Re: Using --word-diff breaks --color-moved

[james harvey <jamespharvey20@gmail.com>]

On Wed, Oct 31, 2018 at 1:42 PM Stefan Beller <sbeller@google.com> wrote:
>
> On Tue, Oct 30, 2018 at 7:06 PM james harvey <jamespharvey20@gmail.com> wrote:
> > I think "--color-moved" should have precedence over "--word-diff".
>
> I agree for precedence as in "work well together". Now we'd need
> to figure out what that means. In its current form, the move
> detection can detect moved lines across diff hunks or file
> boundaries.
>
> Should that also be the case for word diffing?
> I think word diffing is mostly used for free text, which has different
> properties compared to code, that the color-moved was originally
> intended for.

That's how I think of it too.  I think I'd be fine if word diffing
stayed not being able to be detected with moved lines across diff
hunks or file boundaries.

> >   I
> > cannot think of a scenario where a user would supply both options, and
> > actually want "--word-diff" to take precedence.  If I'm not thinking
> > of a scenario where this wouldn't be desired, perhaps whichever is
> > first as an argument could take precedence.
>
> word diffing and move detection are completely orthogonal at the moment.
> Instead of option order, I'd rather introduce a new option that tells us
> how to resolve some corner case. Or in the short term we might just
> want to raise an error?

I'm fine with option order not mattering, as it does now.  Was
assuming it didn't matter now, but mentioned trying it in case it
worked that way.  And, mentioned it as an alternative in case it
turned out the two could conflict in some corner case.  I think
defaulting to resolving one way or the other with an optional option
to go the other way makes sense.

> > (The same behavior happens if 4+ lines are moved and
> > "--color-moved{default=zebra}" is used, but below
> > "--color-moved=plain" is used to be a smaller testcase.)
> >
> > [...]
>
> This sounds like you are asking for two things:
> (1) make color-moved work with words (somehow)
> (2) allow the user to fine tune the heuristics for a block,
>     such that default=zebra would still work.

I was asking for #1.  #2 might be a good idea, but I just tried using
"--color-moved" for the first time the other day, so haven't used it
enough to get that far.  If they worked together, I'm not sure yet if
I'd be using plain or zebra.  I mentioned "4+ lines" because I can
remember something said zebra only worked with more than 3 lines.  Not
sure where that was.  I thought it was the manpage, but I'm not seeing
that in there now.