Subject: Re: [PATCH] cache-tree: populate cache-tree on successful merge

From: Junio C Hamano <[email-masked]>
Date: Tue, 28 Jul 2015 14:38:18 -0700

David Turner <[email-masked]> writes:

> On Tue, 2015-07-28 at 13:47 -0700, Junio C Hamano wrote:
>> David Turner <[email-masked]> writes:
>> 
>> > When we unpack trees into an existing index, we discard the old index
>> > and replace it with the new, merged index.  Ensure that this index has
>> > its cache-tree populated.  This will make subsequent git status and
>> > commit commands faster.
>> >
>> > Signed-off-by: David Turner <[email-masked]>
>> > Signed-off-by: Brian Degenhardt <[email-masked]>
>> > ---
>> >
>> > This patch is by my colleague, Brian Degenhardt (as part of his work
>> > on git at Twitter).  I'm sending it with his and Twitter's approval.
>> 
>> I'd need to tweak the From:/Author: line then, and flip the order of
>> the sign-off, as Brian wrote and signed off then David relayed (as
>> attached).
>
> Where do I put an Author: line? In the commit message above the
> signoffs?  As an email header?  I didn't see an option to git send-email
> that would do this.  I don't want to use the From: header because I want
> to be the point-of-contact for these patches.

The message you are responding to would have been a good example of
forcing the author, subject and author-date to be different from the
e-mail headers.  That is, if you did "git am -s -c" on my message
you responded to, you would have seen a new commit authored by
Brian; and anybody responding to the message would have sent that
e-mail to me (and [email-masked]).

I think that is the arrangement you are looking for.

Delete everything before and including the "-- >8 --" line from my
message you responded to and then the person who applies does not
have to say "-c" but just with "git am -s" the same thing would have
happened.  E-mail coming from (and reply going to) you, but resulting
commit would be authored by Brian.

"git send-email", if you are sending somebody else's commit, should
automatically add the in-body header "From: Brian ..." as the first
line of the body, with a blank line and the body of the commit log.

>> By the way, I wonder if we can lose/revert aecf567c (cache-tree:
>> create/update cache-tree on checkout, 2014-07-05), now the
>> underlying unpack_trees() does the necessary cache_tree_update()
>> when a branch is checked out.
>
> Well, the tests still pass, so I guess so. That is, we still need the
> WRITE_TREE_REPAIR bit, but not the update check.
>
> Will re-roll once I hear back on the author line.

Let's not do the "drop cache-tree generation from checkout" in the
same patch.  It can be done as a separate patch but I do not think
it is a very high priority.

With that understanding, what I have received from you (with a minor
tweak shown in the message you are responding to) is already fine, I
think.

Thanks.