Show current attached LSP count

templates/nvim/lua/lua-line.lua.j2

@@ -2,11 +2,17 @@
 
 local lualine = require('lualine');
 
--- TODO: show attached LSP count
+local function active_lsps()
+  local buffer = vim.api.nvim_get_current_buf()
+  local client_count = #vim.lsp.get_clients({ buffer = buffer })
+
+  return ('LSP: %d'):format(client_count)
+end
+
 lualine.setup {
   sections = {
     lualine_a = {'mode'},
-    lualine_b = {'branch', 'diff', 'diagnostics'},
+    lualine_b = {'branch', 'diff', 'diagnostics', active_lsps },
     lualine_c = {
       {
         'filename',