Re: Reference a submodule branch instead of a commit

> Jeremy Morton <admin@game-point.net> writes:
> 
> > At the moment, supermodules must reference a given commit in each of
> > its submodules.  If one is in control of a submodule and it changes on
> > a regular basis, this can cause a lot of overhead with "submodule
> > updated" commits in the supermodule.  It would be useful of git allows
> > the option of referencing a submodule's branch instead of a given
> > submodule commit.  How about adding this functionality?
> 
> When somebody downstream fetches from your superproject and grabs
> the set of submodules, how would s/he know what _exact_ state you
> meant to record?  When s/he says "I have your superproject commit X,
> which binds submodule's branch Y at path sub/, and it simply does
> not work.  Your project is broken", how do you go about reproducing
> the exact state s/he had trouble with to help her/him?
> 
> The only thing s/he knows is that the commit used from the submodule
> must be one of the commits that was on branch Y at some point in
> time, hopefully close to the timestamp recorded in the commit in the
> superproject.  And your record in the history of the superproject
> does not tell you more than that, so you wouldn't have any idea
> better than what s/he already has to help.
> 
> Hence, such a "functionality" will never happen, at least in the
> exact form you are describing.
> 
> It is conceivable to add some feature that allows you to squelch the
> report that the submodule recorded in your superproject is not up to
> date from "git status" etc. to help those who thinks it is OK to not
> bind the latest submodule commit to the superproject all the time,
> though.