Missing Unicode symbols (maybe Powerline symbols issue?)

[wbthomason]

This might be related to #8, but, as the below screenshots show, I'm seeing an odd subset of symbols missing in FVim vs. terminal Neovim.

Here's FVIM:

And here's terminal Neovim (in Kitty):

You'll notice that the symbols for ALE on the sign bar aren't rendered correctly, nor are some of the statusline symbols, nor the symbols for coc.nvim.

The relevant part of my ginit.vim is

  set guifont=Fira\ Code\ Retina:h11
  FVimFontAntialias v:true
  FVimFontAutohint v:true
  FVimFontSubpixel v:true
  FVimFontLcdRender v:true
  FVimFontHintLevel 'full'
  FVimFontAutoSnap v:true
  nnoremap <silent> <C-ScrollWheelUp> :set guifont=+<CR>
  nnoremap <silent> <C-ScrollWheelDown> :set guifont=-<CR>

my Kitty config uses the following fonts

font_family      FiraCode-Retina
bold_font        Fira Code Bold
italic_font      Roboto Mono Italic Nerd Font Complete Mono
bold_italic_font Roboto Mono Bold Italic Nerd Font Complete Mono
font_size 10.0

and I'm on Arch Linux with the latest AUR FVim and Neovim built from master 12/12/2019.

The additional difference in the FVim screenshot - the coc.nvim documentation floating window showing vs. in terminal Neovim - seems to be due to some weird interaction with FVim and coc.nvim. I sometimes see the first item selected and confirmed instantly for me in FVim whereas it is not in Neovim. This seems like a separate issue, though.

The specific symbols not rendering are:

• 🗙, ➤ in the sign bar
• ⏺ in the statusline at the lower left-hand corner - I suspect this might be due to a width issue, as the very similar symbol ● renders correctly slightly to the right in the statusline.
• The following list of symbols in coc.nvim (taken from my coc-config.json):

  "suggest.completionItemKindLabels": {
    "function": "\uf794",
    "method": "\uf6a6",
    "variable": "\uf71b",
    "constant": "\uf8ff",
    "struct": "\ufb44",
    "class": "\uf0e8",
    "interface": "\ufa52",
    "text": "\ue612",
    "enum": "\uf435",
    "enumMember": "\uf02b",
    "module": "\uf668",
    "color": "\ue22b",
    "property": "\ufab6",
    "field": "\uf93d",
    "unit": "\uf475",
    "file": "\uf471",
    "value": "\uf8a3",
    "event": "\ufacd",
    "folder": "\uf115",
    "keyword": "\uf893",
    "snippet": "\uf64d",
    "operator": "\uf915",
    "reference": "\uf87a",
    "typeParameter": "\uf278",
    "default": "\uf29c"
  }

I'm happy to perform more debugging/supply more information to help, but I'm not quite sure what to check next. Please let me know how I can help with this issue! Thanks!

[wbthomason]

Hmm. The ● symbol now isn't showing up, after I rebuilt FVim from the AUR...

[yatli]

Here are the symbol codepoint ranges:

fvim/wcwidth.fs

Lines 491 to 521 in 83a7798

	let Powerline = [|
	(0xe0a0, 0xe0a2) // Powerline Symbols
	(0xe0a3, 0xe0a3) // Powerline Extra Symbols
	(0xe0b0, 0xe0b3) // Powerline Symbols
	(0xe0b4, 0xe0c8) // Powerline Extra Symbols
	(0xe0ca, 0xe0ca) // Powerline Extra Symbols
	(0xe0cc, 0xe0d4) // Powerline Extra Symbols
	|]
	// The complete set is recorded in nerdfont.txt
	let NerdFont = [|
	(0x23fb, 0x23fe) // Power Symbols
	(0x2665, 0x2665) // Octicons
	(0x26a1, 0x26a1) // Octicons
	(0x2b58, 0x2b58) // Power Symbols
	(0xe000, 0xe00a) // Pomicons
	(0xe0a0, 0xe0a2) // Powerline Symbols
	(0xe0a3, 0xe0a3) // Powerline Extra Symbols
	(0xe0b0, 0xe0b3) // Powerline Symbols
	(0xe0b4, 0xe0c8) // Powerline Extra Symbols
	(0xe0ca, 0xe0ca) // Powerline Extra Symbols
	(0xe0cc, 0xe0d4) // Powerline Extra Symbols
	(0xe200, 0xe2a9) // Font Awesome Extension
	(0xe300, 0xe3e3) // Weather
	(0xe5fa, 0xe62e) // Custom + Seti
	(0xe700, 0xe7c5) // Devicons
	(0xf000, 0xf2e0) // Font Awesome
	(0xf300, 0xf31c) // Font Logos (Font Linux)
	(0xf400, 0xf4a8) // Octicons
	(0xf500, 0xfd46) // Material
	|]

Could you please check if the symbols can be displayed when you insert the missing range?
Also, are these codepoints documented somewhere? Looks like some kind of extension that I was not aware of.

[yatli]

Also fyi, to leverage the popup symbols:

if exists("g:fvim_loaded")
    call coc#config('suggest.completionItemKindLabels', {
                \ "text": "t",
                \ "method": ":",
                \ "function": "f",
                \ "constructor": "c",
                \ "field": ".",
                \ "variable": "v",
                \ "class": "C",
                \ "interface": "I",
                \ "module": "M",
                \ "property": "p",
                \ "unit": "U",
                \ "value": "l",
                \ "enum": "E",
                \ "keyword": "k",
                \ "snippet": "s",
                \ "color": "K",
                \ "file": "F",
                \ "reference": "r",
                \ "folder": "d",
                \ "enumMember": "m",
                \ "constant": "0",
                \ "struct": "S",
                \ "event": "e",
                \ "operator": "o",
                \ "typeParameter": "T"
                \ })
endif

(mainly suggest.completionItemKindLabels)

[wbthomason]

Thanks for the tip about coc.nvim; I was already setting suggest.completionItemKindLabels, but did not know that I couldn't set it to custom symbols or that setting the values you suggest would cause FVim to render fancier symbols than the basic characters. Perhaps this could be added to the README or wiki?

I inserted the following line

(0x23fa, 0x1f5d9)

(which, according to http://unicode.scarfboy.com/?s=%F0%9F%97%99%E2%9E%A4%E2%97%8F%E2%8F%BA, encompasses the range for the characters I mentioned in the statusline and sign column)

in the NerdFont array and recompiled (from the release commit used by the AUR FVim). I did not observe any difference in character rendering; the same characters rendered incorrectly. I tried building from master but haven't been able to get it to compile on my machine (I get an error about not being able to target .NET Core 3.0).

If that's not what you meant by inserting the missing range, please let me know and I can try again.

I unfortunately don't know of anywhere that documents those codepoints; as far as I was aware, they were ordinary Unicode symbols. I found them in a variety of docs and vim configs over a while; I'm afraid I don't know specifically where each came from originally.

[wbthomason]

Ah, I figured out that the Arch dotnet-sdk package is woefully out of date and installed .NET Core 3.1. That let me build from master. Sadly, this did not fix anything; I still observe the original rendering problems.

[yatli]

Let's use this thread as the primary progress tracker for unicode fallback calculation.

[wbthomason]

@yatli There's been some relevant discussion to my original question here over at neovide/neovide#75.

Specifically:

• [Linux] Question about fallback fonts neovide/neovide#75 (comment) identifies the codepoints causing errors (which I believe were the same for FVim)
• [Linux] Question about fallback fonts neovide/neovide#75 (comment) and [Linux] Question about fallback fonts neovide/neovide#75 (comment) identify the fonts for the symbols

[yatli]

Thanks for the info!

[yatli]

Okay regular revisit on this issue:

🗙  1F5D9  missing in both FVim calculation and NerdFont
➤  27A4  missing in both FVim calculation and NerdFont
⏺ 23FA  works, but too wide (can't fix this one at the moment..)

[jdhao]

More airline characters that can not be shown by fvim (nvim-qt shows them correctly using the same Hack font)

☰ (U+2630)
Ꞩ (U+A7A8)
Ɇ (U+0246)
⎇ (U+2387)
☲ (U+2632)

[yatli]

@jdhao @wbthomason and also @Kethku, you may be interested in this:
https://github.com/yatli/fvim/blob/master/wcwidth.fsx

[motorto]

Adding to this making sure that the problem is not my config:

As you can see from the pictures the unicode for endLine is not working properly.

vim.opt.listchars="tab:» ,eol:↲,nbsp:␣,precedes:<,extends:>,trail:·,conceal:┊"

if exists('g:fvim_loaded')
	" good old 'set guifont' compatibility with HiDPI hints...
	if g:fvim_os == 'windows' || g:fvim_render_scale > 1.0
		set guifont=FantasqueSansMono\ Nerd\ Font\ Mono:h14
	else
		set guifont=FantasqueSansMono\ Nerd\ Font\ Mono:h28
	endif
endif