diff --git a/spec/spec-helper.coffee b/spec/spec-helper.coffee
index 44d8b4460..685210c4f 100644
--- a/spec/spec-helper.coffee
+++ b/spec/spec-helper.coffee
@@ -64,6 +64,7 @@ beforeEach ->
   atom.project.setPaths([specProjectPath])
 
   window.resetTimeouts()
+  spyOn(Date, 'now').andCallFake -> window.now
   spyOn(_._, "now").andCallFake -> window.now
   spyOn(window, "setTimeout").andCallFake window.fakeSetTimeout
   spyOn(window, "clearTimeout").andCallFake window.fakeClearTimeout
@@ -186,6 +187,8 @@ jasmine.useRealClock = ->
 jasmine.useMockClock = ->
   spyOn(window, 'setInterval').andCallFake(fakeSetInterval)
   spyOn(window, 'clearInterval').andCallFake(fakeClearInterval)
+  spyOn(Date, 'now').andCallFake(-> window.now)
+
 
 addCustomMatchers = (spec) ->
   spec.addMatchers