From deffee7c5926d6660b9268d1c93e651f0cf944ea Mon Sep 17 00:00:00 2001
From: Erik Nordin <enordin@mozilla.com>
Date: Thu, 22 May 2025 15:45:52 +0000
Subject: [PATCH] Bug 1967809 - Add more isDestroyed checks to
 TranslationsEngine actors r=translations-reviewers,gregtatum

Adds a few more checks for isDestroyed in places where we might
send asynchronous messages within the TranslationsEngine actors.

Differential Revision: https://phabricator.services.mozilla.com/D250765
---
 .../actors/TranslationsEngineChild.sys.mjs    | 23 +++++++++++++++++++
 .../actors/TranslationsEngineParent.sys.mjs   |  5 ++++
 .../actors/TranslationsParent.sys.mjs         |  5 ++++
 3 files changed, 33 insertions(+)

diff --git a/toolkit/components/translations/actors/TranslationsEngineChild.sys.mjs b/toolkit/components/translations/actors/TranslationsEngineChild.sys.mjs
index 5f351bd0facd..ee814cf389f2 100644
--- a/toolkit/components/translations/actors/TranslationsEngineChild.sys.mjs
+++ b/toolkit/components/translations/actors/TranslationsEngineChild.sys.mjs
@@ -16,6 +16,11 @@ ChromeUtils.defineESModuleGetters(lazy, {
     "chrome://global/content/translations/translations-engine.sys.mjs",
 });
 
+/**
+ * @typedef {import("../translations").LanguagePair} LanguagePair
+ * @typedef {import("../translations").TranslationsEnginePayload} TranslationsEnginePayload
+ */
+
 /**
  * The engine child is responsible for exposing privileged code to the un-privileged
  * space the engine runs in.
@@ -136,6 +141,10 @@ export class TranslationsEngineChild extends JSProcessActorChild {
     totalTranslatedWords,
     totalCompletedRequests,
   }) {
+    if (this.#isDestroyed) {
+      return;
+    }
+
     this.sendAsyncMessage("TranslationsEngine:ReportEnginePerformance", {
       sourceLanguage,
       targetLanguage,
@@ -147,8 +156,14 @@ export class TranslationsEngineChild extends JSProcessActorChild {
 
   /**
    * @param {LanguagePair} languagePair
+   *
+   * @returns {Promise<TranslationsEnginePayload> | undefined}
    */
   TE_requestEnginePayload(languagePair) {
+    if (this.#isDestroyed) {
+      return undefined;
+    }
+
     return this.sendQuery("TranslationsEngine:RequestEnginePayload", {
       languagePair,
     });
@@ -159,6 +174,10 @@ export class TranslationsEngineChild extends JSProcessActorChild {
    * @param {"ready" | "error"} status
    */
   TE_reportEngineStatus(innerWindowId, status) {
+    if (this.#isDestroyed) {
+      return;
+    }
+
     this.sendAsyncMessage("TranslationsEngine:ReportEngineStatus", {
       innerWindowId,
       status,
@@ -169,6 +188,10 @@ export class TranslationsEngineChild extends JSProcessActorChild {
    * No engines are still alive, signal that the process can be destroyed.
    */
   TE_destroyEngineProcess() {
+    if (this.#isDestroyed) {
+      return;
+    }
+
     this.sendAsyncMessage("TranslationsEngine:DestroyEngineProcess");
   }
 
diff --git a/toolkit/components/translations/actors/TranslationsEngineParent.sys.mjs b/toolkit/components/translations/actors/TranslationsEngineParent.sys.mjs
index 91165d36e1a4..dc72a89fbd8b 100644
--- a/toolkit/components/translations/actors/TranslationsEngineParent.sys.mjs
+++ b/toolkit/components/translations/actors/TranslationsEngineParent.sys.mjs
@@ -11,6 +11,7 @@ ChromeUtils.defineESModuleGetters(lazy, {
 
 /**
  * @typedef {import("../translations").LanguagePair} LanguagePair
+ * @typedef {import("../translations").TranslationsEnginePayload} TranslationsEnginePayload
  */
 
 /**
@@ -45,11 +46,15 @@ export class TranslationsEngineParent extends JSProcessActorParent {
     switch (name) {
       case "TranslationsEngine:RequestEnginePayload": {
         const { languagePair } = data;
+
+        /** @type {Promise<TranslationsEnginePayload>} */
         const payloadPromise =
           lazy.TranslationsParent.getTranslationsEnginePayload(languagePair);
+
         payloadPromise.catch(error => {
           lazy.TranslationsParent.telemetry().onError(String(error));
         });
+
         return payloadPromise;
       }
       case "TranslationsEngine:ReportEnginePerformance": {
diff --git a/toolkit/components/translations/actors/TranslationsParent.sys.mjs b/toolkit/components/translations/actors/TranslationsParent.sys.mjs
index e8ec5776a7ad..aa1c8b625c97 100644
--- a/toolkit/components/translations/actors/TranslationsParent.sys.mjs
+++ b/toolkit/components/translations/actors/TranslationsParent.sys.mjs
@@ -210,6 +210,7 @@ const VERIFY_SIGNATURES_FROM_FS = false;
  * @typedef {import("../translations").TranslationModelRecord} TranslationModelRecord
  * @typedef {import("../translations").RemoteSettingsClient} RemoteSettingsClient
  * @typedef {import("../translations").TranslationModelPayload} TranslationModelPayload
+ * @typedef {import("../translations").TranslationsEnginePayload} TranslationsEnginePayload
  * @typedef {import("../translations").LanguageTranslationModelFiles} LanguageTranslationModelFiles
  * @typedef {import("../translations").WasmRecord} WasmRecord
  * @typedef {import("../translations").LangTags} LangTags
@@ -1587,7 +1588,11 @@ export class TranslationsParent extends JSWindowActorParent {
   }
 
   /**
+   * Retrieves the payload required to construct the TranslationsEngine for the given language pair.
+   *
    * @param {LanguagePair} languagePair
+   *
+   * @returns {Promise<TranslationsEnginePayload>}
    */
   static async getTranslationsEnginePayload(languagePair) {
     const wasmStartTime = Cu.now();