Re: [RFH] hackday and GSoC topic suggestions

[Jeff King <peff@peff.net>]

On Tue, Feb 11, 2014 at 11:38:09AM -0800, Junio C Hamano wrote:

> Junio C Hamano <gitster@pobox.com> writes:
> 
> > Jeff King <peff@peff.net> writes:
> >
> >>  - Branch rename breaks local downstream branches
> >>    http://article.gmane.org/gmane.comp.version-control.git/241228
> >
> > If you have a branch B that builds on A, if you are renaming A to C,
> > you may want B to automatically set to build on C in some cases, and
> > in other cases your renaming A is done explicitly in order to severe
> > the tie between A and B and setting the latter to build on C can be
> > a bad thing---after all, the user's intention may be to create a
> > branch A starting at some commit immediately after this rename so
> > that B will keep building on that updated A.
> >
> > So I am not sure if this is a bug.
> 
> Having said that, the current behaviour of leaving B half-configured
> to build on a missing branch is undesirable. If we were to change
> this so that any branch B that used to build on branch A being
> renamed to build on the branch under the new name C, the user may
> have to do an extra "--set-upstream-to A" on B after recreating A if
> this was done to save away the current state of A to C and then keep
> building B on an updated A, so we may have to give _some_ clue what
> we are doing behind their back when we rename, e.g.
> 
> 	$ git branch -m A C
>         warning: branch B is set to build on C now.
> 
> or something.

Yeah, I agree. I think most of the time people would want the dependency
to move with the branch, and the key is being clear about it so the user
can override. I don't think there is a problem with overriding with
`--set-upstream-to` after the fact, rather than giving a special option
to the move operation.

There was a team working on this at the hackday, and they seemed to make
reasonable progress, but I haven't seen the final output yet. Most teams
did not finish their projects, or if they did, I didn't get a chance to
coach them through the patch submission process. I'll hopefully be
revisiting those in the next week or two as they finish them up offline.

My goal is to get them all posting to the list themselves, but I fear I
may have to pick up the pieces in some cases.

-Peff