On Sun, Sep 15, 2024 at 07:31:15AM -0400, Jeff King wrote: > In the test "cc list is sanitized", we feed a commit with a variety of > trailers to send-email, and then check its output to see how it handled > them. For most of them, we are grepping for a specific mention of the > header, but there's a "BugID" header which we expect to be ignored. We > confirm this by grepping for "12345", the fake BugID, and making sure it > is not present. > > But we can be fooled by false positives! I just tracked down a flaky > test failure here that was caused by matching this unrelated line in the > output: > > <20240914090449.612345-1-author@xxxxxxxxxxx> > > which will change from run to run based on the time, pid, etc. > > Ideally we'd tighten the regex to make this more specifically, but since > the point is that it _shouldn't_ be mentioned, it's hard to say what the > right match would be (e.g., would there be a leading space?). > > Instead, let's just choose a match that is much less likely to appear. > The actual content of the header isn't important, since it's supposed to > be ignored. > > Signed-off-by: Jeff King <peff@xxxxxxxx> > --- > I guess this is fairly unlikely, as re-running the test with --stress > didn't reproduce after a few hundred attempts. Back of the envelope, I > guess any 5-digit sequence has a 1-in-10^5 chance of matching our > target. There are 2 in chances in a 6-digit pid. Some in the date, but > as there's no December 34th or hour 34, you're limited to a few specific > times like 01:23:45 (or at 11am), 12:34:5x, or perhaps 23:45 on the 1st, > 11th, or 21st of the month. > > So I think I just got really unlucky, but after spending several minutes > debugging, I wouldn't want to wish it on anybody else. ;) Heh, unlucky indeed. In any case, the change makes sense to me, thanks! Patrick
