github_gist_edit_link.user.js

// ==UserScript==
// @name         Github Gist Edit Link
// @namespace    https://gist.github.com/gregory-seidman/dd8b7a93f4603ef3e484c82d45809a95
// @version      1.1.0
// @description  Add an edit links on your own list page
// @downloadURL  https://gist.github.com/gregory-seidman/67c2186bdf6496f4f238209943cdc1b5/raw/github_gist_edit_link.user.js
// @updateURL    https://gist.github.com/gregory-seidman/67c2186bdf6496f4f238209943cdc1b5/raw/github_gist_edit_link.user.js
// @author       Gregory Seidman
// @match        https://gist.github.com/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=github.com
// @grant        none
// @run-at       document-idle
// ==/UserScript==

(function() {
    'use strict';
    const html = `<a class="btn btn-sm" aria-label="Edit this Gist" rel="nofollow">
        <svg aria-hidden="true" height="16" viewBox="0 0 16 16" version="1.1" width="16" data-view-component="true" class="octicon octicon-pencil">
        <path d="M11.013 1.427a1.75 1.75 0 0 1 2.474 0l1.086 1.086a1.75 1.75 0 0 1 0 2.474l-8.61 8.61c-.21.21-.47.364-.756.445l-3.251.93a.75.75 0 0 1-.927-.928l.929-3.25c.081-.286.235-.547.445-.758l8.61-8.61Zm.176 4.823L9.75 4.81l-6.286 6.287a.253.253 0 0 0-.064.108l-.558 1.953 1.953-.558a.253.253 0 0 0 .108-.064Zm1.238-3.763a.25.25 0 0 0-.354 0L10.811 3.75l1.439 1.44 1.263-1.263a.25.25 0 0 0 0-.354Z"></path>
    </svg> Edit </a>`
    const listPathRE = /^\/([^/]+)(\/|\/public|\/private)?$/;
    const endUrlRE = /\/?$/;
    let tamperTimeout = null;

    function tamper() {
        tamperTimeout = null;
        const match = listPathRE.exec(window.location.pathname);
        if (!match) {
            // not a user's gist list page
            return;
        }
        // Bonus! Get rid of the link overlay from the snippets. Why is
        // that even a thing? Nobody wants that bullshit.
        const linkOverlays = document.querySelectorAll(
            '.gist-snippet a.link-overlay');
        Array.prototype.forEach.call(linkOverlays,
                                     e => e.parentNode.removeChild(e))
        const avatar = document.querySelector(
            '.Header .Header-link.name img.avatar-user[alt^="@"]');
        if (!avatar) {
            // not logged in
            return;
        }
        const user = avatar.alt.substring(1);
        if (user.toLowerCase() !== match[1].toLowerCase()) {
            // listing another user's gists
            return;
        }
        const links = Array.prototype.slice.call(
            document.querySelectorAll(
                '.gist-snippet li a[href$="/stargazers"]'));
        for (let i=0; i<links.length; ++i) {
            const link = links[i];
            const container = document.createElement('li');
            container.innerHTML = html;
            container.className = 'd-inline-block';
            container.firstChild.href = link.href.replace(/\/stargazers$/,
                '/edit');
            link.parentNode.parentNode.appendChild(container);
        }
    }

    if (!window.history.yesIreplacedReplaceState) {
        const oldReplace = window.history.replaceState;
        function replaceState() {
            if (tamperTimeout !== null) {
                window.clearTimeout(tamperTimeout);
            }
            tamperTimeout = window.setTimeout(tamper, 100);
            return oldReplace.apply(window.history, arguments);
        }
        window.history.yesIreplaced_replaceState = true;
        window.history.replaceState = replaceState;
        tamperTimeout = window.setTimeout(tamper, 0);
    }
})();