Revert: remove raparsing of longident to index modules in paths

This reparsing has very bad performances. The correct way to deal with
issue is to have the compiler store precise locations in longidents.

src/analysis/occurrences.ml

@@ -25,7 +25,7 @@ let decl_of_path_or_lid env namespace path lid =
     end
   | _ -> Env_lookup.by_path path namespace env
 
-let index_buffer_ ~config ~source ~current_buffer_path ~local_defs () =
+let index_buffer_ ~current_buffer_path ~local_defs () =
   let {Logger. log} = Logger.for_section "index" in
   let defs = Hashtbl.create 64 in
   let module Shape_reduce =
@@ -80,46 +80,14 @@ let index_buffer_ ~config ~source ~current_buffer_path ~local_defs () =
           index_decl ()
         end
   in
-  let f ~namespace env path (lid : Longident.t Location.loc)  =
-    (* The compiler lacks sufficient location information to precisely hihglight
-       modules in paths. This function hacks around that issue when looking for
-       occurrences in the current buffer only. *)
-    (* We rely on a custom re-parsing of the longidents that provide us with
-       location information and match these with the real path and longident. *)
-    let rec iter_on_path ~namespace (path : Path.t) lid reparsed =
-      log ~title:"iter_on_path" "Path %a, lid: %a"
-        Logger.fmt (Fun.flip Path.print path)
-        Logger.fmt (Fun.flip Pprintast.longident lid.Location.txt);
-      match path, lid.txt, reparsed with
-      | Pdot (path', n), (Ldot (_, s) | Lident s), _
-          when n <> s && String.lowercase_ascii n = n ->
-          iter_on_path ~namespace path' lid reparsed
-      | (Pdot _ | Pident _), Lident s, [{ Location.txt = name; loc}]
-        when name = s ->
-          log ~title:"iter_on_path" "Last %a, lid: %a"
-            Logger.fmt (Fun.flip Path.print path)
-            Logger.fmt (Fun.flip Pprintast.longident lid.Location.txt);
-          f ~namespace env path { lid with loc = loc }
-      | Pdot (path', _), Ldot (lid', s), { txt = name; loc} :: tl when name = s ->
-          let () = f ~namespace env path { lid with loc = loc } in
-          iter_on_path ~namespace:Module path' { lid with txt = lid' } tl
-      | Papply _, _, _ -> f ~namespace env path lid
-      | _, _, _ -> f ~namespace env path lid
-    in
-    let reparsed_lid =
-      Misc_utils.parse_identifier (config, source) lid.loc.loc_end
-      |> List.rev
-    in
-    iter_on_path ~namespace path lid reparsed_lid
-  in
   Ast_iterators.iter_on_usages ~f local_defs;
   defs
 
 let index_buffer =
   (* Right now, we only cache the last used index. We could do better by caching
      the index for every known buffer. *)
   let cache = ref None in
-  fun ~config ~source ~current_buffer_path ~stamp ~local_defs () ->
+  fun ~current_buffer_path ~stamp ~local_defs () ->
     let {Logger. log} = Logger.for_section "index" in
     match !cache with
     | Some (path, stamp', value) when
@@ -131,7 +99,7 @@ let index_buffer =
     | _ ->
       log ~title:"index_cache" "No valid cache found, reindexing.";
       let result =
-        index_buffer_ ~config ~source ~current_buffer_path ~local_defs ()
+        index_buffer_ ~current_buffer_path ~local_defs ()
       in
       cache := Some (current_buffer_path, stamp, result);
       result
@@ -189,7 +157,7 @@ let comp_unit_of_uid = function
   | Item { comp_unit; _ } -> Some comp_unit
   | Internal | Predef _ -> None
 
-let locs_of ~config ~source ~env ~typer_result ~pos path =
+let locs_of ~config ~env ~typer_result ~pos path =
   log ~title:"occurrences" "Looking for occurences of %s (pos: %s)"
     path
     (Lexing.print_position () pos);
@@ -233,7 +201,7 @@ let locs_of ~config ~source ~env ~typer_result ~pos path =
     log ~title:"locs_of" "Indexing current buffer";
     let buffer_index =
       let stamp = Mtyper.get_stamp typer_result in
-      index_buffer ~config ~source ~current_buffer_path ~stamp ~local_defs ()
+      index_buffer ~current_buffer_path ~stamp ~local_defs ()
     in
     let buffer_locs = Hashtbl.find_opt buffer_index def_uid in
     let locs = Option.value ~default:LidSet.empty buffer_locs in

src/analysis/occurrences.mli

@@ -1,6 +1,5 @@
 val locs_of
   : config:Mconfig.t
-  -> source:Msource.t
   -> env:Env.t
   -> typer_result:Mtyper.result
   -> pos:Lexing.position

src/frontend/query_commands.ml

@@ -797,7 +797,6 @@ let dispatch pipeline (type a) : a Query_protocol.t -> a =
 
   | Occurrences (`Ident_at pos, _) ->
     let config = Mpipeline.final_config pipeline in
-    let source = Mpipeline.raw_source pipeline in
     let typer_result = Mpipeline.typer_result pipeline in
     let pos = Mpipeline.get_lexing_pos pipeline pos in
     let env, _node = Mbrowse.leaf_node (Mtyper.node_at typer_result pos) in
@@ -810,7 +809,7 @@ let dispatch pipeline (type a) : a Query_protocol.t -> a =
       path
     in
     let locs =
-      Occurrences.locs_of ~config ~source ~env ~typer_result ~pos path
+      Occurrences.locs_of ~config ~env ~typer_result ~pos path
       |> Result.value ~default:[]
     in
     let loc_start l = l.Location.loc_start in

tests/test-dirs/occurrences/mod-in-path-2.t

@@ -7,6 +7,7 @@
   >   | Mod.A -> ()
   > EOF
 
+FIXME: we could expect module appearing in paths to be highlighted
   $ $MERLIN single occurrences -identifier-at 1:8 -filename test.ml <test.ml | 
   > jq '.value'
   [
@@ -19,26 +20,6 @@
         "line": 1,
         "col": 10
       }
-    },
-    {
-      "start": {
-        "line": 5,
-        "col": 8
-      },
-      "end": {
-        "line": 5,
-        "col": 11
-      }
-    },
-    {
-      "start": {
-        "line": 6,
-        "col": 4
-      },
-      "end": {
-        "line": 6,
-        "col": 7
-      }
     }
   ]
 

tests/test-dirs/occurrences/mod-in-path-3.t

@@ -8,6 +8,7 @@
   >   | Mod.A r -> r.lbl
   > EOF
 
+FIXME: we could expect module appearing in paths to be highlighted
   $ $MERLIN single occurrences -identifier-at 4:9 -filename test.ml <test.ml | 
   > jq '.value'
   [
@@ -20,26 +21,6 @@
         "line": 1,
         "col": 10
       }
-    },
-    {
-      "start": {
-        "line": 4,
-        "col": 8
-      },
-      "end": {
-        "line": 4,
-        "col": 11
-      }
-    },
-    {
-      "start": {
-        "line": 7,
-        "col": 4
-      },
-      "end": {
-        "line": 7,
-        "col": 7
-      }
     }
   ]
 

tests/test-dirs/occurrences/mod-in-path.t

@@ -13,6 +13,7 @@
   > let _ = let open Mod in Nod.x
   > EOF
 
+FIXME: we could expect module appearing in paths to be highlighted
   $ $MERLIN single occurrences -identifier-at 6:13 -filename test.ml <test.ml | 
   > jq '.value'
   [
@@ -25,50 +26,10 @@
         "line": 2,
         "col": 12
       }
-    },
-    {
-      "start": {
-        "line": 6,
-        "col": 12
-      },
-      "end": {
-        "line": 6,
-        "col": 15
-      }
-    },
-    {
-      "start": {
-        "line": 7,
-        "col": 14
-      },
-      "end": {
-        "line": 7,
-        "col": 17
-      }
-    },
-    {
-      "start": {
-        "line": 9,
-        "col": 0
-      },
-      "end": {
-        "line": 9,
-        "col": 3
-      }
-    },
-    {
-      "start": {
-        "line": 12,
-        "col": 24
-      },
-      "end": {
-        "line": 12,
-        "col": 27
-      }
     }
   ]
 
-
+FIXME: we could expect module appearing in paths to be highlighted
   $ $MERLIN single occurrences -identifier-at 12:18 -filename test.ml <test.ml | 
   > jq '.value'
   [
@@ -82,36 +43,6 @@
         "col": 10
       }
     },
-    {
-      "start": {
-        "line": 6,
-        "col": 8
-      },
-      "end": {
-        "line": 6,
-        "col": 11
-      }
-    },
-    {
-      "start": {
-        "line": 7,
-        "col": 8
-      },
-      "end": {
-        "line": 7,
-        "col": 11
-      }
-    },
-    {
-      "start": {
-        "line": 8,
-        "col": 8
-      },
-      "end": {
-        "line": 8,
-        "col": 11
-      }
-    },
     {
       "start": {
         "line": 12,