style(q): rename src/Deferred.js to src/service/q.js

1 files changed, 823 insertions, 0 deletions

diff --git a/test/service/qSpec.js b/test/service/qSpec.js
new file mode 100644
index 00000000..e592ab87
--- /dev/null
+++ b/test/service/qSpec.js
@@ -0,0 +1,823 @@
+'use strict';
+
+/**
+  http://wiki.commonjs.org/wiki/Promises
+  http://www.slideshare.net/domenicdenicola/callbacks-promises-and-coroutines-oh-my-the-evolution-of-asynchronicity-in-javascript
+
+  Q:  https://github.com/kriskowal/q
+      https://github.com/kriskowal/q/blob/master/design/README.js
+      https://github.com/kriskowal/uncommonjs/blob/master/promises/specification.md
+      http://jsconf.eu/2010/speaker/commonjs_i_promise_by_kris_kow.html
+        - good walkthrough of the Q api's and design, jump to 15:30
+
+  twisted: http://twistedmatrix.com/documents/11.0.0/api/twisted.internet.defer.Deferred.html
+  dojo: https://github.com/dojo/dojo/blob/master/_base/Deferred.js
+        http://dojotoolkit.org/api/1.6/dojo/Deferred
+        http://dojotoolkit.org/documentation/tutorials/1.6/promises/
+  when.js: https://github.com/briancavalier/when.js
+  DART: http://www.dartlang.org/docs/api/Promise.html#Promise::Promise
+        http://code.google.com/p/dart/source/browse/trunk/dart/corelib/src/promise.dart
+        http://codereview.chromium.org/8271014/patch/11003/12005
+        https://chromereviews.googleplex.com/3365018/
+  WinJS: http://msdn.microsoft.com/en-us/library/windows/apps/br211867.aspx
+
+  http://download.oracle.com/javase/1.5.0/docs/api/java/util/concurrent/Future.html
+  http://en.wikipedia.org/wiki/Futures_and_promises
+  http://wiki.ecmascript.org/doku.php?id=strawman:deferred_functions
+  http://wiki.ecmascript.org/doku.php?id=strawman:async_functions
+
+
+  http://jsperf.com/throw-vs-return
+*/
+
+describe('q', function() {
+  var q, defer, deferred, promise, log;
+
+  /**
+   * Creates a callback that logs its invocation in `log`.
+   *
+   * @param {(number|string)} name Suffix for 'success' name. e.g. success(1) => success1
+   * @param {*=} returnVal Value that the callback should return. If unspecified, the passed in
+   *     value is returned.
+   * @param {boolean=} throwReturnVal If true, the `returnVal` will be thrown rather than returned.
+   */
+  function success(name, returnVal, throwReturnVal) {
+    var returnValDefined = (arguments.length >= 2);
+
+    return function() {
+      name = 'success' + (name || '');
+      var args = toJson(sliceArgs(arguments)).replace(/(^\[|"|\]$)/g, '');
+      log.push(name + '(' +  args + ')');
+      returnVal = returnValDefined ? returnVal : arguments[0];
+      if (throwReturnVal) throw returnVal;
+      return returnVal;
+    }
+  }
+
+
+  /**
+   * Creates a callback that logs its invocation in `log`.
+   *
+   * @param {(number|string)} name Suffix for 'error' name. e.g. error(1) => error1
+   * @param {*=} returnVal Value that the callback should return. If unspecified, the passed in
+   *     value is rethrown.
+   * @param {boolean=} throwReturnVal If true, the `returnVal` will be thrown rather than returned.
+   */
+  function error(name, returnVal, throwReturnVal) {
+    var returnValDefined = (arguments.length >= 2);
+
+    return function(){
+      name = 'error' + (name || '');
+      log.push(name + '(' + [].join.call(arguments, ',') + ')');
+      returnVal = returnValDefined ? returnVal : q.reject(arguments[0]);
+      if (throwReturnVal) throw returnVal;
+      return returnVal;
+    }
+  }
+
+
+  /** helper for synchronous resolution of deferred */
+  function syncResolve(deferred, result) {
+    deferred.resolve(result);
+    mockNextTick.flush();
+  }
+
+
+  /** helper for synchronous rejection of deferred */
+  function syncReject(deferred, reason) {
+    deferred.reject(reason);
+    mockNextTick.flush();
+  }
+
+
+  /** converts the `log` to a '; '-separated string */
+  function logStr() {
+    return log.join('; ');
+  }
+
+
+  var mockNextTick = {
+    nextTick: function(task) {
+      mockNextTick.queue.push(task);
+    },
+    queue: [],
+    flush: function() {
+      if (!mockNextTick.queue.length) throw new Error('Nothing to be flushed!');
+      while (mockNextTick.queue.length) {
+        var queue = mockNextTick.queue;
+        mockNextTick.queue = [];
+        forEach(queue, function(task) {
+          try {
+            task();
+          } catch(e) {
+            dump('exception in mockNextTick:', e, e.name, e.message, task);
+          }
+        });
+      }
+    }
+  }
+
+
+  beforeEach(function() {
+    q = qFactory(mockNextTick.nextTick, noop),
+    defer = q.defer;
+    deferred =  defer()
+    promise = deferred.promise;
+    log = [];
+    mockNextTick.queue = [];
+  });
+
+
+  afterEach(function() {
+    expect(mockNextTick.queue.length).toBe(0);
+  });
+
+
+  describe('defer', function() {
+    it('should create a new deferred', function() {
+      expect(deferred.promise).toBeDefined();
+      expect(deferred.resolve).toBeDefined();
+      expect(deferred.reject).toBeDefined();
+    });
+
+
+    describe('resolve', function() {
+      it('should fulfill the promise and execute all success callbacks in the registration order',
+          function() {
+        promise.then(success(1), error());
+        promise.then(success(2), error());
+        expect(logStr()).toBe('');
+
+        deferred.resolve('foo');
+        mockNextTick.flush();
+        expect(logStr()).toBe('success1(foo); success2(foo)');
+      });
+
+
+      it('should do nothing if a promise was previously resolved', function() {
+        promise.then(success(), error());
+        expect(logStr()).toBe('');
+
+        deferred.resolve('foo');
+        mockNextTick.flush();
+        expect(logStr()).toBe('success(foo)');
+
+        log = [];
+        deferred.resolve('bar');
+        deferred.reject('baz');
+        expect(mockNextTick.queue.length).toBe(0);
+        expect(logStr()).toBe('');
+      });
+
+
+      it('should do nothing if a promise was previously rejected', function() {
+        promise.then(success(), error());
+        expect(logStr()).toBe('');
+
+        deferred.reject('foo');
+        mockNextTick.flush();
+        expect(logStr()).toBe('error(foo)');
+
+        log = [];
+        deferred.resolve('bar');
+        deferred.reject('baz');
+        expect(mockNextTick.queue.length).toBe(0);
+        expect(logStr()).toBe('');
+      });
+
+
+      it('should allow deferred resolution with a new promise', function() {
+        var deferred2 = defer();
+        promise.then(success(), error());
+
+        deferred.resolve(deferred2.promise);
+        mockNextTick.flush();
+        expect(logStr()).toBe('');
+
+        deferred2.resolve('foo');
+        mockNextTick.flush();
+        expect(logStr()).toBe('success(foo)');
+      });
+
+
+      it('should call the callback in the next turn', function() {
+        promise.then(success());
+        expect(logStr()).toBe('');
+
+        deferred.resolve('foo');
+        expect(logStr()).toBe('');
+
+        mockNextTick.flush();
+        expect(logStr()).toBe('success(foo)');
+      });
+
+
+      it('should support non-bound execution', function() {
+        var resolver = deferred.resolve;
+        promise.then(success(), error());
+        resolver('detached');
+        mockNextTick.flush();
+        expect(logStr()).toBe('success(detached)');
+      });
+
+
+      it('should not break if a callbacks registers another callback', function() {
+        promise.then(function() {
+          log.push('outer');
+          promise.then(function() {
+            log.push('inner');
+          });
+        });
+
+        deferred.resolve('foo');
+        expect(logStr()).toBe('');
+
+        mockNextTick.flush();
+        expect(logStr()).toBe('outer; inner');
+      });
+
+
+      it('should not break if a callbacks tries to resolve the deferred again', function() {
+        promise.then(function(val) {
+          log.push('success1(' + val + ')');
+          deferred.resolve('bar');
+        });
+
+        promise.then(success(2));
+
+        deferred.resolve('foo');
+        expect(logStr()).toBe('');
+
+        mockNextTick.flush();
+        expect(logStr()).toBe('success1(foo); success2(foo)');
+      });
+    });
+
+
+    describe('reject', function() {
+      it('should reject the promise and execute all error callbacks in the registration order',
+          function() {
+        promise.then(success(), error(1));
+        promise.then(success(), error(2));
+        expect(logStr()).toBe('');
+
+        deferred.reject('foo');
+        mockNextTick.flush();
+        expect(logStr()).toBe('error1(foo); error2(foo)');
+      });
+
+
+      it('should do nothing if a promise was previously resolved', function() {
+        promise.then(success(1), error(1));
+        expect(logStr()).toBe('');
+
+        deferred.resolve('foo');
+        mockNextTick.flush();
+        expect(logStr()).toBe('success1(foo)');
+
+        log = [];
+        deferred.reject('bar');
+        deferred.resolve('baz');
+        expect(mockNextTick.queue.length).toBe(0);
+        expect(logStr()).toBe('');
+
+        promise.then(success(2), error(2))
+        expect(logStr()).toBe('');
+        mockNextTick.flush();
+        expect(logStr()).toBe('success2(foo)');
+      });
+
+
+      it('should do nothing if a promise was previously rejected', function() {
+        promise.then(success(1), error(1));
+        expect(logStr()).toBe('');
+
+        deferred.reject('foo');
+        mockNextTick.flush();
+        expect(logStr()).toBe('error1(foo)');
+
+        log = [];
+        deferred.reject('bar');
+        deferred.resolve('baz');
+        expect(mockNextTick.queue.length).toBe(0);
+        expect(logStr()).toBe('');
+
+        promise.then(success(2), error(2))
+        expect(logStr()).toBe('');
+        mockNextTick.flush();
+        expect(logStr()).toBe('error2(foo)');
+      });
+
+
+      it('should not defer rejection with a new promise', function() {
+        var deferred2 = defer();
+        promise.then(success(), error());
+
+        deferred.reject(deferred2.promise);
+        mockNextTick.flush();
+        expect(logStr()).toBe('error([object Object])');
+      });
+
+
+      it('should call the error callback in the next turn', function() {
+        promise.then(success(), error());
+        expect(logStr()).toBe('');
+
+        deferred.reject('foo');
+        expect(logStr()).toBe('');
+
+        mockNextTick.flush();
+        expect(logStr()).toBe('error(foo)');
+      });
+
+
+      it('should support non-bound execution', function() {
+        var rejector = deferred.reject;
+        promise.then(success(), error());
+        rejector('detached');
+        mockNextTick.flush();
+        expect(logStr()).toBe('error(detached)');
+      });
+    });
+
+
+    describe('promise', function() {
+      it('should have a then method', function() {
+        expect(typeof promise.then).toBe('function');
+      });
+
+
+      describe('then', function() {
+        it('should allow registration of a success callback without an errback and resolve',
+            function() {
+          promise.then(success());
+          syncResolve(deferred, 'foo');
+          expect(logStr()).toBe('success(foo)');
+        });
+
+        it('should allow registration of a success callback without an errback and reject',
+            function() {
+          promise.then(success());
+          syncReject(deferred, 'foo');
+          expect(logStr()).toBe('');
+        });
+
+
+        it('should allow registration of an errback without a success callback and reject',
+            function() {
+          promise.then(null, error());
+          syncReject(deferred, 'oops!');
+          expect(logStr()).toBe('error(oops!)');
+        });
+
+
+        it('should allow registration of an errback without a success callback and resolve',
+            function() {
+          promise.then(null, error());
+          syncResolve(deferred, 'done');
+          expect(logStr()).toBe('');
+        });
+
+
+        it('should resolve all callbacks with the original value', function() {
+          promise.then(success('A', 'aVal'), error());
+          promise.then(success('B', 'bErr', true), error());
+          promise.then(success('C', q.reject('cReason')), error());
+          promise.then(success('D', 'dVal'), error());
+
+          expect(logStr()).toBe('');
+          syncResolve(deferred, 'yup');
+          expect(logStr()).toBe('successA(yup); successB(yup); successC(yup); successD(yup)');
+        });
+
+
+        it('should reject all callbacks with the original reason', function() {
+          promise.then(success(), error('A', 'aVal'));
+          promise.then(success(), error('B', 'bEr', true));
+          promise.then(success(), error('C', q.reject('cReason')));
+          promise.then(success(), error('D', 'dVal'));
+
+          expect(logStr()).toBe('');
+          syncReject(deferred, 'noo!');
+          expect(logStr()).toBe('errorA(noo!); errorB(noo!); errorC(noo!); errorD(noo!)');
+        });
+
+
+        it('should propagate resolution and rejection between dependent promises', function() {
+          promise.then(success(1, 'x'), error('1')).
+                  then(success(2, 'y', true), error('2')).
+                  then(success(3), error(3, 'z', true)).
+                  then(success(4), error(4, 'done')).
+                  then(success(5), error(5));
+
+          expect(logStr()).toBe('');
+          syncResolve(deferred, 'sweet!');
+          expect(log).toEqual(['success1(sweet!)',
+                               'success2(x)',
+                               'error3(y)',
+                               'error4(z)',
+                               'success5(done)']);
+        });
+
+
+        it('should reject a derived promise if an exception is thrown while resolving its parent',
+            function() {
+          promise.then(success(1, 'oops', true)).
+                  then(success(2), error(2));
+          syncResolve(deferred, 'done!');
+          expect(logStr()).toBe('success1(done!); error2(oops)');
+        });
+
+
+        it('should reject a derived promise if an exception is thrown while rejecting its parent',
+            function() {
+          promise.then(null, error(1, 'oops', true)).
+                  then(success(2), error(2));
+          syncReject(deferred, 'timeout');
+          expect(logStr()).toBe('error1(timeout); error2(oops)');
+        });
+
+
+        it('should call success callback in the next turn even if promise is already resolved',
+            function() {
+          deferred.resolve('done!');
+
+          promise.then(success());
+          expect(logStr()).toBe('');
+
+          mockNextTick.flush();
+          expect(log).toEqual(['success(done!)']);
+        });
+
+
+        it('should call errpr callback in the next turn even if promise is already rejected',
+            function() {
+          deferred.reject('oops!');
+
+          promise.then(null, error());
+          expect(logStr()).toBe('');
+
+          mockNextTick.flush();
+          expect(log).toEqual(['error(oops!)']);
+        });
+      });
+    });
+  });
+
+
+  describe('reject', function() {
+    it('should package a string into a rejected promise', function() {
+      var rejectedPromise = q.reject('not gonna happen');
+      promise.then(success(), error());
+      syncResolve(deferred, rejectedPromise);
+      expect(log).toEqual(['error(not gonna happen)']);
+    });
+
+
+    it('should package an exception into a rejected promise', function() {
+      var rejectedPromise = q.reject(Error('not gonna happen'));
+      promise.then(success(), error());
+      syncResolve(deferred, rejectedPromise);
+      expect(log).toEqual(['error(Error: not gonna happen)']);
+    });
+  });
+
+
+  describe('when', function() {
+    describe('resolution', function() {
+      it('should call the success callback in the next turn when the value is a non-promise',
+          function() {
+        q.when('hello', success(), error());
+        expect(logStr()).toBe('');
+        mockNextTick.flush();
+        expect(logStr()).toBe('success(hello)');
+      });
+
+
+      it('should call the success callback in the next turn when the value is a resolved promise',
+          function() {
+        deferred.resolve('hello');
+        q.when(deferred.promise, success(), error());
+        expect(logStr()).toBe('');
+        mockNextTick.flush();
+        expect(logStr()).toBe('success(hello)');
+      });
+
+
+      it('should call the errback in the next turn when the value is a rejected promise', function() {
+        deferred.reject('nope');
+        q.when(deferred.promise, success(), error());
+        expect(logStr()).toBe('');
+        mockNextTick.flush();
+        expect(logStr()).toBe('error(nope)');
+      });
+
+
+      it('should call the success callback after the original promise is resolved',
+          function() {
+        q.when(deferred.promise, success(), error());
+        expect(logStr()).toBe('');
+        mockNextTick.flush();
+        expect(logStr()).toBe('');
+        syncResolve(deferred, 'hello');
+        expect(logStr()).toBe('success(hello)');
+      });
+
+
+      it('should call the errback after the orignal promise is rejected',
+          function() {
+        q.when(deferred.promise, success(), error());
+        expect(logStr()).toBe('');
+        mockNextTick.flush();
+        expect(logStr()).toBe('');
+        syncReject(deferred, 'nope');
+        expect(logStr()).toBe('error(nope)');
+      });
+    });
+
+
+    describe('optional callbacks', function() {
+      it('should not require success callback and propagate resolution', function() {
+        q.when('hi', null, error()).then(success(2), error());
+        expect(logStr()).toBe('');
+        mockNextTick.flush();
+        expect(logStr()).toBe('success2(hi)');
+      });
+
+
+      it('should not require success callback and propagate rejection', function() {
+        q.when(q.reject('sorry'), null, error(1)).then(success(), error(2));
+        expect(logStr()).toBe('');
+        mockNextTick.flush();
+        expect(logStr()).toBe('error1(sorry); error2(sorry)');
+      });
+
+
+      it('should not require errback and propagate resolution', function() {
+        q.when('hi', success(1, 'hello')).then(success(2), error());
+        expect(logStr()).toBe('');
+        mockNextTick.flush();
+        expect(logStr()).toBe('success1(hi); success2(hello)');
+      });
+
+
+      it('should not require errback and propagate rejection', function() {
+        q.when(q.reject('sorry'), success()).then(success(2), error(2));
+        expect(logStr()).toBe('');
+        mockNextTick.flush();
+        expect(logStr()).toBe('error2(sorry)');
+      });
+    });
+
+
+    describe('returned promise', function() {
+      it('should return a promise that can be resolved with a value returned from the success ' +
+          'callback', function() {
+        q.when('hello', success(1, 'hi'), error()).then(success(2), error());
+        mockNextTick.flush();
+        expect(logStr()).toBe('success1(hello); success2(hi)');
+      });
+
+
+      it('should return a promise that can be rejected with a rejected promise returned from the ' +
+          'success callback', function() {
+        q.when('hello', success(1, q.reject('sorry')), error()).then(success(), error(2));
+        mockNextTick.flush();
+        expect(logStr()).toBe('success1(hello); error2(sorry)');
+      });
+
+
+      it('should return a promise that can be resolved with a value returned from the errback',
+          function() {
+        q.when(q.reject('sorry'), success(), error(1, 'hi')).then(success(2), error());
+        mockNextTick.flush();
+        expect(logStr()).toBe('error1(sorry); success2(hi)');
+      });
+
+
+      it('should return a promise that can be rejected with a rejected promise returned from the ' +
+          'errback', function() {
+        q.when(q.reject('sorry'), success(), error(1, q.reject('sigh'))).then(success(), error(2));
+        mockNextTick.flush();
+        expect(logStr()).toBe('error1(sorry); error2(sigh)');
+      });
+
+
+      it('should return a promise that can be resolved with a promise returned from the success ' +
+          'callback', function() {
+        var deferred2 = defer();
+        q.when('hi', success(1, deferred2.promise), error()).then(success(2), error());
+        mockNextTick.flush();
+        expect(logStr()).toBe('success1(hi)');
+        syncResolve(deferred2, 'finally!');
+        expect(logStr()).toBe('success1(hi); success2(finally!)');
+      });
+
+
+      it('should return a promise that can be resolved with promise returned from the errback ' +
+          'callback', function() {
+        var deferred2 = defer();
+        q.when(q.reject('sorry'), success(), error(1, deferred2.promise)).then(success(2), error());
+        mockNextTick.flush();
+        expect(logStr()).toBe('error1(sorry)');
+        syncResolve(deferred2, 'finally!');
+        expect(logStr()).toBe('error1(sorry); success2(finally!)');
+      });
+    });
+
+
+    describe('security', function() {
+      it('should call success callback only once even if the original promise gets fullfilled ' +
+          'multiple times', function() {
+        var evilPromise = {
+          then: function(success, error) {
+            evilPromise.success = success;
+            evilPromise.error = error;
+          }
+        }
+
+        q.when(evilPromise, success(), error());
+        mockNextTick.flush();
+        expect(logStr()).toBe('');
+        evilPromise.success('done');
+        mockNextTick.flush(); // TODO(i) wrong queue, evil promise would be resolved outside of the
+                              //   scope.$apply lifecycle and in that case we should have some kind
+                              //   of fallback queue for calling our callbacks from. Otherwise the
+                              //   application will get stuck until something triggers next $apply.
+        expect(logStr()).toBe('success(done)');
+
+        evilPromise.success('evil is me');
+        evilPromise.error('burn burn');
+        expect(logStr()).toBe('success(done)');
+      });
+
+
+      it('should call errback only once even if the original promise gets fullfilled multiple ' +
+          'times', function() {
+        var evilPromise = {
+          then: function(success, error) {
+            evilPromise.success = success;
+            evilPromise.error = error;
+          }
+        }
+
+        q.when(evilPromise, success(), error());
+        mockNextTick.flush();
+        expect(logStr()).toBe('');
+        evilPromise.error('failed');
+        expect(logStr()).toBe('error(failed)');
+
+        evilPromise.error('muhaha');
+        evilPromise.success('take this');
+        expect(logStr()).toBe('error(failed)');
+      });
+    });
+  });
+
+
+  describe('all', function() {
+    it('should take an array of promises and return a promise for an array of results', function() {
+      var deferred1 = defer(),
+          deferred2 = defer();
+
+      q.all([promise, deferred1.promise, deferred2.promise]).then(success(), error());
+      expect(logStr()).toBe('');
+      syncResolve(deferred, 'hi');
+      expect(logStr()).toBe('');
+      syncResolve(deferred2, 'cau');
+      expect(logStr()).toBe('');
+      syncResolve(deferred1, 'hola');
+      expect(logStr()).toBe('success([hi,hola,cau])');
+    });
+
+
+    it('should reject the derived promise if at least one of the promises in the array is rejected',
+        function() {
+      var deferred1 = defer(),
+          deferred2 = defer();
+
+      q.all([promise, deferred1.promise, deferred2.promise]).then(success(), error());
+      expect(logStr()).toBe('');
+      syncResolve(deferred2, 'cau');
+      expect(logStr()).toBe('');
+      syncReject(deferred1, 'oops');
+      expect(logStr()).toBe('error(oops)');
+    });
+
+
+    it('should ignore multiple resolutions of an (evil) array promise', function() {
+      var evilPromise = {
+        then: function(success, error) {
+          evilPromise.success = success;
+          evilPromise.error = error;
+        }
+      }
+
+      q.all([promise, evilPromise]).then(success(), error());
+      expect(logStr()).toBe('');
+
+      evilPromise.success('first');
+      evilPromise.success('muhaha');
+      evilPromise.error('arghhh');
+      expect(logStr()).toBe('');
+
+      syncResolve(deferred, 'done');
+      expect(logStr()).toBe('success([done,first])');
+    });
+  });
+
+
+  describe('exception logging', function() {
+    var mockExceptionLogger = {
+      log: [],
+      logger: function(e) {
+        mockExceptionLogger.log.push(e);
+      }
+    }
+
+
+    beforeEach(function() {
+      q = qFactory(mockNextTick.nextTick, mockExceptionLogger.logger),
+      defer = q.defer;
+      deferred =  defer()
+      promise = deferred.promise;
+      log = [];
+      mockExceptionLogger.log = [];
+    });
+
+
+    describe('in then', function() {
+      it('should log exceptions thrown in a success callback and reject the derived promise',
+          function() {
+        var success1 = success(1, 'oops', true);
+        promise.then(success1).then(success(2), error(2));
+        syncResolve(deferred, 'done');
+        expect(logStr()).toBe('success1(done); error2(oops)');
+        expect(mockExceptionLogger.log).toEqual(['oops']);
+      });
+
+
+      it('should NOT log exceptions when a success callback returns rejected promise', function() {
+        promise.then(success(1, q.reject('rejected'))).then(success(2), error(2));
+        syncResolve(deferred, 'done');
+        expect(logStr()).toBe('success1(done); error2(rejected)');
+        expect(mockExceptionLogger.log).toEqual([]);
+      });
+
+
+      it('should log exceptions thrown in a errback and reject the derived promise', function() {
+        var error1 = error(1, 'oops', true);
+        promise.then(null, error1).then(success(2), error(2));
+        syncReject(deferred, 'nope');
+        expect(logStr()).toBe('error1(nope); error2(oops)');
+        expect(mockExceptionLogger.log).toEqual(['oops']);
+      });
+
+
+      it('should NOT log exceptions when an errback returns a rejected promise', function() {
+        promise.then(null, error(1, q.reject('rejected'))).then(success(2), error(2));
+        syncReject(deferred, 'nope');
+        expect(logStr()).toBe('error1(nope); error2(rejected)');
+        expect(mockExceptionLogger.log).toEqual([]);
+      });
+    });
+
+
+    describe('in when', function() {
+      it('should log exceptions thrown in a success callback and reject the derived promise',
+          function() {
+        var success1 = success(1, 'oops', true);
+        q.when('hi', success1, error()).then(success(), error(2));
+        mockNextTick.flush();
+        expect(logStr()).toBe('success1(hi); error2(oops)');
+        expect(mockExceptionLogger.log).toEqual(['oops']);
+      });
+
+
+      it('should NOT log exceptions when a success callback returns rejected promise', function() {
+        q.when('hi', success(1, q.reject('rejected'))).then(success(2), error(2));
+        mockNextTick.flush();
+        expect(logStr()).toBe('success1(hi); error2(rejected)');
+        expect(mockExceptionLogger.log).toEqual([]);
+      });
+
+
+      it('should log exceptions thrown in a errback and reject the derived promise', function() {
+        var error1 = error(1, 'oops', true);
+        q.when(q.reject('sorry'), success(), error1).then(success(), error(2));
+        mockNextTick.flush();
+        expect(logStr()).toBe('error1(sorry); error2(oops)');
+        expect(mockExceptionLogger.log).toEqual(['oops']);
+      });
+
+
+      it('should NOT log exceptions when an errback returns a rejected promise', function() {
+        q.when(q.reject('sorry'), success(), error(1, q.reject('rejected'))).
+          then(success(2), error(2));
+        mockNextTick.flush();
+        expect(logStr()).toBe('error1(sorry); error2(rejected)');
+        expect(mockExceptionLogger.log).toEqual([]);
+      });
+    });
+  });
+});