Rewrite nested JSX component paths to direct hoisted exports

compiler/core/js_of_lam_block.ml

@@ -43,7 +43,7 @@ let field (field_info : Lam_compat.field_dbg_info) e (i : int32) =
   | Fld_cons -> E.cons_access e i
   | Fld_record_inline {name} -> E.inline_record_access e name i
   | Fld_record {name} -> E.record_access e name i
-  | Fld_module {name} -> E.module_access e name i
+  | Fld_module {name; jsx_component = _} -> E.module_access e name i
 
 let field_by_exp e i = E.array_index e i
 

compiler/core/js_pass_nested_component_exports.ml

@@ -0,0 +1,212 @@
+(* Copyright (C) 2026 - Authors of ReScript
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * In addition to the permissions granted to you by the LGPL, you may combine
+ * or link a "work that uses the Library" with a publicly distributed version
+ * of this file to produce a combined library or application, then distribute
+ * that combined work under the terms of your choosing, with no requirement
+ * to comply with the obligations normally placed on you by section 4 of the
+ * LGPL version 3 (or the corresponding section of a later version of the LGPL
+ * should you choose to use a later version).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)
+
+module E = Js_exp_make
+
+module StringSet = Set.Make (String)
+
+type candidate = {
+  module_ident: Ident.t;
+  hidden_export_name: string;
+}
+
+let dynamic_import_module_root (expr : J.expression) =
+  match expr.expression_desc with
+  | Await
+      {
+        expression_desc =
+          Call
+            ({expression_desc = Var (Id import_ident); _}, [arg], _);
+        _;
+      }
+    when String.equal import_ident.name "import" -> (
+      match arg.expression_desc with
+      | Str {txt; _} ->
+        let basename = Filename.basename txt in
+        let suffixes = [".res.mjs"; ".res.js"; ".mjs"; ".js"] in
+        let rec strip_suffix = function
+          | [] -> basename
+          | suffix :: rest ->
+            if Filename.check_suffix basename suffix then
+              Filename.chop_suffix basename suffix
+            else strip_suffix rest
+        in
+        Some (strip_suffix suffixes)
+      | _ -> None)
+  | _ -> None
+
+let marker_name hidden_export_name = hidden_export_name ^ "$jsx"
+
+let hidden_component_suffix (module_ident : Ident.t) =
+  "$" ^ Ident.name module_ident
+
+let is_hidden_component_name_for module_ident ident =
+  Ext_string.ends_with (Ident.name ident) (hidden_component_suffix module_ident)
+
+let find_hidden_alias_by_value block module_ident value_ident =
+  List.find_map (fun (st : J.statement) ->
+      match st.statement_desc with
+      | Variable
+          {
+            ident;
+            value = Some {expression_desc = Var (Id target); _};
+            property = _;
+            ident_info = _;
+          }
+        when Ident.same target value_ident
+             && is_hidden_component_name_for module_ident ident ->
+        Some ident
+      | _ -> None)
+    block
+
+let has_export_name exports name =
+  List.exists (fun (ident : Ident.t) -> String.equal (Ident.name ident) name) exports
+
+let candidate_of_statement block exports (st : J.statement) =
+  match st.statement_desc with
+  | Variable
+      {
+        ident = module_ident;
+        value =
+          Some
+            {
+              expression_desc =
+                Caml_block
+                  ([{expression_desc = Var (Id value_ident); _}], Immutable, _, Blk_module ["make"]);
+              _;
+            };
+        property = _;
+        ident_info = _;
+      } -> (
+      let hidden_ident =
+        if is_hidden_component_name_for module_ident value_ident then
+          Some value_ident
+        else find_hidden_alias_by_value block module_ident value_ident
+      in
+      match hidden_ident with
+      | Some hidden_ident
+        when has_export_name exports hidden_ident.name ->
+        Some
+          {
+            module_ident;
+            hidden_export_name = hidden_ident.name;
+          }
+      | Some _ | None -> None)
+  | _ -> None
+
+let collect_candidates block exports =
+  Ext_list.filter_map block (candidate_of_statement block exports)
+
+let hidden_export_names_to_remove candidates =
+  Ext_list.fold_left candidates StringSet.empty (fun acc candidate ->
+      acc |> StringSet.add (Ident.name candidate.module_ident)
+      |> StringSet.add (marker_name candidate.hidden_export_name))
+
+let marker_names_to_remove_from_block candidates =
+  Ext_list.fold_left candidates StringSet.empty (fun acc candidate ->
+      StringSet.add (marker_name candidate.hidden_export_name) acc)
+
+let candidate_by_module_ident candidates module_ident =
+  List.find_map (fun candidate ->
+      if Ident.same candidate.module_ident module_ident then Some candidate
+      else None)
+    candidates
+
+let rewrite_block block candidates removed_marker_names =
+  List.concat_map (fun (st : J.statement) ->
+      match st.statement_desc with
+      | Variable {ident; value; property; ident_info} -> (
+        match candidate_by_module_ident candidates ident with
+        | Some _ -> [st]
+        | None ->
+          if StringSet.mem (Ident.name ident) removed_marker_names then []
+          else [st])
+      | _ -> [st])
+    block
+
+let dynamic_import_aliases block =
+  List.fold_left
+    (fun aliases (st : J.statement) ->
+      match st.statement_desc with
+      | Variable {ident; value = Some expr; _} -> (
+        match dynamic_import_module_root expr with
+        | Some module_root -> Map_ident.add aliases ident module_root
+        | None -> aliases)
+      | _ -> aliases)
+    Map_ident.empty block
+
+let rewrite_dynamic_import_component_access aliases (expr : J.expression) =
+  let rec collect_segments segments (expr : J.expression) =
+    match expr.expression_desc with
+    | Static_index (inner, field, _) -> collect_segments (field :: segments) inner
+    | Var (Id id) -> (
+      match Map_ident.find_opt aliases id with
+      | Some module_root when segments <> [] -> Some (id, module_root, segments)
+      | Some _ | None -> None)
+    | _ -> None
+  in
+  match expr.expression_desc with
+  | Static_index (inner, "make", _) -> (
+    match collect_segments [] inner with
+    | Some (id, module_root, segments) ->
+      let segments = List.rev segments in
+      let hidden_name =
+        match segments with
+        | first :: _ when Ext_string.starts_with first (module_root ^ "$") ->
+          String.concat "$" segments
+        | _ -> String.concat "$" (module_root :: segments)
+      in
+      {expr with expression_desc = Static_index (E.var id, hidden_name, None)}
+    | None -> expr)
+  | _ -> expr
+
+let rewrite_dynamic_import_block block =
+  let aliases = dynamic_import_aliases block in
+  if Map_ident.is_empty aliases then block
+  else
+    let mapper =
+      {
+        Js_record_map.super with
+        expression =
+          (fun self expr ->
+            let expr = Js_record_map.super.expression self expr in
+            rewrite_dynamic_import_component_access aliases expr);
+      }
+    in
+    mapper.block mapper block
+
+let program (js : J.program) : J.program =
+  let candidates = collect_candidates js.block js.exports in
+  let removed_export_names = hidden_export_names_to_remove candidates in
+  let removed_marker_names = marker_names_to_remove_from_block candidates in
+  let exports =
+    Ext_list.filter js.exports (fun (ident : Ident.t) ->
+        not (StringSet.mem (Ident.name ident) removed_export_names))
+  in
+  let export_set = Set_ident.of_list exports in
+  let block =
+    rewrite_dynamic_import_block
+      (rewrite_block js.block candidates removed_marker_names)
+  in
+  {J.block; exports; export_set}

compiler/core/js_pass_nested_component_exports.mli

@@ -0,0 +1,28 @@
+(* Copyright (C) 2026 - Authors of ReScript
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * In addition to the permissions granted to you by the LGPL, you may combine
+ * or link a "work that uses the Library" with a publicly distributed version
+ * of this file to produce a combined library or application, then distribute
+ * that combined work under the terms of your choosing, with no requirement
+ * to comply with the obligations normally placed on you by section 4 of the
+ * LGPL version 3 (or the corresponding section of a later version of the LGPL
+ * should you choose to use a later version).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)
+
+(* Rewrite nested React component module exports from `{make: fn}` wrappers to
+   direct component exports, while keeping `.make` as a self-reference for
+   compatibility with existing generated call sites. *)
+val program : J.program -> J.program

compiler/core/lam.ml

@@ -555,7 +555,8 @@ let prim ~primitive:(prim : Lam_primitive.t) ~args loc : t =
         | ( f :: fields,
             Lprim
               {
-                primitive = Pfield (pos, Fld_module {name = f1});
+                primitive =
+                  Pfield (pos, Fld_module {name = f1; jsx_component = false});
                 args = [(Lglobal_module (v1, _) | Lvar v1)];
               }
             :: args ) ->
@@ -566,7 +567,8 @@ let prim ~primitive:(prim : Lam_primitive.t) ~args loc : t =
       | ( field1 :: rest,
           Lprim
             {
-              primitive = Pfield (pos, Fld_module {name = f1});
+              primitive =
+                Pfield (pos, Fld_module {name = f1; jsx_component = false});
               args = [((Lglobal_module (v1, _) | Lvar v1) as lam)];
             }
           :: args1 ) ->

compiler/core/lam_analysis.ml

@@ -123,7 +123,12 @@ let rec no_side_effects (lam : Lam.t) : bool =
   (* | Lsend _ -> false  *)
   | Lapply
       {
-        ap_func = Lprim {primitive = Pfield (_, Fld_module {name = "from_fun"})};
+        ap_func =
+          Lprim
+            {
+              primitive =
+                Pfield (_, Fld_module {name = "from_fun"; jsx_component = _});
+            };
         ap_args = [arg];
       } ->
     no_side_effects arg

compiler/core/lam_arity_analysis.ml

@@ -42,7 +42,7 @@ let rec get_arity (meta : Lam_stats.t) (lam : Lam.t) : Lam_arity.t =
   | Llet (_, _, _, l) -> get_arity meta l
   | Lprim
       {
-        primitive = Pfield (_, Fld_module {name});
+        primitive = Pfield (_, Fld_module {name; jsx_component = _});
         args = [Lglobal_module (id, dynamic_import)];
         _;
       } -> (
@@ -58,7 +58,7 @@ let rec get_arity (meta : Lam_stats.t) (lam : Lam.t) : Lam_arity.t =
           [
             Lprim
               {
-                primitive = Pfield (_, Fld_module {name});
+                primitive = Pfield (_, Fld_module {name; jsx_component = _});
                 args = [Lglobal_module (id, dynamic_import)];
               };
           ];

compiler/core/lam_compat.ml

@@ -64,7 +64,7 @@ type let_kind = Lambda.let_kind = Strict | Alias | StrictOpt | Variable
 
 type field_dbg_info = Lambda.field_dbg_info =
   | Fld_record of {name: string; mutable_flag: Asttypes.mutable_flag}
-  | Fld_module of {name: string}
+  | Fld_module of {name: string; jsx_component: bool}
   | Fld_record_inline of {name: string}
   | Fld_record_extension of {name: string}
   | Fld_tuple

compiler/core/lam_compat.mli

@@ -28,7 +28,7 @@ type let_kind = Lambda.let_kind = Strict | Alias | StrictOpt | Variable
 
 type field_dbg_info = Lambda.field_dbg_info =
   | Fld_record of {name: string; mutable_flag: Asttypes.mutable_flag}
-  | Fld_module of {name: string}
+  | Fld_module of {name: string; jsx_component: bool}
   | Fld_record_inline of {name: string}
   | Fld_record_extension of {name: string}
   | Fld_tuple