patch 9.0.0379: cleaning up after writefile() is a hassle Commit: https://github.com/vim/vim/commit/806a273f3c84ecd475913d901890bb1929be9a0a Author: Bram Moolenaar <Bram@vim.org> Date: Sun Sep 4 15:40:36 2022 +0100 patch 9.0.0379: cleaning up after writefile() is a hassle Problem: Cleaning up after writefile() is a hassle. Solution: Add the 'D' flag to defer deleting the written file. Very useful in tests.

" Vim filetype plugin
" Language:	Dockerfile
" Maintainer:   Honza Pokorny <http://honza.ca>
" Last Change:	2014 Aug 29

" Only do this when not done yet for this buffer
if exists("b:did_ftplugin")
  finish
endif

" Don't load another plugin for this buffer
let b:did_ftplugin = 1

let b:undo_ftplugin = "setl commentstring<"

setlocal commentstring=#\ %s