hmm avoid passing flag to dune

lsp/src/cli.ml

@@ -12,6 +12,7 @@ module Arg = struct
     ; mutable stdio : bool
     ; mutable spec : (string * Arg.spec * string) list
     ; mutable clientProcessId : int option
+    ; mutable dune_diagnostics : bool
     }
 
   let port t ~name ~description =
@@ -30,6 +31,7 @@ module Arg = struct
       ; stdio = false
       ; spec = []
       ; clientProcessId = None
+      ; dune_diagnostics = true
       }
     in
     let spec =
@@ -43,6 +45,9 @@ module Arg = struct
       ; ( "--clientProcessId"
         , Arg.Int (fun pid -> t.clientProcessId <- Some pid)
         , "set the pid of the lsp client" )
+      ; ( "--no-dune-diagnostics"
+        , Arg.Unit (fun () -> t.dune_diagnostics <- false)
+        , "disable dune diagnostics" )
       ]
     in
     t.spec <- spec;
@@ -52,7 +57,9 @@ module Arg = struct
 
   let clientProcessId t = t.clientProcessId
 
-  let channel { pipe; port; stdio; spec = _; clientProcessId = _ } :
+  let dune_diagnostics t = t.dune_diagnostics
+
+  let channel { pipe; port; stdio; spec = _; clientProcessId = _; dune_diagnostics = _ } :
       (Channel.t, string) result =
     match (pipe, port, stdio) with
     | None, None, _ -> Ok Stdio
@@ -61,12 +68,18 @@ module Arg = struct
     | _, _, _ -> Error "invalid arguments"
 end
 
-let args ?channel ?clientProcessId () =
+let args ?channel ?clientProcessId ?(duneDiagnostics = true) () =
   let args =
     match clientProcessId with
     | None -> []
+    (* TODO: typo? *)
     | Some pid -> [ "--clientPorcessId"; string_of_int pid ]
   in
+  let args =
+    match duneDiagnostics with
+    | true -> args
+    | false -> "--no-dune-diagnostics" :: args
+  in
   match (channel : Channel.t option) with
   | None -> args
   | Some Stdio -> "--stdio" :: args

lsp/src/cli.mli

@@ -28,7 +28,11 @@ module Arg : sig
   (** Return the process id of the client used to run the lsp server if it was
       provided *)
   val clientProcessId : t -> int option
+
+
+  (** [dune diagnostics t] True if the dune diagnostics loop should be enabled *)
+  val dune_diagnostics : t -> bool
 end
 
 (** generate command line arguments that can be used to spawn an lsp client *)
-val args : ?channel:Channel.t -> ?clientProcessId:int -> unit -> string list
+val args : ?channel:Channel.t -> ?clientProcessId:int -> ?duneDiagnostics:bool -> unit -> string list

ocaml-lsp-server/bin/main.ml

@@ -5,23 +5,19 @@ let () =
   Printexc.record_backtrace true;
   let version = ref false in
   let read_dot_merlin = ref false in
-  let dune_diagnostics = ref true in
   let arg = Lsp.Cli.Arg.create () in
   let spec =
     [ ("--version", Arg.Set version, "print version")
     ; ( "--fallback-read-dot-merlin"
       , Arg.Set read_dot_merlin
       , "read Merlin config from .merlin files. The `dot-merlin-reader` \
          package must be installed" )
-    ; ( "--no-dune-diagnostics"
-      , Arg.Clear dune_diagnostics
-      , "disable dune diagnostics" )
     ]
     @ Cli.Arg.spec arg
   in
   let usage =
     "ocamllsp [ --stdio | --socket PORT | --port PORT | --pipe PIPE ] [ \
-     --clientProcessId pid ]"
+     --clientProcessId pid ] [ --no-dune-diagnostics ]"
   in
   Arg.parse
     spec
@@ -46,7 +42,7 @@ let () =
         (Ocaml_lsp_server.run
            channel
            ~read_dot_merlin:!read_dot_merlin
-           ~dune_diagnostics:!dune_diagnostics)
+           ~dune_diagnostics:(Cli.Arg.dune_diagnostics arg))
     with
     | Ok () -> ()
     | Error exn ->