diff --git a/src/testdir/test_netbeans.vim b/src/testdir/test_netbeans.vim
index 629c31a..ea845bd 100644
--- a/src/testdir/test_netbeans.vim
+++ b/src/testdir/test_netbeans.vim
@@ -845,6 +845,7 @@
   call writefile([], "Xnetbeans")
   let after =<< trim END
     source shared.vim
+    set cpo&vim
 
     func ReadXnetbeans()
       let l = readfile("Xnetbeans")