diff --git a/src/testdir/test_options.vim b/src/testdir/test_options.vim
index d789a46..d640426 100644
--- a/src/testdir/test_options.vim
+++ b/src/testdir/test_options.vim
@@ -434,6 +434,7 @@
   set nomodifiable
   call assert_fails('set fileencoding=latin1', 'E21:')
   set modifiable&
+  call assert_fails('set t_#-&', 'E522:')
 endfunc
 
 func CheckWasSet(name)
@@ -946,6 +947,18 @@
   call assert_equal('gnewprg', &l:equalprg)
   call assert_equal('gnewprg', &equalprg)
   set equalprg&
+
+  " Test for setting the global/local value of a boolean option
+  setglobal autoread
+  setlocal noautoread
+  call assert_false(&autoread)
+  set autoread<
+  call assert_true(&autoread)
+  setglobal noautoread
+  setlocal autoread
+  setlocal autoread<
+  call assert_false(&autoread)
+  set autoread&
 endfunc
 
 " Test for incrementing, decrementing and multiplying a number option value
@@ -1121,4 +1134,22 @@
   call setenv('VIM_POSIX', saved_VIM_POSIX)
 endfunc
 
+" Test for setting an option to a Vi or Vim default
+func Test_opt_default()
+  set formatoptions&vi
+  call assert_equal('vt', &formatoptions)
+  set formatoptions&vim
+  call assert_equal('tcq', &formatoptions)
+endfunc
+
+" Test for the 'cmdheight' option
+func Test_cmdheight()
+  %bw!
+  let ht = &lines
+  set cmdheight=9999
+  call assert_equal(1, winheight(0))
+  call assert_equal(ht - 1, &cmdheight)
+  set cmdheight&
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab