MetaFilter number all comments

On MetaFilter.com, adds a comment number like "comment 1 of 30" to each comment.

ของเมื่อวันที่ 27-08-2019 ดู เวอร์ชันล่าสุด

คุณจะต้องติดตั้งส่วนขยาย เช่น Tampermonkey, Greasemonkey หรือ Violentmonkey เพื่อติดตั้งสคริปต์นี้

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

คุณจะต้องติดตั้งส่วนขยาย เช่น Tampermonkey หรือ Violentmonkey เพื่อติดตั้งสคริปต์นี้

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        MetaFilter number all comments
// @version     10
// @grant       none
// @match       http://*.metafilter.com/*
// @match       https://*.metafilter.com/*
// @description On MetaFilter.com, adds a comment number like "comment 1 of 30" to each comment.
// @locale      en-us
// @run-at      document-idle
// @namespace   https://greasyfork.org/users/324881
// ==/UserScript==

function addCountToComments() {
  // first, clear all counts in case this runs more than once on a page.
  let allCommentCountSpans = Array.from(document.getElementsByClassName('tehhundUserScriptCommentCount'));
  for (let currentSpan of allCommentCountSpans) { currentSpan.remove(); }

  // then add counts to every comment div.
  let allCommentDivs = document.getElementsByClassName('comments');
  allCommentDivs = Array.from(allCommentDivs).filter( function(div) { return div.previousSibling.tagName == 'A'; }); // Some "comment" divs are not actually comments. All comments, and only comments, are preceeded by an anchor tag. So this filters down to only real comment divs.
  for (let [i,divToHighlight] of allCommentDivs.entries()) {
    divToHighlight.lastChild.innerHTML += '<span class=\'tehhundUserScriptCommentCount\'>Comment ' + (i+1) + ' of ' + allCommentDivs.length + '. </span>';
  }
}

function runIfCommentAdded(mutationsList, observer) { // When a mutation event occurs, check if it was adding a comment and if so renumber the comments.
  for (let mutation of mutationsList) { // Loop over all mutations for this event.
    try {
      if (mutation.target.previousSibling.tagName == 'A') { // If the target's previousSibling is an anchor tag, it's probably an added comment so renumber the comments. Otherwise do nothing.
        addCountToComments();
      }
    } catch(e) { /* previousSibling is null if the mutation was adding a Favorite, and that throws an error on the console every time. This try/catch discards the error. */ }
  }
}

addCountToComments(); // Run once when the page is idle

// After the initial run, observe the main content div for changes such as new comments and run addCountToComments() again.
const mutationObserver = new MutationObserver(runIfCommentAdded);
mutationObserver.observe(document.getElementById('posts'), { attributes: true, childList: true, subtree: true })