patch 8.2.0764: Vim9: assigning to option not fully tested

Problem:    Vim9: assigning to option not fully tested.
Solution:   Add more test cases. Allow using any type for assignment.
diff --git a/src/testdir/test_vim9_script.vim b/src/testdir/test_vim9_script.vim
index fd1dbc8..4284aad 100644
--- a/src/testdir/test_vim9_script.vim
+++ b/src/testdir/test_vim9_script.vim
@@ -14,6 +14,8 @@
 let g:existing = 'yes'
 let g:inc_counter = 1
 let $SOME_ENV_VAR = 'some'
+let g:alist = [7]
+let g:astring = 'text'
 
 def Test_assignment()
   let bool1: bool = true
@@ -95,7 +97,12 @@
   assert_equal(2, &ts)
   call CheckDefFailure(['&notex += 3'], 'E113:')
   call CheckDefFailure(['&ts ..= "xxx"'], 'E1019:')
+  call CheckDefFailure(['&ts = [7]'], 'E1013:')
+  call CheckDefExecFailure(['&ts = g:alist'], 'E1029: Expected number but got list')
+  call CheckDefFailure(['&ts = "xx"'], 'E1013:')
+  call CheckDefExecFailure(['&ts = g:astring'], 'E1029: Expected number but got string')
   call CheckDefFailure(['&path += 3'], 'E1013:')
+  call CheckDefExecFailure(['&bs = "asdf"'], 'E474:')
   # test freeing ISN_STOREOPT
   call CheckDefFailure(['&ts = 3', 'let asdf'], 'E1022:')
   &ts = 8