Hi Martin,
Thanks for your review! Your comments were all quite helpful, and I
applied all of your suggested changes.
On Fri, Jan 31, 2020 at 07:52:02AM +0100, Martin Ågren wrote:
> On Fri, 31 Jan 2020 at 00:03, Taylor Blau <me@xxxxxxxxxxxx> wrote:
> > Instead of getting rid of the 'struct object_directory *', store that
> > insead of a 'char *odb' in 'struct commit_graph'. Once the 'struct
>
> s/insead/instead/
Typo. Thanks for noticing. I fixed this in my local copy of this branch.
> > if (open_ok)
> > graph = load_commit_graph_one_fd_st(fd, &st);
> > - else
> > - graph = read_commit_graph_one(the_repository, opts.obj_dir);
> > + else {
> > + struct object_directory *odb;
> > + if ((odb = find_odb(the_repository, opts.obj_dir)))
> > + graph = read_commit_graph_one(the_repository, odb);
> > + }
>
> I'm a tiny bit allergic to this assignment-within-if. It's wrapped by
> another pair of parentheses, which both compilers and humans know to
> interpret as "trust me, this is not a mistake", but I still find this
> easier to read:
>
> odb = find_odb(...);
> if (odb)
> ....
To be honest, I'm not such a fan of this style myself, but it seemed odd
to me to write:
struct object_directory *odb;
odb = ...;
if (odb) {
}
when we were really only trying to call 'find_odb()' and do something
with its result, but only if it was non-NULL. I counted 152 of these
assign-if's laying around with:
$ git grep 'if ((.* =[^=]' | wc -l
but it seems like they are in poor style (as evidenced by your and
Junio's response later in the thread). So, I removed this and instead
promoted 'odb' to a local variable at the function level, since we
do that promotion anyway in a couple of patches later. This reduces the
churn, and avoids either an assign-if, or a define/assign/check.
> > --- a/builtin/commit.c
> > +++ b/builtin/commit.c
>
> > +#include "object-store.h"
No; this is a stray left over from some development on this branch. I'll
remove it.
> This is the only change in this file, which looks a bit odd. I haven't
> actually applied your patches, to be honest, but is this inclusion
> really needed?
>
> > --- a/commit-graph.c
> > +++ b/commit-graph.c
>
> > +struct object_directory *find_odb(struct repository *r, const char *obj_dir)
>
> This doesn't look commit-graph related -- could/should it go somewhere
> else?
I'll respond in more complete detail further down in the thread, but the
short answer is "yes, this should go in builtin/commit-graph.c".
> > +{
> > + struct object_directory *odb;
> > + char *obj_dir_real = real_pathdup(obj_dir, 1);
> > + int cmp = -1;
> > +
> > + prepare_alt_odb(r);
> > + for (odb = r->objects->odb; odb; odb = odb->next) {
> > + cmp = strcmp(obj_dir_real, real_path(odb->path));
> > + if (!cmp)
> > + break;
> > + }
>
> At this point, either odb is NULL or cmp is zero. Those are the only two
> ways out of the loop.
>
> > + free(obj_dir_real);
> > +
> > + if (cmp)
> > + odb = NULL;
>
> Meaning that this doesn't do much? If the most recent comparison failed,
> it's because we didn't find anything, so odb will be NULL.
>
> > + return odb;
> > +}
>
> I think you could drop `cmp` and that final check, and write the loop
> body as "if (!strcmp(...)) break". You could also have an empty loop
> body, but I wouldn't go there -- I'd find that less readable. (Maybe
> that's just me.)
Thanks, I changed this to remove the 'cmp' check outside of the loop,
which I agree is unnecessary.
> Martin
Thanks,
Taylor
