tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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ObjectActorPool.js (3482B)

      1 /* This Source Code Form is subject to the terms of the Mozilla Public
      2 * License, v. 2.0. If a copy of the MPL was not distributed with this
      3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
      4 
      5 "use strict";
      6 
      7 const { Pool } = require("devtools/shared/protocol");
      8 
      9 loader.lazyRequireGetter(
     10  this,
     11  "ObjectActor",
     12  "resource://devtools/server/actors/object.js",
     13  true
     14 );
     15 loader.lazyRequireGetter(
     16  this,
     17  "PauseScopedObjectActor",
     18  "resource://devtools/server/actors/pause-scoped.js",
     19  true
     20 );
     21 
     22 /**
     23 * A Pool dedicated to host only Object Actors for given JS values.
     24 *
     25 * It optionaly ensures that we instantate only one Object Actor
     26 * for any unique JS value.
     27 *
     28 * @param {ThreadActor} threadActor
     29 *        The related Thread Actor from which JS values are coming from.
     30 * @param {string} label
     31 *        Pool's description (for debugging purpose)
     32 * @param {boolean} uniqueActorPerValue
     33 *        Ensure instantiating only one Object Actor for each unique JS Value
     34 *        passed to createObjectGrip.
     35 */
     36 class ObjectActorPool extends Pool {
     37  constructor(threadActor, label, uniqueActorPerValue = false) {
     38    super(threadActor.conn, label);
     39    this.threadActor = threadActor;
     40 
     41    this.uniqueActorPerValue = uniqueActorPerValue;
     42  }
     43 
     44  objectActors = new WeakMap();
     45 
     46  /**
     47   * Create a grip for the given object.
     48   *
     49   * @param object object
     50   *        The object you want.
     51   * @param Number depth
     52   *        Depth of the object compared to the top level object,
     53   *        when we are inspecting nested attributes.
     54   * @param object [objectActorAttributes]
     55   *        An optional object whose properties will be assigned to the ObjectActor being created.
     56   * @return object
     57   *        The object actor form, aka "grip"
     58   */
     59  createObjectGrip(
     60    object,
     61    depth,
     62    objectActorAttributes = {},
     63  ) {
     64    // When we are creating object actors within the thread or JS tracer actor pools,
     65    // we have some caching to prevent instantiating object actors twice for the same JS object.
     66    if (this.uniqueActorPerValue) {
     67      if (this.objectActors.has(object)) {
     68        return this.objectActors.get(object).form({ depth });
     69      }
     70 
     71      // Even if we are currently creating objects actors while being paused,
     72      // in threadActor.pauseLifetimePool, we are looking into threadLifetimePool
     73      // in case we created an actor for that object *before* pausing.
     74      if (this.threadActor.threadLifetimePool.objectActors.has(object)) {
     75        return this.threadActor.threadLifetimePool.objectActors.get(object).form({ depth });
     76      }
     77    }
     78 
     79    // We instantiate PauseScopedObjectActor instances for any actor created by the Thread Actor
     80    const isGripForThreadActor = this == this.threadActor.threadLifetimePool || this == this.threadActor.pauseLifetimePool;
     81 
     82    const ActorClass = isGripForThreadActor ? PauseScopedObjectActor : ObjectActor;
     83 
     84    const actor = new ActorClass(this.threadActor, object, {
     85      // custom formatters are injecting their own attributes here
     86      ...objectActorAttributes,
     87    });
     88    this.manage(actor);
     89 
     90    if (this.uniqueActorPerValue) {
     91      this.objectActors.set(object, actor);
     92    }
     93 
     94    // Pass the current depth to form method so that it can communicate it to the previewers.
     95    // So that the actor form output may change depending on the current depth of the object within the requested preview.
     96    return actor.form({ depth });
     97  }
     98 }
     99 
    100 exports.ObjectActorPool = ObjectActorPool;