Re: [git-for-windows] Re: Continuous Testing of Git on Windows

From: Junio C Hamano <gitster@pobox.com>
Date: Feb 15, 2017, 21:26 UTC
Message-ID: <xmqqvasb2li8.fsf@gitster.mtv.corp.google.com>
In-Reply-To: <7EA15219331242ABB08B9A9AA9F08CBE@PhilipOakley>

"Philip Oakley" <philipoakley@iee.org> writes:

Show 7 quoted lines

> In the next..pu case the abstraction is in the other direction, we
> have potentially multiple points of infection (from feature branches),
> and a broad test (the whole test suite). In this case I believe we
> would like to investigate initially the --first-parent line with a
> classic bisect for the first point of failure (obviously including
> feature branch merges). This would identify which feature merge, or
> regular commit, created the first breakage.

If you are going first-parent, you would limit the bisection to a single-strand-of-pearls, and I agree that it is a good strategy to find which topic branch merge broke the tip of 'pu'.

If we assume that there is no funny interaction among topics that cancel a breakage brought in by one topic with another breakage by another topic, then no matter how many broken topics there are, I agree that we would get to the first broken topic.

A good thing that comes once we assume that topics are more-or-less independent is that we could rebuild 'pu' minus the broken topic identified by the above procedure and repeat it to find other broken topics, still using the --first-parent bisection, because master..pu is a linear sequence of merges of individual topics.