/
browser-polyfill.js
1187 lines (1136 loc) · 35.9 KB
/
browser-polyfill.js
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(function (global, factory) {
if (typeof define === "function" && define.amd) {
define("webextension-polyfill", ["module"], factory);
} else if (typeof exports !== "undefined") {
factory(module);
} else {
var mod = {
exports: {}
};
factory(mod);
global.browser = mod.exports;
}
})(this, function (module) {
/* webextension-polyfill - v0.4.0 - Wed Feb 06 2019 11:58:31 */
/* -*- Mode: indent-tabs-mode: nil; js-indent-level: 2 -*- */
/* vim: set sts=2 sw=2 et tw=80: */
/* 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";
if (typeof browser === "undefined" || Object.getPrototypeOf(browser) !== Object.prototype) {
const CHROME_SEND_MESSAGE_CALLBACK_NO_RESPONSE_MESSAGE = "The message port closed before a response was received.";
const SEND_RESPONSE_DEPRECATION_WARNING = "Returning a Promise is the preferred way to send a reply from an onMessage/onMessageExternal listener, as the sendResponse will be removed from the specs (See https://developer.mozilla.org/docs/Mozilla/Add-ons/WebExtensions/API/runtime/onMessage)";
// Wrapping the bulk of this polyfill in a one-time-use function is a minor
// optimization for Firefox. Since Spidermonkey does not fully parse the
// contents of a function until the first time it's called, and since it will
// never actually need to be called, this allows the polyfill to be included
// in Firefox nearly for free.
const wrapAPIs = extensionAPIs => {
// NOTE: apiMetadata is associated to the content of the api-metadata.json file
// at build time by replacing the following "include" with the content of the
// JSON file.
const apiMetadata = {
"alarms": {
"clear": {
"minArgs": 0,
"maxArgs": 1
},
"clearAll": {
"minArgs": 0,
"maxArgs": 0
},
"get": {
"minArgs": 0,
"maxArgs": 1
},
"getAll": {
"minArgs": 0,
"maxArgs": 0
}
},
"bookmarks": {
"create": {
"minArgs": 1,
"maxArgs": 1
},
"get": {
"minArgs": 1,
"maxArgs": 1
},
"getChildren": {
"minArgs": 1,
"maxArgs": 1
},
"getRecent": {
"minArgs": 1,
"maxArgs": 1
},
"getSubTree": {
"minArgs": 1,
"maxArgs": 1
},
"getTree": {
"minArgs": 0,
"maxArgs": 0
},
"move": {
"minArgs": 2,
"maxArgs": 2
},
"remove": {
"minArgs": 1,
"maxArgs": 1
},
"removeTree": {
"minArgs": 1,
"maxArgs": 1
},
"search": {
"minArgs": 1,
"maxArgs": 1
},
"update": {
"minArgs": 2,
"maxArgs": 2
}
},
"browserAction": {
"disable": {
"minArgs": 0,
"maxArgs": 1,
"fallbackToNoCallback": true
},
"enable": {
"minArgs": 0,
"maxArgs": 1,
"fallbackToNoCallback": true
},
"getBadgeBackgroundColor": {
"minArgs": 1,
"maxArgs": 1
},
"getBadgeText": {
"minArgs": 1,
"maxArgs": 1
},
"getPopup": {
"minArgs": 1,
"maxArgs": 1
},
"getTitle": {
"minArgs": 1,
"maxArgs": 1
},
"openPopup": {
"minArgs": 0,
"maxArgs": 0
},
"setBadgeBackgroundColor": {
"minArgs": 1,
"maxArgs": 1,
"fallbackToNoCallback": true
},
"setBadgeText": {
"minArgs": 1,
"maxArgs": 1,
"fallbackToNoCallback": true
},
"setIcon": {
"minArgs": 1,
"maxArgs": 1
},
"setPopup": {
"minArgs": 1,
"maxArgs": 1,
"fallbackToNoCallback": true
},
"setTitle": {
"minArgs": 1,
"maxArgs": 1,
"fallbackToNoCallback": true
}
},
"browsingData": {
"remove": {
"minArgs": 2,
"maxArgs": 2
},
"removeCache": {
"minArgs": 1,
"maxArgs": 1
},
"removeCookies": {
"minArgs": 1,
"maxArgs": 1
},
"removeDownloads": {
"minArgs": 1,
"maxArgs": 1
},
"removeFormData": {
"minArgs": 1,
"maxArgs": 1
},
"removeHistory": {
"minArgs": 1,
"maxArgs": 1
},
"removeLocalStorage": {
"minArgs": 1,
"maxArgs": 1
},
"removePasswords": {
"minArgs": 1,
"maxArgs": 1
},
"removePluginData": {
"minArgs": 1,
"maxArgs": 1
},
"settings": {
"minArgs": 0,
"maxArgs": 0
}
},
"commands": {
"getAll": {
"minArgs": 0,
"maxArgs": 0
}
},
"contextMenus": {
"remove": {
"minArgs": 1,
"maxArgs": 1
},
"removeAll": {
"minArgs": 0,
"maxArgs": 0
},
"update": {
"minArgs": 2,
"maxArgs": 2
}
},
"cookies": {
"get": {
"minArgs": 1,
"maxArgs": 1
},
"getAll": {
"minArgs": 1,
"maxArgs": 1
},
"getAllCookieStores": {
"minArgs": 0,
"maxArgs": 0
},
"remove": {
"minArgs": 1,
"maxArgs": 1
},
"set": {
"minArgs": 1,
"maxArgs": 1
}
},
"devtools": {
"inspectedWindow": {
"eval": {
"minArgs": 1,
"maxArgs": 2,
"singleCallbackArg": false
}
},
"panels": {
"create": {
"minArgs": 3,
"maxArgs": 3,
"singleCallbackArg": true
}
}
},
"downloads": {
"cancel": {
"minArgs": 1,
"maxArgs": 1
},
"download": {
"minArgs": 1,
"maxArgs": 1
},
"erase": {
"minArgs": 1,
"maxArgs": 1
},
"getFileIcon": {
"minArgs": 1,
"maxArgs": 2
},
"open": {
"minArgs": 1,
"maxArgs": 1,
"fallbackToNoCallback": true
},
"pause": {
"minArgs": 1,
"maxArgs": 1
},
"removeFile": {
"minArgs": 1,
"maxArgs": 1
},
"resume": {
"minArgs": 1,
"maxArgs": 1
},
"search": {
"minArgs": 1,
"maxArgs": 1
},
"show": {
"minArgs": 1,
"maxArgs": 1,
"fallbackToNoCallback": true
}
},
"extension": {
"isAllowedFileSchemeAccess": {
"minArgs": 0,
"maxArgs": 0
},
"isAllowedIncognitoAccess": {
"minArgs": 0,
"maxArgs": 0
}
},
"history": {
"addUrl": {
"minArgs": 1,
"maxArgs": 1
},
"deleteAll": {
"minArgs": 0,
"maxArgs": 0
},
"deleteRange": {
"minArgs": 1,
"maxArgs": 1
},
"deleteUrl": {
"minArgs": 1,
"maxArgs": 1
},
"getVisits": {
"minArgs": 1,
"maxArgs": 1
},
"search": {
"minArgs": 1,
"maxArgs": 1
}
},
"i18n": {
"detectLanguage": {
"minArgs": 1,
"maxArgs": 1
},
"getAcceptLanguages": {
"minArgs": 0,
"maxArgs": 0
}
},
"identity": {
"launchWebAuthFlow": {
"minArgs": 1,
"maxArgs": 1
}
},
"idle": {
"queryState": {
"minArgs": 1,
"maxArgs": 1
}
},
"management": {
"get": {
"minArgs": 1,
"maxArgs": 1
},
"getAll": {
"minArgs": 0,
"maxArgs": 0
},
"getSelf": {
"minArgs": 0,
"maxArgs": 0
},
"setEnabled": {
"minArgs": 2,
"maxArgs": 2
},
"uninstallSelf": {
"minArgs": 0,
"maxArgs": 1
}
},
"notifications": {
"clear": {
"minArgs": 1,
"maxArgs": 1
},
"create": {
"minArgs": 1,
"maxArgs": 2
},
"getAll": {
"minArgs": 0,
"maxArgs": 0
},
"getPermissionLevel": {
"minArgs": 0,
"maxArgs": 0
},
"update": {
"minArgs": 2,
"maxArgs": 2
}
},
"pageAction": {
"getPopup": {
"minArgs": 1,
"maxArgs": 1
},
"getTitle": {
"minArgs": 1,
"maxArgs": 1
},
"hide": {
"minArgs": 1,
"maxArgs": 1,
"fallbackToNoCallback": true
},
"setIcon": {
"minArgs": 1,
"maxArgs": 1
},
"setPopup": {
"minArgs": 1,
"maxArgs": 1,
"fallbackToNoCallback": true
},
"setTitle": {
"minArgs": 1,
"maxArgs": 1,
"fallbackToNoCallback": true
},
"show": {
"minArgs": 1,
"maxArgs": 1,
"fallbackToNoCallback": true
}
},
"permissions": {
"contains": {
"minArgs": 1,
"maxArgs": 1
},
"getAll": {
"minArgs": 0,
"maxArgs": 0
},
"remove": {
"minArgs": 1,
"maxArgs": 1
},
"request": {
"minArgs": 1,
"maxArgs": 1
}
},
"runtime": {
"getBackgroundPage": {
"minArgs": 0,
"maxArgs": 0
},
"getBrowserInfo": {
"minArgs": 0,
"maxArgs": 0
},
"getPlatformInfo": {
"minArgs": 0,
"maxArgs": 0
},
"openOptionsPage": {
"minArgs": 0,
"maxArgs": 0
},
"requestUpdateCheck": {
"minArgs": 0,
"maxArgs": 0
},
"sendMessage": {
"minArgs": 1,
"maxArgs": 3
},
"sendNativeMessage": {
"minArgs": 2,
"maxArgs": 2
},
"setUninstallURL": {
"minArgs": 1,
"maxArgs": 1
}
},
"sessions": {
"getDevices": {
"minArgs": 0,
"maxArgs": 1
},
"getRecentlyClosed": {
"minArgs": 0,
"maxArgs": 1
},
"restore": {
"minArgs": 0,
"maxArgs": 1
}
},
"storage": {
"local": {
"clear": {
"minArgs": 0,
"maxArgs": 0
},
"get": {
"minArgs": 0,
"maxArgs": 1
},
"getBytesInUse": {
"minArgs": 0,
"maxArgs": 1
},
"remove": {
"minArgs": 1,
"maxArgs": 1
},
"set": {
"minArgs": 1,
"maxArgs": 1
}
},
"managed": {
"get": {
"minArgs": 0,
"maxArgs": 1
},
"getBytesInUse": {
"minArgs": 0,
"maxArgs": 1
}
},
"sync": {
"clear": {
"minArgs": 0,
"maxArgs": 0
},
"get": {
"minArgs": 0,
"maxArgs": 1
},
"getBytesInUse": {
"minArgs": 0,
"maxArgs": 1
},
"remove": {
"minArgs": 1,
"maxArgs": 1
},
"set": {
"minArgs": 1,
"maxArgs": 1
}
}
},
"tabs": {
"captureVisibleTab": {
"minArgs": 0,
"maxArgs": 2
},
"create": {
"minArgs": 1,
"maxArgs": 1
},
"detectLanguage": {
"minArgs": 0,
"maxArgs": 1
},
"discard": {
"minArgs": 0,
"maxArgs": 1
},
"duplicate": {
"minArgs": 1,
"maxArgs": 1
},
"executeScript": {
"minArgs": 1,
"maxArgs": 2
},
"get": {
"minArgs": 1,
"maxArgs": 1
},
"getCurrent": {
"minArgs": 0,
"maxArgs": 0
},
"getZoom": {
"minArgs": 0,
"maxArgs": 1
},
"getZoomSettings": {
"minArgs": 0,
"maxArgs": 1
},
"highlight": {
"minArgs": 1,
"maxArgs": 1
},
"insertCSS": {
"minArgs": 1,
"maxArgs": 2
},
"move": {
"minArgs": 2,
"maxArgs": 2
},
"query": {
"minArgs": 1,
"maxArgs": 1
},
"reload": {
"minArgs": 0,
"maxArgs": 2
},
"remove": {
"minArgs": 1,
"maxArgs": 1
},
"removeCSS": {
"minArgs": 1,
"maxArgs": 2
},
"sendMessage": {
"minArgs": 2,
"maxArgs": 3
},
"setZoom": {
"minArgs": 1,
"maxArgs": 2
},
"setZoomSettings": {
"minArgs": 1,
"maxArgs": 2
},
"update": {
"minArgs": 1,
"maxArgs": 2
}
},
"topSites": {
"get": {
"minArgs": 0,
"maxArgs": 0
}
},
"webNavigation": {
"getAllFrames": {
"minArgs": 1,
"maxArgs": 1
},
"getFrame": {
"minArgs": 1,
"maxArgs": 1
}
},
"webRequest": {
"handlerBehaviorChanged": {
"minArgs": 0,
"maxArgs": 0
}
},
"windows": {
"create": {
"minArgs": 0,
"maxArgs": 1
},
"get": {
"minArgs": 1,
"maxArgs": 2
},
"getAll": {
"minArgs": 0,
"maxArgs": 1
},
"getCurrent": {
"minArgs": 0,
"maxArgs": 1
},
"getLastFocused": {
"minArgs": 0,
"maxArgs": 1
},
"remove": {
"minArgs": 1,
"maxArgs": 1
},
"update": {
"minArgs": 2,
"maxArgs": 2
}
}
};
if (Object.keys(apiMetadata).length === 0) {
throw new Error("api-metadata.json has not been included in browser-polyfill");
}
/**
* A WeakMap subclass which creates and stores a value for any key which does
* not exist when accessed, but behaves exactly as an ordinary WeakMap
* otherwise.
*
* @param {function} createItem
* A function which will be called in order to create the value for any
* key which does not exist, the first time it is accessed. The
* function receives, as its only argument, the key being created.
*/
class DefaultWeakMap extends WeakMap {
constructor(createItem, items = undefined) {
super(items);
this.createItem = createItem;
}
get(key) {
if (!this.has(key)) {
this.set(key, this.createItem(key));
}
return super.get(key);
}
}
/**
* Returns true if the given object is an object with a `then` method, and can
* therefore be assumed to behave as a Promise.
*
* @param {*} value The value to test.
* @returns {boolean} True if the value is thenable.
*/
const isThenable = value => {
return value && typeof value === "object" && typeof value.then === "function";
};
/**
* Creates and returns a function which, when called, will resolve or reject
* the given promise based on how it is called:
*
* - If, when called, `chrome.runtime.lastError` contains a non-null object,
* the promise is rejected with that value.
* - If the function is called with exactly one argument, the promise is
* resolved to that value.
* - Otherwise, the promise is resolved to an array containing all of the
* function's arguments.
*
* @param {object} promise
* An object containing the resolution and rejection functions of a
* promise.
* @param {function} promise.resolve
* The promise's resolution function.
* @param {function} promise.rejection
* The promise's rejection function.
* @param {object} metadata
* Metadata about the wrapped method which has created the callback.
* @param {integer} metadata.maxResolvedArgs
* The maximum number of arguments which may be passed to the
* callback created by the wrapped async function.
*
* @returns {function}
* The generated callback function.
*/
const makeCallback = (promise, metadata) => {
return (...callbackArgs) => {
if (extensionAPIs.runtime.lastError) {
promise.reject(extensionAPIs.runtime.lastError);
} else if (metadata.singleCallbackArg || callbackArgs.length <= 1 && metadata.singleCallbackArg !== false) {
promise.resolve(callbackArgs[0]);
} else {
promise.resolve(callbackArgs);
}
};
};
const pluralizeArguments = numArgs => numArgs == 1 ? "argument" : "arguments";
/**
* Creates a wrapper function for a method with the given name and metadata.
*
* @param {string} name
* The name of the method which is being wrapped.
* @param {object} metadata
* Metadata about the method being wrapped.
* @param {integer} metadata.minArgs
* The minimum number of arguments which must be passed to the
* function. If called with fewer than this number of arguments, the
* wrapper will raise an exception.
* @param {integer} metadata.maxArgs
* The maximum number of arguments which may be passed to the
* function. If called with more than this number of arguments, the
* wrapper will raise an exception.
* @param {integer} metadata.maxResolvedArgs
* The maximum number of arguments which may be passed to the
* callback created by the wrapped async function.
*
* @returns {function(object, ...*)}
* The generated wrapper function.
*/
const wrapAsyncFunction = (name, metadata) => {
return function asyncFunctionWrapper(target, ...args) {
if (args.length < metadata.minArgs) {
throw new Error(`Expected at least ${metadata.minArgs} ${pluralizeArguments(metadata.minArgs)} for ${name}(), got ${args.length}`);
}
if (args.length > metadata.maxArgs) {
throw new Error(`Expected at most ${metadata.maxArgs} ${pluralizeArguments(metadata.maxArgs)} for ${name}(), got ${args.length}`);
}
return new Promise((resolve, reject) => {
if (metadata.fallbackToNoCallback) {
// This API method has currently no callback on Chrome, but it return a promise on Firefox,
// and so the polyfill will try to call it with a callback first, and it will fallback
// to not passing the callback if the first call fails.
try {
target[name](...args, makeCallback({ resolve, reject }, metadata));
} catch (cbError) {
console.warn(`${name} API method doesn't seem to support the callback parameter, ` + "falling back to call it without a callback: ", cbError);
target[name](...args);
// Update the API method metadata, so that the next API calls will not try to
// use the unsupported callback anymore.
metadata.fallbackToNoCallback = false;
metadata.noCallback = true;
resolve();
}
} else if (metadata.noCallback) {
target[name](...args);
resolve();
} else {
target[name](...args, makeCallback({ resolve, reject }, metadata));
}
});
};
};
/**
* Wraps an existing method of the target object, so that calls to it are
* intercepted by the given wrapper function. The wrapper function receives,
* as its first argument, the original `target` object, followed by each of
* the arguments passed to the original method.
*
* @param {object} target
* The original target object that the wrapped method belongs to.
* @param {function} method
* The method being wrapped. This is used as the target of the Proxy
* object which is created to wrap the method.
* @param {function} wrapper
* The wrapper function which is called in place of a direct invocation
* of the wrapped method.
*
* @returns {Proxy<function>}
* A Proxy object for the given method, which invokes the given wrapper
* method in its place.
*/
const wrapMethod = (target, method, wrapper) => {
return new Proxy(method, {
apply(targetMethod, thisObj, args) {
return wrapper.call(thisObj, target, ...args);
}
});
};
let hasOwnProperty = Function.call.bind(Object.prototype.hasOwnProperty);
/**
* Wraps an object in a Proxy which intercepts and wraps certain methods
* based on the given `wrappers` and `metadata` objects.
*
* @param {object} target
* The target object to wrap.
*
* @param {object} [wrappers = {}]
* An object tree containing wrapper functions for special cases. Any
* function present in this object tree is called in place of the
* method in the same location in the `target` object tree. These
* wrapper methods are invoked as described in {@see wrapMethod}.
*
* @param {object} [metadata = {}]
* An object tree containing metadata used to automatically generate
* Promise-based wrapper functions for asynchronous. Any function in
* the `target` object tree which has a corresponding metadata object
* in the same location in the `metadata` tree is replaced with an
* automatically-generated wrapper function, as described in
* {@see wrapAsyncFunction}
*
* @returns {Proxy<object>}
*/
const wrapObject = (target, wrappers = {}, metadata = {}) => {
let cache = Object.create(null);
let handlers = {
has(proxyTarget, prop) {
return prop in target || prop in cache;
},
get(proxyTarget, prop, receiver) {
if (prop in cache) {
return cache[prop];
}
if (!(prop in target)) {
return undefined;
}
let value = target[prop];
if (typeof value === "function") {
// This is a method on the underlying object. Check if we need to do
// any wrapping.
if (typeof wrappers[prop] === "function") {
// We have a special-case wrapper for this method.
value = wrapMethod(target, target[prop], wrappers[prop]);
} else if (hasOwnProperty(metadata, prop)) {
// This is an async method that we have metadata for. Create a
// Promise wrapper for it.
let wrapper = wrapAsyncFunction(prop, metadata[prop]);
value = wrapMethod(target, target[prop], wrapper);
} else {
// This is a method that we don't know or care about. Return the
// original method, bound to the underlying object.
value = value.bind(target);
}
} else if (typeof value === "object" && value !== null && (hasOwnProperty(wrappers, prop) || hasOwnProperty(metadata, prop))) {
// This is an object that we need to do some wrapping for the children
// of. Create a sub-object wrapper for it with the appropriate child
// metadata.
value = wrapObject(value, wrappers[prop], metadata[prop]);
} else {
// We don't need to do any wrapping for this property,
// so just forward all access to the underlying object.
Object.defineProperty(cache, prop, {
configurable: true,
enumerable: true,
get() {
return target[prop];
},
set(value) {
target[prop] = value;
}
});
return value;
}
cache[prop] = value;
return value;
},
set(proxyTarget, prop, value, receiver) {
if (prop in cache) {
cache[prop] = value;
} else {
target[prop] = value;
}
return true;
},
defineProperty(proxyTarget, prop, desc) {
return Reflect.defineProperty(cache, prop, desc);
},
deleteProperty(proxyTarget, prop) {
return Reflect.deleteProperty(cache, prop);
}
};
// Per contract of the Proxy API, the "get" proxy handler must return the
// original value of the target if that value is declared read-only and
// non-configurable. For this reason, we create an object with the
// prototype set to `target` instead of using `target` directly.
// Otherwise we cannot return a custom object for APIs that
// are declared read-only and non-configurable, such as `chrome.devtools`.
//
// The proxy handlers themselves will still use the original `target`
// instead of the `proxyTarget`, so that the methods and properties are
// dereferenced via the original targets.
let proxyTarget = Object.create(target);
return new Proxy(proxyTarget, handlers);
};
/**
* Creates a set of wrapper functions for an event object, which handles
* wrapping of listener functions that those messages are passed.
*
* A single wrapper is created for each listener function, and stored in a
* map. Subsequent calls to `addListener`, `hasListener`, or `removeListener`
* retrieve the original wrapper, so that attempts to remove a
* previously-added listener work as expected.
*
* @param {DefaultWeakMap<function, function>} wrapperMap
* A DefaultWeakMap object which will create the appropriate wrapper
* for a given listener function when one does not exist, and retrieve
* an existing one when it does.
*
* @returns {object}
*/