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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";
const REQUEST_DONE_SUFFIX = ":done";
function wait(win, type) {
return new Promise(resolve => {
const onMessage = event => {
if (event.data.type !== type) {
return;
}
win.removeEventListener("message", onMessage);
resolve();
};
win.addEventListener("message", onMessage);
});
}
/**
* Post a message to some window.
*
* @param win
* The window to post to.
* @param typeOrMessage
* Either a string or and an object representing the message to send.
* If this is a string, it will be expanded into an object with the string as the
* `type` field. If this is an object, it will be sent as is.
*/
function post(win, typeOrMessage) {
// When running unit tests on XPCShell, there is no window to send messages to.
if (!win) {
return;
}
let message = typeOrMessage;
if (typeof typeOrMessage == "string") {
message = {
type: typeOrMessage,
};
}
win.postMessage(message, "*");
}
function request(win, type) {
const done = wait(win, type + REQUEST_DONE_SUFFIX);
post(win, type);
return done;
}
exports.wait = wait;
exports.post = post;
exports.request = request;