diff --git a/spec/operators/windowToggle-spec.js b/spec/operators/windowToggle-spec.js
index c320db1e04..2e118931e8 100644
--- a/spec/operators/windowToggle-spec.js
+++ b/spec/operators/windowToggle-spec.js
@@ -7,34 +7,274 @@ describe('Observable.prototype.windowToggle', function () {
     'and closed by an observable returned by the function in the second argument',
   function () {
     var e1 = hot('--1--2--^--a--b--c--d--e--f--g--h--|');
+    var subs =           '^                          !';
     var e2 = cold(       '--------x-------x-------x--|');
-    var e3 = cold(               '----------(x|)');
+    var e3 = cold(               '----------(x|)      ');
     //                                    ----------(x|)
     //                                            ----------(x|)
     var expected =       '--------x-------y-------z--|';
-    var x =              '---------c--d--e--(f|)';
-    var y =              '------------------f--g--h-|';
-    var z =              '---------------------------|';
-
-    var values = {
-      x: Rx.TestScheduler.parseMarbles(x),
-      y: Rx.TestScheduler.parseMarbles(y),
-      z: Rx.TestScheduler.parseMarbles(z)
-    };
+    var x = cold(                '-c--d--e--(f|)      ');
+    var y = cold(                        '--f--g--h-| ');
+    var z = cold(                                '---|');
+    var values = { x: x, y: y, z: z };
 
     var source = e1.windowToggle(e2, function (value) {
       expect(value).toBe('x');
       return e3;
-    }).map(function (obs) {
-      var arr = [];
+    });
+
+    expectObservable(source).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(subs);
+  });
+
+  it('should emit windows using varying cold closings', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|      ');
+    var e2 =     cold('--x-----------y--------z---|              ');
+    var subs =        '^                                  !      ';
+    var closings = [
+      cold(             '---------------s--|                     '),
+      cold(                         '----(s|)                    '),
+      cold(                                  '---------------(s|)')];
+    var expected =    '--x-----------y--------z-----------|      ';
+    var x = cold(       '--b---c---d---e|                        ');
+    var y = cold(                   '--e-|                       ');
+    var z = cold(                            '-g---h------|      ');
+    var values = { x: x, y: y, z: z };
 
-      obs.materialize().map(function (notification) {
-        return { frame: rxTestScheduler.frame, notification: notification };
-      }).subscribe(function (value) { arr.push(value); });
+    var i = 0;
+    var result = e1.windowToggle(e2, function () { return closings[i++]; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(subs);
+  });
 
-      return arr;
+  it('should emit windows using varying hot closings', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|   ');
+    var e2 =     cold('--x-----------y--------z---|           ');
+    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(                   '--e-|                    ');
+    var z = cold(                            '-g---h------|   ');
+    var values = { x: x, y: y, z: z };
+
+    var i = 0;
+    var result = e1.windowToggle(e2, function () { return closings[i++].obs; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(subs);
+    for (var j = 0; j < closings.length; j++) {
+      expectSubscriptions(closings[j].obs.subscriptions).toBe(closings[j].sub);
+    }
+  });
+
+  it('should emit windows using varying empty delayed closings', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|   ');
+    var e2 =     cold('--x-----------y--------z---|           ');
+    var subs =        '^                                  !   ';
+    var closings = [
+      cold(             '---------------|                     '),
+      cold(                         '----|                    '),
+      cold(                                  '---------------|')];
+    var expected =    '--x-----------y--------z-----------|   ';
+    var x = cold(       '--b---c---d---e|                     ');
+    var y = cold(                   '--e-|                    ');
+    var z = cold(                            '-g---h------|   ');
+    var values = { x: x, y: y, z: z };
+
+    var i = 0;
+    var result = e1.windowToggle(e2, function () { return closings[i++]; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(subs);
+  });
+
+  it('should emit windows using varying cold closings, outer unsubscribed early', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|      ');
+    var unsub =       '                  !                       ';
+    var subs =        '^                 !                       ';
+    var e2 =     cold('--x-----------y--------z---|              ');
+    var closings = [
+      cold(             '---------------s--|                     '),
+      cold(                         '----(s|)                    '),
+      cold(                                  '---------------(s|)')];
+    var expected =    '--x-----------y----                    ';
+    var x = cold(       '--b---c---d---e|                     ');
+    var y = cold(                   '--e-|                    ');
+    var values = { x: x, y: y };
+
+    var i = 0;
+    var result = e1.windowToggle(e2, function () { return closings[i++]; });
+
+    expectObservable(result, unsub).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(subs);
+  });
+
+  it('should propagate error thrown from closingSelector', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|      ');
+    var e2 =     cold('--x-----------y--------z---|              ');
+    var subs =        '^             !                           ';
+    var closings = [
+      cold(             '---------------s--|                     '),
+      cold(                         '----(s|)                    '),
+      cold(                                  '---------------(s|)')];
+    var expected =    '--x-----------#----                       ';
+    var x = cold(       '--b---c---d-#                           ');
+    var values = { x: x };
+
+    var i = 0;
+    var result = e1.windowToggle(e2, function () {
+      if (i === 1) {
+        throw 'error';
+      }
+      return closings[i++];
     });
 
-    expectObservable(source).toBe(expected, values);
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(subs);
+  });
+
+  it('should propagate error emitted from a closing', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|');
+    var e2 =     cold('--x-----------y--------z---|        ');
+    var subs =        '^             !                     ';
+    var closings = [
+      cold(             '---------------s--|               '),
+      cold(                         '#                     ')];
+    var expected =    '--x-----------(y#)                  ';
+    var x = cold(       '--b---c---d-#                     ');
+    var y = cold(                   '#                     ');
+    var values = { x: x, y: y };
+
+    var i = 0;
+    var result = e1.windowToggle(e2, function () { return closings[i++]; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(subs);
+  });
+
+  it('should propagate error emitted late from a closing', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|');
+    var e2 =     cold('--x-----------y--------z---|        ');
+    var subs =        '^                  !                ';
+    var closings = [
+      cold(             '---------------s--|               '),
+      cold(                         '-----#                ')];
+    var expected =    '--x-----------y----#                ';
+    var x = cold(       '--b---c---d---e|                  ');
+    var y = cold(                   '--e--#                ');
+    var values = { x: x, y: y };
+
+    var i = 0;
+    var result = e1.windowToggle(e2, function () { return closings[i++]; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(subs);
+  });
+
+  it('should handle errors', function () {
+    var e1 = hot('--a--^---b---c---d---e--#f---g---h------|');
+    var e2 =     cold('--x-----------y--------z---|        ');
+    var subs =        '^                  !                ';
+    var closings = [
+      cold(             '---------------s--|               '),
+      cold(                         '-------s|             ')];
+    var expected =    '--x-----------y----#                ';
+    var x = cold(       '--b---c---d---e|                  ');
+    var y = cold(                   '--e--#                ');
+    var values = { x: x, y: y };
+
+    var i = 0;
+    var result = e1.windowToggle(e2, function () { return closings[i++]; });
+
+    expectObservable(result).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(subs);
+  });
+
+  it('should handle empty source', function () {
+    var e1 = cold( '|');
+    var e2 = cold( '--o-----|');
+    var e3 = cold(   '-----c--|');
+    var expected = '|';
+
+    var result = e1.windowToggle(e2, function () { return e3; });
+
+    expectObservable(result).toBe(expected);
+  });
+
+  it('should handle throw', function () {
+    var e1 = cold('#');
+    var e2 = cold('--o-----|');
+    var e3 = cold('-----c--|');
+    var expected = '#';
+
+    var result = e1.windowToggle(e2, function () { return e3; });
+
+    expectObservable(result).toBe(expected);
+  });
+
+  it('should handle never', function () {
+    var e1 =   hot('-');
+    var e2 =  cold('--o-----o------o-----o---o-----|');
+    var e3 =  cold(  '--c-|');
+    var unsub =    '                                            !';
+    var subs =     '^                                           !';
+    var expected = '--u-----v------x-----y---z-------------------';
+    var u = cold(    '--|                                        ');
+    var v = cold(          '--|                                  ');
+    var x = cold(                 '--|                           ');
+    var y = cold(                       '--|                     ');
+    var z = cold(                           '--|                 ');
+    var values = { u: u, v: v, x: x, y: y, z: z };
+
+    var result = e1.windowToggle(e2, function () { return e3; });
+
+    expectObservable(result, unsub).toBe(expected, values);
+    expectSubscriptions(e1.subscriptions).toBe(subs);
+  });
+
+  it('should handle a never opening Observable', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|');
+    var e2 = cold(    '-');
+    var e3 =  cold(   '--c-|');
+    var expected =    '-----------------------------------|';
+
+    var result = e1.windowToggle(e2, function () { return e3; });
+
+    expectObservable(result).toBe(expected);
+  });
+
+  it('should handle a never closing Observable', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|');
+    var e2 = cold(    '---o---------------o-----------|    ');
+    var e3 =  cold('-');
+    var expected =    '---x---------------y---------------|';
+    var x = cold(        '-b---c---d---e---f---g---h------|');
+    var y = cold(                        '-f---g---h------|');
+    var values = { x: x, y: y };
+
+    var result = e1.windowToggle(e2, function () { return e3; });
+
+    expectObservable(result).toBe(expected, values);
+  });
+
+  it('should handle opening Observable that just throws', function () {
+    var e1 = hot('--a--^---b---c---d---e---f---g---h------|');
+    var e2 = cold(    '#');
+    var e3 = cold(    '--c-|');
+    var subs =        '(^!)';
+    var expected =    '#';
+
+    var result = e1.windowToggle(e2, function () { return e3; });
+
+    expectObservable(result).toBe(expected);
+    expectSubscriptions(e1.subscriptions).toBe(subs);
   });
 });
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