Run ocamllsp -version in workspace dir

This is needed when dune is managing the installation of ocamllsp, as it
needs to determine which version of ocamllsp to run by looking in the
current project's lockdir.

Signed-off-by: Stephen Sherratt <stephen@sherra.tt>

CHANGELOG.md

@@ -2,9 +2,9 @@
 
 # Unreleased
 
-- Add `ocaml.copy-type-under-cursor` to copy, in the clipboard the type of 
+- Add `ocaml.copy-type-under-cursor` to copy, in the clipboard the type of
   the expression under the cursor (#1582)
-
+- Run ocamllsp -version in workspace dir (#1641)
 - Make it a warning if ocamlc is missing (#1642)
 
 ## 1.20.1

src/extension_instance.ml

@@ -140,7 +140,13 @@ end = struct
     let ocaml_lsp_version sandbox =
       Sandbox.get_command sandbox "ocamllsp" [ "--version" ]
     in
-    Cmd.output (ocaml_lsp_version sandbox)
+    let cwd =
+      match Workspace.workspaceFolders () with
+      | [ cwd ] ->
+        Some (cwd |> WorkspaceFolder.uri |> Uri.path |> Path.of_string)
+      | _ -> None
+    in
+    Cmd.output ?cwd (ocaml_lsp_version sandbox)
     |> Promise.Result.fold
          ~ok:(fun (_ : string) -> ())
          ~error:(fun (_ : string) ->