Re: [PATCH] diff: add --ignore-blank-lines option

[Junio C Hamano <gitster@pobox.com>]

Antoine Pelisse <apelisse@gmail.com> writes:

> On Sun, Jun 9, 2013 at 10:07 PM, Junio C Hamano <gitster@pobox.com> wrote:
>> When any ignore blank option is used, there will be lines that
>> actually has changes (hence should be shown with +/-) but we
>> deliberately ignore their changes (hence, if they ever appear in the
>> hunk, they do so as context lines prefixed with SP not +/-).  When
>> we do so, we show the lines from the postimage in the context.
>
> Don't we actually use preimage (see below) ? I think using pre-image
> allows the patch to be applicable to another tree (but ignoring the
> space changes).

But the result of such patch application is not usually what you
want to use.  If we use postimage (which by the way was a deliberate
design decision we made earlier), at least the review of the patch
is easier because you would see the end result more clearly.

> If we actually hide new blank lines that are in the context, it means
> that we won't be able to apply a patch with 2 new blank lines in the 3
> line context.

Yes, but I do not think the point of --ignore-blank-lines is to
produce a patch that can be applied in the first place.  It is to
allow easier eyeballing.

> Anyway, I'm starting to think that "show blank lines changes near
> other changes" makes sense more and more sense.

Probably.