refactor: defer_fn return type #37999

runtime/doc/lua.txt

@@ -1285,7 +1285,7 @@ vim.defer_fn({fn}, {timeout})                                 *vim.defer_fn()*
                    `fn`
 
     Return: ~
-        (`table`) timer luv timer object
+        (`uv.uv_timer_t`) timer luv timer object
 
                                                              *vim.deprecate()*
 vim.deprecate({name}, {alternative}, {version}, {plugin}, {backtrace})

runtime/lua/vim/_core/editor.lua

@@ -513,7 +513,7 @@ end
 --- safe to call.
 ---@param fn function Callback to call once `timeout` expires
 ---@param timeout integer Number of milliseconds to wait before calling `fn`
----@return table timer luv timer object
+---@return uv.uv_timer_t timer luv timer object
 function vim.defer_fn(fn, timeout)
   vim.validate('fn', fn, 'callable', true)
 

runtime/lua/vim/lsp.lua

@@ -1141,9 +1141,8 @@ api.nvim_create_autocmd('VimLeavePre', {
       client:stop(client.exit_timeout)
     end
 
-    local exit_warning_timer --- @type uv.uv_timer_t?
-    if max_timeout > min_warn_exit_timeout then
-      exit_warning_timer = vim.defer_fn(function()
+    local exit_warning_timer = max_timeout > min_warn_exit_timeout
+      and vim.defer_fn(function()
         api.nvim_echo({
           {
             string.format(
@@ -1154,7 +1153,6 @@ api.nvim_create_autocmd('VimLeavePre', {
           },
         }, true, {})
       end, min_warn_exit_timeout)
-    end
 
     vim.wait(max_timeout, function()
       return vim.iter(active_clients):all(function(client)