Sort issues/prs by most recently updated on GitHub

github-autosort-updated.user.js

// ==UserScript==
// @name        autosort-updated
// @namespace   https://github.com/olmokramer
// @description Automatically sort by updated-desc
// @include     *://github.com/*
// @version     2
// @author      Olmo Kramer
// ==/UserScript==

(function() {
	'use strict';

	function initial(arr) {
		return arr.slice(0, arr.length - 1);
	}

	function last(arr) {
		return arr[arr.length - 1];
	}

	function parseQuery(q) {
		const ret = {};

		if (!q) {
			return ret;
		}

		for (let word of q.split(' ')) {
			if (!word) {
				continue;
			}

			let [key, val] = word.split(':');

			if (!ret.hasOwnProperty(key)) {
				ret[key] = [];
			}

			ret[key].push(val);
		}

		return ret;
	}

	function stringifyQuery(q) {
		let ret = '';

		for (let [key, vals] of Object.entries(q)) {
			for (let val of vals) {
				ret += ' ' + key;
				if (val) {
					ret += ':' + val;
				}
			}
		}

		return ret.trim();
	}

	function getPageType(path) {
		const types = {
			issues: 'issue',
			pulls: 'pr',
		};

		if (last(path) == '/') {
			path = initial(path);
		}

		return types[last(path.split('/'))];
	}

	function isIssuePage(path) {
		return !!getPageType(path);
	}

	function sortByUpdatedDesc(href) {
		const url = new URL(href);

		if (!isIssuePage(url.pathname)) {
			return;
		}

		const q = parseQuery(url.searchParams.get('q'));

		// Stop if sort parameter already set.
		if (q.sort && q.sort.any(x => x)) {
			return;
		}

		q.is = q.is || [getPageType(url.pathname), 'open'];
		q.sort = ['updated-desc'];

		url.searchParams.set('q', stringifyQuery(q));

		// XXX: F-ing github doesn't respond to push/replace state...
		// history.replaceState(history.state, document.title, url.href);
		location.href = url.href;
	}

	if (MutationObserver) {
		const observer = new MutationObserver((function() {
			let href = location.href;

			return function() {
				if (location.href != href) {
					href = location.href;
					sortByUpdatedDesc(href);
				}
			};
		})());

		observer.observe(document.body, {
			childList: true,
			subtree: true,
		});
	}

	sortByUpdatedDesc(location.href);
})();