$on listeners} will be passed * onto the {@link ng.$exceptionHandler $exceptionHandler} service. * * @param {string} name Event name to broadcast. * @param {...*} args Optional one or more arguments which will be passed onto the event listeners. * @return {Object} Event object, see {@link ng.$rootScope.Scope#$on} */ $broadcast: function(name, args) { var target = this, current = target, next = target, event = { name: name, targetScope: target, preventDefault: function() { event.defaultPrevented = true; }, defaultPrevented: false }; if (!target.$$listenerCount[name]) return event; var listenerArgs = concat([event], arguments, 1), listeners, i, length; //down while you can, then up and next sibling or up and next sibling until back at root while ((current = next)) { event.currentScope = current; listeners = current.$$listeners[name] || []; for (i = 0, length = listeners.length; i < length; i++) { // if listeners were deregistered, defragment the array if (!listeners[i]) { listeners.splice(i, 1); i--; length--; continue; } try { listeners[i].apply(null, listenerArgs); } catch (e) { $exceptionHandler(e); } } // Insanity Warning: scope depth-first traversal // yes, this code is a bit crazy, but it works and we have tests to prove it! // this piece should be kept in sync with the traversal in $digest // (though it differs due to having the extra check for $$listenerCount) if (!(next = ((current.$$listenerCount[name] && current.$$childHead) || (current !== target && current.$$nextSibling)))) { while (current !== target && !(next = current.$$nextSibling)) { current = current.$parent; } } } event.currentScope = null; return event; } }; var $rootScope = new Scope(); //The internal queues. Expose them on the $rootScope for debugging/testing purposes. var asyncQueue = $rootScope.$$asyncQueue = []; var postDigestQueue = $rootScope.$$postDigestQueue = []; var applyAsyncQueue = $rootScope.$$applyAsyncQueue = []; var postDigestQueuePosition = 0; return $rootScope; function beginPhase(phase) { if ($rootScope.$$phase) { throw $rootScopeMinErr('inprog', '{0} already in progress', $rootScope.$$phase); } $rootScope.$$phase = phase; } function clearPhase() { $rootScope.$$phase = null; } function incrementWatchersCount(current, count) { do { current.$$watchersCount += count; } while ((current = current.$parent)); } function decrementListenerCount(current, count, name) { do { current.$$listenerCount[name] -= count; if (current.$$listenerCount[name] === 0) { delete current.$$listenerCount[name]; } } while ((current = current.$parent)); } /** * function used as an initial value for watchers. * because it's unique we can easily tell it apart from other values */ function initWatchVal() {} function flushApplyAsync() { while (applyAsyncQueue.length) { try { applyAsyncQueue.shift()(); } catch (e) { $exceptionHandler(e); } } applyAsyncId = null; } function scheduleApplyAsync() { if (applyAsyncId === null) { applyAsyncId = $browser.defer(function() { $rootScope.$apply(flushApplyAsync); }); } } }]; }