patch 8.2.2994: various code is not fully tested

Problem:    Various code is not fully tested.
Solution:   Add a few more tests. (Yegappan Lakshmanan, closes #8378)
diff --git a/src/vim9compile.c b/src/vim9compile.c
index be8f304..12f41f1 100644
--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -454,7 +454,7 @@
     if (name[len] == '(' || (p[0] == '-' && p[1] == '>'))
     {
 	// Do not check for an internal function, since it might also be a
-	// valid command, such as ":split" versuse "split()".
+	// valid command, such as ":split" versus "split()".
 	// Skip "g:" before a function name.
 	is_global = (name[0] == 'g' && name[1] == ':');
 	return find_func(is_global ? name + 2 : name, is_global, cctx) != NULL;