Tracker test sometimes fails

When running the tests for the Tracker module, I get one failed test in about half the times I try (the rest of the time, all tests pass):

111 passes, 1 fail, 0 exceptions

Message:   New comments are counted on the tracker listing pages.
Group:     Other
Filename:  tracker.test
Line:      140
Function:  TrackerTest->testTrackerNewComments()

I believe this happens because the test runs "too fast". testTrackerNewComments() posts a comment as one user, then posts a comment as another user and finally gets the tracker of the first user. If all this happens within the same second, the two comments get the same timestamp. AFAICT comment_num_new() doesn't detect that the second comment was added later than the first and returns 0 even though it should return 1.

If you have troubles reproducing this, you can "make the seconds longer" by adding the following to the top of index.php: $_SERVER['REQUEST_TIME'] -= $_SERVER['REQUEST_TIME'] % 10;

As long as the comment module doesn't offer subsecond precision, we might just add a sleep(1) to the test between the posting of the two comments.