vim-patch:7.4.2031 (#5955)

Problem:    The list_lbr_utf8 test fails if ~/.vim/syntax/c.vim sets
            'textwidth' to a non-zero value. (Oyvind A. Holm)
Solution:   Add a setup.vim file that sets 'runtimepath' and $HOME to a safe
            value. (partly by Christian Brabandt, closes vim/vim#912)

89b10421ca

src/nvim/testdir/runtest.vim

@@ -39,6 +39,9 @@ if &lines < 24 || &columns < 80
   cquit
 endif
 
+" Common with all tests on all systems.
+source setup.vim
+
 " This also enables use of line continuation.
 set viminfo+=nviminfo
 
@@ -59,9 +62,6 @@ lang mess C
 " Always use forward slashes.
 set shellslash
 
-" Make sure $HOME does not get read or written.
-let $HOME = '/does/not/exist'
-
 " Align with vim defaults.
 set directory^=.
 set nohidden