Add test for overriding open
@@ -243,6 +243,8 @@ Open and include directives
==============================
open M
+open! M
+open ! M
include M
include t
include M.M
@@ -259,6 +261,8 @@ include M(M(M)).M(M).t
---
(compilation_unit
+ (open_statement (module_name))
+ (open_statement (module_name))
(open_statement (module_name))
(include_statement (module_name))
(include_statement (module_type_path (module_type_name)))
