Re: Annoyance wrt ref@{1} and reflog expiry

> Sergey Organov <sorganov@gmail.com> writes:
> 
> >> But then if you do
> >>
> >>     $ git reflog expire --expire=now refs/heads/newbranch
> >>     $ git commit --allow=empty -m two
> >>     $ git show -s newbranch@{1}
> >> ...
> >> And it is unintuitive.  It is understandable to the users that all
> >> the ref history before "reflog expire" is lost---it was what the end
> >> user asked Git to do.  But after creating one commit on the state
> >> (or do anything else that moves the ref) and finding it regrettable,
> >> "git reset --hard @{1}" should be a viable way to recover from the
> >> mistake made _after_ the reflog entries were expired.
> 
> And the expiration does not have to be --expire=now; what happens
> more often is when I expire entries older than (say) a week, the
> reflog for a topic branch that hasn't seen any activity may become
> empty.  Then I "git am" the new round on the same base, compare and
> then update, perhaps like so:
> 
>     ... git reflog expire has emptied the log for so/topic ...
>     $ git checkout so/topic
>     $ git log master.. ;# remind myself what the previous round had
>     $ git checkout master... ;# detach HEAD at the previous base
>     $ git am -s ./+so-v2-topic ;# apply
>     $ git range-diff @{-1}... ;# compare
>     $ git checkout -B so/topic
> 
> Now, I'm used to see this work after the above:
> 
>     $ git range-diff @{1}... ;# compare again just to be sure
> 
> but because there is only one entry in the reflog, which was created
> when the last "checkout -B" updated the so/topic branch, "there is
> only one entry" error kicks in.
> 
> > Makes sense. The first solution that comes to mind is immediately record
> > current state after "reflog expire", so that there will be 2 entries for
> > the case in question.
> 
> Perhaps.  
> 
> Or we could change the lookup side to use the value of the ref
> itself when asked for @{0}, and use the "old" side of the only entry
> when asked for @{1}.  That way, we do not need to play games with an
> artificial entry at all, which may be a better solution.