Add test to emulate method through field

Author: khvzak

tests/userdata.rs

@@ -525,6 +525,11 @@ fn test_fields() -> Result<()> {
                 Ok(())
             });
 
+            // Field that emulates method
+            fields.add_field_function_get("val_fget", |lua, ud| {
+                lua.create_function(move |_, ()| Ok(ud.borrow::<MyUserData>()?.0))
+            });
+
             // Use userdata "uservalue" storage
             fields.add_field_function_get("uval", |_, ud| ud.user_value::<Option<String>>());
             fields.add_field_function_set("uval", |_, ud, s: Option<String>| ud.set_user_value(s));
@@ -537,6 +542,10 @@ fn test_fields() -> Result<()> {
                 })
             })
         }
+
+        fn add_methods<M: UserDataMethods<Self>>(methods: &mut M) {
+            methods.add_method("dummy", |_, _, ()| Ok(()));
+        }
     }
 
     globals.set("ud", MyUserData(7))?;
@@ -546,6 +555,7 @@ fn test_fields() -> Result<()> {
         assert(ud.val == 7)
         ud.val = 10
         assert(ud.val == 10)
+        assert(ud:val_fget() == 10)
 
         assert(ud.uval == nil)
         ud.uval = "hello"