Re: What's cooking in git.git (Aug 2015, #05; Fri, 28)

Christian Couder [off-list ref] writes:

quoted

* dt/refs-bisection (2015-08-28) 5 commits
 - bisect: make bisection refs per-worktree
 - refs: make refs/worktree/* per-worktree
 - SQUASH???
 - path: optimize common dir checking
 - refs: clean up common_list

 Move the refs used during a "git bisect" session to per-worktree
 hierarchy refs/worktree/* so that independent bisect sessions can
 be done in different worktrees.

 Will merge to 'next' after squashing the update in.

Sorry if I am missing something or repeating what myself or someone
else like Michael already said, but in the current doc there is:

       Eventually there will be no more revisions left to bisect, and
you will have been left with the first bad kernel revision in
       "refs/bisect/bad".

If we now just use "refs/worktree/bisect/bad" instead of
"refs/bisect/bad", it might break scripts that rely using
"refs/bisect/bad".

Christian, thanks for raising this one.

I do recall the thread and I might be the somebody like Michael you
remember, e.g. $gmane/275105---which did mention that "git bisect"
would not need changing if we kept refs/bisect/.

What was the reason why we chose to move to refs/worktree/ again?  I
do not think there was an issue that we cannot keep refs/* in
general shared while having one (or more) subhierarchy of it per
worktree (otherwise we would not be using refs/worktree/*, but using
something outside refs/, like $GIT_DIR/worktree-refs/).  Was there an
objection to refs/bisect being private from aesthetics point of view
(i.e. forcing everything per-worktree in refs/worktree/ would prevent
proliferation of refs/this and refs/that that need to be private
case by case), ignoring the practical issue of compatibility issues
around existing tools?

I think one example of script, "gitk --bisect", does want to show
the DAG limited by bisect refs, but it does so using plumbing
without having to say refs/bisect/bad itself.  Perhaps the thinking
(or lack of enough of it) went that no other uses by scripts need to
peek directly into refs/bisect/ hierarchy?