100% (was: [PATCH] diffcore-rename: favour identical basenames)

Footnote:

*1* Actually, it is not _that_ bad. The score is not a value between 0 and 
    100, IOW it is _not_ what you see in the output of "diff -M". It is an 
    unsigned short between 0 and MAX_SCORE, which is defined in 
    diffcore.h as 60000.0.

    The Levenshtein distance between two filenames cannot be larger than 
    the sum of their lengths, so it should be relatively safe. That is, if 
    you don't have such insanely long paths as e.g. egit. But even there, 
    the paths share most of their directories, and therefore the distances 
    should be much, much smaller in real life.

As a note aside: would it be possible to always round downwards when
computing similarities or converting between them?

I very much would like to see the 100% figure reserved for identity.
This is particularly relevant when interpreting the output of git-diff
--name-status with regard to R100, C100 and similar flags.

-- 
David Kastrup