fix: custom lwt runner for js tests

1 files changed, 26 insertions, 11 deletions

diff --git a/test/js/websockets_hello.ml b/test/js/websockets_hello.ml
index 6b74d96..fa47965 100644
--- a/test/js/websockets_hello.ml
+++ b/test/js/websockets_hello.ml
@@ -1,20 +1,35 @@
 open Lwt.Syntax
+open Js_of_ocaml
+
+(* https://stackoverflow.com/questions/34929382/what-are-the-differences-between-lwt-async-and-lwt-main-run-on-ocaml-node-js *)
+let rec run t =
+  let next_tick (_callback : unit -> unit) =
+    Js.Unsafe.(fun_call
+                 (js_expr "process.nextTick")
+                 [| inject (Js.wrap_callback _callback) |])
+  in Lwt.wakeup_paused ();
+     match Lwt.poll t with
+     | Some x -> x
+     | None ->
+        if Lwt.paused_count () > 0
+        then next_tick (fun () -> run t)
+        else ()
 
 let () =
-  (* Echo is a websocket that... echoes you stuff. *)
-  let stream, push = Portal_ws.ws_stream "wss://echo.websocket.org" in
-  push (Some "great text");
-  push (Some "other text");
-  push (Some "yet another text");
-  push (Some "BYE");
-  Lwt.async @@
-    fun () ->
-    let* server = Portal_ws.ws_endpoint "egregore.fun"
-    in let+ _ = Lwt_stream.iter
+  run @@
+    let* server = Portal_ws.ws_endpoint "telepath.im" in
+    let stream, push =
+      (* Echo is a websocket that... echoes you stuff. *)
+         Portal_ws.ws_stream "wss://echo.websocket.org" in
+       push (Some "great text");
+       push (Some "other text");
+       push (Some "yet another text");
+       push (Some "BYE");
+       let+ _ = Lwt_stream.iter
                (fun greetings ->
                  match greetings with
                  (* When the websocket sends "BYE", we close. *)
                  | "BYE" -> print_endline "CLOSING BYE"; push None
                  | hello -> print_endline ("> " ^ hello))
                stream
-    in print_endline server
+       in print_endline server