From 858c50695e9cf77e65a440ff39de995a43cbc2db Mon Sep 17 00:00:00 2001
From: Thomas Muldowney <thomas.muldowney@uavionix.com>
Date: Wed, 7 Feb 2024 15:10:12 -0600
Subject: [PATCH 1/4] Ensure cancel callbacks are cleaned up

---
 src/util/actor.js     | 5 ++++-
 src/util/scheduler.js | 7 +++----
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/src/util/actor.js b/src/util/actor.js
index 12c066d931a..d83727f8f12 100644
--- a/src/util/actor.js
+++ b/src/util/actor.js
@@ -113,7 +113,8 @@ class Actor {
                 // We're using a MessageChannel object to get throttle the process() flow to one at a time.
                 const callback = this.callbacks[id];
                 const metadata = (callback && callback.metadata) || {type: "message"};
-                this.cancelCallbacks[id] = this.scheduler.add(() => this.processTask(id, data), metadata);
+                const cancel = this.scheduler.add(() => this.processTask(id, data), metadata);
+                if (cancel) this.cancelCallbacks[id] = cancel;
             } else {
                 // In the main thread, process messages immediately so that other work does not slip in
                 // between getting partial data back from workers.
@@ -123,6 +124,8 @@ class Actor {
     }
 
     processTask(id: number, task: any) {
+        // Always delete since we are no longer cancellable
+        delete this.cancelCallbacks[id];
         if (task.type === '<response>') {
             // The done() function in the counterpart has been called, and we are now
             // firing the callback in the originating actor, if there is one.
diff --git a/src/util/scheduler.js b/src/util/scheduler.js
index 1b603d59431..0f7112a936c 100644
--- a/src/util/scheduler.js
+++ b/src/util/scheduler.js
@@ -38,7 +38,7 @@ class Scheduler {
         this.nextId = 0;
     }
 
-    add(fn: TaskFunction, metadata: TaskMetadata): Cancelable {
+    add(fn: TaskFunction, metadata: TaskMetadata): Cancelable | null {
         const id = this.nextId++;
         const priority = getPriority(metadata);
 
@@ -50,9 +50,8 @@ class Scheduler {
             } finally {
                 if (m) PerformanceUtils.endMeasure(m);
             }
-            return {
-                cancel: () => {}
-            };
+            // Don't return an empty cancel because we can't actually be cancelled
+            return null;
         }
 
         this.tasks[id] = {fn, metadata, priority, id};

From a5c2e4ecf662802e6b9c1bd311612da5a43520c4 Mon Sep 17 00:00:00 2001
From: Stepan Kuzmin <stepan.kuzmin@mapbox.com>
Date: Thu, 8 Feb 2024 12:04:32 +0200
Subject: [PATCH 2/4] Empty commit to trigger CI


From 0a519c1c2c982eb3702536bb1b8f42079a4aa07c Mon Sep 17 00:00:00 2001
From: Thomas Muldowney <thomas.muldowney@uavionix.com>
Date: Thu, 8 Feb 2024 10:15:17 -0600
Subject: [PATCH 3/4] Remove duplicate delete call

---
 src/util/actor.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/util/actor.js b/src/util/actor.js
index d83727f8f12..0f10ab51593 100644
--- a/src/util/actor.js
+++ b/src/util/actor.js
@@ -142,7 +142,6 @@ class Actor {
         } else {
             const buffers: Set<Transferable> = new Set();
             const done = task.hasCallback ? (err: ?Error, data: mixed) => {
-                delete this.cancelCallbacks[id];
                 this.target.postMessage({
                     id,
                     type: '<response>',

From af2f9468beb616f5f9797a9722e6566e202335dc Mon Sep 17 00:00:00 2001
From: Stepan Kuzmin <stepan.kuzmin@mapbox.com>
Date: Tue, 13 Feb 2024 12:36:32 +0200
Subject: [PATCH 4/4] Empty commit to trigger CI