apply the optimization

Author: bobzhang

jscomp/core/lam_compile_external_obj.ml

@@ -104,7 +104,7 @@ let assemble_obj_args (labels : External_arg_spec.obj_params)  (args : J.express
       (Ext_list.flat_map assignment (fun 
         ((xlabel : External_arg_spec.obj_param), (arg  : J.expression )) -> 
       match xlabel with 
-      | {obj_arg_label = Obj_optional {name = label} } -> 
+      | {obj_arg_label = Obj_optional {name = label;for_sure_no_nested_option} } -> 
         (* Need make sure whether assignment is effectful or not
           to avoid code duplication
         *)
@@ -114,7 +114,7 @@ let assemble_obj_args (labels : External_arg_spec.obj_params)  (args : J.express
             Lam_compile_external_call.ocaml_to_js_eff 
             ~arg_label:
              Arg_empty ~arg_type:xlabel.obj_arg_type 
-              (Js_of_lam_option.val_from_option arg) in 
+              (if for_sure_no_nested_option then arg else Js_of_lam_option.val_from_option arg) in 
           begin match acc with 
           | Splice1 v  ->                         
             [S.if_ (Js_of_lam_option.is_not_none arg )
@@ -134,7 +134,7 @@ let assemble_obj_args (labels : External_arg_spec.obj_params)  (args : J.express
             ~arg_label:
              Arg_empty
              ~arg_type:xlabel.obj_arg_type             
-              (Js_of_lam_option.val_from_option arg) in 
+              (if for_sure_no_nested_option then arg else Js_of_lam_option.val_from_option arg) in 
           begin match acc with 
           | Splice1 v  ->        
             st ::  

jscomp/frontend/ast_external_process.ml

@@ -492,17 +492,22 @@ let process_obj
                    param_type::arg_types, result_types
                  | Nothing ->
                    let s = (Lam_methname.translate  name) in
-                   {obj_arg_label = External_arg_spec.optional s; obj_arg_type},
+                   let for_sure_not_nested = 
+                     match ty.ptyp_desc with 
+                     | Ptyp_constr({txt = Lident txt;_}, []) ->
+                       Ast_core_type.is_builtin_rank0_type txt
+                     | _ -> false in 
+                   {obj_arg_label = External_arg_spec.optional for_sure_not_nested s; obj_arg_type},
                    param_type :: arg_types,
                    ( Parsetree.Otag ({Asttypes.txt = name; loc}, [], Ast_comb.to_undefined_type loc ty) ::  result_types)
                  | Int _  ->
                    let s = Lam_methname.translate  name in
-                   {obj_arg_label = External_arg_spec.optional s ; obj_arg_type },
+                   {obj_arg_label = External_arg_spec.optional true s ; obj_arg_type },
                    param_type :: arg_types,
                    (Otag ({Asttypes.txt = name; loc}, [], Ast_comb.to_undefined_type loc @@ Ast_literal.type_int ~loc ()) :: result_types)
                  | Poly_var_string _ ->
                    let s = Lam_methname.translate  name in
-                   {obj_arg_label = External_arg_spec.optional s ; obj_arg_type },
+                   {obj_arg_label = External_arg_spec.optional true s ; obj_arg_type },
                    param_type::arg_types,
                    (Otag ({Asttypes.txt = name; loc}, [], Ast_comb.to_undefined_type loc @@ Ast_literal.type_string ~loc ()) :: result_types)
                  | Arg_cst _
@@ -1020,7 +1025,7 @@ let pval_prim_of_option_labels
           let label_name = Lam_methname.translate  p.txt in
           let obj_arg_label =
             if is_option then
-              External_arg_spec.optional label_name
+              External_arg_spec.optional false label_name
             else External_arg_spec.obj_label label_name 
           in
           {obj_arg_type = Nothing ;