commit https://github.com/vim/vim/commit/d6a8d48587b2ff43c343fa365898576cc1e235ea Author: Bram Moolenaar <Bram@vim.org> Date: Wed Feb 10 20:32:20 2016 +0100 patch 7.4.1298 Problem: When the channel test fails in an unexpected way the server keeps running. Solution: Use try/catch. (Ozaki Kiichi)

" 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