Rename users (especially ones with 'default' names)

RenameUser.user.js

// ==UserScript==
// @name        RenameUser
// @namespace   benjol
// @description Rename users (especially ones with 'default' names)
// @include     http://stackoverflow.com/*
// @include     http://meta.stackoverflow.com/*
// @version     1.0.0
// ==/UserScript==

function with_jquery(f) {
  var script = document.createElement("script");
  script.type = "text/javascript";
  script.textContent = "(" + f.toString() + ")(jQuery)";
  document.body.appendChild(script);
};

with_jquery(function ($) {

  //Wrap local storage access so that we avoid collisions with other scripts
  var prefix = "RenameSOUser-"
  function GetStorage(key) { return localStorage[prefix + key]; }
  function SetStorage(key, val) { localStorage[prefix + key] = val; }

  if(GetStorage("RenamesList") == null) {
    SetStorage("RenamesList", JSON.stringify({}));
  }

  var list = JSON.parse(GetStorage("RenamesList"));

  function ReplaceOn(selector, url, name, oldname) {
    var el = $(selector);
    if(name == oldname) //resetting to old name, no icons
      el.text(name);
    else if(el.attr("href") == url) //user has same name as when rename defined, tick icon
      el.html(name + " ✔");
    else //user has changed name, cross icon
      el.html(name + " ✘");
  }

  function ReplaceOne(url, name, oldname) {
    var urlprefix = url.replace(/(\/\d+\/).*/, "$1");
    var usercard = '.user-details > a[href^="' + urlprefix + '"]';
    ReplaceOn(usercard, url, name, oldname);
    var commmentOwner = 'a.comment-user[href^="' + urlprefix + '"]';
    ReplaceOn(commmentOwner, url, name, oldname);
  }

  function ReplaceAll() {
    for(var key in list) {
      ReplaceOne(list[key].url, list[key].newname, list[key].oldname);
    }
  }

  $('.post-signature:has(.user-details > a[href^="/users"])').hover(
    function () {
      $(this).addClass("bounty");
    },
    function () {
      $(this).removeClass("bounty");
    }
  );

  $('.post-signature:has(.user-details > a[href^="/users"])').on("click", function (e) {
    if(e.target.nodeName == "A" || e.target.nodeName == "IMG") return; //don't show prompt for existing links!
    var url = $(this).find(".user-details > a").attr("href");
    var urlprefix = url.replace(/(\/\d+\/).*/, "$1");
    var curname = list[urlprefix] != null ? list[urlprefix].newname : $(this).find(".user-details > a").text();
    var oldname = list[urlprefix] != null ? list[urlprefix].oldname : curname;
    var newname = prompt("New name for " + oldname + " (or leave empty to reset)", curname)
    if(newname === null) return; //cancel: do nothing
    if(newname.length == 0) { //empty: remove rename
      ReplaceOne(url, oldname, oldname); //bug here: if user has changed name, need to refresh page to properly restore
      delete list[urlprefix];
    }
    else {
      ReplaceOne(url, newname, oldname);
      list[urlprefix] = { url: url, newname: newname, oldname: oldname };
    }
    SetStorage("RenamesList", JSON.stringify(list));
  });

  ReplaceAll();
});