add deprecation warning

Author: kyazdani42

lua/nvim-tree.lua

@@ -435,4 +435,27 @@ function M.setup(conf)
   M.on_enter(opts)
 end
 
+local out_config = {
+  "nvim_tree_disable_netrw",
+  "nvim_tree_hijack_netrw",
+  "nvim_tree_auto_open",
+  "nvim_tree_auto_close",
+  "nvim_tree_tab_open",
+  "nvim_tree_update_cwd",
+  "nvim_tree_hijack_cursor",
+  "nvim_tree_system_open_command",
+  "nvim_tree_system_open_command_args",
+  "nvim_tree_follow",
+  "nvim_tree_follow_update_path",
+}
+
+local x = vim.tbl_filter(function(v)
+  return vim.fn.exists('g:'..v) ~= 0
+end, out_config)
+
+if #x > 0 then
+  local msg = "following options are now set in the setup, please read the new documentation for the setup function: "
+  require'nvim-tree.utils'.echo_warning(msg..table.concat(x, " | "))
+end
+
 return M