Re: git mergetool broken when rerere active

Martin von Zweigbergk [off-list ref] writes:

When rerere is enabled, git mergetool uses 'git rerere status' to find
out which files to run the merge tool on. This was introduced in
bb0a484 (mergetool: Skip autoresolved paths, 2010-08-17). Before that,
'git ls-files -u' was used, whether or not rerere was active.

This change caused two problems:

 (1) Before this change, it used to be that case that all conflicts
     would be resolved and added to the index after running 'git
     mergetool' without arguments, i.e. on all files. After the
     change, conflicts of type 'deleted by them' or 'deleted by us'
     would be ignored, since they are not listed shown by 'git rerere
     status'.

Good point.  We used to say "everything that had conflict after a mergy
operation", now we say "everything that rerere attempted resolution but
didn't succeed".  Missing are paths that rerere didn't even attempt to
apply previous resolution at all.

Probably we would need a "git rerere remaining" sobcommand that is similar
to status but also includes the "punted" paths.