compatibility with lwt 6 (#128)

* compatibility with lwt 6

* try to work for lwt 5 and lwt 6

* CI: try lwt 5 then lwt 6

* only try lwt 6 on OCaml >= 5

* relax lwt bounds

* more robust dune rule

* CI

---------

Co-authored-by: Simon Cruanes <simon.cruanes.2007@m4x.org>

.github/workflows/main.yml

@@ -42,10 +42,8 @@ jobs:
           allow-prerelease-opam: true
 
       - run: |
-          opam pin trace https://github.com/ocaml-tracing/ocaml-trace.git#main -y -n
-          opam pin https://github.com/ocaml-tracing/ambient-context.git#HEAD -y -n
           opam install pbrt.4.0 -y
-          opam install ambient-context
+          opam install ambient-context lwt.5.9.2
 
       # We cannot install packages that need eio on ocaml versions before 5
       - run: |
@@ -62,6 +60,11 @@ jobs:
       - run: opam install trace
       - run: opam exec -- dune build @install -p opentelemetry
 
+      - run: opam install lwt.6.1.1 -y
+        if: ${{ matrix.ocaml-compiler == '5.3.x' }}
+      - run: opam exec -- dune build @install -p opentelemetry,opentelemetry-client,opentelemetry-lwt,opentelemetry-client-cohttp-lwt
+        if: ${{ matrix.ocaml-compiler == '5.3.x' }}
+
       - run: opam install ocaml-protoc
       - run: opam exec -- dune build @lint
 

src/client/lwt/dune

@@ -25,3 +25,19 @@
   mtime.clock.os
   lwt.unix)
  (synopsis "Lwt-specific helpers for opentelemetry-client"))
+
+(rule
+ (enabled_if
+  (and
+   %{lib-available:lwt}
+   (>= %{version:lwt} 6.0)))
+ (action
+  (copy types_.ml.6 types_.ml)))
+
+(rule
+ (enabled_if
+  (and
+   %{lib-available:lwt}
+   (< %{version:lwt} 6.0)))
+ (action
+  (copy types_.ml.5 types_.ml)))

src/client/lwt/notifier_lwt.ml

@@ -5,7 +5,7 @@ module IO = Io_lwt
 type t = {
   notified: bool Atomic.t;
   cond: unit Lwt_condition.t;
-  notification: int;
+  notification: Types_.notification;
   lwt_tid: int;  (** thread ID where lwt runs *)
   deleted: bool Atomic.t;
 }

src/client/lwt/types_.ml.5

@@ -0,0 +1,2 @@
+
+type notification = int

src/client/lwt/types_.ml.6

@@ -0,0 +1,2 @@
+
+type notification = Lwt_unix.notification