{
      callCount++;
    };
    timeOut.run(callback, 50);
    timeOut.after(50).run(callback);
    timeOut.run(callback, 50);
    timeOut.after(50).run(callback);
    timeOut.run(callback, 200);
    timeOut.after(200).run(callback);
    setTimeout(function() {
      assert.equal(callCount, 4);
      done();
    }, 100); // Only wait until the first two callbacks are called.
  });

  test('All queued functions are run.', function(done) {
    var callCount1 = 0;
    var callCount2 = 0;
    var callCount3 = 0