Re: subtree split includes unrelated commits

I hope I got this reply sent to the right thread.

I found the issue to be related with the following change in git-subtree.sh:

quoted

Revision: 933cfeb90b5d03b4096db6d60494a6eedea25d03
Author: Dave Ware [off-list ref]
Date: 15.01.2016 01:41:43
Message:
contrib/subtree: fix "subtree split" skipped-merge bug

quoted

'git subtree split' can incorrectly skip a merge even when both parents
act on the subtree, provided the merge results in a tree identical to
one of the parents. Fix by copying the merge if at least one parent is
non-identical, and the non-identical parent is not an ancestor of the
identical parent.

Hmm... I'm not expert on the implementation details of subtree split.
But I wonder if this should have said "if at least one parent is
non-subtree-identical"?  Maybe that's what was meant. I just went
through writing a similar "degenerate  merge" (to adopt the
filter-repo terminology for it) detection for git-alltrees, although
I'm not sure alltrees would handle this particular case to your liking
either.  I think I discard merges if either parent is
subtree-identical to the merge commit, probably keeping only the
matching branch, but I'm not sure that's always true, and that's
there, not here.

Cheers,
Doug

I hope I got this reply sent to the right thread.

Oops, probably forgetting the Re broke that.