refactor: remove Document.is_merlin (#888)

Signed-off-by: Rudi Grinberg <me@rgrinberg.com>

ps-id: 9f82a75d-df56-4ab8-ba05-1bbe71e783f6

ocaml-lsp-server/src/document.ml

@@ -106,10 +106,6 @@ let tdoc = function
 
 let uri t = Text_document.documentUri (tdoc t)
 
-let is_merlin = function
-  | Other _ -> false
-  | Merlin _ -> true
-
 let kind = function
   | Merlin _ as t -> `Merlin (Kind.of_fname (Uri.to_path (uri t)))
   | Other _ -> `Other

ocaml-lsp-server/src/document.mli

@@ -22,8 +22,6 @@ module Kind : sig
     | Impl
 end
 
-val is_merlin : t -> bool
-
 val kind : t -> [ `Merlin of Kind.t | `Other ]
 
 val syntax : t -> Syntax.t

ocaml-lsp-server/src/dune.ml

@@ -257,9 +257,9 @@ end = struct
                   | Failed | Interrupted | Success ->
                     let* () =
                       Document_store.change_all document_store ~f:(fun doc ->
-                          match Document.is_merlin doc with
-                          | false -> Fiber.return doc
-                          | true ->
+                          match Document.kind doc with
+                          | `Other -> Fiber.return doc
+                          | `Merlin _ ->
                             let doc = Document.update_text doc [] in
                             let+ () =
                               Diagnostics.merlin_diagnostics diagnostics doc

ocaml-lsp-server/src/ocaml_lsp_server.ml

@@ -269,7 +269,8 @@ module Formatter = struct
 
   let run rpc doc =
     let state : State.t = Server.state rpc in
-    if Document.is_merlin doc then
+    match Document.kind doc with
+    | `Merlin _ -> (
       let* res =
         let* res = Ocamlformat_rpc.format_doc state.ocamlformat_rpc doc in
         match res with
@@ -289,8 +290,8 @@ module Formatter = struct
           task_if_running state.detached ~f:(fun () ->
               Server.notification rpc (ShowMessage msg))
         in
-        Jsonrpc.Response.Error.raise error
-    else
+        Jsonrpc.Response.Error.raise error)
+    | `Other -> (
       match Dune.for_doc (State.dune state) doc with
       | [] ->
         let message =
@@ -314,7 +315,7 @@ module Formatter = struct
             State.log_msg rpc ~type_:MessageType.Warning ~message
         in
         let+ to_ = Dune.Instance.format_dune_file dune doc in
-        Some (Diff.edit ~from:(Document.text doc) ~to_)
+        Some (Diff.edit ~from:(Document.text doc) ~to_))
 end
 
 let location_of_merlin_loc uri : _ -> (_, string) result = function
@@ -370,13 +371,14 @@ let signature_help (state : State.t)
   in
   (* TODO use merlin resources efficiently and do everything in 1 thread *)
   let* application_signature =
-    if Document.is_merlin doc then
+    match Document.kind doc with
+    | `Other -> Fiber.return None
+    | `Merlin _ ->
       Document.with_pipeline_exn doc (fun pipeline ->
           let typer = Mpipeline.typer_result pipeline in
           let pos = Mpipeline.get_lexing_pos pipeline pos in
           let node = Mtyper.node_at typer pos in
           Signature_help.application_signature node ~prefix)
-    else Fiber.return None
   in
   match application_signature with
   | None ->