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

>
> 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.
>