[U-Boot-Users] Revised custodian git writeup

[Jerry Van Baren <gerald.vanbaren@ge.com>]

Jerry Van Baren wrote:
> Wolfgang Denk wrote:
>> Hello,
>>
>> in message <47954A7D.4070507@gmail.com> you wrote:
>>> I've rewritten the "Tips for maintaining custodian trees" section to 
>>> reflect Wolfgang's request that the "master" branch be used for patches 
>>> for him to pull.
>>>
>>> Conceptually, this is very different from my previous recommendation / 
>>> methodology writeup.  In practice, however, it is a trivial change.  The 
>>> fundamental difference is to create a separate branch ("uboot") to track 
>>> the master repo and rebase the "master" branch against that, instead of 
>>> vice versa.
>> Rebasing the master branch, i. e. the one I'll be pullung from?
>>
>> Are you sure that is a good idea? Note that I (and probably others)
>> will be pulling from that branch, and not only once!
>>
>> Quote from the git-rebase man page:
>>
>> ...
>> NOTES
>>        When you rebase a branch, you are changing its history in a
>>        way that will cause problems for anyone who already has a copy
>>                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>        of the branch in their repository and tries to pull updates
>>        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>        from you. You should understand the implications of using git
>>        ^^^^^^^^^
>>        rebase on a repository that you share.
>> ...
>>
>> Best regards,
>> Wolfgang Denk
> 
> Well, that is what I understood you to be asking for, and it worked this 
> past merge window.  That could have been luck, but I suspect not.
> 
> The conflicting requirements are:
> 1) Wolfgang wishes to pull from the subrepo "master" branch
> 2) Subrepository custodians must rebase to pull the latest changes and 
> fix any merge conflicts so that Wolfgang's pulls don't have merge conflicts.
> 
> I don't believe the rebasing will cause problems because the rebasing is 
> pulling from the u-boot.git master repository (or possibly 
> u-boot-testing.git) which is rebuilding the subrepo "uboot" branch to 
> match the u-boot.git master, and then rebasing the subrepo "master" 
> based on the u-boot.git master.  This will make the subrepo "master" 
> *match* the u-boot.git master *plus* append the new patches to be pulled.
> 
> I think the difference with our use vs. the general case that the 
> warning applies to is that the custodians are making their "master" 
> branch conform exactly to the u-boot.git master branch and then adding 
> on the patches to be pulled.

Adding to this thought, rebasing a custodian repo rewrites its history 
*to match the master u-boot.git repo* (and then add to it).  Based on my 
limited knowledge and experience, I think that is a *good* thing.

If we don't "rewrite" our custodian histories to match the master 
u-boot.git repo history, very quickly it will be impossible to compare 
the custodian repo to the master because the patches will be in 
different order.

We are your slaves,
gvb