From: Junio C Hamano <gitster@pobox.com>
Date: Fri, 25 Sep 2015 15:50:07 GMT
Subject: Re: [PATCH] t5561: get rid of racy appending to logfile
Message-ID: <xmqqbncq5wi8.fsf@gitster.mtv.corp.google.com>
In-Reply-To: <1443118342-3856-1-git-send-email-s-beyer@gmx.net>

Stephan Beyer <s-beyer@gmx.net> writes:

> The definition of log_div() appended information to the web server's
> logfile to make the test more readable. However, log_div() was called
> right after a request is served (which is done by git-http-backend);
> the web server waits for the git-http-backend process to exit before
> it writes to the log file. When the duration between serving a request
> and exiting was long, the log_div() output was written before the last
> request's log, and the test failed. (This duration could become
> especially long for PROFILE=GEN builds.)
>
> To get rid of this behavior, we should not change the logfile at all.
> This commit removes log_div() and its calls. The additional information
> is kept in the test (for readability reasons) but filtered out before
> comparing it to the actual logfile.
>
> Signed-off-by: Stephan Beyer <s-beyer@gmx.net>
> ---
>  Okay Peff, I added the information to the commit message (in my own
>  words). Past tense for the situation before the patch, present tense
>  for the situation after (hope that's right but should not be too
>  important).
>
>  I also used your proposed grep line because it is probably more robust.

Thanks, both.  

I vaguely recall this test mysteriously failing a few times during
the past several years for me.  Thanks for digging to the bottom of
the problem.  Both the diagnosis and fix look very sensible.