Re: diff-mode misinterprets empty lines.

[David Kastrup <dak@gnu.org>]

Jim Meyering <jim@meyering.net> writes:

> Since I was thinking of using that new option always, I considered
> changing the source to make the default in my private binary be to
> enable the new option.  Since I'd rather not have to make private
> changes, what do you think about having a compile-time option to
> change the default?  Not even a configure-time flag.
>
> Since Emacs may eventually change to accept the new format, it may
> make sense to change the default and to provide a
> --no-suppress-blank-empty option.

No, it does not make sense to change the default.  Emacs is just one of
many tools processing diff output.  I remember gratuitous breakage of
git, too.  There are far too many tools relying on the _documented_ diff
output formats (please read
(info "(diff) Context")
for a detailed explanation of the diff formats) that it makes sense
breaking things all around for no tangible benefit.

I don't understand why this change was made in the first place, and I
don't understand why people would want to gratuitously make the format
less reliable to parse by tools, when the main usage _is_ the
application by independent tools.

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum