hn job query search

hn_seach.js

// ==UserScript==
// @name         HN Search
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  try to take over the world!
// @author       kristopolous
// @author       lowatt
// @match        https://news.ycombinator.com/*
// @grant        none
// ==/UserScript==

(function(exports) {
	'use strict';
	function query() {
		var 
		// HN is done with very unsemantic classes.
		job_list = Array.prototype.slice.call(document.querySelectorAll('.c5a,.cae,.c00,.c9c,.cdd,.c73,.c88,.cce')),
			query_list = Array.prototype.slice.call(arguments),
			shown = 0, total = job_list.length;

		// Traverses up the dom stack trying to find a match of a specific class
		function up_to(node, klass) {
			if (node.classList.contains(klass)) {
				return node;
			} 
			if(node === document.body) {
				throw new Exception();
			}
			return up_to(node.parentNode, klass);
		}

		function display(node, what) {
			up_to(node, 'athing').style.display = what;
		}

		// If we have a RegEx, return it
		// Otherwise make it a case insensitive regex.
		function destring(what) {
			return what.test ? what : new RegExp(what.toString(), 'i');
		}

		// Hide all the postings
		job_list.forEach(function(node) {
			display(node, 'none');
		});

		query_list.forEach(function(query) {
			if (query.forEach) {
				var and_query_list = query.map(destring);

				job_list.forEach(function(node) {
					var 
					doesMatch = true, 
						toTest = node.innerHTML;

					and_query_list.forEach(function(query) {
						doesMatch &= toTest.search(query) > -1;
					})

					if(doesMatch) {
						display(node, 'block');
						shown ++;
					}
				});

			} else {
				query = destring(query);

				job_list.forEach(function(node) {
					if(node.innerHTML.search(query) > -1) {
						display(node, 'block');
						shown ++;
					}
				});
			}
		});

		return {shown: shown, total: total}
	}

	exports.q = query;
	exports.query = query;

})(window);