git@vger.kernel.org list mirror (unofficial, one of many)
 help / color / mirror / code / Atom feed
From: Johannes Schindelin <Johannes.Schindelin@gmx.de>
To: Junio C Hamano <gitster@pobox.com>
Cc: Johannes Schindelin via GitGitGadget <gitgitgadget@gmail.com>,
	git@vger.kernel.org, Jeff Hostetler <git@jeffhostetler.com>,
	Jeff King <peff@peff.net>
Subject: Re: [PATCH v5 1/9] Start to implement a built-in version of `git add --interactive`
Date: Mon, 11 Nov 2019 10:15:00 +0100 (CET)	[thread overview]
Message-ID: <nycvar.QRO.7.76.6.1911110949590.46@tvgsbejvaqbjf.bet> (raw)
In-Reply-To: <xmqqtv7cjj2n.fsf@gitster-ct.c.googlers.com>

Hi Junio,

On Sun, 10 Nov 2019, Junio C Hamano wrote:

> Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
>
> > I reworded the commit message:
> >
> >     Start to implement a built-in version of `git add --interactive`
> >
> >     To convert the interactive `add` to C, we start with a bare-bones
> >     version of the built-in interactive add, guarded by the new
> >     `add.interactive.useBuiltin` config variable, and then add more and more
> >     functionality to it, until it is feature complete.
> >
> >     This is in contrast to previous conversions to C, where we started with
> >     a built-in helper that spawns the script by default, but optionally
> >     executes the C code instead. The sole reason for this deviation from
> >     previous practice is that on Windows (where such a conversion has the
> >     most benefits in terms of speed and robustness) we face the very
> >     specific problem that a `system()` call in Perl seems to close `stdin`
> >     in the parent process when the spawned process consumes even one
> >     character from `stdin`. And that just does not work for us here, as it
> >     would stop the main loop as soon as any interactive command was
> >     performed by the helper. Which is almost all of the commands in `git add
> >     -i`.
> >
> >     It is almost as if Perl told us once again that it does not want us to
> >     use it on Windows.
> >
> >     At this point, the built-in version of `git add -i` only states that it
> >     cannot do anything yet ;-)
> >
> > Hopefully you like this one better?
>
> Not really.  I find the "we could do the other way but we don't, and
> I hate Perl" totally irrelevant and misleading.

Okay, I understand that you take exception at my criticism of Git's use
of Perl, and I fully understand that you think I blame you for it
because you added most of it.

And I agree that this sidetrack is totally irrelevant for the patch
under discussion.

I do think, however, that the discussion of "we wanted to do it the
other way, but when we tried, it did not work" is relevant, even if I
shortened it to "we use a different approach than previous conversions,
because that previous approach would not work".

Truth be told: I would have _much rather_ stayed with the previous
`--helper` approach, as that would have made it possible to have a
passing test suite at every step, with and without
`GIT_TEST_ADD_I_USE_BUILTIN=true`.

The "let GIT_TEST_ADD_I_USE_BUILTIN=true use the built-in even for
functions we _know_ are not implemented" way only gives us the full
comfort of a passing test suite at the very end of all six patch series,
if which the patch series we are currently discussing is merely the
first.

If I was a reviewer of this patch series rather than the sender, I would
be a bit uncomfortable with the fact that `GIT_TEST_ADD_I_USE_BUILTIN`
cannot be added to the CI/PR builds' `linux-gcc` over-job, not until
much, much later. In fact, it can only be added as the very last patch
in the very last of the six patch series.

And as I write this, I realize that I never spelled that out in the
commit message, and it is a rather important point for reviewers to see
addressed pre-emptively, in my opinion.

Therefore I revised the commit message again:

    Start to implement a built-in version of `git add --interactive`

    Unlike previous conversions to C, where we started with a built-in
    helper, we start this conversion by adding an interception in the
    `run_add_interactive()` function when the new opt-in
    `add.interactive.useBuiltin` config knob is turned on (or the
    corresponding environment variable `GIT_TEST_ADD_I_USE_BUILTIN`), and
    calling the new internal API function `run_add_i()` that is implemented
    directly in libgit.a.

    At this point, the built-in version of `git add -i` only states that it
    cannot do anything yet. In subsequent patches/patch series, the
    `run_add_i()` function will gain more and more functionality, until it
    is feature complete. The whole arc of the conversion can be found in the
    PRs #170-175 at https://github.com/gitgitgadget/git.

    The "--helper approach" can unfortunately not be used here: on Windows
    we face the very specific problem that a `system()` call in
    Perl seems to close `stdin` in the parent process when the spawned
    process consumes even one character from `stdin`. Which prevents us from
    implementing the main loop in C and still trying to hand off to the Perl
    script.

    The very real downside of the approach we have to take here is that the
    test suite won't pass with `GIT_TEST_ADD_I_USE_BUILTIN=true` until the
    conversion is complete (the `--helper` approach would have let it pass,
    even at each of the incremental conversion steps).

Any suggestions how to improve that commit message?

Ciao,
Dscho

  reply	other threads:[~2019-11-11  9:15 UTC|newest]

Thread overview: 124+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-10 17:37 [PATCH 00/11] git add -i: add a rudimentary version in C (supporting only status and help so far) Johannes Schindelin via GitGitGadget
2019-04-10 17:37 ` [PATCH 01/11] Start to implement a built-in version of `git add --interactive` Johannes Schindelin via GitGitGadget
2019-04-18 14:31   ` Jeff Hostetler
2019-04-18 16:06     ` Jeff King
2019-04-30 23:40       ` Johannes Schindelin
2019-05-01  2:21         ` Jeff King
2019-05-13 11:14           ` Johannes Schindelin
2019-04-10 17:37 ` [PATCH 02/11] diff: export diffstat interface Daniel Ferreira via GitGitGadget
2019-04-10 17:37 ` [PATCH 03/11] built-in add -i: implement the `status` command Daniel Ferreira via GitGitGadget
2019-04-10 17:37 ` [PATCH 04/11] built-in add -i: refresh the index before running `status` Johannes Schindelin via GitGitGadget
2019-04-10 17:37 ` [PATCH 05/11] built-in add -i: color the header in the `status` command Johannes Schindelin via GitGitGadget
2019-04-10 17:37 ` [PATCH 06/11] built-in add -i: implement the main loop Johannes Schindelin via GitGitGadget
2019-04-18 16:49   ` Jeff Hostetler
2019-05-13 12:04     ` Johannes Schindelin
2019-04-10 17:37 ` [PATCH 07/11] Add a function to determine unique prefixes for a list of strings Slavica Djukic via GitGitGadget
2019-04-18 17:57   ` Jeff Hostetler
2019-05-13 12:48     ` Johannes Schindelin
2019-04-10 17:37 ` [PATCH 08/11] built-in add -i: show unique prefixes of the commands Slavica Djukic via GitGitGadget
2019-04-10 17:37 ` [PATCH 09/11] built-in add -i: support `?` (prompt help) Johannes Schindelin via GitGitGadget
2019-04-10 17:37 ` [PATCH 10/11] built-in add -i: use color in the main loop Slavica Djukic via GitGitGadget
2019-04-10 17:37 ` [PATCH 11/11] built-in add -i: implement the `help` command Johannes Schindelin via GitGitGadget
2019-05-13 17:27 ` [PATCH v2 00/11] git add -i: add a rudimentary version in C (supporting only status and help so far) Johannes Schindelin via GitGitGadget
2019-05-13 17:27   ` [PATCH v2 01/11] Start to implement a built-in version of `git add --interactive` Johannes Schindelin via GitGitGadget
2019-05-13 17:27   ` [PATCH v2 02/11] diff: export diffstat interface Daniel Ferreira via GitGitGadget
2019-05-13 17:27   ` [PATCH v2 03/11] built-in add -i: implement the `status` command Daniel Ferreira via GitGitGadget
2019-05-13 17:27   ` [PATCH v2 04/11] built-in add -i: refresh the index before running `status` Johannes Schindelin via GitGitGadget
2019-05-13 17:27   ` [PATCH v2 06/11] built-in add -i: implement the main loop Johannes Schindelin via GitGitGadget
2019-05-13 17:27   ` [PATCH v2 05/11] built-in add -i: color the header in the `status` command Johannes Schindelin via GitGitGadget
2019-05-13 17:27   ` [PATCH v2 07/11] Add a function to determine unique prefixes for a list of strings Slavica Djukic via GitGitGadget
2019-05-13 17:27   ` [PATCH v2 08/11] built-in add -i: show unique prefixes of the commands Slavica Djukic via GitGitGadget
2019-05-13 17:28   ` [PATCH v2 09/11] built-in add -i: support `?` (prompt help) Johannes Schindelin via GitGitGadget
2019-05-13 17:28   ` [PATCH v2 10/11] built-in add -i: use color in the main loop Slavica Djukic via GitGitGadget
2019-05-13 17:28   ` [PATCH v2 11/11] built-in add -i: implement the `help` command Johannes Schindelin via GitGitGadget
2019-07-16 14:58   ` [PATCH v3 00/11] git add -i: add a rudimentary version in C (supporting only status and help so far) Johannes Schindelin via GitGitGadget
2019-07-16 14:58     ` [PATCH v3 01/11] Start to implement a built-in version of `git add --interactive` Johannes Schindelin via GitGitGadget
2019-07-31 17:52       ` Junio C Hamano
2019-08-26 21:26         ` Johannes Schindelin
2019-08-27 22:25           ` Junio C Hamano
2019-08-28 15:06             ` Johannes Schindelin
2019-08-28 15:37               ` Junio C Hamano
2019-07-16 14:58     ` [PATCH v3 02/11] diff: export diffstat interface Daniel Ferreira via GitGitGadget
2019-07-31 17:59       ` Junio C Hamano
2019-08-27  9:22         ` Johannes Schindelin
2019-07-16 14:58     ` [PATCH v3 03/11] built-in add -i: implement the `status` command Daniel Ferreira via GitGitGadget
2019-07-31 18:12       ` Junio C Hamano
2019-08-27 10:04         ` Johannes Schindelin
2019-07-16 14:58     ` [PATCH v3 04/11] built-in add -i: refresh the index before running `status` Johannes Schindelin via GitGitGadget
2019-07-16 14:58     ` [PATCH v3 05/11] built-in add -i: color the header in the `status` command Johannes Schindelin via GitGitGadget
2019-07-16 14:58     ` [PATCH v3 06/11] built-in add -i: implement the main loop Johannes Schindelin via GitGitGadget
2019-07-31 18:14       ` Junio C Hamano
2019-07-16 14:58     ` [PATCH v3 07/11] Add a function to determine unique prefixes for a list of strings Slavica Djukic via GitGitGadget
2019-07-31 18:39       ` Junio C Hamano
2019-08-24 12:38       ` SZEDER Gábor
2019-08-27 12:14         ` Johannes Schindelin
2019-08-28 16:30           ` SZEDER Gábor
2019-08-28 16:34             ` [PATCH] [PoC] A simpler find_unique_prefixes() implementation SZEDER Gábor
2019-08-30 20:12               ` Johannes Schindelin
2019-07-16 14:58     ` [PATCH v3 08/11] built-in add -i: show unique prefixes of the commands Slavica Djukic via GitGitGadget
2019-07-16 14:58     ` [PATCH v3 09/11] built-in add -i: support `?` (prompt help) Johannes Schindelin via GitGitGadget
2019-07-16 14:58     ` [PATCH v3 10/11] built-in add -i: use color in the main loop Slavica Djukic via GitGitGadget
2019-07-16 14:58     ` [PATCH v3 11/11] built-in add -i: implement the `help` command Johannes Schindelin via GitGitGadget
2019-08-02 21:04       ` Junio C Hamano
2019-08-02 22:26         ` Jeff King
2019-07-16 18:38     ` [PATCH v3 00/11] git add -i: add a rudimentary version in C (supporting only status and help so far) Johannes Schindelin
2019-08-02 21:06       ` Junio C Hamano
2019-08-27 12:57     ` [PATCH v4 " Johannes Schindelin via GitGitGadget
2019-08-27 12:57       ` [PATCH v4 01/11] Start to implement a built-in version of `git add --interactive` Johannes Schindelin via GitGitGadget
2019-08-27 12:57       ` [PATCH v4 02/11] diff: export diffstat interface Daniel Ferreira via GitGitGadget
2019-08-27 12:57       ` [PATCH v4 03/11] built-in add -i: implement the `status` command Daniel Ferreira via GitGitGadget
2019-08-27 12:57       ` [PATCH v4 04/11] built-in add -i: refresh the index before running `status` Johannes Schindelin via GitGitGadget
2019-08-27 12:57       ` [PATCH v4 05/11] built-in add -i: color the header in the `status` command Johannes Schindelin via GitGitGadget
2019-08-27 12:57       ` [PATCH v4 06/11] built-in add -i: implement the main loop Johannes Schindelin via GitGitGadget
2019-08-27 12:57       ` [PATCH v4 07/11] Add a function to determine unique prefixes for a list of strings Slavica Djukic via GitGitGadget
2019-08-27 12:57       ` [PATCH v4 08/11] built-in add -i: show unique prefixes of the commands Slavica Djukic via GitGitGadget
2019-08-27 12:58       ` [PATCH v4 09/11] built-in add -i: support `?` (prompt help) Johannes Schindelin via GitGitGadget
2019-08-27 12:58       ` [PATCH v4 10/11] built-in add -i: use color in the main loop Slavica Djukic via GitGitGadget
2019-08-27 12:58       ` [PATCH v4 11/11] built-in add -i: implement the `help` command Johannes Schindelin via GitGitGadget
2019-11-04 12:15       ` [PATCH v5 0/9] git add -i: add a rudimentary version in C (supporting only status and help so far) Johannes Schindelin via GitGitGadget
2019-11-04 12:15         ` [PATCH v5 1/9] Start to implement a built-in version of `git add --interactive` Johannes Schindelin via GitGitGadget
2019-11-08  4:49           ` Junio C Hamano
2019-11-09 11:06             ` Johannes Schindelin
2019-11-10  7:18               ` Junio C Hamano
2019-11-11  9:15                 ` Johannes Schindelin [this message]
2019-11-11 12:09                   ` Junio C Hamano
2019-11-12 15:03                     ` Johannes Schindelin
2019-11-13  3:54                       ` Junio C Hamano
2019-11-13 12:30                         ` Johannes Schindelin
2019-11-13 14:01                           ` Junio C Hamano
2019-11-04 12:15         ` [PATCH v5 2/9] diff: export diffstat interface Daniel Ferreira via GitGitGadget
2019-11-08  4:56           ` Junio C Hamano
2019-11-04 12:15         ` [PATCH v5 3/9] built-in add -i: implement the `status` command Daniel Ferreira via GitGitGadget
2019-11-08  5:01           ` Junio C Hamano
2019-11-04 12:15         ` [PATCH v5 4/9] built-in add -i: color the header in " Slavica Đukić via GitGitGadget
2019-11-04 12:15         ` [PATCH v5 5/9] built-in add -i: implement the main loop Johannes Schindelin via GitGitGadget
2019-11-08  5:17           ` Junio C Hamano
2019-11-09 11:21             ` Johannes Schindelin
2019-11-04 12:15         ` [PATCH v5 6/9] built-in add -i: show unique prefixes of the commands Johannes Schindelin via GitGitGadget
2019-11-04 12:15         ` [PATCH v5 7/9] built-in add -i: support `?` (prompt help) Johannes Schindelin via GitGitGadget
2019-11-04 12:15         ` [PATCH v5 8/9] built-in add -i: use color in the main loop Slavica Đukić via GitGitGadget
2019-11-04 12:15         ` [PATCH v5 9/9] built-in add -i: implement the `help` command Slavica Đukić via GitGitGadget
2019-11-13 12:40         ` [PATCH v6 0/9] git add -i: add a rudimentary version in C (supporting only status and help so far) Johannes Schindelin via GitGitGadget
2019-11-13 12:40           ` [PATCH v6 1/9] Start to implement a built-in version of `git add --interactive` Johannes Schindelin via GitGitGadget
2019-11-14  2:15             ` Junio C Hamano
2019-11-14 15:07               ` Johannes Schindelin
2019-11-15  4:35                 ` Junio C Hamano
2019-11-13 12:40           ` [PATCH v6 2/9] diff: export diffstat interface Daniel Ferreira via GitGitGadget
2019-11-13 12:40           ` [PATCH v6 3/9] built-in add -i: implement the `status` command Daniel Ferreira via GitGitGadget
2019-11-13 12:41           ` [PATCH v6 4/9] built-in add -i: color the header in " Slavica Đukić via GitGitGadget
2019-11-13 12:41           ` [PATCH v6 5/9] built-in add -i: implement the main loop Johannes Schindelin via GitGitGadget
2019-11-13 12:41           ` [PATCH v6 6/9] built-in add -i: show unique prefixes of the commands Johannes Schindelin via GitGitGadget
2019-11-13 12:41           ` [PATCH v6 7/9] built-in add -i: support `?` (prompt help) Johannes Schindelin via GitGitGadget
2019-11-13 12:41           ` [PATCH v6 8/9] built-in add -i: use color in the main loop Slavica Đukić via GitGitGadget
2019-11-13 12:41           ` [PATCH v6 9/9] built-in add -i: implement the `help` command Slavica Đukić via GitGitGadget
2019-11-13 12:46           ` [PATCH v6 0/9] git add -i: add a rudimentary version in C (supporting only status and help so far) Johannes Schindelin
2019-11-15 11:11           ` [PATCH v7 " Johannes Schindelin via GitGitGadget
2019-11-15 11:11             ` [PATCH v7 1/9] Start to implement a built-in version of `git add --interactive` Johannes Schindelin via GitGitGadget
2019-11-15 11:11             ` [PATCH v7 2/9] diff: export diffstat interface Daniel Ferreira via GitGitGadget
2019-11-15 11:11             ` [PATCH v7 3/9] built-in add -i: implement the `status` command Daniel Ferreira via GitGitGadget
2019-11-15 11:11             ` [PATCH v7 4/9] built-in add -i: color the header in " Slavica Đukić via GitGitGadget
2019-11-15 11:11             ` [PATCH v7 5/9] built-in add -i: implement the main loop Johannes Schindelin via GitGitGadget
2019-11-15 11:11             ` [PATCH v7 6/9] built-in add -i: show unique prefixes of the commands Johannes Schindelin via GitGitGadget
2019-11-15 11:11             ` [PATCH v7 7/9] built-in add -i: support `?` (prompt help) Johannes Schindelin via GitGitGadget
2019-11-15 11:11             ` [PATCH v7 8/9] built-in add -i: use color in the main loop Slavica Đukić via GitGitGadget
2019-11-15 11:11             ` [PATCH v7 9/9] built-in add -i: implement the `help` command Slavica Đukić via GitGitGadget

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=nycvar.QRO.7.76.6.1911110949590.46@tvgsbejvaqbjf.bet \
    --to=johannes.schindelin@gmx.de \
    --cc=git@jeffhostetler.com \
    --cc=git@vger.kernel.org \
    --cc=gitgitgadget@gmail.com \
    --cc=gitster@pobox.com \
    --cc=peff@peff.net \
    --subject='Re: [PATCH v5 1/9] Start to implement a built-in version of `git add --interactive`' \
    /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

git@vger.kernel.org list mirror (unofficial, one of many)

This inbox may be cloned and mirrored by anyone:

	git clone --mirror https://public-inbox.org/git
	git clone --mirror http://ou63pmih66umazou.onion/git
	git clone --mirror http://czquwvybam4bgbro.onion/git
	git clone --mirror http://hjrcffqmbrq6wope.onion/git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V1 git git/ https://public-inbox.org/git \
		git@vger.kernel.org
	public-inbox-index git

Example config snippet for mirrors.
Newsgroups are available over NNTP:
	nntp://news.public-inbox.org/inbox.comp.version-control.git
	nntp://7fh6tueqddpjyxjmgtdiueylzoqt6pt7hec3pukyptlmohoowvhde4yd.onion/inbox.comp.version-control.git
	nntp://ie5yzdi7fg72h7s4sdcztq5evakq23rdt33mfyfcddc5u3ndnw24ogqd.onion/inbox.comp.version-control.git
	nntp://4uok3hntl7oi7b4uf4rtfwefqeexfzil2w6kgk2jn5z2f764irre7byd.onion/inbox.comp.version-control.git
	nntp://news.gmane.io/gmane.comp.version-control.git
 note: .onion URLs require Tor: https://www.torproject.org/

code repositories for project(s) associated with this inbox:

	https://80x24.org/mirrors/git.git

AGPL code for this site: git clone https://public-inbox.org/public-inbox.git