Commit: runtime(optwin): Fix E94 when searching for the option-window

[Christian Brabandt]

runtime(optwin): Fix E94 when searching for the option-window

Commit: https://github.com/vim/vim/commit/3be4ad76df92086e29c3fcf5e6a25f285b6e188f
Author: RestorerZ <rest...@mail2k.ru>
Date: Fri Aug 8 12:37:06 2025 +0200

runtime(optwin): Fix E94 when searching for the option-window

Problem: When the parameter debug=msg is set and the command :option is
entered, error E94 will be displayed.
Solution: Add a check for the existence of the buffer before getting the
buffer number “option-window”.

Reproduce:

vim --clean -c "set debug=msg" -c "option"

Error detected while processing command line..script D:\Programs\Vim im91\optwin.vim:
line 9: E94: No matching buffer for option-window

closes: #17927

Signed-off-by: RestorerZ <rest...@mail2k.ru>
Signed-off-by: Christian Brabandt <c...@256bit.org>

diff --git a/runtime/optwin.vim b/runtime/optwin.vim
index 47e165f45..26c80e5ce 100644
--- a/runtime/optwin.vim
+++ b/runtime/optwin.vim
@@ -1,11 +1,11 @@
" These commands create the option window.
"
" Maintainer: The Vim Project <https://github.com/vim/vim>
-" Last Change: 2025 Jul 25
+" Last Change: 2025 Aug 07
" Former Maintainer: Bram Moolenaar <Br...@vim.org>

" If there already is an option window, jump to that one.
-let buf = bufnr('option-window')
+let buf = bufexists('option-window') ? bufnr('option-window') : -1
if buf >= 0
let winids = win_findbuf(buf)
if len(winids) > 0