Re: Fwd: Add support for axiterm colors in parse_color

>
> On Thu, Jan 09, 2020 at 07:20:09PM -0500, Eyal Soha wrote:
>
> > > That said, I'm not entirely opposed to having more human-readable
> > > aliases. I'm not sure if it's worth using the 16-color version (e.g.,
> > > "ESC[91m" versus the 256-color version "ESC[38;5;9m"). It's possible it
> > > would be compatible with more terminals, and it is slightly fewer bytes.
> >
> > My motivation for this patch was to fix the github workflow log output
> > that doesn't support 8bit colors properly.  Only the "ANSI" colors
> > 0-15 worked.  None of the 8-bit colors worked except for 30-37, 40-47,
> > 90-97, and 100-107, which matched the ANSI colors.  That is a very
> > broken color scheme!  But that's how it displayed.
>
> That makes sense. I'm not too surprised to see a terminal that supports
> one but not the other.
>
> But I wonder if there are ones that go the other way around: supporting
> 256-color mode but not ANSI 90-97, etc. I doubt it, but I think it would
> be nice to split that change out into a separate commit in case we do
> run into problems.
>
> > Done.  Here's a new patch!
>
> Thanks. The content here is looking pretty good (though I have a few
> comments below).
>
> Can you also format it as described in Documentation/SubmittingPatches
> and re-send? In particular, it needs a regular commit message and your
> signoff.
>
> > +enum {
> > +       COLOR_BACKGROUND_OFFSET = 10,
> > +       COLOR_FOREGROUND_ANSI = 30,
> > +       COLOR_FOREGROUND_RGB = 38,
> > +       COLOR_FOREGROUND_256 = 38,
> > +       COLOR_FOREGROUND_BRIGHT_ANSI = 90,
> > +};
>
> The split in this enum mostly makes sense to me. It changes the meaning
> of "value" for COLOR_ANSI, but this is all local to color.c, so your
> changes to output_color() are all that's needed.
>
> It might be easier to follow the patch if switching to this enum came in
> a separate preparatory patch.
>
> > @@ -92,7 +100,13 @@ static int parse_color(struct color *out, const
> > char *name, int len)
> >         for (i = 0; i < ARRAY_SIZE(color_names); i++) {
> >                 if (match_word(name, len, color_names[i])) {
> >                         out->type = COLOR_ANSI;
> > -                       out->value = i;
> > +                       out->value = i + COLOR_FOREGROUND_ANSI;
> > +                       return 0;
> > +               }
> > +               if (*name == '+' &&
> > +                   match_word(name+1, len-1, color_names[i])) {
> > +                       out->type = COLOR_ANSI;
> > +                       out->value = i + COLOR_FOREGROUND_BRIGHT_ANSI;
> >                         return 0;
> >                 }
>
> It would be slightly simpler and more efficient handle the "+" outside
> the loop, like:
>
>   int offset = COLOR_FOREGROUND_ANSI;
>   if (*name == '+') {
>           offset = COLOR_FOREGROUND_BRIGHT_ANSI;
>           name++;
>           len--;
>   }
>
> and then in the loop just set "out->value = i + offset".
>
> You'd probably want to hoist this out to a separate function since
> "name" needs to be unchanged in the later part of the function.
>
> I dunno. It's almost certainly an unmeasurable micro-optimization, but
> somehow the flow of it seems simpler to me.
>
> I also wondered if we'd want English aliases like "brightred" that some
> other systems use. It would be easy to add that to the check I showed
> above without having to repeat as much.
>
> > @@ -109,10 +123,15 @@ static int parse_color(struct color *out, const
> > char *name, int len)
> >                 else if (val < 0) {
> >                         out->type = COLOR_NORMAL;
> >                         return 0;
> > -               /* Rewrite low numbers as more-portable standard colors. */
> > +               /* Rewrite 0-7 as more-portable standard colors. */
> >                 } else if (val < 8) {
> >                         out->type = COLOR_ANSI;
> > -                       out->value = val;
> > +                       out->value = val + COLOR_FOREGROUND_ANSI;
> > +                       return 0;
> > +               /* Rewrite 8-15 as more-portable aixterm colors. */
> > +               } else if (val < 16) {
> > +                       out->type = COLOR_ANSI;
> > +                       out->value = val - 8 + COLOR_FOREGROUND_BRIGHT_ANSI;
>
> And I think this 8-15 handling might want to be a separate commit on
> top, just because it's possible it might regress some cases (though
> again, I do doubt it).
>
> >         case COLOR_256:
> > -               out += xsnprintf(out, len, "%c8;5;%d", type, c->value);
> > +         out += xsnprintf(out, len, "%d;5;%d", COLOR_FOREGROUND_256 + offset,
> > +                          c->value);
>
> Looks like some unwanted tab/space conversion (here and elsewhere).
>
> > +test_expect_success 'axiterm bright fg color' '
> > +       color "+red" "[91m"
>
> s/axi/aix/ (here and below).
>
> > +test_expect_success '8-15 are aliases for aixterm color names' '
> > +       color "12 13" "[94;105m"
>
> Makes sense.
>
> -Peff