Re: [PATCH v3 1/2] merge-file: let conflict markers match end-of-line style of the context

[Johannes Schindelin <Johannes.Schindelin@gmx.de>]

Hi Junio,

On Mon, 25 Jan 2016, Junio C Hamano wrote:

> Johannes Schindelin <johannes.schindelin@gmx.de> writes:
> 
> > We actually do not have to look at the *entire* context at all: if the
> > files are all LF-only, or if they all have CR/LF line endings, it is
> > sufficient to look at just a *single* line to match that style. And if
> > the line endings are mixed anyway, it is *still* okay to imitate just a
> > single line's eol: we will just add to the pile of mixed line endings,
> > and there is nothing we can do about that.
> 
> Isn't there one thing we can do still?  If we use CRLF for the
> marker lines when the content is already mixed, I'd think it would
> help Notepad (not necessary for Notepad2 or Wordpad IIUC) by making
> sure that they can see where the marker lines end correctly.

Not sure. You might end up with a very long line (containing plenty of LF
"characters") and the conflict marker *at the end* of said line, with a
CR/LF after it. I would not call that particularly helpful.

Seeing as we really cannot do anything in this case, I thought it would be
a good idea to avoid trying (and failing) to be smart here.

> > Note that while it is true that there have to be at least two lines we
> > can look at (otherwise there would be no conflict), the same is not true
> > for line *endings*: the three files in question could all consist of a
> > single line without any line ending, each. In this case we fall back to
> > using LF-only.
> 
> Yeah, this is tricky, and from the same "helping Notepad that
> concatenates lines with LF-only" perspective I should perhaps be
> suggesting to use CRLF in such a case, too, but I would say we
> should not do so.  Three variants of a LF-only file may have
> conflict at the incomplete last line, and if we only look at their
> "no EOL"-ness and decide to add CRLF to the result, that would be
> irritatingly wrong.

Oh, but there is the fall-back to the first line. So if we have three
variants of an LF-only file, the logic will figure out that LF-only
end-of-lines are to be used.

So the *only* case where we really have to pick and choose is when all
three files contain only one (or no) line that is not terminated by a line
feed.

I briefly considered to choose EOL_NATIVE in that case, but I really do
not like that unnecessary deviation from Linux Git.

Ciao,
Dscho