commit https://github.com/vim/vim/commit/1cee693b310e1494115a1677fac064941092e1bb Author: Bram Moolenaar <Bram@vim.org> Date: Thu Jun 9 22:17:22 2016 +0200 patch 7.4.1912 Problem: No test for using setqflist() on an older quickfix list. Solution: Add a couple of tests.

" Settings for test script execution
" Always use "COMMAND.COM", don't use the value of "$SHELL".
set shell=c:\COMMAND.COM shellquote= shellxquote= shellcmdflag=/c shellredir=>
" This is used only when the +eval feature is available.
if executable("cmd.exe")
   set shell=cmd.exe
endif