Re: [PATCH 0/2] fixing parse_object() check for type mismatch

> On Fri, Nov 18, 2022 at 02:05:04PM -0500, Taylor Blau wrote:
>
>> On Thu, Nov 17, 2022 at 05:37:29PM -0500, Jeff King wrote:
>> > I'm adding Taylor to the cc as the author of t6102, when we were
>> > tracking down all of these "oops, it's not really a blob" cases. This
>> > fixes one of the lingering cases from that test script.
>> >
>> >   [1/2]: parse_object(): drop extra "has" check before checking object type
>> >   [2/2]: parse_object(): check on-disk type of suspected blob
>> >
>> >  object.c                               | 5 ++---
>> >  t/t6102-rev-list-unexpected-objects.sh | 4 ++--
>> >  2 files changed, 4 insertions(+), 5 deletions(-)
>> 
>> A blast from the past :-).
>> 
>> I took a careful look at both of these patches and they looked good to
>> me, so let's start merging them down.
>
> I saw this hit 'next', but I think Ævar's simplification suggestion is
> worth taking. So here is a patch on top to do so (the original branch is
> jk/parse-object-type-mismatch for the benefit of any newly-returned
> maintainers).
>
> I was going to do a "helped-by", but since the only thing in the patch
> is the suggested change, I just handed over authorship. :)
>
> I didn't forge a signoff, and I think mine is sufficient under DCO's
> part (b), but Ævar please indicate if that's OK.

> -- >8 --
> From: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
> Subject: [PATCH] parse_object(): simplify blob conditional
>
> Commit 8db2dad7a0 (parse_object(): check on-disk type of suspected blob,
> 2022-11-17) simplified the conditional for checking if we might have a
> blob. But we can simplify it further. In:
>
>   !obj || (obj && obj->type == OBJ_BLOB)
>
> the short-circuit "OR" means "obj" will always be true on the right-hand
> side. The compiler almost certainly optimized that out anyway, but
> dropping it makes the conditional easier to understand for humans.
>
> Signed-off-by: Jeff King <peff@peff.net>
> ---
>  object.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/object.c b/object.c
> index fad1a5af4a..682b852a46 100644
> --- a/object.c
> +++ b/object.c
> @@ -286,7 +286,7 @@ struct object *parse_object_with_flags(struct repository *r,
>  			return &commit->object;
>  	}
>  
> -	if ((!obj || (obj && obj->type == OBJ_BLOB)) &&
> +	if ((!obj || obj->type == OBJ_BLOB) &&
>  	    oid_object_info(r, oid, NULL) == OBJ_BLOB) {
>  		if (!skip_hash && stream_object_signature(r, repl) < 0) {
>  			error(_("hash mismatch %s"), oid_to_hex(oid));