Re: A rebase regression in Git 2.18.0

[Junio C Hamano <gitster@pobox.com>]

Elijah Newren <newren@gmail.com> writes:

>   - Add a flag to turn off directory rename detection, and set the
> flag for every call from am.c in order to avoid problems like this.

I'd say this is the only practical solution, before you deprecate
the "pipe format-patch output to am -3" style of "git rebase" (and
optionally replace with something else).

The whole point of "am -3" is to do _better_ than just "patch" with
minimum amount of information available on the pre- and post- image
blobs, without knowing the remainder of the tree that the patch did
not touch.  It is not surprising that the heuristics that look at
the unchanging part of the tree to infer renames that may or may not
exist guesses incorrectly, either with false positive or negative.
In the context of "rebase", we always have all the trees that are
involved.  We should be able to do better than "am -3".