add highlight method

Author: mattleong

lua/cosmic-ui/init.lua

@@ -4,4 +4,14 @@ M.rename = function(popup_opts, opts)
   return require('cosmic-ui.rename')(popup_opts, opts)
 end
 
+M.highlight = function(group, bg, fg, gui)
+  if gui ~= nil and gui ~= '' then
+    vim.api.nvim_command(('hi %s guibg=%s guifg=%s gui=%s'):format(group, bg, fg, gui))
+  elseif bg == nil then
+    vim.api.nvim_command(('hi %s guifg=%s'):format(group, fg))
+  else
+    vim.api.nvim_command(('hi %s guibg=%s guifg=%s'):format(group, bg, fg))
+  end
+end
+
 return M