diff --git a/src/testdir/runtest.vim b/src/testdir/runtest.vim
index c094da0..559d5f8 100644
--- a/src/testdir/runtest.vim
+++ b/src/testdir/runtest.vim
@@ -42,6 +42,9 @@
   cquit
 endif
 
+" Common with all tests on all systems.
+source setup.vim
+
 " For consistency run all tests with 'nocompatible' set.
 " This also enables use of line continuation.
 set nocp viminfo+=nviminfo
@@ -55,9 +58,6 @@
 " Always use forward slashes.
 set shellslash
 
-" Make sure $HOME does not get read or written.
-let $HOME = '/does/not/exist'
-
 let s:srcdir = expand('%:p:h:h')
 
 " Prepare for calling test_garbagecollect_now().