Re: [PATCH v2] read-cache: write all indexes with the same permissions

From: Junio C Hamano <gitster@pobox.com>
To: Christian Couder <christian.couder@gmail.com>
Cc: "SZEDER Gábor" <szeder.dev@gmail.com>, git <git@vger.kernel.org>,
	"Jeff King" <peff@peff.net>,
	"Nguyen Thai Ngoc Duy" <pclouds@gmail.com>,
	"Michael Haggerty" <mhagger@alum.mit.edu>,
	"Ævar Arnfjörð Bjarmason" <avarab@gmail.com>,
	"Christian Couder" <chriscool@tuxfamily.org>
Subject: Re: [PATCH v2] read-cache: write all indexes with the same permissions
Date: Sat, 17 Nov 2018 17:57:18 +0900	[thread overview]
Message-ID: <xmqqy39sgjyp.fsf@gitster-ct.c.googlers.com> (raw)
In-Reply-To: <CAP8UFD2tC9B_m=NmK4DTCJP=o+L+RKy9C_2ra9fgeNMzOuCZ3A@mail.gmail.com> (Christian Couder's message of "Fri, 16 Nov 2018 20:25:43 +0100")

Christian Couder <christian.couder@gmail.com> writes:

>> > +test_expect_success POSIXPERM 'same mode for index & split index' '
>> > +     git init same-mode &&
>> > +     (
>> > +             cd same-mode &&
>> > +             test_commit A &&
>> > +             test_modebits .git/index >index_mode &&
>> > +             test_must_fail git config core.sharedRepository &&
>> > +             git -c core.splitIndex=true status &&
>> > +             shared=$(ls .git/sharedindex.*) &&
>>
>> I think the command substitution and 'ls' are unnecessary, and
>>
>>   shared=.git/sharedindex.*
>>
>> would work as well.
>
> If there is no shared index file with the above we would get:
>
> shared=.git/sharedindex.*
> $ echo $shared
> .git/sharedindex.*
>
> which seems bug prone to me.

It is not bug *PRONE*, but is already wrong, as the way this
variable is used is

        +		case "$shared" in
        +		*" "*)
        +			# we have more than one???
        +			false ;;
        +		*)
        +			test_modebits "$shared" >split_index_mode &&
        +			test_cmp index_mode split_index_mode ;;
        +		esac

i.e. we'd think there is a singleton ".git/shared/index.*" and we
can feed it to test_modebits.

So what you wrote originally is corrrect.