From 72fe59ffaaedbcfcb74cc13c7fc85d2f359d639f Mon Sep 17 00:00:00 2001
From: "Kenneth Benzie (Benie)" <benie@infektor.net>
Date: Thu, 4 Apr 2019 16:53:46 +0100
Subject: [PATCH] Only invoke last change substitution in help files

Previously the `autocmd` to replace the date on the first line if `Last
change: ` was present resulted in the cursor being moved in non `help`
filetypes due to the substitution failing. Now the substitution is only
attempted if the current file is a `help` file.
---
 autoload/do.vim     | 8 ++++++++
 plugin/autocmds.vim | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/autoload/do.vim b/autoload/do.vim
index aaaaedd..c0f39be 100644
--- a/autoload/do.vim
+++ b/autoload/do.vim
@@ -78,3 +78,11 @@ function! do#debug(...)
   endfor
   exec l:command
 endfunction
+
+function! do#last_change()
+  if &filetype ==# 'help'
+    " vint: next-line -ProhibitCommandRelyOnUser -ProhibitCommandWithUnintendedSideEffect
+    1s/Last change: \zs.*$/\=strftime('%Y %b %d')/e
+    norm!``
+  endif
+endfunction
diff --git a/plugin/autocmds.vim b/plugin/autocmds.vim
index 552e119..8b16cfb 100644
--- a/plugin/autocmds.vim
+++ b/plugin/autocmds.vim
@@ -9,7 +9,7 @@ augroup benieAugroup
   au FileType * call matchadd('Todo', '^\(<<<<<<<\||||||||\|=======\|>>>>>>>\)\s\ze.*$')
 
   " Update `Last change: <date>` on write then jump back previous position
-  au BufWritePost *.txt 1s/Last change: \zs.*$/\=strftime('%Y %b %d')/e|norm!``
+  au BufWritePost *.txt silent! call do#last_change()
 
   " Read template into buffer then send line 1 to the black hold register
   au BufNewFile todo.md read ~/.vim/templates/skeleton.todo.md | 1delete _