feat(zone): add "on event done" zone hook

modules/angular2/src/core/application.ts

@@ -146,7 +146,7 @@ function _createNgZone(givenReporter: Function): NgZone {
   var reporter = isPresent(givenReporter) ? givenReporter : defaultErrorReporter;
 
   var zone = new NgZone({enableLongStackTrace: assertionsEnabled()});
-  zone.initCallbacks({onErrorHandler: reporter});
+  zone.overrideOnErrorHandler(reporter);
   return zone;
 }
 

modules/angular2/src/core/life_cycle/life_cycle.ts

@@ -57,7 +57,8 @@ export class LifeCycle {
       this._changeDetector = changeDetector;
     }
 
-    zone.initCallbacks({onErrorHandler: this._errorHandler, onTurnDone: () => this.tick()});
+    zone.overrideOnErrorHandler(this._errorHandler);
+    zone.overrideOnTurnDone(() => this.tick());
   }
 
   /**

modules/angular2/src/core/zone/ng_zone.dart

@@ -3,6 +3,9 @@ library angular.zone;
 import 'dart:async';
 import 'package:stack_trace/stack_trace.dart' show Chain;
 
+typedef void ZeroArgFunction();
+typedef void ErrorHandlingFn(error, stackTrace);
+
 /**
  * A `Zone` wrapper that lets you schedule tasks after its private microtask queue is exhausted but
  * before the next "VM turn", i.e. event loop iteration.
@@ -19,9 +22,10 @@ import 'package:stack_trace/stack_trace.dart' show Chain;
  * instantiated. The default `onTurnDone` runs the Angular change detection.
  */
 class NgZone {
-  Function _onTurnStart;
+  ZeroArgFunction _onTurnStart;
-  Function _onTurnDone;
+  ZeroArgFunction _onTurnDone;
-  Function _onErrorHandler;
+  ZeroArgFunction _onEventDone;
+  ErrorHandlingFn _onErrorHandler;
 
   // Code executed in _mountZone does not trigger the onTurnDone.
   Zone _mountZone;
@@ -65,21 +69,40 @@ class NgZone {
   }
 
   /**
-   * Initializes the zone hooks.
+   * Sets the zone hook that is called just before Angular event turn starts.
-   *
+   * It is called once per browser event.
-   * The given error handler should re-throw the passed exception. Otherwise, exceptions will not
-   * propagate outside of the [NgZone] and can alter the application execution flow.
-   * Not re-throwing could be used to help testing the code or advanced use cases.
-   *
-   * @param {Function} onTurnStart called before code executes in the inner zone for each VM turn
-   * @param {Function} onTurnDone called at the end of a VM turn if code has executed in the inner zone
-   * @param {Function} onErrorHandler called when an exception is thrown by a macro or micro task
    */
-  void initCallbacks(
+  void overrideOnTurnStart(ZeroArgFunction onTurnStartFn) {
-      {Function onTurnStart, Function onTurnDone, Function onErrorHandler}) {
+    this._onTurnStart = onTurnStartFn;
-    _onTurnStart = onTurnStart;
+  }
-    _onTurnDone = onTurnDone;
+
-    _onErrorHandler = onErrorHandler;
+  /**
+   * Sets the zone hook that is called immediately after Angular processes
+   * all pending microtasks.
+   */
+  void overrideOnTurnDone(ZeroArgFunction onTurnDoneFn) {
+    this._onTurnDone = onTurnDoneFn;
+  }
+
+  /**
+   * Sets the zone hook that is called immediately after the last turn in the
+   * current event completes. At this point Angular will no longer attempt to
+   * sync the UI. Any changes to the data model will not be reflected in the
+   * DOM. {@link onEventDoneFn} is executed outside Angular zone.
+   *
+   * This hook is useful for validating application state (e.g. in a test).
+   */
+  void overrideOnEventDone(ZeroArgFunction onEventDoneFn) {
+    this._onEventDone = onEventDoneFn;
+  }
+
+  /**
+   * Sets the zone hook that is called when an error is uncaught in the
+   * Angular zone. The first argument is the error. The second argument is
+   * the stack trace.
+   */
+  void overrideOnErrorHandler(ErrorHandlingFn errorHandlingFn) {
+    this._onErrorHandler = errorHandlingFn;
   }
 
   /**
@@ -151,6 +174,10 @@ class NgZone {
           try {
             _inVmTurnDone = true;
             parent.run(_innerZone, _onTurnDone);  
+
+            if (_pendingMicrotasks == 0 && _onEventDone != null) {
+              runOutsideAngular(_onEventDone);
+            }
           } finally {
             _inVmTurnDone = false;
             _hasExecutedCodeInInnerZone = false;

modules/angular2/src/core/zone/ng_zone.ts

@@ -23,6 +23,7 @@ export class NgZone {
 
   _onTurnStart: () => void;
   _onTurnDone: () => void;
+  _onEventDone: () => void;
   _onErrorHandler: (error, stack) => void;
 
   // Number of microtasks pending from _innerZone (& descendants)
@@ -53,6 +54,7 @@ export class NgZone {
   constructor({enableLongStackTrace}) {
     this._onTurnStart = null;
     this._onTurnDone = null;
+    this._onEventDone = null;
     this._onErrorHandler = null;
 
     this._pendingMicrotasks = 0;
@@ -70,22 +72,40 @@ export class NgZone {
   }
 
   /**
-   * Initializes the zone hooks.
+   * Sets the zone hook that is called just before Angular event turn starts.
-   *
+   * It is called once per browser event.
-   * @param {() => void} onTurnStart called before code executes in the inner zone for each VM turn
-   * @param {() => void} onTurnDone called at the end of a VM turn if code has executed in the inner
-   * zone
-   * @param {(error, stack) => void} onErrorHandler called when an exception is thrown by a macro or
-   * micro task
    */
-  initCallbacks({onTurnStart, onTurnDone, onErrorHandler}: {
+  overrideOnTurnStart(onTurnStartFn: Function): void {
-    onTurnStart?: /*() => void*/ Function,
+    this._onTurnStart = normalizeBlank(onTurnStartFn);
-    onTurnDone?: /*() => void*/ Function,
+  }
-    onErrorHandler?: /*(error, stack) => void*/ Function
+
-  } = {}) {
+  /**
-    this._onTurnStart = normalizeBlank(onTurnStart);
+   * Sets the zone hook that is called immediately after Angular processes
-    this._onTurnDone = normalizeBlank(onTurnDone);
+   * all pending microtasks.
-    this._onErrorHandler = normalizeBlank(onErrorHandler);
+   */
+  overrideOnTurnDone(onTurnDoneFn: Function): void {
+    this._onTurnDone = normalizeBlank(onTurnDoneFn);
+  }
+
+  /**
+   * Sets the zone hook that is called immediately after the last turn in the
+   * current event completes. At this point Angular will no longer attempt to
+   * sync the UI. Any changes to the data model will not be reflected in the
+   * DOM. {@link onEventDoneFn} is executed outside Angular zone.
+   *
+   * This hook is useful for validating application state (e.g. in a test).
+   */
+  overrideOnEventDone(onEventDoneFn: Function): void {
+    this._onEventDone = normalizeBlank(onEventDoneFn);
+  }
+
+  /**
+   * Sets the zone hook that is called when an error is uncaught in the
+   * Angular zone. The first argument is the error. The second argument is
+   * the stack trace.
+   */
+  overrideOnErrorHandler(errorHandlingFn: Function): void {
+    this._onErrorHandler = normalizeBlank(errorHandlingFn);
   }
 
   /**
@@ -172,6 +192,9 @@ export class NgZone {
                     try {
                       this._inVmTurnDone = true;
                       parentRun.call(ngZone._innerZone, ngZone._onTurnDone);
+                      if (ngZone._pendingMicrotasks === 0 && isPresent(ngZone._onEventDone)) {
+                        ngZone.runOutsideAngular(ngZone._onEventDone);
+                      }
                     } finally {
                       this._inVmTurnDone = false;
                       ngZone._hasExecutedCodeInInnerZone = false;

modules/angular2/test/core/zone/ng_zone_spec.ts

@@ -46,7 +46,8 @@ export function main() {
 
     function createZone(enableLongStackTrace) {
       var zone = new NgZone({enableLongStackTrace: enableLongStackTrace});
-      zone.initCallbacks({onTurnStart: _log.fn('onTurnStart'), onTurnDone: _log.fn('onTurnDone')});
+      zone.overrideOnTurnStart(_log.fn('onTurnStart'));
+      zone.overrideOnTurnDone(_log.fn('onTurnDone'));
       return zone;
     }
 
@@ -63,7 +64,7 @@ export function main() {
 
       it('should produce long stack traces', inject([AsyncTestCompleter], (async) => {
            macroTask(() => {
-             _zone.initCallbacks({onErrorHandler: logError});
+             _zone.overrideOnErrorHandler(logError);
              var c = PromiseWrapper.completer();
 
              _zone.run(() => {
@@ -86,7 +87,7 @@ export function main() {
       it('should produce long stack traces (when using microtasks)',
          inject([AsyncTestCompleter], (async) => {
            macroTask(() => {
-             _zone.initCallbacks({onErrorHandler: logError});
+             _zone.overrideOnErrorHandler(logError);
              var c = PromiseWrapper.completer();
 
              _zone.run(() => {
@@ -114,7 +115,7 @@ export function main() {
 
       it('should disable long stack traces', inject([AsyncTestCompleter], (async) => {
            macroTask(() => {
-             _zone.initCallbacks({onErrorHandler: logError});
+             _zone.overrideOnErrorHandler(logError);
              var c = PromiseWrapper.completer();
 
              _zone.run(() => {
@@ -160,6 +161,77 @@ function commonTests() {
          });
        }));
 
+    it('should call onEventDone once at the end of event', inject([AsyncTestCompleter], (async) => {
+         // The test is set up in a way that causes the zone loop to run onTurnDone twice
+         // then verified that onEventDone is only called once at the end
+         _zone.overrideOnTurnStart(null);
+         _zone.overrideOnEventDone(() => { _log.add('onEventDone'); });
+
+         var times = 0;
+         _zone.overrideOnTurnDone(() => {
+           times++;
+           _log.add(`onTurnDone ${times}`);
+           if (times < 2) {
+             // Scheduling a microtask causes a second digest
+             microTask(() => {});
+           }
+         });
+
+         macroTask(() => { _zone.run(_log.fn('run')); });
+
+         macroTask(() => {
+           expect(_log.result()).toEqual('run; onTurnDone 1; onTurnDone 2; onEventDone');
+           async.done();
+         });
+       }));
+
+    it('should not allow onEventDone to cause further digests',
+       inject([AsyncTestCompleter], (async) => {
+         _zone.overrideOnTurnStart(null);
+
+         var eventDone = false;
+         _zone.overrideOnEventDone(() => {
+           if (eventDone) throw 'Should not call this more than once';
+           _log.add('onEventDone');
+           // If not implemented correctly, this microtask will cause another digest,
+           // which is not what we want.
+           microTask(() => {});
+           eventDone = true;
+         });
+
+         _zone.overrideOnTurnDone(() => { _log.add('onTurnDone'); });
+
+         macroTask(() => { _zone.run(_log.fn('run')); });
+
+         macroTask(() => {
+           expect(_log.result()).toEqual('run; onTurnDone; onEventDone');
+           async.done();
+         });
+       }));
+
+    it('should run async tasks scheduled inside onEventDone outside Angular zone',
+       inject([AsyncTestCompleter], (async) => {
+         _zone.overrideOnTurnStart(null);
+
+         _zone.overrideOnEventDone(() => {
+           _log.add('onEventDone');
+           // If not implemented correctly, this time will cause another digest,
+           // which is not what we want.
+           TimerWrapper.setTimeout(() => { _log.add('asyncTask'); }, 5);
+         });
+
+         _zone.overrideOnTurnDone(() => { _log.add('onTurnDone'); });
+
+         macroTask(() => { _zone.run(_log.fn('run')); });
+
+         macroTask(() => {
+           TimerWrapper.setTimeout(() => {
+             expect(_log.result()).toEqual('run; onTurnDone; onEventDone; asyncTask');
+             async.done();
+           }, 10);
+         });
+       }));
+
     it('should call onTurnStart once before a turn and onTurnDone once after the turn',
        inject([AsyncTestCompleter], (async) => {
 
@@ -201,12 +273,11 @@ function commonTests() {
 
     it('should not run onTurnStart and onTurnDone for nested Zone.run invoked from onTurnDone',
        inject([AsyncTestCompleter], (async) => {
-         _zone.initCallbacks({
+         _zone.overrideOnTurnStart(null);
-           onTurnDone: () => {
+         _zone.overrideOnTurnDone(() => {
            _log.add('onTurnDone:started');
            _zone.run(() => _log.add('nested run'));
            _log.add('onTurnDone:finished');
-           }
          });
 
          macroTask(() => { _zone.run(() => { _log.add('start run'); }); });
@@ -306,9 +377,8 @@ function commonTests() {
            'onTurnDone after executing the task',
        inject([AsyncTestCompleter], (async) => {
          var ran = false;
-         _zone.initCallbacks({
+         _zone.overrideOnTurnStart(_log.fn('onTurnStart'));
-           onTurnStart: _log.fn('onTurnStart'),
+         _zone.overrideOnTurnDone(() => {
-           onTurnDone: () => {
            _log.add('onTurnDone(begin)');
            if (!ran) {
              microTask(() => {
@@ -318,7 +388,6 @@ function commonTests() {
            }
 
            _log.add('onTurnDone(end)');
-           }
          });
 
          macroTask(() => { _zone.run(_log.fn('run')); });
@@ -338,9 +407,8 @@ function commonTests() {
            'a scheduleMicrotask in run',
        inject([AsyncTestCompleter], (async) => {
          var ran = false;
-         _zone.initCallbacks({
+         _zone.overrideOnTurnStart(_log.fn('onTurnStart'));
-           onTurnStart: _log.fn('onTurnStart'),
+         _zone.overrideOnTurnDone(() => {
-           onTurnDone: () => {
            _log.add('onTurnDone(begin)');
            if (!ran) {
              _log.add('onTurnDone(scheduleMicrotask)');
@@ -350,7 +418,6 @@ function commonTests() {
              });
            }
            _log.add('onTurnDone(end)');
-           }
          });
 
          macroTask(() => {
@@ -376,8 +443,7 @@ function commonTests() {
          var donePromiseRan = false;
          var startPromiseRan = false;
 
-         _zone.initCallbacks({
+         _zone.overrideOnTurnStart(() => {
-           onTurnStart: () => {
            _log.add('onTurnStart(begin)');
            if (!startPromiseRan) {
              _log.add('onTurnStart(schedulePromise)');
@@ -385,8 +451,8 @@ function commonTests() {
              startPromiseRan = true;
            }
            _log.add('onTurnStart(end)');
-           },
+         });
-           onTurnDone: () => {
+         _zone.overrideOnTurnDone(() => {
            _log.add('onTurnDone(begin)');
            if (!donePromiseRan) {
              _log.add('onTurnDone(schedulePromise)');
@@ -394,7 +460,6 @@ function commonTests() {
              donePromiseRan = true;
            }
            _log.add('onTurnDone(end)');
-           }
          });
 
          macroTask(() => {
@@ -507,7 +572,7 @@ function commonTests() {
     it('should call the on error callback when it is defined',
        inject([AsyncTestCompleter], (async) => {
          macroTask(() => {
-           _zone.initCallbacks({onErrorHandler: logError});
+           _zone.overrideOnErrorHandler(logError);
 
            var exception = new BaseException('sync');
 
@@ -520,7 +585,7 @@ function commonTests() {
        }));
 
     it('should call onError for errors from microtasks', inject([AsyncTestCompleter], (async) => {
-         _zone.initCallbacks({onErrorHandler: logError});
+         _zone.overrideOnErrorHandler(logError);
 
          var exception = new BaseException('async');
 
@@ -537,7 +602,8 @@ function commonTests() {
        inject([AsyncTestCompleter], (async) => {
          var exception = new BaseException('fromOnTurnDone');
 
-         _zone.initCallbacks({onErrorHandler: logError, onTurnDone: () => { throw exception; }});
+         _zone.overrideOnErrorHandler(logError);
+         _zone.overrideOnTurnDone(() => { throw exception; });
 
          macroTask(() => { _zone.run(() => {}); });
 
@@ -554,7 +620,8 @@ function commonTests() {
 
          var exception = new BaseException('fromOnTurnDone');
 
-         _zone.initCallbacks({onErrorHandler: logError, onTurnDone: () => { throw exception; }});
+         _zone.overrideOnErrorHandler(logError);
+         _zone.overrideOnTurnDone(() => { throw exception; });
 
          macroTask(() => { _zone.run(() => { microTask(() => { asyncRan = true; }); }); });