upgrade ppxlib to 0.36 / handle Ptyp_open

ppx/native/common/ppx_deriving_tools.ml

@@ -4,11 +4,35 @@ open Ast_builder.Default
 open StdLabels
 open Expansion_helpers
 
+module Lid = struct
+  let flatten =
+    let rec flat accu = function
+      | Lident s -> s :: accu
+      | Ldot (lid, s) -> flat (s :: accu) lid
+      | Lapply (_, _) -> failwith "Longident.flat"
+    in
+    fun lid -> flat [] lid
+
+  let unflatten l =
+    match l with
+    | [] -> None
+    | hd :: tl ->
+        Some
+          (List.fold_left
+             ~f:(fun p s -> Ldot (p, s))
+             ~init:(Lident hd) tl)
+end
+
 let not_supported ~loc what =
   Location.raise_errorf ~loc "%s are not supported" what
 
 let map_loc f a_loc = { a_loc with txt = f a_loc.txt }
 
+let lident_with_optional_open ?opn label =
+  match opn with
+  | Some { txt = lid; _ } -> Longident.Ldot (lid, label)
+  | None -> lident label
+
 let gen_bindings ~loc prefix n =
   List.split
     (List.init ~len:n ~f:(fun i ->
@@ -129,13 +153,14 @@ module Schema = struct
     | Rinherit _ ->
         not_supported ~loc:field.prf_loc "this polyvariant inherit"
 
-  let repr_core_type ty =
+  let rec repr_core_type ty =
     let loc = ty.ptyp_loc in
     match ty.ptyp_desc with
     | Ptyp_tuple ts -> `Ptyp_tuple ts
     | Ptyp_constr (id, ts) -> `Ptyp_constr (id, ts)
     | Ptyp_var txt -> `Ptyp_var { txt; loc = ty.ptyp_loc }
     | Ptyp_variant (fs, Closed, None) -> `Ptyp_variant fs
+    | Ptyp_open (id, ct) -> `Ptyp_open (id, repr_core_type ct)
     | Ptyp_variant _ -> not_supported ~loc "non closed polyvariants"
     | Ptyp_arrow _ -> not_supported ~loc "function types"
     | Ptyp_any -> not_supported ~loc "type placeholders"
@@ -246,11 +271,31 @@ module Schema = struct
 
       method private derive_of_core_type' t =
         let loc = t.ptyp_loc in
-        match repr_core_type t with
+        self#derive_of_core_type_repr ~loc t (repr_core_type t)
+
+      method private derive_of_core_type_repr ?opn ~loc t repr =
+        match repr with
         | `Ptyp_tuple ts -> As_fun (self#derive_of_tuple t ts)
         | `Ptyp_var label ->
-            As_val (ederiver self#name (map_loc lident label))
+            As_val
+              (ederiver self#name
+                 (map_loc (lident_with_optional_open ?opn) label))
+        | `Ptyp_open (_, `Ptyp_open _) -> assert false
+        | `Ptyp_open (lid, ct) ->
+            self#derive_of_core_type_repr ~opn:lid ~loc t ct
         | `Ptyp_constr (id, ts) ->
+            let id =
+              match opn with
+              | Some { txt = lid; loc } ->
+                  {
+                    txt =
+                      Lid.flatten lid @ Lid.flatten id.txt
+                      |> Lid.unflatten
+                      |> Option.get;
+                    loc;
+                  }
+              | None -> id
+            in
             self#derive_type_ref' self#name ~loc id ts
         | `Ptyp_variant fs -> As_fun (self#derive_of_polyvariant t fs)
 

ppx/test/ptype_open.t

@@ -0,0 +1,102 @@
+We can use the `Ptyp_open` AST node:
+  $ echo '
+  > module X = struct
+  >  type x = (int * int) [@@deriving json]
+  > end
+  > type u = X.(x) [@@deriving json]
+  > let () = print_endline (Ppx_deriving_json_runtime.to_string (u_to_json (1, 2)))
+  > let () = assert (u_of_json (Ppx_deriving_json_runtime.of_string {|[1, 2]|}) = (1, 2))
+  > ' | ./run.sh
+  === ppx output:native ===
+  module X =
+    struct
+      type x = (int * int)[@@deriving json]
+      include
+        struct
+          let _ = fun (_ : x) -> ()
+          [@@@ocaml.warning "-39-11-27"]
+          let rec x_of_json =
+            (fun x ->
+               match x with
+               | `List (x_0::x_1::[]) -> ((int_of_json x_0), (int_of_json x_1))
+               | _ ->
+                   Ppx_deriving_json_runtime.of_json_error ~json:x
+                     "expected a JSON array of length 2" : Yojson.Basic.t -> x)
+          let _ = x_of_json
+          [@@@ocaml.warning "-39-11-27"]
+          let rec x_to_json =
+            (fun x ->
+               match x with
+               | (x_0, x_1) -> `List [int_to_json x_0; int_to_json x_1] : 
+            x -> Yojson.Basic.t)
+          let _ = x_to_json
+        end[@@ocaml.doc "@inline"][@@merlin.hide ]
+    end
+  type u = X.(x)[@@deriving json]
+  include
+    struct
+      let _ = fun (_ : u) -> ()
+      [@@@ocaml.warning "-39-11-27"]
+      let rec u_of_json = (fun x -> X.x_of_json x : Yojson.Basic.t -> u)
+      let _ = u_of_json
+      [@@@ocaml.warning "-39-11-27"]
+      let rec u_to_json = (fun x -> X.x_to_json x : u -> Yojson.Basic.t)
+      let _ = u_to_json
+    end[@@ocaml.doc "@inline"][@@merlin.hide ]
+  let () =
+    print_endline (Ppx_deriving_json_runtime.to_string (u_to_json (1, 2)))
+  let () =
+    assert
+      ((u_of_json (Ppx_deriving_json_runtime.of_string {|[1, 2]|})) = (1, 2))
+  === ppx output:browser ===
+  module X =
+    struct
+      type x = (int * int)[@@deriving json]
+      include
+        struct
+          let _ = fun (_ : x) -> ()
+          [@@@ocaml.warning "-39-11-27"]
+          let rec x_of_json =
+            (fun x ->
+               if
+                 Stdlib.(&&) (Js.Array.isArray x)
+                   (Stdlib.(=)
+                      (Js.Array.length (Obj.magic x : Js.Json.t array)) 2)
+               then
+                 let es = (Obj.magic x : Js.Json.t array) in
+                 ((int_of_json (Js.Array.unsafe_get es 0)),
+                   (int_of_json (Js.Array.unsafe_get es 1)))
+               else
+                 Ppx_deriving_json_runtime.of_json_error ~json:x
+                   "expected a JSON array of length 2" : Js.Json.t -> x)
+          let _ = x_of_json
+          [@@@ocaml.warning "-39-11-27"]
+          let rec x_to_json =
+            (fun x ->
+               match x with
+               | (x_0, x_1) ->
+                   (Obj.magic [|(int_to_json x_0);(int_to_json x_1)|] : 
+                   Js.Json.t) : x -> Js.Json.t)
+          let _ = x_to_json
+        end[@@ocaml.doc "@inline"][@@merlin.hide ]
+    end
+  type u = X.(x)[@@deriving json]
+  include
+    struct
+      let _ = fun (_ : u) -> ()
+      [@@@ocaml.warning "-39-11-27"]
+      let rec u_of_json = (fun x -> X.x_of_json x : Js.Json.t -> u)
+      let _ = u_of_json
+      [@@@ocaml.warning "-39-11-27"]
+      let rec u_to_json = (fun x -> X.x_to_json x : u -> Js.Json.t)
+      let _ = u_to_json
+    end[@@ocaml.doc "@inline"][@@merlin.hide ]
+  let () =
+    print_endline (Ppx_deriving_json_runtime.to_string (u_to_json (1, 2)))
+  let () =
+    assert
+      ((u_of_json (Ppx_deriving_json_runtime.of_string {|[1, 2]|})) = (1, 2))
+  === stdout:native ===
+  [1,2]
+  === stdout:js ===
+  [1,2]