Bug 1286356 - isolate import of Console in event-emitter; r?gregtatum
MozReview-Commit-ID: HIgYdui8wwO
--- a/devtools/shared/event-emitter.js
+++ b/devtools/shared/event-emitter.js
@@ -1,66 +1,86 @@
/* 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";
(function (factory) {
+ // This file can be loaded in several different ways. It can be
+ // require()d, either from the main thread or from a worker thread;
+ // or it can be imported via Cu.import. These different forms
+ // explain some of the hairiness of this code.
+ //
+ // It's important for the devtools-as-html project that a require()
+ // on the main thread not use any chrome privileged APIs. Instead,
+ // the body of the main function can only require() (not Cu.import)
+ // modules that are available in the devtools content mode. This,
+ // plus the lack of |console| in workers, results in some gyrations
+ // in the definition of |console|.
if (this.module && module.id.indexOf("event-emitter") >= 0) {
+ let console;
+ if (isWorker) {
+ console = {
+ error: () => {}
+ };
+ } else {
+ console = this.console;
+ }
// require
- factory.call(this, require, exports, module);
+ factory.call(this, require, exports, module, console);
} else {
- // Cu.import
+ // Cu.import. This snippet implements a sort of miniature loader,
+ // which is responsible for appropriately translating require()
+ // requests from the client function. This code can use
+ // Cu.import, because it is never run in the devtools-in-content
+ // mode.
this.isWorker = false;
+ const Cu = Components.utils;
+ let console = Cu.import("resource://gre/modules/Console.jsm", {}).console;
// Bug 1259045: This module is loaded early in firefox startup as a JSM,
// but it doesn't depends on any real module. We can save a few cycles
// and bytes by not loading Loader.jsm.
let require = function (module) {
- const Cu = Components.utils;
switch (module) {
case "devtools/shared/defer":
return Cu.import("resource://gre/modules/Promise.jsm", {}).Promise.defer;
case "Services":
return Cu.import("resource://gre/modules/Services.jsm", {}).Services;
- case "resource://gre/modules/Console.jsm":
- return Cu.import("resource://gre/modules/Console.jsm", {});
case "chrome":
return {
Cu,
components: Components
};
}
return null;
};
- factory.call(this, require, this, { exports: this });
+ factory.call(this, require, this, { exports: this }, console);
this.EXPORTED_SYMBOLS = ["EventEmitter"];
}
-}).call(this, function (require, exports, module) {
+}).call(this, function (require, exports, module, console) {
+ // ⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠⚠
+ // After this point the code may not use Cu.import, and should only
+ // require() modules that are "clean-for-content".
let EventEmitter = this.EventEmitter = function () {};
module.exports = EventEmitter;
// See comment in JSM module boilerplate when adding a new dependency.
const { components } = require("chrome");
const Services = require("Services");
const defer = require("devtools/shared/defer");
let loggingEnabled = true;
- let console = {};
if (!isWorker) {
- console = require("resource://gre/modules/Console.jsm").console;
loggingEnabled = Services.prefs.getBoolPref("devtools.dump.emit");
Services.prefs.addObserver("devtools.dump.emit", {
observe: () => {
loggingEnabled = Services.prefs.getBoolPref("devtools.dump.emit");
}
}, false);
- } else {
- // Workers can't load JSMs, so we can't import Console.jsm here.
- console.error = () => {};
}
/**
* Decorate an object with event emitter functionality.
*
* @param Object objectToDecorate
* Bind all public methods of EventEmitter to
* the objectToDecorate object.