patch 8.0.1243: no test for what 8.0.1227 fixes

Problem:    No test for what 8.0.1227 fixes.
Solution:   Add a test that triggers the problem. (Christian Brabandt)
diff --git a/src/testdir/test_normal.vim b/src/testdir/test_normal.vim
index f6b1a43..90033c0 100644
--- a/src/testdir/test_normal.vim
+++ b/src/testdir/test_normal.vim
@@ -1208,6 +1208,13 @@
   call assert_match("Word 'goood' added to ./Xspellfile2.add", a)
   call assert_equal('goood', cnt[0])
 
+  " Test for :spellgood!
+  let temp = execute(':spe!0/0')
+  call assert_match('Invalid region', temp)
+  let spellfile = matchstr(temp, 'Invalid region nr in \zs.*\ze line \d: 0')
+  call assert_equal(['# goood', '# goood/!', '#oood', '0/0'], readfile(spellfile))
+  call delete(spellfile)
+
   " clean up
   exe "lang" oldlang
   call delete("./Xspellfile.add")