title: How do you unit test Rx operators that use timers?
body: <p>There are a number of operators that are timer based, and I although I don't have a concrete example, would think it common to create new operators that utilise timers.  So how would you go about writing a test that runs synchronously for these operators?  </p>
  
  <p>As an example, how could I go about unit testing an operator such as BufferWithTime?</p>