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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
commit26a029d407be480d791972afb5975cf62c9360a6 (patch)
treef435a8308119effd964b339f76abb83a57c29483 /devtools/client/fronts/walker.js
parentInitial commit. (diff)
downloadfirefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz
firefox-26a029d407be480d791972afb5975cf62c9360a6.zip
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+/* 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/. */
+
+"use strict";
+
+const {
+ FrontClassWithSpec,
+ types,
+ registerFront,
+} = require("resource://devtools/shared/protocol.js");
+const { walkerSpec } = require("resource://devtools/shared/specs/walker.js");
+const {
+ safeAsyncMethod,
+} = require("resource://devtools/shared/async-utils.js");
+
+/**
+ * Client side of the DOM walker.
+ */
+class WalkerFront extends FrontClassWithSpec(walkerSpec) {
+ constructor(client, targetFront, parentFront) {
+ super(client, targetFront, parentFront);
+ this._isPicking = false;
+ this._orphaned = new Set();
+ this._retainedOrphans = new Set();
+
+ // Set to true if cleanup should be requested after every mutation list.
+ this.autoCleanup = true;
+
+ this._rootNodePromise = new Promise(
+ r => (this._rootNodePromiseResolve = r)
+ );
+
+ this._onRootNodeAvailable = this._onRootNodeAvailable.bind(this);
+ this._onRootNodeDestroyed = this._onRootNodeDestroyed.bind(this);
+
+ // pick/cancelPick requests can be triggered while the Walker is being destroyed.
+ this.pick = safeAsyncMethod(this.pick.bind(this), () => this.isDestroyed());
+ this.cancelPick = safeAsyncMethod(this.cancelPick.bind(this), () =>
+ this.isDestroyed()
+ );
+
+ this.before("new-mutations", this.onMutations.bind(this));
+
+ // Those events will be emitted if watchRootNode was called on the
+ // corresponding WalkerActor, which should be handled by the ResourceCommand
+ // as long as a consumer is watching for root-node resources.
+ // This should be fixed by using watchResources directly from the walker
+ // front, either with the ROOT_NODE resource, or with the DOCUMENT_EVENT
+ // resource. See Bug 1663973.
+ this.on("root-available", this._onRootNodeAvailable);
+ this.on("root-destroyed", this._onRootNodeDestroyed);
+ }
+
+ // Update the object given a form representation off the wire.
+ form(json) {
+ this.actorID = json.actor;
+
+ // The rootNode property should usually be provided via watchRootNode.
+ // However tests are currently using the walker front without explicitly
+ // calling watchRootNode, so we keep this assignment as a fallback.
+ this.rootNode = types.getType("domnode").read(json.root, this);
+
+ this.traits = json.traits;
+ }
+
+ /**
+ * Clients can use walker.rootNode to get the current root node of the
+ * walker, but during a reload the root node might be null. This
+ * method returns a promise that will resolve to the root node when it is
+ * set.
+ */
+ async getRootNode() {
+ let rootNode = this.rootNode;
+ if (!rootNode) {
+ rootNode = await this._rootNodePromise;
+ }
+
+ return rootNode;
+ }
+
+ /**
+ * When reading an actor form off the wire, we want to hook it up to its
+ * parent or host front. The protocol guarantees that the parent will
+ * be seen by the client in either a previous or the current request.
+ * So if we've already seen this parent return it, otherwise create
+ * a bare-bones stand-in node. The stand-in node will be updated
+ * with a real form by the end of the deserialization.
+ */
+ ensureDOMNodeFront(id) {
+ const front = this.getActorByID(id);
+ if (front) {
+ return front;
+ }
+
+ return types.getType("domnode").read({ actor: id }, this, "standin");
+ }
+
+ /**
+ * See the documentation for WalkerActor.prototype.retainNode for
+ * information on retained nodes.
+ *
+ * From the client's perspective, `retainNode` can fail if the node in
+ * question is removed from the ownership tree before the `retainNode`
+ * request reaches the server. This can only happen if the client has
+ * asked the server to release nodes but hasn't gotten a response
+ * yet: Either a `releaseNode` request or a `getMutations` with `cleanup`
+ * set is outstanding.
+ *
+ * If either of those requests is outstanding AND releases the retained
+ * node, this request will fail with noSuchActor, but the ownership tree
+ * will stay in a consistent state.
+ *
+ * Because the protocol guarantees that requests will be processed and
+ * responses received in the order they were sent, we get the right
+ * semantics by setting our local retained flag on the node only AFTER
+ * a SUCCESSFUL retainNode call.
+ */
+ async retainNode(node) {
+ await super.retainNode(node);
+ node.retained = true;
+ }
+
+ async unretainNode(node) {
+ await super.unretainNode(node);
+ node.retained = false;
+ if (this._retainedOrphans.has(node)) {
+ this._retainedOrphans.delete(node);
+ this._releaseFront(node);
+ }
+ }
+
+ releaseNode(node, options = {}) {
+ // NodeFront.destroy will destroy children in the ownership tree too,
+ // mimicking what the server will do here.
+ const actorID = node.actorID;
+ this._releaseFront(node, !!options.force);
+ return super.releaseNode({ actorID });
+ }
+
+ async findInspectingNode() {
+ const response = await super.findInspectingNode();
+ return response.node;
+ }
+
+ async querySelector(queryNode, selector) {
+ const response = await super.querySelector(queryNode, selector);
+ return response.node;
+ }
+
+ async getNodeActorFromWindowID(windowID) {
+ const response = await super.getNodeActorFromWindowID(windowID);
+ return response ? response.node : null;
+ }
+
+ async getNodeActorFromContentDomReference(contentDomReference) {
+ const response = await super.getNodeActorFromContentDomReference(
+ contentDomReference
+ );
+ return response ? response.node : null;
+ }
+
+ async getStyleSheetOwnerNode(styleSheetActorID) {
+ const response = await super.getStyleSheetOwnerNode(styleSheetActorID);
+ return response ? response.node : null;
+ }
+
+ async getNodeFromActor(actorID, path) {
+ const response = await super.getNodeFromActor(actorID, path);
+ return response ? response.node : null;
+ }
+
+ _releaseFront(node, force) {
+ if (node.retained && !force) {
+ node.reparent(null);
+ this._retainedOrphans.add(node);
+ return;
+ }
+
+ if (node.retained) {
+ // Forcing a removal.
+ this._retainedOrphans.delete(node);
+ }
+
+ // Release any children
+ for (const child of node.treeChildren()) {
+ this._releaseFront(child, force);
+ }
+
+ // All children will have been removed from the node by this point.
+ node.reparent(null);
+ node.destroy();
+ }
+
+ /**
+ * Get any unprocessed mutation records and process them.
+ */
+ // eslint-disable-next-line complexity
+ async getMutations(options = {}) {
+ const mutations = await super.getMutations(options);
+ const emitMutations = [];
+ for (const change of mutations) {
+ // The target is only an actorID, get the associated front.
+ const targetID = change.target;
+ const targetFront = this.getActorByID(targetID);
+
+ if (!targetFront) {
+ console.warn(
+ "Got a mutation for an unexpected actor: " +
+ targetID +
+ ", please file a bug on bugzilla.mozilla.org!"
+ );
+ console.trace();
+ continue;
+ }
+
+ const emittedMutation = Object.assign(change, { target: targetFront });
+
+ if (change.type === "childList") {
+ // Update the ownership tree according to the mutation record.
+ const addedFronts = [];
+ const removedFronts = [];
+ for (const removed of change.removed) {
+ const removedFront = this.getActorByID(removed);
+ if (!removedFront) {
+ console.error(
+ "Got a removal of an actor we didn't know about: " + removed
+ );
+ continue;
+ }
+ // Remove from the ownership tree
+ removedFront.reparent(null);
+
+ // This node is orphaned unless we get it in the 'added' list
+ // eventually.
+ this._orphaned.add(removedFront);
+ removedFronts.push(removedFront);
+ }
+ for (const added of change.added) {
+ const addedFront = this.getActorByID(added);
+ if (!addedFront) {
+ console.error(
+ "Got an addition of an actor we didn't know " + "about: " + added
+ );
+ continue;
+ }
+ addedFront.reparent(targetFront);
+
+ // The actor is reconnected to the ownership tree, unorphan
+ // it.
+ this._orphaned.delete(addedFront);
+ addedFronts.push(addedFront);
+ }
+
+ // Before passing to users, replace the added and removed actor
+ // ids with front in the mutation record.
+ emittedMutation.added = addedFronts;
+ emittedMutation.removed = removedFronts;
+
+ // If this is coming from a DOM mutation, the actor's numChildren
+ // was passed in. Otherwise, it is simulated from a frame load or
+ // unload, so don't change the front's form.
+ if ("numChildren" in change) {
+ targetFront._form.numChildren = change.numChildren;
+ }
+ } else if (change.type === "shadowRootAttached") {
+ targetFront._form.isShadowHost = true;
+ } else if (change.type === "customElementDefined") {
+ targetFront._form.customElementLocation = change.customElementLocation;
+ } else if (change.type === "unretained") {
+ // Retained orphans were force-released without the intervention of
+ // client (probably a navigated frame).
+ for (const released of change.nodes) {
+ const releasedFront = this.getActorByID(released);
+ this._retainedOrphans.delete(released);
+ this._releaseFront(releasedFront, true);
+ }
+ } else {
+ targetFront.updateMutation(change);
+ }
+
+ // Update the inlineTextChild property of the target for a selected list of
+ // mutation types.
+ if (
+ change.type === "inlineTextChild" ||
+ change.type === "childList" ||
+ change.type === "shadowRootAttached"
+ ) {
+ if (change.inlineTextChild) {
+ targetFront.inlineTextChild = types
+ .getType("domnode")
+ .read(change.inlineTextChild, this);
+ } else {
+ targetFront.inlineTextChild = undefined;
+ }
+ }
+
+ emitMutations.push(emittedMutation);
+ }
+
+ if (options.cleanup) {
+ for (const node of this._orphaned) {
+ // This will move retained nodes to this._retainedOrphans.
+ this._releaseFront(node);
+ }
+ this._orphaned = new Set();
+ }
+
+ this.emit("mutations", emitMutations);
+ }
+
+ /**
+ * Handle the `new-mutations` notification by fetching the
+ * available mutation records.
+ */
+ onMutations() {
+ // Fetch and process the mutations.
+ this.getMutations({ cleanup: this.autoCleanup }).catch(() => {});
+ }
+
+ isLocal() {
+ return !!this.conn._transport._serverConnection;
+ }
+
+ async removeNode(node) {
+ const previousSibling = await this.previousSibling(node);
+ const nextSibling = await super.removeNode(node);
+ return {
+ previousSibling,
+ nextSibling,
+ };
+ }
+
+ async children(node, options) {
+ if (!node.useChildTargetToFetchChildren) {
+ return super.children(node, options);
+ }
+ const target = await node.connectToFrame();
+
+ // We had several issues in the past where `connectToFrame` was returning the same
+ // target as the owner document one, which led to the inspector being broken.
+ // Ultimately, we shouldn't get to this point (fix should happen in connectToFrame or
+ // on the server, e.g. for Bug 1752342), but at least this will serve as a safe guard
+ // so we don't freeze/crash the inspector.
+ if (
+ target == this.targetFront &&
+ Services.prefs.getBoolPref(
+ "devtools.testing.bypass-walker-children-iframe-guard",
+ false
+ ) !== true
+ ) {
+ console.warn("connectToFrame returned an unexpected target");
+ return {
+ nodes: [],
+ hasFirst: true,
+ hasLast: true,
+ };
+ }
+
+ const walker = (await target.getFront("inspector")).walker;
+
+ // Finally retrieve the NodeFront of the remote frame's document
+ const documentNode = await walker.getRootNode();
+
+ // Force reparenting through the remote frame boundary.
+ documentNode.reparent(node);
+
+ // And return the same kind of response `walker.children` returns
+ return {
+ nodes: [documentNode],
+ hasFirst: true,
+ hasLast: true,
+ };
+ }
+
+ /**
+ * Ensure that the RootNode of this Walker has the right parent NodeFront.
+ *
+ * This method does nothing if we are on the top level target's WalkerFront,
+ * as the RootNode won't have any parent.
+ *
+ * Otherwise, if we are in an iframe's WalkerFront, we would expect the parent
+ * of the RootNode (i.e. the NodeFront for the document loaded within the iframe)
+ * to be the <iframe>'s NodeFront. Because of fission, the two NodeFront may refer
+ * to DOM Element running in distinct processes and so the NodeFront comes from
+ * two distinct Targets and two distinct WalkerFront.
+ * This is why we need this manual "reparent" code to do the glue between the
+ * two documents.
+ */
+ async reparentRemoteFrame() {
+ const parentTarget = await this.targetFront.getParentTarget();
+ if (!parentTarget) {
+ return;
+ }
+ // Don't reparent if we are on the top target
+ if (parentTarget == this.targetFront) {
+ return;
+ }
+ // Get the NodeFront for the embedder element
+ // i.e. the <iframe> element which is hosting the document that
+ const parentWalker = (await parentTarget.getFront("inspector")).walker;
+ // As this <iframe> most likely runs in another process, we have to get it through the parent
+ // target's WalkerFront.
+ const parentNode = (
+ await parentWalker.getEmbedderElement(this.targetFront.browsingContextID)
+ ).node;
+
+ // Finally, set this embedder element's node front as the
+ const documentNode = await this.getRootNode();
+ documentNode.reparent(parentNode);
+ }
+
+ _onRootNodeAvailable(rootNode) {
+ if (rootNode.isTopLevelDocument) {
+ this.rootNode = rootNode;
+ this._rootNodePromiseResolve(this.rootNode);
+ }
+ }
+
+ _onRootNodeDestroyed(rootNode) {
+ if (rootNode.isTopLevelDocument) {
+ this._rootNodePromise = new Promise(
+ r => (this._rootNodePromiseResolve = r)
+ );
+ this.rootNode = null;
+ }
+ }
+
+ /**
+ * Start the element picker on the debuggee target.
+ * @param {Boolean} doFocus - Optionally focus the content area once the picker is
+ * activated.
+ */
+ pick(doFocus) {
+ if (this._isPicking) {
+ return Promise.resolve();
+ }
+
+ this._isPicking = true;
+
+ return super.pick(
+ doFocus,
+ this.targetFront.commands.descriptorFront.isLocalTab
+ );
+ }
+
+ /**
+ * Stop the element picker.
+ */
+ cancelPick() {
+ if (!this._isPicking) {
+ return Promise.resolve();
+ }
+
+ this._isPicking = false;
+ return super.cancelPick();
+ }
+}
+
+exports.WalkerFront = WalkerFront;
+registerFront(WalkerFront);