From: Junio C Hamano <gitster@pobox.com>
Date: Tue, 08 Dec 2015 18:18:28 GMT
Subject: Re: [PATCH 2/2] format-patch: add an option to suppress commit hash
Message-ID: <xmqqa8pkls7f.fsf@gitster.mtv.corp.google.com>
In-Reply-To: <20151208010227.GC990758@vauxhall.crustytoothpaste.net>

"brian m. carlson" <sandals@crustytoothpaste.net> writes:

>> Don't test "any number of '0'"; test 40 '0's.  This is because the
>> line format was designed to be usable by things like /etc/magic to
>> detect format-patch output, and we want to notice if/when we break
>> that aspect of our output format.
>
> My idea was to future-proof it against changes in the hash function,
> although that's in the distant future.

Making sure that the test fails when somebody accidentally lengthens
(or fails to truncate to 40-hex, when you start using a longer hash)
the displayed name there is a good future-proofing.

Thanks.