Re: [PATCH] array index mixup

Matthias Lederhofer [off-list ref] writes:

I dunno if this is really an index mixup or was intended.  If this is
intended please add a comment what it's for.  (Without this you get
rename information, perhaps this is the reason.)

That is exactly the reason -- it was a temporary workaround
which nobody noticed so far.

The right fix would involve updating diff_resolve_rename_copy so
that it does not rely on the comparison of path names (that
means DIFF_PAIR_RENAME() macro needs to change), and instead
mark the pairs synthesized in diffcore-rename as such, and use
that to tell if a pair is a result of rename/copy [*1*].

Your other patch (not the one to change the index of the array
used for labels, but the one that extracts the pathname out of
the syntax to name a blob by path in an arbitrary tree object)
could be safely applied when that happens.


[Footnote]

*1* If somebody wants to do this, one thing to watch out for is
matching up of broken pairs.  If a pair originally broken by
diffcore-break (because they were dissimilar enough according to
the option given to -B flag) are merged into one by
diffcore-rename (because they were similar enough according to
the option given to -M flag), we should _not_ say the resulting
pair is renamed.  In general, the threashold for breaking should
be lower than diffcore-rename to merge them for a sane use, so
this might be a non-issue in practice, though.