Merge pull request #60 from kuviman/fix-eio-spawn

Make template-eio handle requests concurrently

example/template-eio/main.ml

@@ -37,7 +37,7 @@ let diagnostics (_state : state_after_processing) : Lsp.Types.Diagnostic.t list
    so that users only need to override methods that they want the server to
    actually meaningfully interpret and respond to.
 *)
-class lsp_server =
+class lsp_server ~(sw: Eio.Switch.t) =
   object (self)
     inherit Linol_eio.Jsonrpc2.server
 
@@ -45,7 +45,7 @@ class lsp_server =
     val buffers : (Lsp.Types.DocumentUri.t, state_after_processing) Hashtbl.t =
       Hashtbl.create 32
 
-    method spawn_query_handler f = Linol_eio.spawn f
+    method spawn_query_handler f = Linol_eio.spawn ~sw f
 
     (* We define here a helper method that will:
        - process a document
@@ -82,7 +82,8 @@ class lsp_server =
    and runs it as a task. *)
 let run () =
   Eio_main.run @@ fun env ->
-  let s = new lsp_server in
+  Eio.Switch.run @@ fun sw ->
+  let s = new lsp_server ~sw in
   let server = Linol_eio.Jsonrpc2.create_stdio ~env s in
   let task () =
     let shutdown () = s#get_status = `ReceivedExit in

src/eio/linol_eio.ml

@@ -52,17 +52,14 @@ module IO_eio :
 end
 
 (** Spawn function. *)
-let spawn f =
-  let promise, resolver = Eio.Promise.create () in
-  (try
-     f ();
-     Eio.Promise.resolve_ok resolver ()
+let spawn ~sw f =
+  Eio.Fiber.fork ~sw (fun () ->
+   try
+     f ()
    with exn ->
      Printf.eprintf "uncaught exception in `spawn`:\n%s\n%!"
        (Printexc.to_string exn);
-     Eio.Promise.resolve_error resolver exn);
-
-  Eio.Promise.await_exn promise
+     raise exn)
 
 include Lsp.Types
 include IO_eio