Re: [PATCH 1/3] color.c: Refactor color_output to use enums

[Jeff King <peff@peff.net>]

On Fri, Jan 10, 2020 at 10:05:45AM -0500, Eyal Soha wrote:

> Signed-off-by: Eyal Soha <shawarmakarma@gmail.com>
> ---
>  color.c | 28 +++++++++++++++++-----------
>  1 file changed, 17 insertions(+), 11 deletions(-)

The patch itself looks good, but it would be nice to have a commit
message explaining what's going on and why. Maybe something like:

  Using an enum reduces the number of magic numbers in the code. Note
  that we also use values that allow easier computations. For example,
  colors with type COLOR_ANSI now store the actual foreground code we
  expect (e.g., red=31) instead of an offset into our array, and we can
  switch between foreground/background for all types by adding an
  offset. That will help when we add new color types in a future patch.

> @@ -280,13 +286,13 @@ int color_parse_mem(const char *value, int value_len, char *dst)
>  			if (sep++)
>  				OUT(';');
>  			/* foreground colors are all in the 3x range */
> -			dst = color_output(dst, end - dst, &fg, '3');
> +			dst = color_output(dst, end - dst, &fg, 0);
>  		}
>  		if (!color_empty(&bg)) {
>  			if (sep++)
>  				OUT(';');
>  			/* background colors are all in the 4x range */
> -			dst = color_output(dst, end - dst, &bg, '4');
> +			dst = color_output(dst, end - dst, &bg, COLOR_BACKGROUND_OFFSET);
>  		}

Your original dropped the comments here, since we're not saying "3" or
"4" literally anymore. I could go either way, but I think I slightly
preferred dropping them. It might be even nicer if we had
COLOR_FOREGROUND_OFFSET = 0, which you could use instead of the bare
"0".

-Peff