Re: git confused by rename

Junio C Hamano [off-list ref] writes:

"Michael P. Soulier" [off-list ref] writes:

quoted

#       renamed:    templates/scrc/index.html -> templates/scrc/cres_taps.html
#       modified:   templates/scrc/index.html

Looking at the last two lines here, there is obviously an issue.

I am puzzled.

Not anymore.

Looking at wt-status.c "renamed: A -> B" will be shown only when A and B
are similar enough *and* there is no A remaining in the final result, and
in such a case, "modified: A" should not be shown.

Except for one case.

Because git does not
care how you created B (IOW, it does not matter if B was typed from
scratch with copying and pasting, or created by copying and editing), the
"renamed: A -> B" entry itself is not surprising nor look like a bug at
all,...

The above observation of mine is correct, but I forgot that "git status"
(and the comment in the commit template from "git commit") is generated
internally with "diff-index -B -M".  So if

 (0) had A but not B in the HEAD commit;
 (1) you created B that is very similar to the original A; and
 (2) you modified A beyond recognition;

then git will say "A was modified and B was created by renaming A".

... but its presense at the same time as "modified: A" does feel very
fishy.

So this is not fishy anymore.

This however makes me wonder if "diff-index -B -M" should say B is copied
(instead of being renamed) from A and A is modified in such a case.  I do
not think we would want to make such a change without thinking things,
through.