patch 9.1.0415: Some functions are not tested

Problem:  Some functions are not tested
Solution: Add a few more tests, fix a few minor problems
          (Yegappan Lakshmanan)

closes: #14789

Signed-off-by: Yegappan Lakshmanan <yegappan@yahoo.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_vim9_assign.vim b/src/testdir/test_vim9_assign.vim
index 7a72edc..bb08943 100644
--- a/src/testdir/test_vim9_assign.vim
+++ b/src/testdir/test_vim9_assign.vim
@@ -3687,4 +3687,16 @@
   v9.CheckScriptSuccess(lines)
 enddef
 
+" Test for overwriting a script-local function using the s: dictionary
+def Test_override_script_local_func()
+  var lines =<< trim END
+    vim9script
+    def MyFunc()
+    enddef
+    var d: dict<any> = s:
+    d.MyFunc = function('min')
+  END
+  v9.CheckScriptFailure(lines, 'E705: Variable name conflicts with existing function: MyFunc', 5)
+enddef
+
 " vim: ts=8 sw=2 sts=2 expandtab tw=80 fdm=marker