From: Derrick Stolee <stolee@gmail.com>
To: Junio C Hamano <gitster@pobox.com>,
Derrick Stolee via GitGitGadget <gitgitgadget@gmail.com>
Cc: git@vger.kernel.org, peff@peff.net, jcoglan@gmail.com,
Derrick Stolee <dstolee@microsoft.com>
Subject: Re: [PATCH 0/2] Graph horizontal fix
Date: Wed, 8 Jan 2020 15:05:50 -0500 [thread overview]
Message-ID: <c69afbe7-3a9c-0619-594f-f5ba980ae7b8@gmail.com> (raw)
In-Reply-To: <xmqq5zhl3jrm.fsf@gitster-ct.c.googlers.com>
On 1/8/2020 1:06 PM, Junio C Hamano wrote:
> "Derrick Stolee via GitGitGadget" <gitgitgadget@gmail.com> writes:
>
>> This depends on ds/graph-assert-fix.
>>
>> This is a non-critical (not needed for v2.25.0) response to the previous
>> discussions [1] [2].
>>
>> While working to resolve the fix for the assert() bug, I noticed this
>> regression when multiple edges wanted to collapse with horizontal lines. It
>> takes a reasonably large graph, but real projects are likely to demonstrate
>> this behavior.
>>
>> I arranged the series into two patches: 1. the (failing) test, and 2. the
>> fix.
>>
>> The fix commit includes some details about why the change to compress merge
>> commits caused this regression, and why I feel relatively confident that
>> this is a correct resolution.
>
> I am not sure if this is "fix" of "bug" in that what is shown
> without 2/2 (iow, "before this change" in the description of 2/2) is
> "wrong" per-se---it is just that it leaves room to be made even more
> compact. It still is an improvement, of course, though.
I guess I was incomplete in my first example. The full horizontal behavior
before 0f0f389f was
| | | | | | *-.
| | | | | | |\ \
| |_|_|_|_|/ | |
|/| | | | | / /
| | |_|_|_|/ /
| |/| | | | /
| | | |_|_|/
| | |/| | |
and 0f0f389f added a compact merge commit, but lost two horizontal lines.
| | | | | | *
| |_|_|_|_|/|\
|/| | | | |/ /
| | | | |/| /
| | | |/| |/
| | |/| |/|
| |/| |/| |
| | |/| | |
This change brings the horizontal lines back.
| | | | | | *
| |_|_|_|_|/|\
|/| | | | |/ /
| | |_|_|/| /
| |/| | | |/
| | | |_|/|
| | |/| | |
Whether this qualifies as a "bug" is debatable, for sure. That's why I
believe this change is below the bar for the release candidate.
Thanks,
-Stolee
next prev parent reply other threads:[~2020-01-08 20:05 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-08 4:27 [PATCH 0/2] Graph horizontal fix Derrick Stolee via GitGitGadget
2020-01-08 4:27 ` [PATCH 1/2] graph: add test to demonstrate horizontal line bug Derrick Stolee via GitGitGadget
2020-01-08 4:27 ` [PATCH 2/2] graph: fix collapse of multiple edges Derrick Stolee via GitGitGadget
2020-01-08 7:25 ` Jeff King
2020-01-08 13:40 ` Derrick Stolee
2020-01-08 13:49 ` Jeff King
2020-01-08 18:06 ` [PATCH 0/2] Graph horizontal fix Junio C Hamano
2020-01-08 20:05 ` Derrick Stolee [this message]
2020-01-08 21:06 ` Junio C Hamano
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
List information: http://vger.kernel.org/majordomo-info.html
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=c69afbe7-3a9c-0619-594f-f5ba980ae7b8@gmail.com \
--to=stolee@gmail.com \
--cc=dstolee@microsoft.com \
--cc=git@vger.kernel.org \
--cc=gitgitgadget@gmail.com \
--cc=gitster@pobox.com \
--cc=jcoglan@gmail.com \
--cc=peff@peff.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://80x24.org/mirrors/git.git
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).