vim-patch:ba3a5a7: runtime(sh): properly delete shell commands in syntax file

closes: vim/vim#17785

ba3a5a7372

Co-authored-by: Christoffer Aasted <chr.aasted@gmail.com>

runtime/syntax/sh.vim

@@ -3,7 +3,7 @@
 " Maintainer:		This runtime file is looking for a new maintainer.
 " Previous Maintainers:	Charles E. Campbell
 " 		Lennart Schultz <Lennart.Schultz@ecmwf.int>
-" Last Change:		2024 Mar 04 by Vim Project
+" Last Change:		2024 Mar 04 by Vim Project {{{1
 "		2024 Nov 03 by Aliaksei Budavei <0x000c70 AT gmail DOT com> (improved bracket expressions, #15941)
 "		2025 Jan 06 add $PS0 to bashSpecialVariables (#16394)
 "		2025 Jan 18 add bash coproc, remove duplicate syn keywords (#16467)
@@ -16,6 +16,8 @@
 "		2025 May 10 improve wildcard character class lists
 "		2025 May 21 improve supported KornShell features
 "		2025 Jun 16 change how sh_fold_enabled is reset (#17557)
+"		2025 Jul 18 properly delete :commands #17785
+" }}}
 " Version:		208
 " Former URL:		http://www.drchip.org/astronaut/vim/index.html#SYNTAX_SH
 " For options and settings, please use:      :help ft-sh-syntax
@@ -174,9 +176,15 @@ endif
 
 " Set up folding commands for shell {{{1
 " =================================
-sil! delc ShFoldFunctions
-sil! delc ShFoldHereDoc
-sil! delc ShFoldIfDoFor
+if exists(":ShFoldFunctions") == 2
+  delc ShFoldFunctions
+endif
+if exists(":ShFoldIfHereDoc") == 2
+  delc ShFoldHereDoc
+endif
+if exists(":ShFoldIfDoFor") == 2
+  delc ShFoldIfDoFor
+endif
 if s:sh_fold_functions
  com! -nargs=* ShFoldFunctions <args> fold
 else