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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
"use strict";
/**
* This module defines custom globals injected in all our modules and also
* pseudo modules that aren't separate files but just dynamically set values.
*
* Note that some globals are being defined by base-loader.sys.mjs via wantGlobalProperties property.
*
* As it does so, the module itself doesn't have access to these globals,
* nor the pseudo modules. Be careful to avoid loading any other js module as
* they would also miss them.
*/
const systemPrincipal = Services.scriptSecurityManager.getSystemPrincipal();
/**
* Defines a getter on a specified object that will be created upon first use.
*
* @param object
* The object to define the lazy getter on.
* @param name
* The name of the getter to define on object.
* @param lambda
* A function that returns what the getter should return. This will
* only ever be called once.
*/
function defineLazyGetter(object, name, lambda) {
Object.defineProperty(object, name, {
get() {
// Redefine this accessor property as a data property.
// Delete it first, to rule out "too much recursion" in case object is
// a proxy whose defineProperty handler might unwittingly trigger this
// getter again.
delete object[name];
const value = lambda.apply(object);
Object.defineProperty(object, name, {
value,
writable: true,
configurable: true,
enumerable: true,
});
return value;
},
configurable: true,
enumerable: true,
});
}
/**
* Defines a getter on a specified object for a service. The service will not
* be obtained until first use.
*
* @param object
* The object to define the lazy getter on.
* @param name
* The name of the getter to define on object for the service.
* @param contract
* The contract used to obtain the service.
* @param interfaceName
* The name of the interface to query the service to.
*/
function defineLazyServiceGetter(object, name, contract, interfaceName) {
defineLazyGetter(object, name, function () {
return Cc[contract].getService(Ci[interfaceName]);
});
}
/**
* Define a getter property on the given object that requires the given
* module. This enables delaying importing modules until the module is
* actually used.
*
* Several getters can be defined at once by providing an array of
* properties and enabling destructuring.
*
* @param { Object } obj
* The object to define the property on.
* @param { String | Array<String> } properties
* String: Name of the property for the getter.
* Array<String>: When destructure is true, properties can be an array of
* strings to create several getters at once.
* @param { String } module
* The module path.
* @param { Boolean } destructure
* Pass true if the property name is a member of the module's exports.
*/
function lazyRequireGetter(obj, properties, module, destructure) {
if (Array.isArray(properties) && !destructure) {
throw new Error(
"Pass destructure=true to call lazyRequireGetter with an array of properties"
);
}
if (!Array.isArray(properties)) {
properties = [properties];
}
for (const property of properties) {
defineLazyGetter(obj, property, () => {
return destructure
? require(module)[property]
: require(module || property);
});
}
}
// List of pseudo modules exposed to all devtools modules.
exports.modules = {
HeapSnapshot,
// Expose "chrome" Promise, which aren't related to any document
// and so are never frozen, even if the browser loader module which
Promise,
TelemetryStopwatch,
};
defineLazyGetter(exports.modules, "Debugger", () => {
const global = Cu.getGlobalForObject(this);
// Debugger may already have been added.
if (global.Debugger) {
return global.Debugger;
}
const { addDebuggerToGlobal } = ChromeUtils.importESModule(
"resource://gre/modules/jsdebugger.sys.mjs",
{ global: "contextual" }
);
addDebuggerToGlobal(global);
return global.Debugger;
});
defineLazyGetter(exports.modules, "ChromeDebugger", () => {
// Sandbox are memory expensive, so we should create as little as possible.
const debuggerSandbox = Cu.Sandbox(systemPrincipal, {
// This sandbox is used for the ChromeDebugger implementation.
// As we want to load the `Debugger` API for debugging chrome contexts,
// we have to ensure loading it in a distinct compartment from its debuggee.
freshCompartment: true,
});
const { addDebuggerToGlobal } = ChromeUtils.importESModule(
"resource://gre/modules/jsdebugger.sys.mjs",
{ global: "contextual" }
);
addDebuggerToGlobal(debuggerSandbox);
return debuggerSandbox.Debugger;
});
defineLazyGetter(exports.modules, "xpcInspector", () => {
return Cc["@mozilla.org/jsinspector;1"].getService(Ci.nsIJSInspector);
});
// List of all custom globals exposed to devtools modules.
// Changes here should be mirrored to devtools/.eslintrc.
exports.globals = {
isWorker: false,
loader: {
lazyGetter: defineLazyGetter,
lazyServiceGetter: defineLazyServiceGetter,
lazyRequireGetter,
// Defined by Loader.sys.mjs
id: null,
},
};
// DevTools loader copy globals property descriptors on each module global
// object so that we have to memoize them from here in order to instantiate each
// global only once.
// `globals` is a cache object on which we put all global values
// and we set getters on `exports.globals` returning `globals` values.
const globals = {};
function lazyGlobal(name, getter) {
defineLazyGetter(globals, name, getter);
Object.defineProperty(exports.globals, name, {
get() {
return globals[name];
},
configurable: true,
enumerable: true,
});
}
// Lazily define a few things so that the corresponding modules are only loaded
// when used.
lazyGlobal("clearTimeout", () => {
return ChromeUtils.importESModule("resource://gre/modules/Timer.sys.mjs", {
global: "contextual",
}).clearTimeout;
});
lazyGlobal("setTimeout", () => {
return ChromeUtils.importESModule("resource://gre/modules/Timer.sys.mjs", {
global: "contextual",
}).setTimeout;
});
lazyGlobal("clearInterval", () => {
return ChromeUtils.importESModule("resource://gre/modules/Timer.sys.mjs", {
global: "contextual",
}).clearInterval;
});
lazyGlobal("setInterval", () => {
return ChromeUtils.importESModule("resource://gre/modules/Timer.sys.mjs", {
global: "contextual",
}).setInterval;
});