commit https://github.com/vim/vim/commit/385111bd86e0b38667879c3e89506ca1ae98e1df Author: Bram Moolenaar <Bram@vim.org> Date: Sat Mar 12 19:23:00 2016 +0100 patch 7.4.1547 Problem: Getting a cterm highlight attribute that is not set results in the string "-1". Solution: Return an empty string. (Taro Muraoka)

" Vim support file to switch off loading indent files for file types
"
" Maintainer:	Bram Moolenaar <Bram@vim.org>
" Last Change:	2001 Jun 11

if exists("did_indent_on")
  unlet did_indent_on
endif

" Remove all autocommands in the filetypeindent group
silent! au! filetypeindent *