vim: Show icon in airline when black is disabled

home/.config/nvim/ftplugin/python.vim

@@ -1,3 +1,20 @@
 let b:black_disable = 0
 autocmd BufWritePre <buffer> if b:black_disable != 1 | execute 'silent Black' | endif
 map <Leader>b :let b:black_disable = (b:black_disable + 1) % 2<CR>
+
+" Show icon in airline when black is disabled
+" Adapted from https://github.com/ryanoasis/vim-devicons/blob/a5750c6507602a7238e1c87669c64a6d820a319d/plugin/webdevicons.vim#L567
+function! BlackIconStatus()
+  if &filetype ==# 'python' && b:black_disable == 1
+    return "  "
+  else
+    return ""
+  endif
+endfunction
+
+function! AirlineBlackIcon(...)
+  let w:airline_section_x = get(w:, 'airline_section_x', get(g:, 'airline_section_x', ''))
+  let w:airline_section_x .= '%{BlackIconStatus()}'
+endfunction
+
+call airline#add_statusline_func('AirlineBlackIcon')