browser/components/sessionstore/src/TabStateCache.jsm

Wed, 31 Dec 2014 07:22:50 +0100

author
Michael Schloh von Bennewitz <michael@schloh.com>
date
Wed, 31 Dec 2014 07:22:50 +0100
branch
TOR_BUG_3246
changeset 4
fc2d59ddac77
permissions
-rw-r--r--

Correct previous dual key logic pending first delivery installment.

michael@0 1 /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0 2 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0 3 * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0 4
michael@0 5 "use strict";
michael@0 6
michael@0 7 this.EXPORTED_SYMBOLS = ["TabStateCache"];
michael@0 8
michael@0 9 /**
michael@0 10 * A cache for tabs data.
michael@0 11 *
michael@0 12 * This cache implements a weak map from tabs (as XUL elements)
michael@0 13 * to tab data (as objects).
michael@0 14 *
michael@0 15 * Note that we should never cache private data, as:
michael@0 16 * - that data is used very seldom by SessionStore;
michael@0 17 * - caching private data in addition to public data is memory consuming.
michael@0 18 */
michael@0 19 this.TabStateCache = Object.freeze({
michael@0 20 /**
michael@0 21 * Retrieves cached data for a given |browser|.
michael@0 22 *
michael@0 23 * @param browser (xul:browser)
michael@0 24 * The browser to retrieve cached data for.
michael@0 25 * @return (object)
michael@0 26 * The cached data stored for the given |browser|.
michael@0 27 */
michael@0 28 get: function (browser) {
michael@0 29 return TabStateCacheInternal.get(browser);
michael@0 30 },
michael@0 31
michael@0 32 /**
michael@0 33 * Updates cached data for a given |browser|.
michael@0 34 *
michael@0 35 * @param browser (xul:browser)
michael@0 36 * The browser belonging to the given tab data.
michael@0 37 * @param newData (object)
michael@0 38 * The new data to be stored for the given |browser|.
michael@0 39 */
michael@0 40 update: function (browser, newData) {
michael@0 41 TabStateCacheInternal.update(browser, newData);
michael@0 42 }
michael@0 43 });
michael@0 44
michael@0 45 let TabStateCacheInternal = {
michael@0 46 _data: new WeakMap(),
michael@0 47
michael@0 48 /**
michael@0 49 * Retrieves cached data for a given |browser|.
michael@0 50 *
michael@0 51 * @param browser (xul:browser)
michael@0 52 * The browser to retrieve cached data for.
michael@0 53 * @return (object)
michael@0 54 * The cached data stored for the given |browser|.
michael@0 55 */
michael@0 56 get: function (browser) {
michael@0 57 return this._data.get(browser.permanentKey);
michael@0 58 },
michael@0 59
michael@0 60 /**
michael@0 61 * Updates cached data for a given |browser|.
michael@0 62 *
michael@0 63 * @param browser (xul:browser)
michael@0 64 * The browser belonging to the given tab data.
michael@0 65 * @param newData (object)
michael@0 66 * The new data to be stored for the given |browser|.
michael@0 67 */
michael@0 68 update: function (browser, newData) {
michael@0 69 let data = this._data.get(browser.permanentKey) || {};
michael@0 70
michael@0 71 for (let key of Object.keys(newData)) {
michael@0 72 let value = newData[key];
michael@0 73 if (value === null) {
michael@0 74 delete data[key];
michael@0 75 } else {
michael@0 76 data[key] = value;
michael@0 77 }
michael@0 78 }
michael@0 79
michael@0 80 this._data.set(browser.permanentKey, data);
michael@0 81 }
michael@0 82 };

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