     th.expectStreamTimings(
       -> th.atGivenTimes([[0, "a"], [3, "b"], [5, "c"]]).bufferWithTime(t(2))
       [[2, ["a"]], [4, ["b"]], [6, ["c"]]]
-      {unstable:true}
+      unstable
     )
   describe "works with empty stream", ->
     expectStreamEvents(

          series(3, [1, 2])
          series(3, [3, 4]).delay(t(1))
          series(3, [5, 6]).delay(t(2)))
      [1, 3, 5, 2, 4, 6], {unstable:true})
  describe "works with a single stream", ->
    expectStreamEvents(
      -> Bacon.mergeAll([Bacon.once(1)])

        Bacon.when(
          [as, bs, cs], (a,b,c) ->  a + b + c,
          [as],         (a)   ->  a)
      ['a', 'ab0', 'a', 'ab1', 'ab2', 'ab3'], unstable)
  describe "doesn't output before properties have values", ->
    expectStreamEvents(
      ->
