Re: RFE: support change-id generation natively

From: Shawn Pearce <spearce@spearce.org>
Date: Oct 21, 2013, 23:10 UTC
Message-ID: <CAJo=hJsEHO7ZL6UBbBBijRNHqk=ttA07cFJ7KBW381jTEpvOQw@mail.gmail.com>
In-Reply-To: <1382380858.25852.36711509.53CF173C@webmail.messagingengine.com>

On Mon, Oct 21, 2013 at 11:40 AM,  <james.moger@gitblit.com> wrote:

Show 10 quoted lines

>
> On Mon, Oct 21, 2013, at 02:29 PM, Thomas Koch wrote:
>> As I understand, a UUID could also be used for the same purbose as the
>> change-
>> id. How is the change-id generated by the way? Would it be a good english
>> name
>> to call it enduring commit identifier?
>
> Here is the algorithm:
> https://git.eclipse.org/c/jgit/jgit.git/tree/org.eclipse.jgit/src/org/eclipse/jgit/util/ChangeIdUtil.java#n78

For the hyperlink and Java challenged, the Change-Id is essentially the commit SHA-1 had the Change-Id not been included. The shell script hook Gerrit recommends for use with `git commit` uses `git commit-tree` to compute the hash. Which of course later differs after the Change-Id is inserted.

> I think "enduring commit id" is a fair interpretation of it's purpose.
> I don't speak for the Gerrit developers so I can not say if they are
> interested in alternative id generation.  I come to the list as a
> change-id user/consumer.

As Martin Fick said, we would be open to an alternative if a better one is presented, especially if it is supported by git commit.