vim/neovim support

[anakojm]

even if your terminal correctly supports ucsur sp, vim/neovim will not. however, even if your terminal does not support ucsur sp, but vim/neovim does, everything will work fine inside vim/neovim (afaics)
here is a simple patch to neovim that should work with vim too that makes ucsur sp double width:

diff --git a/src/nvim/mbyte.c b/src/nvim/mbyte.c
index 4d4c299423..28cc3c962f 100644
--- a/src/nvim/mbyte.c
+++ b/src/nvim/mbyte.c
@@ -458,6 +458,10 @@ int utf_char2cells(int c)
     return 1;
   }

+  if ((c >= 0xF1900ul) && (c <= 0xF19FFul) && !((c >= 0xF1990ul) && (c <= 0xF199Bul) && (c != 0xF1993ul))) {
+    return 2;
+  }
+
   if (!vim_isprintc(c)) {
     assert(c <= 0xFFFF);
     // unprintable is displayed either as <xx> or <xxxx>

(unlike this repo’s wcwidth, start and end of cartouche are not set as doublewidth, as it looks weird in kitty otherwise)

you can then compile normally

with the terminal not supporting double width ucsur sp:

with both supporting double width ucsur sp:

the difference seems to only be visual

there are also patches/compilation flags for vim/neovim and other programs (alacritty, iterm2, zsh, tmux) to use the system’s wcwidth https://emonkak.pages.dev/articles/wcwidth/ which, with the LD_PRELOAD env variable like used in this repo would make ucsur sp work directly (haven’t tested it though)

[trickyni]

vim.fn.setcellwidths({
  { 0xF1900, 0xF1989, 2 },
  { 0xF1990, 0xF1991, 1 },
  { 0xF1992, 0xF1996, 2 },
  { 0xF1997, 0xF1998, 1 },
  { 0xF1999, 0xF19FF, 2 },
})

Can be added into init.lua to force some of the glyphs to take up two cells by default. In this example, I'm asking all sitelen pona glyphs to do so with the exception of the cartouche and long glyph symbols.

[anakojm]

thanks a lot for that usefull function that i had totally missed. here is what it looks like with this code in my neovim config:

vim.fn.setcellwidths({{0xF1900, 0xF198F, 2}, {0xF1993, 0xF1993, 2}, {0xF19A0, 0xF19FF, 2}})

(and with the terminal not supporting double width ucsur sp)

seems like recompiling neovim is completely unnecessary!