GitHub Diff Files Filter

A userscript that adds filters that toggle diff & PR files by extension

As of 25.03.2017. See апошняя версія.

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(I already have a user script manager, let me install it!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name          GitHub Diff Files Filter
// @version       0.1.3
// @description   A userscript that adds filters that toggle diff & PR files by extension
// @license       https://creativecommons.org/licenses/by-sa/4.0/
// @namespace     https://github.com/Mottie
// @include       https://github.com/*
// @grant         none
// @run-at        document-idle
// @author        Rob Garrison
// ==/UserScript==
(() => {
	"use strict";

	const allExtLabel = "\u00ABall\u00BB",
		noExtLabel = "\u00ABno-ext\u00BB",
		dotExtLabel = "\u00ABdot-files\u00BB";

	let list = {};

	function toggleBlocks(extension, type) {
		const files = $("#files"),
			view = type === "show" ? "" : "none";
		if (extension === allExtLabel) {
			// Toggle "all" blocks
			$$("#files div[id*='diff']").forEach(el => {
				el.style.display = view;
			});
			// update filter buttons
			$$("#files .gdf-filter a").forEach(el => {
				el.classList.toggle("selected", type === "show");
			});
		} else if (list[extension]) {
			/* list[extension] contains an array of anchor names used to target the
			 * hidden link added immediately above each file div container
			 * <a name="diff-xxxxx"></a>
			 * <div id="diff-#" class="file js-file js-details container">
			 */
			list[extension].forEach(anchor => {
				const file = $(`a[name="${anchor}"]`, files);
				if (file && file.nextElementSibling) {
					file.nextElementSibling.style.display = view;
				}
			});
		}
		updateAllButton();
	}

	function updateAllButton() {
		const buttons = $("#files .gdf-filter"),
			filters = $$("a:not(.gdf-all)", buttons),
			selected = $$("a:not(.gdf-all).selected", buttons);
		// set "all" button
		$(".gdf-all", buttons).classList.toggle(
			"selected",
			filters.length === selected.length
		);
	}

	function buildList() {
		list = {};
		// make noExtLabel the first element in the object
		list[noExtLabel] = [];
		list[dotExtLabel] = [];
		// TOC in file diffs and pr-toolbar in Pull requests
		$$("#toc > ol > li > a, .pr-toolbar .filename").forEach(file => {
			let ext,
				txt = (file.textContent || "").trim(),
				filename = txt.split("/").slice(-1)[0];
			// test for no extension, then get extension name
			// regexp from https://github.com/silverwind/file-extension
			ext = /\./.test(filename) ? /[^./\\]*$/.exec(filename)[0] : noExtLabel;
			if (ext === filename.slice(1)) {
				ext = dotExtLabel;
			}
			if (ext) {
				if (!list[ext]) {
					list[ext] = [];
				}
				list[ext].push(
					file.hash ?
						// #toc points to "a"
						file.hash.slice(1) :
						// .pr-toolbar points to "a > div > div.filename"
						closest("a", file).hash.slice(1)
				);
			}
		});
	}

	function makeFilter() {
		buildList();
		const files = $("#files");
		let filters = 0,
			keys = Object.keys(list),
			html = "Filter file extension: <div class='BtnGroup gdf-filter'>",
			btnClass = "btn btn-sm selected BtnGroup-item";
		// get length, but don't count empty arrays
		keys.forEach(ext => {
			filters += list[ext].length > 0 ? 1 : 0;
		});
		// Don't bother if only one extension is found
		if (files && filters > 1) {
			filters = document.createElement("p");
			// add a filter "all" button to the beginning
			html += `<a class="${btnClass} gdf-all" href="#">${allExtLabel}</a>`;
			keys.forEach(ext => {
				if (list[ext].length) {
					html += `<a class="${btnClass}" href="#">${ext}</a>`;
				}
			});
			// prepend filter buttons
			filters.innerHTML = html + "</div>";
			files.insertBefore(filters, files.firstChild);
			filters.addEventListener("click", event => {
				event.preventDefault();
				event.stopPropagation();
				const el = event.target;
				el.classList.toggle("selected");
				toggleBlocks(
					el.textContent.trim(),
					el.classList.contains("selected") ? "show" : "hide"
				);
			});
		}
	}

	function init() {
		if (($("#files.diff-view") || $(".pr-toolbar")) && !$(".gdf-filter")) {
			makeFilter();
		}
	}

	function $(str, el) {
		return (el || document).querySelector(str);
	}

	function $$(str, el) {
		return Array.from((el || document).querySelectorAll(str));
	}

	function closest(selector, el) {
		while (el && el.nodeType === 1) {
			if (el.matches(selector)) {
				return el;
			}
			el = el.parentNode;
		}
		return null;
	}

	document.addEventListener("pjax:end", init);
	init();

})();