Re: [PATCH RFC] rebase: respect --ff-only option

From: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date: Jul 6, 2021, 14:43 UTC
Message-ID: <87mtqz5wb2.fsf@evledraar.gmail.com>
In-Reply-To: <CAMMLpeQG-eYgWTXyG0YzgN3U8QDASAtNFpxyXDFFPSVNzfw18g@mail.gmail.com>

On Mon, Jul 05 2021, Alex Henrie wrote:

Show 27 quoted lines

> On Mon, Jul 5, 2021 at 3:36 AM Ævar Arnfjörð Bjarmason <avarab@gmail.com> wrote:
>>
>> On Sun, Jul 04 2021, Alex Henrie wrote:
>>
>> > +int error_ff_impossible(void)
>> > +{
>> > +     error(_("Not possible to fast-forward, aborting."));
>> > +     return -1;
>> > +}
>>
>> Here's one, the idiom is just "return error", i.e it itself returns -1.
>
> That would indeed be simpler; thanks for pointing that out.
>
>> FWIW I'd consider doing:
>>
>>         /* earlier, static scope */
>>         static const char error_ff_impossible = N_("Not possible...");
>>         /* later, function scope */
>>             return error(error_ff_impossible);
>>
>> It's a small difference, but for translators who use the jump-to-source
>> while translating not having the indirection helps, and in this case
>> it's just used 3 times...
>
> Wouldn't jump-to-source take the user to the English text in advice.c
> either way? How does putting it in a static variable help?

Yes, sorry. I don't know what I was thinking there. What I said would only apply if _() was used inline, nevermind.

Show 13 quoted lines

>> > [...]
>> >       if (parent && parse_commit(parent) < 0)
>> >               /* TRANSLATORS: The first %s will be a "todo" command like
>> > @@ -2764,7 +2769,7 @@ static int populate_opts_cb(const char *key, const char *value, void *data)
>> >       else if (!strcmp(key, "options.record-origin"))
>> >               opts->record_origin = git_config_bool_or_int(key, value, &error_flag);
>> >       else if (!strcmp(key, "options.allow-ff"))
>> > -             opts->allow_ff = git_config_bool_or_int(key, value, &error_flag);
>> > +             opts->fast_forward = git_config_bool_or_int(key, value, &error_flag) ? FF_ALLOW : FF_NO;
>>
>> Since we're on nits, we try to wrap at 80 characters.
>
> Thanks, I didn't know what the exact cutoff was.

It's not strictly adhered to, and depending on the code we'll have it be longer (sometimes much so) if it helps the general readability, e.g. long repetitive declarations or something. For this sort of thing it's generally preferred.

Show 22 quoted lines

> On Mon, Jul 5, 2021 at 10:50 AM Junio C Hamano <gitster@pobox.com> wrote:
>>
>> Phillip Wood <phillip.wood123@gmail.com> writes:
>>
>> > Looking at origin/seen:builtin/pull.c we already check if we can
>> > fast-forward and unconditionally merge in that case irrespective of
>> > any '--rebase' option or pull.rebase config. It should be simple for
>> > pull to error out if '--ff-only' is given and we cannot fast-forward.
>>
>> Excellent.
>>
>> Even though teaching even more special case on the "git pull" side
>> makes me feel somewhat dirty, but I think it would be a small price
>> to pay, and the end result would save an useless fork whose sole
>> purpose is to make the integration step after fetch fail when "pull"
>> can easily tell, as you said, that it ought to fail, so overall it
>> would probably be a net win.
>
> Okay, so it sounds like I should just scrap this patch and try again,
> after "pull: cleanup autostash check" is in master, with a patch that
> only modifies `git pull` and not `git rebase`. (Unless someone more
> experienced wants to take over, which would be fine by me.)

I've just skimmed that whole part of the larger "what should we do" discussion here, and don't really have an opinion, but I see Phillip Wood replied to this downthread.

You can grab the branches Junio mentions in What's Cooking from https://github.com/gitster/git.git, if you'd like to rebase on top of Felipe's (or from the ML).

And if you fetch from it with:

    fetch = +refs/notes/amlog:refs/notes/amlog

And set:

    [notes]
            displayRef = refs/notes/amlog

You'll get mappings from the mails to the commits Junio applies.

(Note that they're not always 1=1 the same, even after ignoring Junio's Signed-off-by header, he'll sometimes fix them up as he queues them, might use a different base for "master" than you did etc.)