feat(fakeAsync): allow simulating the passage of time

modules/angular2/pubspec.yaml

@@ -17,8 +17,9 @@ dependencies:
   logging: '>=0.9.0 <0.11.0'
   source_span: '^1.0.0'
   stack_trace: '^1.1.1'
+  quiver: '^0.21.3+1'
 dev_dependencies:
-  guinness: "^0.1.17"
+  guinness: '^0.1.17'
 transformers:
 - angular2
 - $dart2js:

modules/angular2/src/facade/async.dart

@@ -25,8 +25,19 @@ class PromiseWrapper {
 
   static _Completer completer() => new _Completer(new Completer());
 
-  static void setTimeout(fn(), int millis) {
-    new Timer(new Duration(milliseconds: millis), fn);
+  // TODO(vic): create a TimerWrapper
+  static Timer setTimeout(fn(), int millis)
+      => new Timer(new Duration(milliseconds: millis), fn);
+  static void clearTimeout(Timer timer) {
+    timer.cancel();
+  }
+
+  static Timer setInterval(fn(), int millis) {
+    var interval = new Duration(milliseconds: millis);
+    return new Timer.periodic(interval, (Timer timer) { fn(); });
+  }
+  static void clearInterval(Timer timer) {
+    timer.cancel();
   }
 
   static bool isPromise(maybePromise) {

modules/angular2/src/facade/async.ts

@@ -45,7 +45,12 @@ export class PromiseWrapper {
     return {promise: p, resolve: resolve, reject: reject};
   }
 
-  static setTimeout(fn: Function, millis: int) { global.setTimeout(fn, millis); }
+  // TODO(vicb): create a TimerWrapper
+  static setTimeout(fn: Function, millis: int): int { return global.setTimeout(fn, millis); }
+  static clearTimeout(id: int): void { global.clearTimeout(id); }
+
+  static setInterval(fn: Function, millis: int): int { return global.setInterval(fn, millis); }
+  static clearInterval(id: int): void { global.clearInterval(id); }
 
   static isPromise(maybePromise): boolean { return maybePromise instanceof Promise; }
 }

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;

modules/angular2/test/test_lib/fake_async_spec.js

@@ -0,0 +1,290 @@
+import {
+    AsyncTestCompleter,
+    beforeEach,
+    ddescribe,
+    describe,
+    expect,
+    fakeAsync,
+    flushMicrotasks,
+    iit,
+    inject,
+    IS_DARTIUM,
+    it,
+    Log,
+    tick,
+    xit
+} from 'angular2/test_lib';
+import {PromiseWrapper} from 'angular2/src/facade/async';
+import {BaseException, global} from 'angular2/src/facade/lang';
+import {Parser} from 'angular2/change_detection';
+
+export function main() {
+  describe('fake async', () => {
+    it('should run synchronous code', () => {
+      var ran = false;
+      fakeAsync(() => {
+        ran = true;
+      })();
+
+      expect(ran).toEqual(true);
+    });
+
+    it('should pass arguments to the wrapped function', () => {
+      fakeAsync((foo, bar) => {
+        expect(foo).toEqual('foo');
+        expect(bar).toEqual('bar');
+      })('foo', 'bar');
+    });
+
+    it('should work with inject()', inject([Parser], fakeAsync((parser) => {
+      expect(parser).toBeAnInstanceOf(Parser);
+    })));
+
+    if (!IS_DARTIUM) {
+      it('should throw on nested calls', () => {
+        // TODO(vicb): re-enable once the jasmine patch from zone.js is applied
+        if (!IS_DARTIUM) return;
+        expect(() => {
+          fakeAsync(() => {
+            fakeAsync(() => null)();
+          })();
+        }).toThrowError('fakeAsync() calls can not be nested');
+      });
+    }
+
+    describe('Promise', () => {
+      it('should run asynchronous code', fakeAsync(() => {
+        var thenRan = false;
+        PromiseWrapper.resolve(null).then((_) => {
+          thenRan = true;
+        });
+
+        expect(thenRan).toEqual(false);
+
+        flushMicrotasks();
+        expect(thenRan).toEqual(true);
+      }));
+
+      it('should run chained thens', fakeAsync(() => {
+        var log = new Log();
+
+        PromiseWrapper
+            .resolve(null)
+            .then((_) => log.add(1))
+            .then((_) => log.add(2));
+
+        expect(log.result()).toEqual('');
+
+        flushMicrotasks();
+        expect(log.result()).toEqual('1; 2');
+      }));
+
+      it('should run Promise created in Promise', fakeAsync(() => {
+        var log = new Log();
+
+        PromiseWrapper
+            .resolve(null)
+            .then((_) => {
+              log.add(1);
+              PromiseWrapper.resolve(null).then((_) => log.add(2));
+            });
+
+        expect(log.result()).toEqual('');
+
+        flushMicrotasks();
+        expect(log.result()).toEqual('1; 2');
+      }));
+
+      // TODO(vicb): check why this doesn't work in JS - linked to open issues on GH ?
+      xit('should complain if the test throws an exception during async calls', () => {
+        expect(() => {
+          fakeAsync(() => {
+            PromiseWrapper.resolve(null).then((_) => {
+              throw new BaseException('async');
+            });
+            flushMicrotasks();
+          })();
+        }).toThrowError('async');
+      });
+
+      it('should complain if a test throws an exception', () => {
+        expect(() => {
+          fakeAsync(() => {
+            throw new BaseException('sync');
+          })();
+        }).toThrowError('sync');
+      });
+
+    });
+
+    describe('timers', () => {
+      it('should run queued zero duration timer on zero tick', fakeAsync(() => {
+        var ran = false;
+        PromiseWrapper.setTimeout(() => { ran = true }, 0);
+
+        expect(ran).toEqual(false);
+
+        tick();
+        expect(ran).toEqual(true);
+      }));
+
+
+      it('should run queued timer after sufficient clock ticks', fakeAsync(() => {
+        var ran = false;
+        PromiseWrapper.setTimeout(() => { ran = true; }, 10);
+
+        tick(6);
+        expect(ran).toEqual(false);
+
+        tick(6);
+        expect(ran).toEqual(true);
+      }));
+
+      it('should run queued timer only once', fakeAsync(() => {
+        var cycles = 0;
+        PromiseWrapper.setTimeout(() => { cycles++; }, 10);
+
+        tick(10);
+        expect(cycles).toEqual(1);
+
+        tick(10);
+        expect(cycles).toEqual(1);
+
+        tick(10);
+        expect(cycles).toEqual(1);
+      }));
+
+      it('should not run cancelled timer', fakeAsync(() => {
+        var ran = false;
+        var id = PromiseWrapper.setTimeout(() => { ran = true; }, 10);
+        PromiseWrapper.clearTimeout(id);
+
+        tick(10);
+        expect(ran).toEqual(false);
+      }));
+
+      it('should throw an error on dangling timers', () => {
+        // TODO(vicb): https://github.com/google/quiver-dart/issues/248
+        if (IS_DARTIUM) return;
+        expect(() => {
+          fakeAsync(() => {
+            PromiseWrapper.setTimeout(() => { }, 10);
+          })();
+        }).toThrowError('1 timer(s) still in the queue.');
+      });
+
+      it('should throw an error on dangling periodic timers', () => {
+        // TODO(vicb): https://github.com/google/quiver-dart/issues/248
+        if (IS_DARTIUM) return;
+        expect(() => {
+          fakeAsync(() => {
+            PromiseWrapper.setInterval(() => { }, 10);
+          })();
+        }).toThrowError('1 periodic timer(s) still in the queue.');
+      });
+
+      it('should run periodic timers', fakeAsync(() => {
+        var cycles = 0;
+        var id = PromiseWrapper.setInterval(() => { cycles++; }, 10);
+
+        tick(10);
+        expect(cycles).toEqual(1);
+
+        tick(10);
+        expect(cycles).toEqual(2);
+
+        tick(10);
+        expect(cycles).toEqual(3);
+
+        PromiseWrapper.clearInterval(id);
+      }));
+
+      it('should not run cancelled periodic timer', fakeAsync(() => {
+        var ran = false;
+        var id = PromiseWrapper.setInterval(() => { ran = true; }, 10);
+        PromiseWrapper.clearInterval(id);
+
+        tick(10);
+        expect(ran).toEqual(false);
+      }));
+
+      it('should be able to cancel periodic timers from a callback', fakeAsync(() => {
+        if (global != null && global.jasmine) {
+          // TODO(vicb): remove this when we switch to jasmine 2.3.3+
+          // see https://github.com/jasmine/jasmine/commit/51462f369b376615bc9d761dcaa5d822ea1ff8ee
+          return;
+        }
+
+        var cycles = 0;
+        var id;
+
+        id = PromiseWrapper.setInterval(() => {
+          cycles++;
+          PromiseWrapper.clearInterval(id);
+        }, 10);
+
+        tick(10);
+        expect(cycles).toEqual(1);
+
+        tick(10);
+        expect(cycles).toEqual(1);
+      }));
+
+      it('should process microtasks before timers', fakeAsync(() => {
+        var log = new Log();
+
+        PromiseWrapper.resolve(null).then((_) => log.add('microtask'));
+
+        PromiseWrapper.setTimeout(() => log.add('timer'), 9);
+
+        var id = PromiseWrapper.setInterval(() => log.add('periodic timer'), 10);
+
+        expect(log.result()).toEqual('');
+
+        tick(10);
+        expect(log.result()).toEqual('microtask; timer; periodic timer');
+
+        PromiseWrapper.clearInterval(id);
+      }));
+
+      it('should process micro-tasks created in timers before next timers', fakeAsync(() => {
+        var log = new Log();
+
+        PromiseWrapper.resolve(null).then((_) => log.add('microtask'));
+
+        PromiseWrapper.setTimeout(() => {
+          log.add('timer');
+          PromiseWrapper.resolve(null).then((_) => log.add('t microtask'));
+        }, 9);
+
+        var id = PromiseWrapper.setInterval(() => {
+          log.add('periodic timer');
+          PromiseWrapper.resolve(null).then((_) => log.add('pt microtask'));
+        }, 10);
+
+        tick(10);
+        expect(log.result()).toEqual('microtask; timer; t microtask; periodic timer; pt microtask');
+
+        tick(10);
+        expect(log.result()).toEqual('microtask; timer; t microtask; periodic timer; pt microtask; periodic timer; pt microtask');
+
+        PromiseWrapper.clearInterval(id);
+      }));
+    });
+
+    describe('outside of the fakeAsync zone', () => {
+      it('calling flushMicrotasks should throw', () => {
+        expect(() => {
+          flushMicrotasks();
+        }).toThrowError('The code should be running in the fakeAsync zone to call this function');
+      });
+
+      it('calling tick should throw', () => {
+        expect(() => {
+          tick();
+        }).toThrowError('The code should be running in the fakeAsync zone to call this function');
+      });
+    });
+
+  });
+}

modules/angular2/test_lib.js

@@ -1,2 +1,3 @@
 export * from './src/test_lib/test_lib';
 export * from './src/test_lib/utils';
+export * from './src/test_lib/fake_async';

pubspec.yaml

@@ -4,3 +4,4 @@ environment:
 dev_dependencies:
   guinness: '^0.1.17'
   unittest: '^0.11.5+4'
+  quiver: '^0.21.3+1'

tools/broccoli/trees/node_tree.ts

@@ -22,7 +22,8 @@ module.exports = function makeNodeTree(destinationPath) {
     exclude: [
       // the following code and tests are not compatible with CJS/node environment
       'angular2/src/core/zone/ng_zone.es6',
-      'angular2/test/core/zone/**'
+      'angular2/test/core/zone/**',
+      'angular2/test/test_lib/fake_async_spec.js'
     ]
   });