Merging (only) subdirectories

Merging (only) subdirectories

[Howard Miller]

This might take a bit of explaining... and for those familiar with it
I'm talking about Moodle themes which will help one or two of you.

We develop themes for Moodle. All themes live in their own
self-contained directory. So, when creating a new theme we create a
new branch (from some version of Moodle - more in a moment) then a new
theme folder, do the dev, and commit/push the results.

We have lots of clients and for one reason or another we have lots of
different versions of Moodle and/or different customisations. So each
client ends up with their own branch.

The problem comes when Client A wants to purchase Theme B. We can't
just merge the theme branch because all the rest of the project
contains (potentially) a different version of Moodle. So we have to do
lots of messing around to get the theme branch in and/or loose the
theme commit history in the process.

What I would like to do is to be able to merge branch B into branch A
but ONLY stuff that concerns the theme directory. I don't think this
is possible. I'm reluctant to keep themes in a completely separate
repo as that just makes testing them more problematic.

Does anybody have any thoughts or advice (assuming this all makes
sense)?  Cheers!

Re: Merging (only) subdirectories

["Martin Krüger"]

> 
> The problem comes when Client A wants to purchase Theme B. We can't
> just merge the theme branch because all the rest of the project
> contains (potentially) a different version of Moodle. So we have to do
> lots of messing around to get the theme branch in and/or loose the
> theme commit history in the process.
> 
I would say you are not working best practice with git. The idea of commit is a atomic  change of the whole project.  It seems like you mixed completely unrelated changes in a commit.

You can try as a resolution:
git rebase master  (on a temporary-branch)
git format-patch master

Strip the patches with filterdiff

Apply the stripped patches to another temporary-brach.
Merge to the target-Branch.

Best regards
     martin

Re: Merging (only) subdirectories

[Howard Miller]

2010/12/1 "Martin Krüger" <martin.krueger@gmx.com>:

>>
> I would say you are not working best practice with git. The idea of commit is a atomic  change of the whole project.  It seems like you mixed completely unrelated changes in a commit.
>
> You can try as a resolution:
> git rebase master  (on a temporary-branch)
> git format-patch master
>
> Strip the patches with filterdiff
>
> Apply the stripped patches to another temporary-brach.
> Merge to the target-Branch.
>
> Best regards
>     martin

thanks Martin,

There's a whole bunch of stuff there that I am not familiar with so I
need to do some reading!  When you say we are not using best practices
can you elaborate? I am very open to improving the way we do things.

Howard

Re: Merging (only) subdirectories

[Howard Miller]

2010/12/1 "Martin Krüger" <martin.krueger@gmx.com>:
>

>>
> I would say you are not working best practice with git. The idea of commit is a atomic  change of the whole project.  It seems like you mixed completely unrelated changes in a commit.
>

> Best regards
>     martin
>

Actually... thinking some more... that was actually my question (sorry
if I wasn't clear). We know that we are probably not doing this the
best way but we can't work out the right/better way. I'm looking for
help to organise our workflow with git better,

Thanks :)

Re: Merging (only) subdirectories

[Nguyen Thai Ngoc Duy]

On Wed, Dec 1, 2010 at 6:18 PM, Howard Miller
<howard@e-learndesign.co.uk> wrote:
> What I would like to do is to be able to merge branch B into branch A
> but ONLY stuff that concerns the theme directory. I don't think this
> is possible. I'm reluctant to keep themes in a completely separate
> repo as that just makes testing them more problematic.

I don't know. Maybe you can use topic branch. The idea is that you and
other theme designers branch out from a known point, then make changes
in the theme directory only. You guys can merge from each other's tree
because nobody would change anything outside theme directory.
Occasionally you can merge back upstream for testing with new code,
but don't push that merge until your theme is ready. Once your theme
rolls out, you can either keep working on your topic branch, or throw
it away and branch out again.

Also, please consider submodules if theme dir is totally independent.
I don't see how it makes it problematic for testing. git-subtree [1]
might be of your interest too.

[1] https://github.com/apenwarr/git-subtree
-- 
Duy

Re: Merging (only) subdirectories

[Howard Miller]

On 1 December 2010 12:36, Nguyen Thai Ngoc Duy <pclouds@gmail.com> wrote:
> On Wed, Dec 1, 2010 at 6:18 PM, Howard Miller
> <howard@e-learndesign.co.uk> wrote:
>> What I would like to do is to be able to merge branch B into branch A
>> but ONLY stuff that concerns the theme directory. I don't think this
>> is possible. I'm reluctant to keep themes in a completely separate
>> repo as that just makes testing them more problematic.
>
> I don't know. Maybe you can use topic branch. The idea is that you and
> other theme designers branch out from a known point, then make changes
> in the theme directory only. You guys can merge from each other's tree
> because nobody would change anything outside theme directory.
> Occasionally you can merge back upstream for testing with new code,
> but don't push that merge until your theme is ready. Once your theme
> rolls out, you can either keep working on your topic branch, or throw
> it away and branch out again.
>
> Also, please consider submodules if theme dir is totally independent.
> I don't see how it makes it problematic for testing. git-subtree [1]
> might be of your interest too.
>
> [1] https://github.com/apenwarr/git-subtree
> --
> Duy
>

Thanks! Again, I need to go and do some reading to see if those things
fit my needs.

Re: Merging (only) subdirectories

[Enrico Weigelt]

* Nguyen Thai Ngoc Duy <pclouds@gmail.com> wrote:

> Also, please consider submodules if theme dir is totally independent.
> I don't see how it makes it problematic for testing. git-subtree [1]
> might be of your interest too.
> 
> [1] https://github.com/apenwarr/git-subtree

Another option could be completely splitting off the themes to
their own branches (eg. using git-filter-branch), check them
out in an separate workdir and use unionfs to get a combined/merged
view of the working trees.

So, you'd actually have to fully separate branches, checked out
in their own worktrees/repos:

a) mainapp (the main application)
b) theme (the current theme you're working on)

For testing/runtime, the webserver gets a union'ed tree,
which just merges both namespaces (from host filesystems's, not
git's view) together. Your actual development happens in the theme
repo only.


On actual deployment (if you're using git here, too), you can simply
merge both branches together (will be just an passive - aka: 
merge-down-only - branch).


cu
-- 
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 Enrico Weigelt, metux IT service -- http://www.metux.de/

 phone:  +49 36207 519931  email: weigelt@metux.de
 mobile: +49 151 27565287  icq:   210169427         skype: nekrad666
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 Embedded-Linux / Portierung / Opensource-QM / Verteilte Systeme
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Re: Merging (only) subdirectories

[Howard Miller]

> Another option could be completely splitting off the themes to
> their own branches (eg. using git-filter-branch), check them
> out in an separate workdir and use unionfs to get a combined/merged
> view of the working trees.
>
> So, you'd actually have to fully separate branches, checked out
> in their own worktrees/repos:
>
> a) mainapp (the main application)
> b) theme (the current theme you're working on)
>
> For testing/runtime, the webserver gets a union'ed tree,
> which just merges both namespaces (from host filesystems's, not
> git's view) together. Your actual development happens in the theme
> repo only.
>
>
> On actual deployment (if you're using git here, too), you can simply
> merge both branches together (will be just an passive - aka:
> merge-down-only - branch).

Ok... thanks for that. I'll have a look at that as well.

This type of thing was actually the one thing I can think of that
cvs/svn made easy as they keep the repo info in each directory :)  (Do
I get thrown out for saying that?)

Re: Merging (only) subdirectories

[Enrico Weigelt]

* Howard Miller <howard@e-learndesign.co.uk> wrote:

> This type of thing was actually the one thing I can think of that
> cvs/svn made easy as they keep the repo info in each directory :)  

Besides the fact that their underlying data model makes things
like merging particularily hard (svn initially had no branch
concept at all ;-o).

BTW: M$-TFS combines the worst of all ...


cu
-- 
----------------------------------------------------------------------
 Enrico Weigelt, metux IT service -- http://www.metux.de/

 phone:  +49 36207 519931  email: weigelt@metux.de
 mobile: +49 151 27565287  icq:   210169427         skype: nekrad666
----------------------------------------------------------------------
 Embedded-Linux / Portierung / Opensource-QM / Verteilte Systeme
----------------------------------------------------------------------