[autocomplete] Correctly render bound type parameters

Summary:
Makes autocomplete take into account all type parameters that were in scope at the requested location.

Assumption this relies on:
Even though we render types of identifiers/members from all across the code, we never grab an identifier from underneath a different type-binding site, so it suffices to render all the types with just the type parameters that were in scope at the requested location. (Panagiotis does this assumption seem reasonable?)

Reviewed By: panagosg7

Differential Revision: D18118627

fbshipit-source-id: e1b9e1a9ab285e1c800584a90148f36fe9f115fa

src/services/autocomplete/autocompleteService_js.ml

@@ -212,7 +212,8 @@ let autocomplete_member
     ac_loc
     ac_trigger
     docblock
-    ~broader_context =
+    ~broader_context
+    ~tparams =
   let ac_loc = loc_of_aloc ~reader ac_loc |> remove_autocomplete_token_from_loc in
   let result = Members.extract ~exclude_proto_members cx this in
   Hh_json.(
@@ -248,18 +249,19 @@ let autocomplete_member
       let genv = Ty_normalizer_env.mk_genv ~full_cx:cx ~file ~typed_ast ~file_sig in
       let rev_result =
         SMap.fold
-          (fun name (_id_loc, t) acc ->
+          (fun name (_id_loc, type_) acc ->
             if (not (autocomplete_is_valid_member name)) || SSet.mem name exclude_keys then
               acc
             else
-              let loc = Type.loc_of_t t |> loc_of_aloc ~reader in
-              ((name, loc), t) :: acc)
+              let loc = Type.loc_of_t type_ |> loc_of_aloc ~reader in
+              let scheme = Type.TypeScheme.{ tparams; type_ } in
+              ((name, loc), scheme) :: acc)
           result_map
           []
       in
       let result =
         rev_result
-        |> Ty_normalizer.from_types ~options:ty_normalizer_options ~genv
+        |> Ty_normalizer.from_schemes ~options:ty_normalizer_options ~genv
         |> Core_list.rev_filter_map ~f:(function
                | ((name, ty_loc), Ok ty) ->
                  Some
@@ -321,6 +323,7 @@ let autocomplete_id
     ~typed_ast
     ~include_super
     ~include_this
+    ~tparams
     ~broader_context =
   let ac_loc = loc_of_aloc ~reader ac_loc |> remove_autocomplete_token_from_loc in
   let scope_info = Scope_builder.program ((new type_killer reader)#program typed_ast) in
@@ -365,26 +368,27 @@ let autocomplete_id
       SMap.empty
   in
   let types = collect_types ~reader (LocSet.of_list (SMap.values names_and_locs)) typed_ast in
-  let normalize_type =
-    Ty_normalizer.from_type
-      ~options:ty_normalizer_options
-      ~genv:(Ty_normalizer_env.mk_genv ~full_cx:cx ~file:(Context.file cx) ~typed_ast ~file_sig)
-  in
   let (results, errors) =
-    SMap.fold
-      (fun name loc (results, errors) ->
-        match normalize_type (LocMap.find loc types) with
-        | Ok ty ->
-          let result =
-            autocomplete_create_result
-              ~show_func_details:(id_type <> JSXIdent)
-              (name, ac_loc)
-              (ty, loc)
-          in
-          (result :: results, errors)
-        | Error error -> (results, error :: errors))
-      names_and_locs
-      ([], [])
+    names_and_locs
+    |> SMap.bindings
+    |> List.map (fun (name, loc) ->
+           ((name, loc), Type.TypeScheme.{ tparams; type_ = LocMap.find loc types }))
+    |> Ty_normalizer.from_schemes
+         ~options:ty_normalizer_options
+         ~genv:(Ty_normalizer_env.mk_genv ~full_cx:cx ~file:(Context.file cx) ~typed_ast ~file_sig)
+    |> List.fold_left
+         (fun (results, errors) ((name, loc), normalization_result) ->
+           match normalization_result with
+           | Ok ty ->
+             let result =
+               autocomplete_create_result
+                 ~show_func_details:(id_type <> JSXIdent)
+                 (name, ac_loc)
+                 (ty, loc)
+             in
+             (result :: results, errors)
+           | Error error -> (results, error :: errors))
+         ([], [])
   in
   let json_data_to_log =
     Hh_json.(
@@ -454,6 +458,7 @@ let autocomplete_jsx
     ac_loc
     ac_trigger
     docblock
+    ~tparams
     ~broader_context =
   Flow_js.(
     let reason = Reason.mk_reason (Reason.RCustom ac_name) ac_loc in
@@ -481,13 +486,14 @@ let autocomplete_jsx
       ac_loc
       ac_trigger
       docblock
+      ~tparams
       ~broader_context)
 
 let autocomplete_get_results
     ~reader cx file_sig typed_ast trigger_character docblock ~broader_context =
   let file_sig = File_sig.abstractify_locs file_sig in
   match Autocomplete_js.process_location ~trigger_character ~typed_ast with
-  | Some (Acid { ac_loc; id_type; include_super; include_this }) ->
+  | Some (tparams, Acid { ac_loc; id_type; include_super; include_this }) ->
     autocomplete_id
       ~reader
       ~cx
@@ -498,8 +504,9 @@ let autocomplete_get_results
       ~typed_ast
       ~include_super
       ~include_this
+      ~tparams
       ~broader_context
-  | Some (Acmem (ac_name, ac_loc, this)) ->
+  | Some (tparams, Acmem (ac_name, ac_loc, this)) ->
     autocomplete_member
       ~reader
       ~exclude_proto_members:false
@@ -512,8 +519,9 @@ let autocomplete_get_results
       ac_loc
       trigger_character
       docblock
+      ~tparams
       ~broader_context
-  | Some (Acjsx (ac_name, used_attr_names, ac_loc, cls)) ->
+  | Some (tparams, Acjsx (ac_name, used_attr_names, ac_loc, cls)) ->
     autocomplete_jsx
       ~reader
       cx
@@ -525,6 +533,7 @@ let autocomplete_get_results
       ac_loc
       trigger_character
       docblock
+      ~tparams
       ~broader_context
   | None ->
     let json_data_to_log =

src/services/autocomplete/autocomplete_js.ml

@@ -37,21 +37,16 @@ let type_of_jsx_name =
     | MemberExpression (_, MemberExpression.{ property = ((_, t), _); _ }) ->
       t)
 
-exception Found of autocomplete_type
+exception Found of Type.typeparam list * autocomplete_type
 
 class searcher (from_trigger_character : bool) =
   object (this)
-    inherit
-      [ALoc.t, ALoc.t * Type.t, ALoc.t, ALoc.t * Type.t] Flow_polymorphic_ast_mapper.mapper as super
-
-    method on_loc_annot x = x
-
-    method on_type_annot x = x
+    inherit Typed_ast_utils.type_parameter_mapper as super
 
     method find x =
       match x with
       | Acid _ when from_trigger_character -> ()
-      | _ -> raise (Found x)
+      | _ -> this#annot_with_tparams (fun tparams -> raise (Found (tparams, x)))
 
     method! t_identifier (((ac_loc, _), { Flow_ast.Identifier.name; _ }) as ident) =
       if is_autocomplete name then
@@ -148,16 +143,18 @@ class searcher (from_trigger_character : bool) =
 
     method! class_body x =
       try super#class_body x
-      with Found (Acid id) ->
-        raise (Found (Acid { id with include_super = true; include_this = true }))
+      with Found (tparams, Acid id) ->
+        raise (Found (tparams, Acid { id with include_super = true; include_this = true }))
 
     method! function_expression x =
       try super#function_expression x
-      with Found (Acid id) -> raise (Found (Acid { id with include_this = true }))
+      with Found (tparams, Acid id) ->
+        raise (Found (tparams, Acid { id with include_this = true }))
 
     method! function_declaration x =
       try super#function_declaration x
-      with Found (Acid id) -> raise (Found (Acid { id with include_this = true }))
+      with Found (tparams, Acid id) ->
+        raise (Found (tparams, Acid { id with include_this = true }))
   end
 
 let autocomplete_id from_trigger_character _cx ac_name _ac_loc =
@@ -174,7 +171,7 @@ let process_location ~trigger_character ~typed_ast =
   try
     ignore ((new searcher (trigger_character <> None))#program typed_ast);
     None
-  with Found res -> Some res
+  with Found (tparams, res) -> Some (tparams, res)
 
 let autocomplete_set_hooks ~trigger_character =
   Type_inference_hooks_js.set_id_hook (autocomplete_id (trigger_character <> None));

src/typing/typed_ast_utils.mli

@@ -5,6 +5,17 @@
  * LICENSE file in the root directory of this source tree.
  *)
 
+class type_parameter_mapper :
+  object
+    inherit [ALoc.t, ALoc.t * Type.t, ALoc.t, ALoc.t * Type.t] Flow_polymorphic_ast_mapper.mapper
+
+    method on_loc_annot : ALoc.t -> ALoc.t
+
+    method on_type_annot : ALoc.t * Type.t -> ALoc.t * Type.t
+
+    method annot_with_tparams : 'a. (Type.typeparam list -> 'a) -> 'a
+  end
+
 val find_exact_match_annotation :
   (ALoc.t, ALoc.t * Type.t) Flow_ast.program -> ALoc.t -> Type.TypeScheme.t option
 (**

tests/autocomplete/autocomplete.exp

@@ -3720,7 +3720,7 @@ normalize-1.js = {
   "result":[
     {
       "name":"b",
-      "type":"mixed",
+      "type":"T",
       "func_details":null,
       "path":"normalize-1.js",
       "line":3,
@@ -3814,7 +3814,7 @@ normalize-2.js = {
     },
     {
       "name":"c",
-      "type":"mixed",
+      "type":"T",
       "func_details":null,
       "path":"normalize-2.js",
       "line":4,