gecko-dev/addon-sdk/source/lib/toolkit/require.js

92 строки
3.2 KiB
JavaScript

/* 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/. */
const make = (exports, rootURI, components) => {
const { Loader: { Loader, Require, Module, main } } =
components.utils.import(rootURI + "toolkit/loader.js", {});
const loader = Loader({
id: "toolkit/require",
rootURI: rootURI,
isNative: true,
paths: {
"": rootURI,
"devtools/": "resource://devtools/"
}
});
// Implement require.unload(uri) that can be used to unload
// already loaded module which is convinient during development phase.
const unload = uri => {
delete loader.sandboxes[uri];
delete loader.modules[uri];
};
const builtins = new Set(Object.keys(loader.modules));
// Below we define `require` & `require.resolve` that resolve passed
// module id relative to the caller URI. This is not perfect but good
// enough for common case & there is always an option to pass absolute
// id when that
// but presumably well enough to cover
const require = (id, options={}) => {
const { reload, all } = options;
const requirerURI = components.stack.caller.filename;
const requirer = Module(requirerURI, requirerURI);
const require = Require(loader, requirer);
if (reload) {
// To load JS code into modules, loader uses `mozIJSSubScriptLoader`
// which uses startup cache to avoid reading source from the same URI
// more than once. Unless we invalidate statup cache changes to a module
// won't be reflected even after reload. Therefor we must dispatch an
// nsIObserverService notification that causes cache invalidation.
// Note: This is not ideal since it destroys whole cache, but since there
// is no way to invalidate individual entries, we assume performance hit
// during development is acceptable.
components.classes["@mozilla.org/observer-service;1"].
getService(components.interfaces.nsIObserverService).
notifyObservers({}, "startupcache-invalidate");
if (all) {
for (let uri of Object.keys(loader.sandboxes)) {
unload(uri);
}
}
else {
unload(require.resolve(id));
}
}
return require(id);
};
require.resolve = id => {
const requirerURI = components.stack.caller.filename;
const requirer = Module(requirerURI, requirerURI);
return Require(loader, requirer).resolve(id);
};
exports.require = require;
}
// If loaded in the context of commonjs module, reload as JSM into an
// exports object.
if (typeof(require) === "function" && typeof(module) === "object") {
require("chrome").Cu.import(module.uri, module.exports);
}
// If loaded in the context of JSM make a loader & require and define
// new symbols as exported ones.
else if (typeof(__URI__) === "string" && this["Components"]) {
const builtin = Object.keys(this);
const uri = __URI__.replace("toolkit/require.js", "");
make(this, uri, this["Components"]);
this.EXPORTED_SYMBOLS = Object.
keys(this).
filter($ => builtin.indexOf($) < 0);
}
else {
throw Error("Loading require.js in this environment isn't supported")
}