diff --git a/src/testdir/test_options.vim b/src/testdir/test_options.vim
index 5d2033a..0f2908f 100644
--- a/src/testdir/test_options.vim
+++ b/src/testdir/test_options.vim
@@ -332,3 +332,19 @@
   call assert_equal('', &indentexpr)
   bwipe!
 endfunc
+
+func Test_backupskip()
+  if has("mac")
+    call assert_match('/private/tmp/\*', &bsk)
+  elseif has("unix")
+    call assert_match('/tmp/\*', &bsk)
+  endif
+
+  let bskvalue = substitute(&bsk, '\\', '/', 'g')
+  for var in  ['$TEMPDIR', '$TMP', '$TEMP']
+    if exists(var)
+      let varvalue = substitute(expand(var), '\\', '/', 'g')
+      call assert_match(varvalue . '.\*', bskvalue)
+    endif
+  endfor
+endfunc