commit https://github.com/vim/vim/commit/04c4ce650f9e533cd35b2aa6803f4d354d3ec7aa Author: Bram Moolenaar <Bram@vim.org> Date: Thu Sep 1 15:45:58 2016 +0200 patch 7.4.2299 Problem: QuickFixCmdPre and QuickFixCmdPost autocommands are not always triggered. Solution: Also trigger on ":expr", ":cbuffer", etc. (Yegappan Lakshmanan)

" Common preparations for running tests.

" Make sure 'runtimepath' and 'packpath' does not include $HOME.
set rtp=$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after
if has('packages')
  let &packpath = &rtp
endif

" Only when the +eval feature is present. 
if 1
  " Make sure $HOME does not get read or written.
  let $HOME = '/does/not/exist'
endif