diff --git a/src/testdir/test_functions.vim b/src/testdir/test_functions.vim
index 45b997f..b816125 100644
--- a/src/testdir/test_functions.vim
+++ b/src/testdir/test_functions.vim
@@ -339,6 +339,8 @@
   call assert_equal('Xlink2', resolve('Xlink1'))
   call assert_equal('./Xlink2', resolve('./Xlink1'))
   call delete('Xlink1')
+
+  call assert_equal('/', resolve('/'))
 endfunc
 
 func s:normalize_fname(fname)