Re: [boost] Git Modularization Review no vote heads-up

Subject: Re: [boost] Git Modularization Review no vote heads-up
From: Jürgen Hunold (jhunold_at_[hidden])
Date: 2013-05-30 12:46:48

Hi Volodya

On Thursday, 30. May 2013 09:44:00 Vladimir Prus wrote:
> On 26.05.2013 17:15, Jürgen Hunold wrote:
> > I even fear that building historic boost is from git is not even possible.
> > The source tree rewriting needed for the modularisation itself is quite
> > heavy. This is the main reason why Dave proposed dropping the history
> > altogether at the first conversion attempt I think. The only "real"
> > reason (at least for me) for keeping history is the ability to use "git
> > diff" and "git blame" and follow edits and reading commit messages.
> > 
> > Those are my personal opinions, but I guees Rene and Volodya are on the
> > same track here.
> 
> Yep. I primarily care that in the new git repository, I can go "git blame"
> and "git log" and "git show" without hassle.

I am glad to hear that I am not too far off track here ;-)

> I *suspect* that "git mv" after conversion won't be quite as smooth, e.g. if
> I print a previous commit it will have "v2/" prefix in all paths, which
> will slightly complicate things. 

Yes, it will.

> And practically speaking, the history is
> only important from the point where jam moved into build/v2/engine.

Good to hear.

> Top-level scripts should not be a problem; we can code them to detect which
> layout is used (well, I can do that), and I don't think that building
> previous Boost releases from git repository is a use case were need to
> support -- even the structure of the checkout will be different, so
> checking out from git, rearranging, and then building is not 100%
> reproduction of past builds anyway. I.e. we probably need not bother with
> rewriting history of top-level scripts.

That what I meant by saying "...building historic boost is from git is not 
even possible."

> So where are we now? Daniel previously said:
> 
> 	- Send tools/build/v2/* to the top level of the build repository.
> 	- Send the rest of tools/build to historic/build in the build repo.
> 	- Send tools/jam to historic/jam in the build repo.
> 
> and it looks like it was actually done? 

Yes, there were at least two conversions with path rewriting.

> I don't know whether 'historic' is a
> branch or directory name, but it does not matter much. However, it looks
> like further tweak was made to disable this?

Yes, it looks like running the regular expression sed over each commit blew up 
conversion time to 4 hours. That seems to be the current bottleneck. 

But I still cannot get my adapded patch from Steven for symlinking to work 
with the regression tests and at least 5 submodules are still missing.

My 2 cents:

Finalise the conversion  and get the libraries etc. up and running.
Then enable the v2/ removal again and test if everything is still working. 
Done.

Yours,

Jürgen
-- 
* Dipl.-Math. Jürgen Hunold  ! 
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