Resolve applied fields and constructors to the functor's declarations

Codex review on #9084: an applied functor's record fields and
constructors are read from its signature, where they have no location.
Go to Definition returned that missing location, and rename added it as a
reference, producing edits at character -1. Their lookups now go through
the type they were renamed from, which has the body's locations, and
fields and constructors without a location are not registered as
references.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Kbf3gLMawVgtmiKy3TMBc3
Claude-Session: https://claude.ai/code/session_01Kr4cjoUi2f5VpMvE6wT9bo
Signed-off-by: Christoph Knittel <ck@cca.io>

Author: cknitt

analysis/src/process_extra.ml

@@ -29,14 +29,19 @@ let extra_for_file ~(file : File.t) =
         (TypeDefinition (d.name.txt, d.item.Type.decl, stamp));
       add_reference ~extra stamp d.name.loc;
       match d.item.Type.kind with
+      (* Fields and constructors of a type read from a signature, such as
+         an applied functor's, have no location of their own; references
+         to them are those of the declarations they come from. *)
       | Record labels ->
         labels
+        |> List.filter (fun {fname} -> not fname.loc.loc_ghost)
         |> List.iter (fun {stamp; fname; typ} ->
             add_reference ~extra stamp fname.loc;
             add_loc_item extra fname.loc
               (Typed (d.name.txt, typ, Definition (d.stamp, Field fname.txt))))
       | Variant constructors ->
         constructors
+        |> List.filter (fun {Constructor.cname} -> not cname.loc.loc_ghost)
         |> List.iter (fun {Constructor.stamp; cname} ->
             add_reference ~extra stamp cname.loc;
             let t =

analysis/src/references.ml

@@ -124,16 +124,23 @@ let declared_for_tip ~(stamps : Stamps.t) stamp (tip : Tip.t) =
     Stamps.find_module stamps stamp
     |> Option.map (fun x -> {x with Declared.item = ()})
 
+(* The type a renamed type of an applied functor comes from, whose fields
+   and constructors have source locations. *)
+let original_type_stamp (file : File.t) stamp =
+  match Hashtbl.find_opt file.renamed_stamps stamp with
+  | Some original -> original
+  | None -> stamp
+
 let get_field (file : File.t) stamp name =
-  match Stamps.find_type file.stamps stamp with
+  match Stamps.find_type file.stamps (original_type_stamp file stamp) with
   | None -> None
   | Some {item = {kind}} -> (
     match kind with
     | Record fields -> fields |> List.find_opt (fun f -> f.fname.txt = name)
     | _ -> None)
 
 let get_constructor (file : File.t) stamp name =
-  match Stamps.find_type file.stamps stamp with
+  match Stamps.find_type file.stamps (original_type_stamp file stamp) with
   | None -> None
   | Some {item = {kind}} -> (
     match kind with

tests/analysis_tests/tests/src/AppliedFunctor.res

@@ -45,3 +45,20 @@ module N = WithNested(IntOrd)
 
 let n = N.Nested.value
 //        ^ref
+
+module WithShapes = (O: Ord) => {
+  type point = {x: int}
+  type shape = Dot | Box(int)
+}
+
+module Shapes = WithShapes(IntOrd)
+
+let p: Shapes.point = {x: 1}
+let px = p.x
+//         ^def
+
+let shape = Shapes.Box(1)
+//                 ^def
+
+let py = p.x
+//         ^ren y

tests/analysis_tests/tests/src/expected/AppliedFunctor.res.txt

@@ -168,3 +168,58 @@ References src/AppliedFunctor.res 45:10
   }
 ]
 
+Definition src/AppliedFunctor.res 56:11
+{
+  "range": {
+    "end": { "character": 17, "line": 49 },
+    "start": { "character": 16, "line": 49 }
+  },
+  "uri": "file:///AppliedFunctor.res"
+}
+
+Definition src/AppliedFunctor.res 59:19
+{
+  "range": {
+    "end": { "character": 24, "line": 50 },
+    "start": { "character": 21, "line": 50 }
+  },
+  "uri": "file:///AppliedFunctor.res"
+}
+
+Rename src/AppliedFunctor.res 62:11 y
+[
+  {
+    "edits": [
+      {
+        "newText": "y",
+        "range": {
+          "end": { "character": 17, "line": 49 },
+          "start": { "character": 16, "line": 49 }
+        }
+      },
+      {
+        "newText": "y",
+        "range": {
+          "end": { "character": 24, "line": 55 },
+          "start": { "character": 23, "line": 55 }
+        }
+      },
+      {
+        "newText": "y",
+        "range": {
+          "end": { "character": 12, "line": 56 },
+          "start": { "character": 11, "line": 56 }
+        }
+      },
+      {
+        "newText": "y",
+        "range": {
+          "end": { "character": 12, "line": 62 },
+          "start": { "character": 11, "line": 62 }
+        }
+      }
+    ],
+    "textDocument": { "uri": "file:///AppliedFunctor.res", "version": 0 }
+  }
+]
+