Bug 1823670 - [messagehandler] Destroy MessageHandlers when pages move to... (0232a50a) · Commits · clairehurst / Tor Browser

remote/shared/messagehandler/test/browser/browser.ini

+1 −0

Original line number	Diff line number	Diff line
		@@ -7,6 +7,7 @@ support-files =
		prefs =
		remote.messagehandler.modulecache.useBrowserTestRoot=true

		[browser_bfcache.js]
		[browser_events_dispatcher.js]
		[browser_events_handler.js]
		[browser_events_module.js]

remote/shared/messagehandler/test/browser/browser_bfcache.js

0 → 100644

+98 −0

Original line number	Diff line number	Diff line
		/* Any copyright is dedicated to the Public Domain.
		* http://creativecommons.org/publicdomain/zero/1.0/ */

		"use strict";

		const { RootMessageHandler } = ChromeUtils.importESModule(
		"chrome://remote/content/shared/messagehandler/RootMessageHandler.sys.mjs"
		);

		const TEST_PREF = "remote.messagehandler.test.pref";

		// Check that pages in bfcache no longer have message handlers attached to them,
		// and that they will not emit unexpected events.
		add_task(async function test_bfcache_broadcast() {
		const tab = await addTab("https://example.com/document-builder.sjs?html=tab");
		const rootMessageHandler = createRootMessageHandler("session-id-bfcache");

		try {
		const browsingContext = tab.linkedBrowser.browsingContext;
		const contextDescriptor = {
		type: ContextDescriptorType.TopBrowsingContext,
		id: browsingContext.browserId,
		};

		// Whenever a "preference-changed" event from the eventonprefchange module
		// will be received on the root MessageHandler, increment a counter.
		let preferenceChangeEventCount = 0;
		const onEvent = (evtName, wrappedEvt) => {
		if (wrappedEvt.name === "preference-changed") {
		preferenceChangeEventCount++;
		}
		};
		rootMessageHandler.on("message-handler-event", onEvent);

		// Initialize the preference, no eventonprefchange module should be created
		// yet so preferenceChangeEventCount is not expected to be updated.
		Services.prefs.setIntPref(TEST_PREF, 0);
		await TestUtils.waitForCondition(() => preferenceChangeEventCount >= 0);
		is(preferenceChangeEventCount, 0);

		// Broadcast a "ping" command to force the creation of the eventonprefchange
		// module
		let values = await sendPingCommand(rootMessageHandler, contextDescriptor);
		is(values.length, 1, "Broadcast returned a single value");

		Services.prefs.setIntPref(TEST_PREF, 1);
		await TestUtils.waitForCondition(() => preferenceChangeEventCount >= 1);
		is(preferenceChangeEventCount, 1);

		info("Navigate to another page");
		await loadURL(
		tab.linkedBrowser,
		"https://example.com/document-builder.sjs?html=othertab"
		);

		values = await sendPingCommand(rootMessageHandler, contextDescriptor);
		is(values.length, 1, "Broadcast returned a single value after navigation");

		info("Update the preference and check we only receive 1 event");
		Services.prefs.setIntPref(TEST_PREF, 2);
		await TestUtils.waitForCondition(() => preferenceChangeEventCount >= 2);
		is(preferenceChangeEventCount, 2);

		info("Navigate to another origin");
		await loadURL(
		tab.linkedBrowser,
		"https://example.org/document-builder.sjs?html=otherorigin"
		);

		values = await sendPingCommand(rootMessageHandler, contextDescriptor);
		is(
		values.length,
		1,
		"Broadcast returned a single value after cross origin navigation"
		);

		info("Update the preference and check again that we only receive 1 event");
		Services.prefs.setIntPref(TEST_PREF, 3);
		await TestUtils.waitForCondition(() => preferenceChangeEventCount >= 3);
		is(preferenceChangeEventCount, 3);
		} finally {
		rootMessageHandler.destroy();
		gBrowser.removeTab(tab);
		Services.prefs.clearUserPref(TEST_PREF);
		}
		});

		function sendPingCommand(rootMessageHandler, contextDescriptor) {
		return rootMessageHandler.handleCommand({
		moduleName: "eventonprefchange",
		commandName: "ping",
		params: {},
		destination: {
		contextDescriptor,
		type: WindowGlobalMessageHandler.type,
		},
		});
		}

remote/shared/messagehandler/test/browser/resources/modules/windowglobal/eventonprefchange.sys.mjs

0 → 100644

+33 −0

Original line number	Diff line number	Diff line
		/* This Source Code Form is subject to the terms of the Mozilla Public
		* License, v. 2.0. If a copy of the MPL was not distributed with this
		* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

		import { Module } from "chrome://remote/content/shared/messagehandler/Module.sys.mjs";

		const TEST_PREF = "remote.messagehandler.test.pref";

		class EventOnPrefChangeModule extends Module {
		constructor(messageHandler) {
		super(messageHandler);
		Services.prefs.addObserver(TEST_PREF, this.#onPreferenceUpdated);
		}

		destroy() {
		Services.prefs.removeObserver(TEST_PREF, this.#onPreferenceUpdated);
		}

		#onPreferenceUpdated = () => {
		this.emitEvent("preference-changed");
		};

		/**
		* Commands
		*/

		ping() {
		// We only use this command to force creating the module.
		return 1;
		}
		}

		export const eventonprefchange = EventOnPrefChangeModule;

remote/shared/messagehandler/transports/js-window-actors/MessageHandlerFrameActor.sys.mjs

+2 −0

Original line number	Diff line number	Diff line
		@@ -24,6 +24,8 @@ const FRAME_ACTOR_CONFIG = {
		"chrome://remote/content/shared/messagehandler/transports/js-window-actors/MessageHandlerFrameChild.sys.mjs",
		events: {
		DOMWindowCreated: {},
		pagehide: {},
		pageshow: {},
		},
		},
		allFrames: true,

remote/shared/messagehandler/transports/js-window-actors/MessageHandlerFrameChild.sys.mjs

+8 −2

Original line number	Diff line number	Diff line
		@@ -33,11 +33,17 @@ export class MessageHandlerFrameChild extends JSWindowActorChild {
		this._registry.on("message-handler-registry-event", this._onRegistryEvent);
		}

		handleEvent({ type }) {
		if (type == "DOMWindowCreated") {
		handleEvent({ persisted, type }) {
		if (type == "DOMWindowCreated" \|\| (type == "pageshow" && persisted)) {
		// When the window is created or is retrieved from BFCache, instantiate
		// a MessageHandler for all sessions which might need it.
		if (lazy.isBrowsingContextCompatible(this.manager.browsingContext)) {
		this._registry.createAllMessageHandlers();
		}
		} else if (type == "pagehide" && persisted) {
		// When the page is moved to BFCache, all the currently created message
		// handlers should be destroyed.
		this._registry.destroy();
		}
		}