patch 7.4.1785
Problem:    Regexp test fails on windows.
Solution:   set 'isprint' to the right value for testing.
diff --git a/src/testdir/test_regexp_utf8.vim b/src/testdir/test_regexp_utf8.vim
index cef2436..6247b30 100644
--- a/src/testdir/test_regexp_utf8.vim
+++ b/src/testdir/test_regexp_utf8.vim
@@ -35,6 +35,7 @@
 endfunc
 
 func s:classes_test()
+  set isprint=@,161-255
   call assert_equal('Motörhead', matchstr('Motörhead', '[[:print:]]\+'))
 
   let alphachars = ''