Re: [bug-diffutils] New diff options/features

[Duncan Moore]

On 26/09/2010 21:07, Paul Eggert wrote:
> On 09/26/2010 07:56 AM, Duncan Moore wrote:
>
> > 1) --quote-filenames
> >     Filename quoting.
> I'd rather that troublsome file names always be quoted, instead of
> having an option that quotes them.  Diff already has too many options.
> The implementation can use the already-existing code to quote file
> names, taken from gnulib.

OK, I'll do that.

> > 2) --if-different
> >     File contents are assumed identical if the files have the same size
> > and timestamp.
> This makes sense, but the option name is poorly chosen.  How about
> --assume-same?

I was unhappy with the name too. I think --assume-same is better, but it 
doesn't convey the fact that it is conditional (on the timestamp and 
size being the same). But I'm happy to go with it, unless someone thinks 
of something better.

> > 3) --function-width=NUM
> >     Allow a user specified 'function width' greater than 40 characters.
> OK, but this should be column width, not character count, to allow for
> Chinese characters (which are typically two columns).  There's gnulib
> support for this.

OK, I'll have a look at that.

> > 4) -r
> >     Also shows the command performed for two files at the top level.
> I don't think POSIX would allow this change, and I don't see the need
> for it.

I sometimes find it useful in scripts to have the command options shown. 
Having a separate option for this behaviour seems a bit excessive 
though, so I'll scrub it.

> > 5) Help reformatted....
> > The help text has been reformatted, to make it easier to read (in fixed
> > width):
> The current formatting is to designed to look OK with varying-width
> fonts.  I'd rather that any reformatting continue to have that property.

OK

> > 6) --ignore-equivalent-strings=ERE
> >     Ignore equivalent strings, that is, strings at the same position in
> > both files, matching an extended regular expression.
> Not sure what this means.

This is explained in a subsequent message.

> > 7) --compare=PROPERTY_LIST
> >     File properties other than contents can be considered as a
> > difference - timestamps, mode etc.
> This sort of thing sounds useful.

Again this is explained in more detail in a subsequent message.