2009/4/9 Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>: > Hello, > > On Thu, Apr 09, 2009 at 08:01:04PM +0200, Bert Wesarg wrote: >> 2009/4/9 Ira Weiny <weiny2@xxxxxxxx>: >> > On Thu, 9 Apr 2009 14:43:37 +0200 >> > Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx> wrote: >> >> You might want to check >> >> >> >> http:// thread.gmane.org/gmane.comp.version-control.git/114581 >> > >> > Ah this brings up more issues I had not thought about... :-( But perhaps >> > Bert's work could be used to help implement "rm". Thoughts? >> No, it wont help. Because the base and tip of the topic should not >> changed in respect to the old state (expect for .topdeps of course). >> >> If you really want to remove a dependency, you need to revert a merge >> of this dep from the topic base. which is not possible today, or maybe >> I have just an idea for this: >> >> 'topic': the topic >> 'base': the base of the topic, i.e. a merge from all dependent >> topics dep0, ..., depN >> >> say you want to remove dep0 >> >> 1) merge all deps dep1, ..,depN into 'new-base' >> >> 2) merge 'new-base' into base with the merge driver 'theirs', that >> would overwrite all changes from dep0 in the 'base' >> >> 3) update 'topic' to the updated 'base' >> >> Any thoughts from someone who knows more than me? > Some time ago I thought about a similar issue: > > I based a branch on top of the Linux tree of the ARM maintainer (in the > following called "rmk") and decided later to base it on top of Linus' > tree. So I did ~: > > git checkout refs/top-bases/$branch > git merge -s theirs linus/master > git checkout $branch > sed -i s,rmk,linus, .topdeps > git add -f .topdeps > git commit -m $commitmsg > tg update > > When I thought about it with pencil and paper back then, I saw a problem > with that approach. Now I invested some time now to verify it really > exists: In fact I reverted the changes in the rmk/master branch. > Consider Linus pulls from rmk and I update my topgit branch. Guess what > happens? Linus' pull + my revert yield Linus' tree without rmk's > changes. > > Here is my recipe: > > # prepare linus/master > git init > echo 'VERSION=2.6.28' > Makefile > git add Makefile; git commit -m 'v2.6.28' > git branch -m master linus/master > > # prepare rmk/master > git checkout -b rmk/master > echo 'support for some machine' > arm.c > git add arm.c; git commit -m 'support for some machine' > > # new topgit branch > tg create t/test > echo change > lib.c > git add lib.c; git commit -m 'tralala' > > # Linus goes on ... > git checkout linus/master > echo 'VERSION=2.6.29-rc1' > Makefile > git add Makefile; git commit -m 'v2.6.29-rc1' > > # "rebase" test branch on linus/master > git checkout refs/top-bases/t/test > git symbolic-ref HEAD refs/top-bases/t/test > git merge --no-commit linus/master > git read-tree linus/master > git commit > rm arm.c > git checkout t/test > sed -i s/rmk/linus/ .topdeps > git add .topdeps; git commit -m 'change dep: rmk/master -> linus/master' > tg update > > # Linus pulls from rmk > git checkout linus/master > git merge rmk/master > > # update test to linus+rmk > git checkout t/test > tg update > > # inspect: > git diff linus/master refs/top-bases/t/test > > The last command shows that refs/top-bases/t/test doesn't have arm.c > :-/ > > I'm sure the dependency deletion has exactly the same problem. You're probably right. I just found the old discussion about dependencies removal [1]: On zo, 2008-09-21 at 16:24 +0200, Petr Baudis wrote: > The problem is that you can undo the merge content, but not the history > information. So this revert can e.g. propagate even into branches which > still *should* depend on the other branch, you get into trouble when you > want to make your branch depend on the other one anyway, etc. On di, 2008-09-23 at 15:27 +0200, Petr Baudis wrote: > what we can't make to work is just the > most generic case, but e.g. if master is a *leaf* branch nothing else > depends on and it can't get the branch through multiple paths, you can > do the dependency removal rather easily (if it can get through multiple > paths, you can still do it but you might have to deal with big > conflicts). Maybe the leaf solution could be done. Only directly depending branches from the transitive reduction should be removable. This would help for the 'tip'/'current' branch usecase, for collecting topics. Bert [1] http://thread.gmane.org/gmane.comp.version-control.git/95458/focus=96093 > > Best regards > Uwe -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html