patch 8.2.0906: when setting 'termguicolors' SpellBad is no longer red Commit: https://github.com/vim/vim/commit/ea563cc22be043ff91dcbdf2878c3d1fd944e573 Author: Bram Moolenaar <Bram@vim.org> Date: Fri Jun 5 19:36:57 2020 +0200 patch 8.2.0906: when setting 'termguicolors' SpellBad is no longer red Problem: When setting 'termguicolors' SpellBad is no longer red. Solution: Only use the RGB guisp color for cterm when using the "underline" or "undercurl" attributes to avoid the background color to be cleared. Also make t_8u empty when the termresponse indicates a real xterm. (closes #6207)

#!/usr/bin/perl

use strict;
use warnings;

STDOUT->autoflush(1);

sub iswide
{
   my ( $cp ) = @_;
   return chr($cp) =~ m/\p{East_Asian_Width=Wide}|\p{East_Asian_Width=Fullwidth}/;
}

my ( $start, $end );
foreach my $cp ( 0 .. 0x1FFFF ) {
   iswide($cp) or next;

   if( defined $end and $end == $cp-1 ) {
      # extend the range
      $end = $cp;
      next;
   }

   # start a new range
   printf "  { %#04x, %#04x },\n", $start, $end if defined $start;

   $start = $end = $cp;
}

printf "  { %#04x, %#04x },\n", $start, $end if defined $start;