Re: [RFC PATCH 1/9] rebase -i: only write fixup-message when it's needed

>
> Hi Taylor and Charvi
>
> On 14/01/2021 08:12, Charvi Mendiratta wrote:
> > On Thu, 14 Jan 2021 at 00:13, Taylor Blau <me@ttaylorr.com> wrote:
> >>
> >> On Fri, Jan 08, 2021 at 02:53:39PM +0530, Charvi Mendiratta wrote:
> >>> From: Phillip Wood <phillip.wood@dunelm.org.uk>
> >>>
> >>> The file "$GIT_DIR/rebase-merge/fixup-message" is only used for fixup
> >>> commands, there's no point in writing it for squash commands as it is
> >>> immediately deleted.
> >>>
> >>> Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
> >>> Signed-off-by: Charvi Mendiratta <charvi077@gmail.com>
> >>> ---
> >>>   sequencer.c | 12 +++++++-----
> >>>   1 file changed, 7 insertions(+), 5 deletions(-)
> >>>
> >>> diff --git a/sequencer.c b/sequencer.c
> >>> index 8909a46770..f888a7ed3b 100644
> >>> --- a/sequencer.c
> >>> +++ b/sequencer.c
> >>> @@ -1757,11 +1757,13 @@ static int update_squash_messages(struct repository *r,
> >>>                        return error(_("could not read HEAD's commit message"));
> >>>
> >>>                find_commit_subject(head_message, &body);
> >>> -             if (write_message(body, strlen(body),
> >>> -                               rebase_path_fixup_msg(), 0)) {
> >>> -                     unuse_commit_buffer(head_commit, head_message);
> >>> -                     return error(_("cannot write '%s'"),
> >>> -                                  rebase_path_fixup_msg());
> >>> +             if (command == TODO_FIXUP) {
> >>> +                     if (write_message(body, strlen(body),
> >>> +                                       rebase_path_fixup_msg(), 0)) {
> >>> +                             unuse_commit_buffer(head_commit, head_message);
> >>> +                             return error(_("cannot write '%s'"),
> >>> +                                          rebase_path_fixup_msg());
> >>> +                     }
> >>
> >> I'm nit-picking here, but would this be clearer instead as:
> >>
> >>      if (command == TODO_FIXUP && write_message(...) < 0) {
> >>        unuse_commit_buffer(...);
> >>        // ...
> >>      }
> >>
> >> There are two changes there. One is two squash the two if-statements
> >> together, and the latter is to add a check that 'write_message()'
> >> returns an error. This explicit '< 0' checking was discussed recently in
> >> another thread[1], and I think makes the conditional here read more
> >> clearly.
>
> I don't feel that strongly but the addition of '< 0' feels like it is
> adding an unrelated change to this commit. It also leaves a code base
> where most callers of `write_message()` do not check the sign of the
> return value but a couple do (there appears to be one that checks the
> sign already and a couple that completely ignore the return value). If
> we want to standardize on always checking the sign of the return value
> of functions when checking for errors even when they never return a
> positive value then I think someone in favor of that change should
> propose a patch to the coding guidelines so it is clear what our policy
> is. When I see a '< 0`' check I tend to think the positive value has a
> non-error meaning.
>

> Best Wishes
>
> Phillip
>
> > Okay, I got this and will change it.
> >
> > Thanks and Regards,
> > Charvi
> >
> >> Thanks,
> >> Taylor
> >>
> >> [1]: https://lore.kernel.org/git/xmqqlfcz8ggj.fsf@gitster.c.googlers.com/
>