зеркало из https://github.com/mozilla/gecko-dev.git
37 строки
1.2 KiB
JavaScript
37 строки
1.2 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/. */
|
|
|
|
"use strict";
|
|
|
|
/* globals browser */
|
|
|
|
// By default, only the first handler for browser.runtime.onMessage which
|
|
// returns a value will get to return one. As such, we need to let them all
|
|
// receive the message, and all have a chance to return a response (with the
|
|
// first non-undefined result being the one that is ultimately returned).
|
|
// This way, about:compat and the shims library can both get a chance to
|
|
// process a message, and just return undefined if they wish to ignore it.
|
|
|
|
const onMessageFromTab = (function () {
|
|
const handlers = new Set();
|
|
|
|
browser.runtime.onMessage.addListener((msg, sender) => {
|
|
const promises = [...handlers.values()].map(fn => fn(msg, sender));
|
|
return Promise.allSettled(promises).then(results => {
|
|
for (const { reason, value } of results) {
|
|
if (reason) {
|
|
console.error(reason);
|
|
} else if (value !== undefined) {
|
|
return value;
|
|
}
|
|
}
|
|
return undefined;
|
|
});
|
|
});
|
|
|
|
return function (handler) {
|
|
handlers.add(handler);
|
|
};
|
|
})();
|