Simple wrapper around `MutationObserver` API to watch DOM changes.
This script should not be not be installed directly. It is a library for other scripts to include with the meta directive // @require https://update.greasyfork.org/scripts/488160/1335044/make-mutation-observer.js
// ==UserScript==
// @name make-mutation-observer
// @description Simple wrapper around `MutationObserver` API to watch DOM changes.
// @version 0.1.0
// @namespace owowed.moe
// @author owowed <island@owowed.moe>
// @license LGPL-3.0
// ==/UserScript==
/**
* @typedef {(info: { records: MutationRecord[], observer: MutationObserver }) => void} MakeMutationObserverCallback
*/
/**
* @typedef MakeMutationObserverOptionsBasic
* @prop {HTMLElement} target
* @prop {MakeMutationObserverCallback} callback
* @prop {AbortSignal} [abortSignal]
* @prop {boolean} [once]
*/
/** @typedef {MakeMutationObserverOptionsBasic & MutationObserverInit} MakeMutationObserverOptions */
/**
* Create a new `MutationObserver` from target and callback.
* @param {Node} target target node
* @param {MakeMutationObserverCallback} callback observer callback
* @param {MakeMutationObserverOptions} options additional observer options
* @returns {MutationObserver}
*/
function makeMutationObserver(target, callback, options) {
return makeMutationObserverOptions({ target, ...options }, callback);
}
/**
* Create a new `MutationObserver` with options and callback.
* @param {MakeMutationObserverOptions} options
* @param {MakeMutationObserverCallback} callback
* @returns {MutationObserver}
*/
function makeMutationObserverOptions({ target, abortSignal, once, ...options }, callback) {
const observer = new MutationObserver(records => {
abortSignal?.throwIfAborted();
if (once) observer.disconnect();
callback({ records, observer });
});
observer.observe(target, options);
abortSignal?.addEventListener("abort", () => {
observer.disconnect();
});
return observer;
}