Re: [boost] [git][multi_index] help merging from develop

Subject: Re: [boost] [git][multi_index] help merging from develop
From: Edward Diener (eldiener_at_[hidden])
Date: 2013-12-25 19:42:04

On 12/25/2013 12:38 PM, Bjørn Roald wrote:
> On 12/25/2013 03:34 PM, Edward Diener wrote:
>> On 12/25/2013 7:26 AM, Bjørn Roald wrote:
>
>>> In fact the first merge into master from develop after the SVN to Git
>>> conversion is important to get right. If not things become confusing as
>>> Git has no sensible common ancestor for the two branches, and what merge
>>> does may surprise you.
>>
>> Then this should be very carefully documented somewhere on the Wiki
>> pages where all Boost developers can easily find it.
>
> agreed, I think it is.  See below.
>
>> I find it mysterious that one cannot do for one's own submodule:
>>
>> git checkout master
>> git merge develop
>> git push
>>
>> so evidently there is much more to this as far as Boost and git is
>> concerned.
>
> Not anything other than the fact the master and develop branch as they
> come out of the conversion from SVN are not really set up as normal git
> branches would.  They are just two separate branches running parallel
> from the infancy of the library with no interconnections in the form of
> recorded merges forming some common parent.  Such a common parent is
> normally used by git merge to end the search in history for change sets
> that may apply to the merge.
>
> So Git may need a bit of care and help from you the first time you merge
> after the conversion to find a sensible place to make such a common
> parent.  Then that is done git will likely do as you expect.
>
> Just doing the canonical merge you describe above as the first time
> merge after conversion will likely work if the head of the develop
> branch and the head of the master branches are in sync.  If not I
> recommend to look in the history of develop for a better commit to do
> the first merge from.  See link below.
>
>> Hopefully what needs to be done will be carefully explained
>> somewhere for all of us git non-experts.
>
> There is a section called "First post-svn conversion merge to master" in:
>
> https://svn.boost.org/trac/boost/wiki/StartModMaint#Gettingreadytoworkonalibrary
>
>
> Is that similar to what you have in mind?

That explanation is excellent. Sorry for the noise !