Re: [RFC/PATCH] Add multiple workdir support to branch/checkout

[Nguyen Thai Ngoc Duy <pclouds@gmail.com>]

On Thu, Oct 6, 2011 at 3:46 AM, Junio C Hamano <gitster@pobox.com> wrote:
> Jay Soffian <jaysoffian@gmail.com> writes:
>
>> On Wed, Oct 5, 2011 at 12:02 AM, Nguyen Thai Ngoc Duy <pclouds@gmail.com> wrote:
>>> Could you please consider a more generic approach? What I have in mind
>>> is a mechanism to "lock" a branch, so that only commands that have the
>>> key can update it.
>>>
>>> So instead of branch.<name>.checkout, I would have something like
>>> branch.<name>.locked = <key>, where <key> is just a string. Only
>>> commands that provide the matching <key> are allowed to update the
>>> branch. In checkout case, <key> could be "checkout: worktree".
>>
>> In this case, each workdir needs its own key, so I'd have to record
>> the key somewhere, unless you meant using a key of "checkout:
>> </path/to/workdir>".
>
> That actually is how I read his message.

That's what I meant.

> I think "switch_branches()" that updates HEAD to point at a local branch
> is one good place to lock the branch, but I do not know if it is a good
> idea to hook the check into the codepaths for deletion of the branch using
> "branch -[dD]" and check-out of the branch using "checkout $branch". I
> wonder if it makes sense to add the "checking" hook into much lower level
> in the callchain, perhaps delete_ref(), rename_ref() and update_ref() to
> catch attempts to update "your" current branch by other people.

I'd aim at low-level ref manipulation because too me it affects more
than just "git checkout".

> For that
> matter, instead of switch_branches(), would it make more sense to add this
> lock/unlock logic to symbolic_ref() that repoints HEAD to other branch?

Couldn't find symbolic_ref() in current code. If you meant
create_symref(), yes that would make sense.
-- 
Duy