Re: obsolete index in wt_status_print after pre-commit hook runs

From: Junio C Hamano <gitster@pobox.com>
Date: Jul 15, 2016, 22:03 UTC
Message-ID: <xmqqh9bqlfto.fsf@gitster.mtv.corp.google.com>
In-Reply-To: <CAPc5daWZofdZnE0VQyFX2sBQyEDvAPmU+4rmHe5rvh7eH001ZA@mail.gmail.com>

Junio C Hamano <gitster@pobox.com> writes:

Show 12 quoted lines

> On Fri, Jul 15, 2016 at 1:30 PM, Andrew Keller <andrew@kellerfarm.com> wrote:
>> Am 15.07.2016 um 12:34 nachm. schrieb Andrew Keller <andrew@kellerfarm.com>:
>>
>>> I pulled out the source for version 2.9.1 and briefly skimmed how run_commit and
>>> prepare_to_commit work.  It seems that Git already understands that a pre-commit
>>> hook can change the index, and it rereads the index before running the
>>> prepare-commit-msg hook: https://github.com/git/git/blob/v2.9.1/builtin/commit.c#L941-L951
>>
>> Quick question: Why does Git reread the index after the pre-commit hook runs?
>
> Offhand I do not think of a good reason to do so; does something break
> if you took it out?

Ahh, I misremembered. 2888605c (builtin-commit: fix partial-commit support, 2007-11-18) does consider the possibility that pre-commit may have modified the index contents after we take control back from that hook, so that is probably a good place to enumerate what got changed. Getting the list before running the hook can give an out-of-date list, as you said.

Thanks.