diff --git a/spec/operators/windowWhen-spec.js b/spec/operators/windowWhen-spec.js
index 38a6be60c3..d5b8804855 100644
--- a/spec/operators/windowWhen-spec.js
+++ b/spec/operators/windowWhen-spec.js
@@ -5,33 +5,301 @@ var Observable = Rx.Observable;
 describe('Observable.prototype.windowWhen', function () {
   it('should emit windows that close and reopen', function () {
     var e1 = hot('--a--^--b--c--d--e--f--g--h--i--|');
-    var e2 = cold(    '-----------(x|)');
-    //                            -----------(x|)
-    // a              '---b--c--d-|');
-    var a =           '---b--c--d-|';
-    // b                         '-e--f--g--h|')
-    var b =           '------------e--f--g--h|';
-    // c                                    '--i--|'
-    var c =           '------------------------i--|';
+    var e1subs =      '^                          !';
+    var e2 = cold(    '-----------(x|)             ');
+    var e2subs =     ['^          !                ',
+                      '           ^          !     ',
+                      '                      ^    !'];
+    var a = cold(     '---b--c--d-|                ');
+    var b = cold(                '-e--f--g--h|     ');
+    var c = cold(                           '--i--|');
     var expected =    'a----------b----------c----|';
+    var values = { a: a, b: b, c: c };
 
-    var values = {
-      a: Rx.TestScheduler.parseMarbles(a),
-      b: Rx.TestScheduler.parseMarbles(b),
-      c: Rx.TestScheduler.parseMarbles(c)
-    };
+    var source = e1.windowWhen(function () { return e2; });
 
-    var source = e1.windowWhen(function () { return e2; })
-      .map(function (x) {
-        var arr = [];
+    expectObservable(source).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    expectSubscriptions(e2.subscriptions).toBe(e2subs);
+  });
 
-        x.materialize().map(function (notification) {
-          return { frame: rxTestScheduler.frame, notification: notification };
-        }).subscribe(function (value) { arr.push(value); });
+  it('should emit windows using varying cold closings', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|     ');
+    var e1subs =      '^                                  !     ';
+    var closings = [
+      cold(           '-----------------s--|                    '),
+      cold(                            '-----(s|)               '),
+      cold(                                 '---------------(s|)')];
+    var closeSubs =  ['^                !                       ',
+                      '                 ^    !                  ',
+                      '                      ^            !     '];
+    var expected =    'x----------------y----z------------|     ';
+    var x = cold(     '----b---c---d---e|                       ');
+    var y = cold(                      '---f-|                  ');
+    var z = cold(                           '--g---h------|     ');
+    var values = { x: x, y: y, z: z };
 
-        return arr;
-      });
+    var i = 0;
+    var result = e1.windowWhen(function () { return closings[i++]; });
 
-    expectObservable(source).toBe(expected, values);
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    expectSubscriptions(closings[0].subscriptions).toBe(closeSubs[0]);
+    expectSubscriptions(closings[1].subscriptions).toBe(closeSubs[1]);
+    expectSubscriptions(closings[2].subscriptions).toBe(closeSubs[2]);
+  });
+
+  it('should emit windows using varying hot closings', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|   ');
+    var subs =        '^                                  !   ';
+    var closings = [
+      {obs: hot(  '-1--^----------------s-|                   '), // eslint-disable-line key-spacing
+       sub:           '^                !                     '}, // eslint-disable-line key-spacing
+      {obs: hot(      '-----3----4-----------(s|)             '), // eslint-disable-line key-spacing
+       sub:           '                 ^    !                '}, // eslint-disable-line key-spacing
+      {obs: hot(      '-------3----4-------5----------------s|'), // eslint-disable-line key-spacing
+       sub:           '                      ^            !   '}]; // eslint-disable-line key-spacing
+    var expected =    'x----------------y----z------------|   ';
+    var x = cold(     '----b---c---d---e|                     ');
+    var y = cold(                      '---f-|                ');
+    var z = cold(                           '--g---h------|   ');
+    var values = { x: x, y: y, z: z };
+
+    var i = 0;
+    var result = e1.windowWhen(function () { return closings[i++].obs; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(subs);
+    expectSubscriptions(closings[0].obs.subscriptions).toBe(closings[0].sub);
+    expectSubscriptions(closings[1].obs.subscriptions).toBe(closings[1].sub);
+    expectSubscriptions(closings[2].obs.subscriptions).toBe(closings[2].sub);
+  });
+
+  it('should emit windows using varying empty delayed closings', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|  ');
+    var e1subs =      '^                                  !  ';
+    var closings = [
+      cold(           '-----------------|                    '),
+      cold(                            '-----|               '),
+      cold(                                 '---------------|')];
+    var closeSubs =  ['^                !                    ',
+                      '                 ^    !               ',
+                      '                      ^            !  '];
+    var expected =    'x----------------y----z------------|  ';
+    var x = cold(     '----b---c---d---e|                    ');
+    var y = cold(                      '---f-|               ');
+    var z = cold(                           '--g---h------|  ');
+    var values = { x: x, y: y, z: z };
+
+    var i = 0;
+    var result = e1.windowWhen(function () { return closings[i++]; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    expectSubscriptions(closings[0].subscriptions).toBe(closeSubs[0]);
+    expectSubscriptions(closings[1].subscriptions).toBe(closeSubs[1]);
+    expectSubscriptions(closings[2].subscriptions).toBe(closeSubs[2]);
+  });
+
+  it('should emit windows using varying cold closings, outer unsubscribed early', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|     ');
+    var e1subs =      '^                  !                     ';
+    var unsub =       '                   !                     ';
+    var closings = [
+      cold(           '-----------------s--|                    '),
+      cold(                            '-----(s|)               ')];
+    var closeSubs =  ['^                !                       ',
+                      '                 ^ !                     '];
+    var expected =    'x----------------y--                     ';
+    var x = cold(     '----b---c---d---e|                       ');
+    var y = cold(                      '---                     ');
+    var values = { x: x, y: y };
+
+    var i = 0;
+    var result = e1.windowWhen(function () { return closings[i++]; });
+
+    expectObservable(result, unsub).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    expectSubscriptions(closings[0].subscriptions).toBe(closeSubs[0]);
+    expectSubscriptions(closings[1].subscriptions).toBe(closeSubs[1]);
+  });
+
+  it('should propagate error thrown from closingSelector', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|     ');
+    var e1subs =      '^                !                       ';
+    var closings = [
+      cold(           '-----------------s--|                    '),
+      cold(                            '-----(s|)               '),
+      cold(                                 '---------------(s|)')];
+    var closeSubs =  ['^                !                       '];
+    var expected =    'x----------------(y#)                    ';
+    var x = cold(     '----b---c---d---e|                       ');
+    var y = cold(                      '#                       ');
+    var values = { x: x, y: y };
+
+    var i = 0;
+    var result = e1.windowWhen(function () {
+      if (i === 1) {
+        throw 'error';
+      }
+      return closings[i++];
+    });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    expectSubscriptions(closings[0].subscriptions).toBe(closeSubs[0]);
+  });
+
+  it('should propagate error emitted from a closing', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|     ');
+    var e1subs =      '^                !                       ';
+    var closings = [
+      cold(           '-----------------s--|                    '),
+      cold(                            '#                       ')];
+    var closeSubs =  ['^                !                       ',
+                      '                 (^!)                    '];
+    var expected =    'x----------------(y#)                    ';
+    var x = cold(     '----b---c---d---e|                       ');
+    var y = cold(                      '#                       ');
+    var values = { x: x, y: y };
+
+    var i = 0;
+    var result = e1.windowWhen(function () { return closings[i++]; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    expectSubscriptions(closings[0].subscriptions).toBe(closeSubs[0]);
+    expectSubscriptions(closings[1].subscriptions).toBe(closeSubs[1]);
+  });
+
+  it('should propagate error emitted late from a closing', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|     ');
+    var e1subs =      '^                     !                  ';
+    var closings = [
+      cold(           '-----------------s--|                    '),
+      cold(                            '-----#                  ')];
+    var closeSubs =  ['^                !                       ',
+                      '                 ^    !                  '];
+    var expected =    'x----------------y----#                  ';
+    var x = cold(     '----b---c---d---e|                       ');
+    var y = cold(                      '---f-#                  ');
+    var values = { x: x, y: y };
+
+    var i = 0;
+    var result = e1.windowWhen(function () { return closings[i++]; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    expectSubscriptions(closings[0].subscriptions).toBe(closeSubs[0]);
+    expectSubscriptions(closings[1].subscriptions).toBe(closeSubs[1]);
+  });
+
+  it('should propagate errors emitted from the source', function () {
+    var e1 = hot('--a--^---b---c---d---e---f-#                  ');
+    var e1subs =      '^                     !                  ';
+    var closings = [
+      cold(           '-----------------s--|                    '),
+      cold(                            '-------(s|)             ')];
+    var closeSubs =  ['^                !                       ',
+                      '                 ^    !                  '];
+    var expected =    'x----------------y----#                  ';
+    var x = cold(     '----b---c---d---e|                       ');
+    var y = cold(                      '---f-#                  ');
+    var values = { x: x, y: y };
+
+    var i = 0;
+    var result = e1.windowWhen(function () { return closings[i++]; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    expectSubscriptions(closings[0].subscriptions).toBe(closeSubs[0]);
+    expectSubscriptions(closings[1].subscriptions).toBe(closeSubs[1]);
+  });
+
+  it('should handle empty source', function () {
+    var e1 = cold( '|');
+    var e1subs =   '(^!)';
+    var e2 = cold( '-----c--|');
+    var e2subs =   '(^!)';
+    var expected = '(w|)';
+    var values = { w: cold('|') };
+
+    var result = e1.windowWhen(function () { return e2; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    expectSubscriptions(e2.subscriptions).toBe(e2subs);
+  });
+
+  it('should handle a never source', function () {
+    var e1 = cold( '-');
+    var unsub =    '                 !';
+    var e1subs =   '^                !';
+    var e2 = cold( '-----c--|');
+    //                   -----c--|
+    //                        -----c--|
+    //                             -----c--|
+    var e2subs =  ['^    !            ',
+                   '     ^    !       ',
+                   '          ^    !  ',
+                   '               ^ !'];
+    var win = cold('-----|');
+    var d =   cold(               '---');
+    var expected = 'a----b----c----d--';
+    var values = { a: win, b: win, c: win, d: d };
+
+    var result = e1.windowWhen(function () { return e2; });
+
+    expectObservable(result, unsub).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    expectSubscriptions(e2.subscriptions).toBe(e2subs);
+  });
+
+  it('should handle throw', function () {
+    var e1 = cold('#');
+    var e1subs =  '(^!)';
+    var e2 = cold('-----c--|');
+    var e2subs =  '(^!)';
+    var win = cold('#');
+    var expected = '(w#)';
+    var values = { w: win };
+
+    var result = e1.windowWhen(function () { return e2; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    expectSubscriptions(e2.subscriptions).toBe(e2subs);
+  });
+
+  it('should handle a never closing Observable', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|');
+    var e1subs =      '^                                  !';
+    var e2 =  cold(   '-');
+    var e2subs =      '^                                  !';
+    var expected =    'x----------------------------------|';
+    var x = cold(     '----b---c---d---e---f---g---h------|');
+    var values = { x: x };
+
+    var result = e1.windowWhen(function () { return e2; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    expectSubscriptions(e2.subscriptions).toBe(e2subs);
+  });
+
+  it('should handle a throw closing Observable', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|');
+    var e1subs =      '(^!)                                ';
+    var e2 =  cold(   '#');
+    var e2subs =      '(^!)                                ';
+    var expected =    '(x#)                                ';
+    var x = cold(     '#                                   ');
+    var values = { x: x };
+
+    var result = e1.windowWhen(function () { return e2; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    expectSubscriptions(e2.subscriptions).toBe(e2subs);
   });
 });
\ No newline at end of file