feat(fakeAsync): allow simulating the passage of time

modules/angular2/src/test_lib/fake_async.dart

@@ -0,0 +1,74 @@
+library test_lib.fake_async;
+
+import 'dart:async' show runZoned, ZoneSpecification;
+import 'package:quiver/testing/async.dart' as quiver;
+import 'package:angular2/src/facade/lang.dart' show BaseException;
+
+const _u = const Object();
+
+quiver.FakeAsync _fakeAsync = null;
+
+/**
+ * Wraps the [fn] to be executed in the fakeAsync zone:
+ * - microtasks are manually executed by calling [flushMicrotasks],
+ * - timers are synchronous, [tick] simulates the asynchronous passage of time.
+ *
+ * If there are any pending timers at the end of the function, an exception
+ * will be thrown.
+ *
+ * Returns a `Function` that wraps [fn].
+ */
+Function fakeAsync(Function fn) {
+  if (_fakeAsync != null) {
+    throw 'fakeAsync() calls can not be nested';
+  }
+
+  return ([a0 = _u, a1 = _u, a2 = _u, a3 = _u, a4 = _u, a5 = _u, a6 = _u,
+           a7 = _u, a8 = _u, a9 = _u]) {
+    // runZoned() to install a custom exception handler that re-throws
+    return runZoned(() {
+      new quiver.FakeAsync().run((quiver.FakeAsync async) {
+        try {
+          _fakeAsync = async;
+          List args = [a0, a1, a2, a3, a4, a5, a6, a7, a8, a9]
+              .takeWhile((a) => a != _u).toList();
+          return Function.apply(fn , args);
+        } finally {
+          _fakeAsync = null;
+        }
+      });
+    },
+    zoneSpecification: new ZoneSpecification(
+        handleUncaughtError: (self, parent, zone, error, stackTrace)
+            => throw error
+    ));
+  };
+}
+
+/**
+ * Simulates the asynchronous passage of [millis] milliseconds for the timers
+ * in the fakeAsync zone.
+ *
+ * The microtasks queue is drained at the very start of this function and after
+ * any timer callback has been executed.
+ */
+void tick([int millis = 0]) {
+  _assertInFakeAsyncZone();
+  var duration = new Duration(milliseconds: millis);
+  _fakeAsync.elapse(duration);
+}
+
+/**
+ * Flush any pending microtasks.
+ */
+void flushMicrotasks() {
+  _assertInFakeAsyncZone();
+  _fakeAsync.flushMicrotasks();
+}
+
+void _assertInFakeAsyncZone() {
+  if (_fakeAsync == null) {
+    throw new BaseException('The code should be running in the fakeAsync zone '
+        'to call this function');
+  }
+}

modules/angular2/src/test_lib/fake_async.es6

@@ -0,0 +1,131 @@
+import {BaseException, global} from 'angular2/src/facade/lang';
+import {ListWrapper} from 'angular2/src/facade/collection';
+
+var _scheduler;
+var _microtasks:List<Function> = [];
+var _pendingPeriodicTimers: List<number> = [];
+var _pendingTimers: List<number> = [];
+var _error = null;
+
+/**
+ * Wraps a function to be executed in the fakeAsync zone:
+ * - microtasks are manually executed by calling `flushMicrotasks()`,
+ * - timers are synchronous, `tick()` simulates the asynchronous passage of time.
+ *
+ * If there are any pending timers at the end of the function, an exception will be thrown.
+ *
+ * @param fn
+ * @returns {Function} The function wrapped to be executed in the fakeAsync zone
+ */
+export function fakeAsync(fn: Function): Function {
+  // TODO(vicb) re-enable once the jasmine patch from zone.js is applied
+  //if (global.zone._inFakeAsyncZone) {
+  //  throw new Error('fakeAsync() calls can not be nested');
+  //}
+
+  var fakeAsyncZone = global.zone.fork({
+    setTimeout: _setTimeout,
+    clearTimeout: _clearTimeout,
+    setInterval: _setInterval,
+    clearInterval: _clearInterval,
+    scheduleMicrotask: _scheduleMicrotask,
+    _inFakeAsyncZone: true
+  });
+
+  return function(...args) {
+    _scheduler = global.jasmine.DelayedFunctionScheduler();
+    ListWrapper.clear(_microtasks);
+    ListWrapper.clear(_pendingPeriodicTimers);
+    ListWrapper.clear(_pendingTimers);
+
+    var res = fakeAsyncZone.run(() => {
+      var res = fn(...args);
+    });
+
+    if (_pendingPeriodicTimers.length > 0) {
+      throw new BaseException(`${_pendingPeriodicTimers.length} periodic timer(s) still in the queue.`);
+    }
+
+    if (_pendingTimers.length > 0) {
+      throw new BaseException(`${_pendingTimers.length} timer(s) still in the queue.`);
+    }
+
+    _scheduler = null;
+    ListWrapper.clear(_microtasks);
+
+    return res;
+  }
+}
+
+/**
+ * Simulates the asynchronous passage of time for the timers in the fakeAsync zone.
+ *
+ * The microtasks queue is drained at the very start of this function and after any timer callback has been executed.
+ *
+ * @param {number} millis Number of millisecond, defaults to 0
+ */
+export function tick(millis: number = 0): void {
+  _assertInFakeAsyncZone();
+  flushMicrotasks();
+  _scheduler.tick(millis);
+}
+
+/**
+ * Flush any pending microtasks.
+ */
+export function flushMicrotasks(): void {
+  _assertInFakeAsyncZone();
+  while (_microtasks.length > 0) {
+    var microtask = ListWrapper.removeAt(_microtasks, 0);
+    microtask();
+  }
+}
+
+function _setTimeout(fn: Function, delay: number, ...args): number {
+  var cb = _fnAndFlush(fn);
+  var id = _scheduler.scheduleFunction(cb, delay, args);
+  ListWrapper.push(_pendingTimers, id);
+  _scheduler.scheduleFunction(_dequeueTimer(id), delay);
+  return id;
+}
+
+function _clearTimeout(id: number) {
+  _dequeueTimer(id);
+  return _scheduler.removeFunctionWithId(id);
+}
+
+function _setInterval(fn: Function, interval: number, ...args) {
+  var cb = _fnAndFlush(fn);
+  var id = _scheduler.scheduleFunction(cb, interval, args, true);
+  _pendingPeriodicTimers.push(id);
+  return id;
+}
+
+function _clearInterval(id: number) {
+  ListWrapper.remove(_pendingPeriodicTimers, id);
+  return _scheduler.removeFunctionWithId(id);
+}
+
+function _fnAndFlush(fn: Function): void {
+  return () => {
+    fn.apply(global, arguments);
+    flushMicrotasks();
+  }
+}
+
+function _scheduleMicrotask(microtask: Function): void {
+  ListWrapper.push(_microtasks, microtask);
+}
+
+function _dequeueTimer(id: number): Function {
+  return function() {
+    ListWrapper.remove(_pendingTimers, id);
+  }
+}
+
+function _assertInFakeAsyncZone(): void {
+  if (!global.zone._inFakeAsyncZone) {
+    throw new Error('The code should be running in the fakeAsync zone to call this function');
+  }
+}
+

modules/angular2/src/test_lib/lang_utils.dart

@@ -1,3 +1,5 @@
+library test_lib.lang_utils;
+
 import 'dart:mirrors';
 
 Type getTypeOf(instance) => instance.runtimeType;