Make actor.Stop(process.Abnormal(...)) exit the process with the give…

…n reason

CHANGELOG.md

@@ -1,5 +1,10 @@
 # Changelog
 
+## Unreleased
+
+- Fixed a bug where using `actor.Stop(process.Abnormal(...))` would stop
+  the process with `Normal`.
+
 ## v0.14.1 - 2024-11-15
 
 - Fixed a bug where the `significant` parameter would not be passed to the

src/gleam/otp/actor.gleam

@@ -257,6 +257,11 @@ pub type Spec(state, msg) {
 
 // TODO: Check needed functionality here to be OTP compatible
 fn exit_process(reason: ExitReason) -> ExitReason {
+  case reason {
+    Abnormal(reason) -> process.send_abnormal_exit(process.self(), reason)
+    _ -> Nil
+  }
+
   // TODO
   reason
 }
@@ -407,7 +412,7 @@ fn initialise_actor(
     // The init failed. Exit with an error.
     Failed(reason) -> {
       process.send(ack, Error(Abnormal(reason)))
-      exit_process(Abnormal(reason))
+      exit_process(process.Normal)
     }
   }
 }

test/gleam/otp/actor_test.gleam

@@ -205,6 +205,31 @@ pub fn replace_selector_test() {
   |> should.equal(dynamic.from("unknown message: String"))
 }
 
+pub fn abnormal_exit_can_be_trapped_test() {
+  process.trap_exits(True)
+  let exits =
+    process.new_selector()
+    |> process.selecting_trapped_exits(function.identity)
+
+  // Make an actor exit with an abnormal reason
+  let assert Ok(subject) =
+    actor.start(Nil, fn(_, _) { actor.Stop(process.Abnormal("reason")) })
+  process.send(subject, Nil)
+
+  let trapped_reason = process.select(exits, 10)
+
+  // Stop trapping exits, as otherwise other tests fail
+  process.trap_exits(False)
+
+  trapped_reason
+  |> should.equal(
+    Ok(process.ExitMessage(
+      process.subject_owner(subject),
+      process.Abnormal("reason"),
+    )),
+  )
+}
+
 fn mapped_selector(mapper: fn(a) -> ActorMessage) {
   let subject = process.new_subject()