Refer uses of a functor applied from another file to that file's members

A use of a member of a functor applied from another file referred to the
caller's copy, so references and renames no longer crossed files as they
did when the application resolved to the functor. Such a use refers to the
functor's member again, for values, types, fields, constructors and
modules, and a signature's nested modules now name their items' paths.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Kbf3gGkPma9LAZimuQjnrP
Claude-Session: https://claude.ai/code/session_01Kr4cjoUi2f5VpMvE6wT9bo
Signed-off-by: Christoph Knittel <ck@cca.io>

Author: cknitt

analysis/src/process_cmt.ml

@@ -148,7 +148,7 @@ let rec for_type_signature_item ~(env : Shared_types.Env.t)
     let name = Ident.name ident in
     let declared =
       add_declared ~extent:md_loc
-        ~item:(for_type_module ~name ~env md_type)
+        ~item:(for_type_module ~name ~env:(env |> Env.add_module ~name) md_type)
         ~name:(Location.mkloc name md_loc)
         ~stamp:(Ident.binding_time ident) ~env md_attributes
         (Exported.add exported Exported.Module)

analysis/src/process_extra.ml

@@ -152,22 +152,55 @@ let extra_for_cmt ~(iterator : Tast_iterator.iterator)
     extra_for_signature_items ~iterator items;
     extra_for_parts parts
 
-(* A use of an applied functor's member is also a use of the declaration
-   in the functor's body that it was renamed from. *)
-let add_reference_with_original ~(env : Query_env.t) ~extra stamp loc =
-  add_reference ~extra stamp loc;
-  match Hashtbl.find_opt env.file.renamed_stamps stamp with
-  | Some original -> add_reference ~extra original loc
-  | None -> ()
+(* The module and path of a member of a functor applied from another file:
+   the functor's path followed by the member's path inside its result. *)
+let applied_global ~(env : Query_env.t) stamp (tip : Tip.t) =
+  let declared =
+    let of_declared (d : _ Declared.t) = (d.module_path, d.name.txt) in
+    match tip with
+    | Value -> Stamps.find_value env.file.stamps stamp |> Option.map of_declared
+    | Type | Field _ | Constructor _ ->
+      Stamps.find_type env.file.stamps stamp |> Option.map of_declared
+    | Module ->
+      Stamps.find_module env.file.stamps stamp |> Option.map of_declared
+  in
+  let rec loop (module_path : Module_path.t) inner =
+    match module_path with
+    | IncludedModule (functor_path, _) -> (
+      match Resolve_path.from_compiler_path ~env functor_path with
+      | Global (module_name, path) -> Some (module_name, path @ inner)
+      | Stamp _ | Exported _ | GlobalMod _ | NotFound -> None)
+    | ExportedModule {name; module_path} -> loop module_path (name :: inner)
+    | File _ | NotVisible -> None
+  in
+  match declared with
+  | Some (module_path, name) when stamp >= Process_cmt.renamed_stamp_floor ->
+    loop module_path [name]
+  | _ -> None
+
+(* A use of a local declaration. A use of an applied functor's member is
+   also a use of the declaration in the functor's body that it was renamed
+   from, and when the functor is in another file, it is a use of that file's
+   declaration, as uses of the functor's own members are, for references
+   across files to find it. *)
+let reference_to_stamp ~(env : Query_env.t) ~extra stamp tip loc =
+  match applied_global ~env stamp tip with
+  | Some (module_name, path) ->
+    add_external_reference ~extra module_name path tip loc;
+    GlobalReference (module_name, path, tip)
+  | None ->
+    add_reference ~extra stamp loc;
+    (match Hashtbl.find_opt env.file.renamed_stamps stamp with
+    | Some original -> add_reference ~extra original loc
+    | None -> ());
+    LocalReference (stamp, tip)
 
 let add_for_path ~env ~extra path lident loc typ tip =
   let ident_name = Longident.last lident in
   let ident_loc = Utils.end_of_location loc (String.length ident_name) in
   let loc_type =
     match Resolve_path.from_compiler_path ~env path with
-    | Stamp stamp ->
-      add_reference_with_original ~env ~extra stamp ident_loc;
-      LocalReference (stamp, tip)
+    | Stamp stamp -> reference_to_stamp ~env ~extra stamp tip ident_loc
     | NotFound -> NotFound
     | Global (module_name, path) ->
       add_external_reference ~extra module_name path tip ident_loc;
@@ -178,9 +211,7 @@ let add_for_path ~env ~extra path lident loc typ tip =
         | Type -> Exported.find env.exported Exported.Type name
         | _ -> Exported.find env.exported Exported.Value name
       with
-      | Some stamp ->
-        add_reference_with_original ~env ~extra stamp ident_loc;
-        LocalReference (stamp, tip)
+      | Some stamp -> reference_to_stamp ~env ~extra stamp tip ident_loc
       | None -> NotFound)
     | GlobalMod _ -> NotFound
   in
@@ -192,22 +223,28 @@ let add_for_path_parent ~env ~extra path loc =
     | GlobalMod module_name ->
       add_file_reference ~extra module_name loc;
       TopLevelModule module_name
-    | Stamp stamp ->
-      add_reference_with_original ~env ~extra stamp loc;
-      LModule (LocalReference (stamp, Module))
+    | Stamp stamp -> LModule (reference_to_stamp ~env ~extra stamp Module loc)
     | NotFound -> LModule NotFound
     | Global (module_name, path) ->
       add_external_reference ~extra module_name path Module loc;
       LModule (GlobalReference (module_name, path, Module))
     | Exported (env, name) -> (
       match Exported.find env.exported Exported.Module name with
-      | Some stamp ->
-        add_reference_with_original ~env ~extra stamp loc;
-        LModule (LocalReference (stamp, Module))
+      | Some stamp -> LModule (reference_to_stamp ~env ~extra stamp Module loc)
       | None -> LModule NotFound)
   in
   add_loc_item extra loc loc_type
 
+(* A type of a functor applied from another file is that file's type, as
+   for its other members. *)
+let get_type_at_stamp ~env stamp =
+  match applied_global ~env stamp Type with
+  | Some (module_name, path) -> `Global (module_name, path)
+  | None -> (
+    match Stamps.find_type env.file.stamps stamp with
+    | Some declared_type -> `Local declared_type
+    | None -> `Not_found)
+
 let get_type_at_path ~env path =
   match Resolve_path.from_compiler_path ~env path with
   | GlobalMod _ -> `Not_found
@@ -216,16 +253,8 @@ let get_type_at_path ~env path =
   | Exported (env, name) -> (
     match Exported.find env.exported Exported.Type name with
     | None -> `Not_found
-    | Some stamp -> (
-      let declared_type = Stamps.find_type env.file.stamps stamp in
-      match declared_type with
-      | Some declared_type -> `Local declared_type
-      | None -> `Not_found))
-  | Stamp stamp -> (
-    let declared_type = Stamps.find_type env.file.stamps stamp in
-    match declared_type with
-    | Some declared_type -> `Local declared_type
-    | None -> `Not_found)
+    | Some stamp -> get_type_at_stamp ~env stamp)
+  | Stamp stamp -> get_type_at_stamp ~env stamp
 
 let add_for_field ~env ~extra ~record_type ~field_type {Asttypes.txt; loc} =
   match (Shared.dig record_type).desc with

tests/analysis_tests/tests/src/AppliedFunctor.res

@@ -33,6 +33,7 @@ module WithNested = (O: Ord) => {
   module Nested = {
     //     ^ref
     let value = 1
+    //  ^ren nestedValue
   }
 }
 
@@ -48,6 +49,7 @@ let n = N.Nested.value
 
 module WithShapes = (O: Ord) => {
   type point = {x: int}
+  //   ^ref
   type shape = Dot | Box(int)
 }
 

tests/analysis_tests/tests/src/AppliedFunctorUse.res

@@ -59,3 +59,18 @@ let nv4 = N.Nested.value
 
 let p2: Shapes.point = {x: 2}
 //             ^ref
+
+let s3 = StrSet.add([], "c")
+//              ^ren addItem
+
+let p3: Shapes.point = {x: 3}
+//             ^ren location
+
+let nv5 = N.Nested.value
+//                 ^ren renamedValue
+
+let px2 = p.x
+//          ^ref
+
+let box2 = Shapes.Box(2)
+//                ^ren Square