Re: [PATCH v2] merge-options.txt: clarify meaning of various ff-related options

From: Martin Ågren <martin.agren@gmail.com>
Date: Aug 28, 2019, 19:53 UTC
Message-ID: <CAN0heSpcFgNwBKHzUjcvb0W46LQwGoOSpihLg1arOPJJKC9PTQ@mail.gmail.com>
In-Reply-To: <87a7btqeyx.fsf@osv.gnss.ru>

Hiya,

On Wed, 28 Aug 2019 at 21:15, Sergey Organov <sorganov@gmail.com> wrote:

Show 8 quoted lines

> > I was sort of expecting these to be listed in the order "--ff, --no-ff,
> > --ff-only", and I see Sergey suggested the same ordering. The way your
> > proposed text reads does make sense though... Would it read as well
> > turning it over and going through the options in the other order? That's
> > the way it is before your patch, so you could argue "but people don't
> > grok that!". What your patch does well is to offer an overview before
> > describing each option in a bit more detail. Would that work with the
> > reversed direction as well (compared to this patch)? Dunno.

Show 19 quoted lines

> Dunno if it helps, but here is what I came up with somewhere in previous
> discussions:
>
> --ff::
> --no-ff::
> --ff-only::
>         When the merge resolves as a fast-forward, only update the
>         branch pointer (without creating a merge commit).  When a fast
>         forward update is not possible, create a merge commit.  This is
>         the default behavior, unless merging an annotated (and possibly
>         signed) tag that is not stored in its natural place in
>         'refs/tags/' hierarchy, in which case --no-ff is assumed.
> +
> With --no-ff create a merge commit even when the merge could instead
> resolve as a fast-forward.
> +
> With --ff-only resolve the merge as a fast-forward (never create a merge
> commit). When fast-forward is not possible, refuse to merge and exit
> with non-zero status.

I think this could make clear that the first paragraph talks about `--ff`. I know that we often list `--foo` and `--no-foo`, say "This option does bar" and leave it to the reader to figure out which is which. Most of the time, that's fairly obvious though (foo=bar). With this tri-state option, we might be past the point of fair obviousness. Then again, seeing "ff" and "fast forward", it's not /that hard/ to figure out.

Apart from that, this reads well. Of course with the usual caveat of the topic being fresh on my mind, so in general, I'd be more likely to understand what it is I'm reading. ;-)

Martin