Sparse checkout in worktree

Sparse checkout in worktree

[Michael J Gruber]

Hi there,

I'm wondering how much it would take to enable worktree specific sparse
checkouts. From a superfluous look:

- $GIT_DIR/info/sparse_checkout needs to be worktree specific
- We don't have much tooling around sparse to speak of at all.

The endgoal would be to have something like

git checkout [--sparse <pattern>]...

which sets up the sparse_checkout file and "git worktree" to pass any
--sparse option on to "git checkout".

While in an ideal world we all have micro repos, in the real world we
often have larger repos with mostly independent subdirs. For a quick fix
on a side branch in a subdir, a new sparse worktree would be an ideal
lean solution.

As it is, "git stash save && git checkout" is leaner but interrupts the
workflow more, and a local "git clone" with links and alternates is
leaner, too, but conceptually overkill if you want to work quickly on an
existing side branch.

Cheers,
Michael

Re: Sparse checkout in worktree

[Duy Nguyen]

On Wed, Nov 25, 2015 at 1:40 PM, Michael J Gruber
<git@drmicha.warpmail.net> wrote:
> Hi there,
>
> I'm wondering how much it would take to enable worktree specific sparse
> checkouts. From a superfluous look:
>
> - $GIT_DIR/info/sparse_checkout needs to be worktree specific

It already is.

> - We don't have much tooling around sparse to speak of at all.
>
> The endgoal would be to have something like
>
> git checkout [--sparse <pattern>]...
>
> which sets up the sparse_checkout file and "git worktree" to pass any
> --sparse option on to "git checkout"

Or.. convert pathspec specified at 'git-checkout' (or git-worktree)
into sparse patterns. For example,

git worktree add --sparse some-path branch --  foo/

will automatically create sparse-checkout file that limits to 'foo'.
Not easy (and in some cases probably impossible), but it's more
intuitive.
.
> While in an ideal world we all have micro repos, in the real world we
> often have larger repos with mostly independent subdirs. For a quick fix
> on a side branch in a subdir, a new sparse worktree would be an ideal
> lean solution.

Sparse checkout should eventually be replaced with something better
that does not keep full tree in index, but I don't think anybody is
working on that..

> As it is, "git stash save && git checkout" is leaner but interrupts the
> workflow more, and a local "git clone" with links and alternates is
> leaner, too, but conceptually overkill if you want to work quickly on an
> existing side branch.
--
Duy

Re: Sparse checkout in worktree

[Michael J Gruber]

Duy Nguyen venit, vidit, dixit 25.11.2015 20:38:
> On Wed, Nov 25, 2015 at 1:40 PM, Michael J Gruber
> <git@drmicha.warpmail.net> wrote:
>> Hi there,
>>
>> I'm wondering how much it would take to enable worktree specific sparse
>> checkouts. From a superfluous look:
>>
>> - $GIT_DIR/info/sparse_checkout needs to be worktree specific
> 
> It already is.

But where should I put the worktree specific sparse_checkout file? Is
Documentation/technical really the only place to find information about
this? And to make the existing tree sparse, do I need to rm -r and
checkout sparsely?

Michael

Re: Sparse checkout in worktree

[Duy Nguyen]

On Wed, Nov 25, 2015 at 8:44 PM, Michael J Gruber
<git@drmicha.warpmail.net> wrote:
> Duy Nguyen venit, vidit, dixit 25.11.2015 20:38:
>> On Wed, Nov 25, 2015 at 1:40 PM, Michael J Gruber
>> <git@drmicha.warpmail.net> wrote:
>>> Hi there,
>>>
>>> I'm wondering how much it would take to enable worktree specific sparse
>>> checkouts. From a superfluous look:
>>>
>>> - $GIT_DIR/info/sparse_checkout needs to be worktree specific
>>
>> It already is.
>
> But where should I put the worktree specific sparse_checkout file? Is
> Documentation/technical really the only place to find information about
> this? And to make the existing tree sparse, do I need to rm -r and
> checkout sparsely?

Ahh.. worktree-specific files of the checkout "foo" stay in
$GIT_DIR/repos/foo. So sparse-checkout path should be
$GIT_DIR/repos/foo/info/sparse-checkout. This is another good reason
to add 'git checkout --edit-sparse' that opens the sparse-checkout
file for you to update. Or you could use 'git rev-parse --git-path
info/sparse-checkout" to get full path.
-- 
Duy

Re: Sparse checkout in worktree

[Michael J Gruber]

Duy Nguyen venit, vidit, dixit 25.11.2015 21:17:
> On Wed, Nov 25, 2015 at 8:44 PM, Michael J Gruber
> <git@drmicha.warpmail.net> wrote:
>> Duy Nguyen venit, vidit, dixit 25.11.2015 20:38:
>>> On Wed, Nov 25, 2015 at 1:40 PM, Michael J Gruber
>>> <git@drmicha.warpmail.net> wrote:
>>>> Hi there,
>>>>
>>>> I'm wondering how much it would take to enable worktree specific sparse
>>>> checkouts. From a superfluous look:
>>>>
>>>> - $GIT_DIR/info/sparse_checkout needs to be worktree specific
>>>
>>> It already is.
>>
>> But where should I put the worktree specific sparse_checkout file? Is
>> Documentation/technical really the only place to find information about
>> this? And to make the existing tree sparse, do I need to rm -r and
>> checkout sparsely?
> 
> Ahh.. worktree-specific files of the checkout "foo" stay in
> $GIT_DIR/repos/foo. So sparse-checkout path should be
> $GIT_DIR/repos/foo/info/sparse-checkout. This is another good reason
> to add 'git checkout --edit-sparse' that opens the sparse-checkout
> file for you to update. Or you could use 'git rev-parse --git-path
> info/sparse-checkout" to get full path.
> 

[ "worktrees", not "repos" ]

Maybe creating an empty info dir by default would help already - I had
looked in there but didn't find anything.

OTOH, config is common: core.sparseCheckout
So, the per worktree "switch" is the presence of the sparse-checkout file.

Michael

Re: Sparse checkout in worktree

[Duy Nguyen]

On Wed, Nov 25, 2015 at 9:44 PM, Michael J Gruber
<git@drmicha.warpmail.net> wrote:
> OTOH, config is common: core.sparseCheckout
> So, the per worktree "switch" is the presence of the sparse-checkout file.

Oh.. but yeah, splitting config file per worktree is on my todo list.
Or you can help finish it [1] if you want to make it happen faster

[1] http://article.gmane.org/gmane.comp.version-control.git/266520
-- 
Duy