D3212: patch: implement a new worddiff algorithm

[spectral (Kyle Lippincott)]

spectral added inline comments.

INLINE COMMENTS

> color.py:94
> +    'diff.deleted.changed': 'red',
> +    'diff.deleted.unchanged': 'red dim',
>      'diff.diffline': 'bold',

These are the first uses of 'dim' in the default set of things, and I don't think we can rely on it; for color.mode=auto, we really mean "ansi" (aka ecma48) (unless on windows), and don't do any detection of capabilities, so we just output \e[2m and some terminals just ignore that (like mine, rxvt-unicode v9.22).  If using color.mode=terminfo, we at least get error messages (I did --config color.log.user='dim green'):

ignoring unknown color/effect 'dim' (configured in color.log.user)

Apparently cygwin doesn't advertise 'dim', and while the linux virtual console advertises it and supports it, it doesn't actually support a dim color (at least on my machine), it just always puts it in a weird blue :)

I think I'd prefer that `changed` be bold and `unchanged` be non-bold.  For most terminals, that'll lead to a visible difference in intensity (bold being brighter unless using a weird palette), and for those that aren't configured for that, it'll at least be a heavier weight.  It's better than having literally zero difference between them without any explanation why.  I think it'll also be more obvious which lines have it; in your screenshot the difference between dim and regular is pretty subtle.

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D3212

To: quark, #hg-reviewers, durin42
Cc: spectral, mercurial-devel