fune/devtools/client/aboutdebugging/test/browser_tabs.js

/* Any copyright is dedicated to the Public Domain.
   http://creativecommons.org/publicdomain/zero/1.0/ */

"use strict";

const TAB_URL = "data:text/html,<title>foo</title>";

add_task(function* () {
  let { tab, document } = yield openAboutDebugging("tabs");

  // Wait for initial tabs list which may be empty
  let tabsElement = getTabList(document);
  yield waitUntilElement(".target-name", tabsElement);

  // Refresh tabsElement to get the .target-list element
  tabsElement = getTabList(document);

  let names = [...tabsElement.querySelectorAll(".target-name")];
  let initialTabCount = names.length;

  info("Open a new background tab");
  let newTab = yield addTab(TAB_URL, { background: true });

  info("Wait for the tab to appear in the list with the correct name");
  let container = yield waitUntilTabContainer("foo", document);

  info("Wait until the title to update");
  yield waitUntil(() => {
    return container.querySelector(".target-name").title === TAB_URL;
  }, 100);

  // Finally, close the tab
  yield removeTab(newTab);

  info("Wait until the tab container is removed");
  yield waitUntil(() => !getTabContainer("foo", document), 100);

  // Check that the tab disappeared from the UI
  names = [...tabsElement.querySelectorAll("#tabs .target-name")];
  is(names.length, initialTabCount, "The tab disappeared from the UI");

  yield closeAboutDebugging(tab);
});

function getTabContainer(name, document) {
  let nameElements = [...document.querySelectorAll("#tabs .target-name")];
  let nameElement = nameElements.filter(element => element.textContent === name)[0];
  if (nameElement) {
    return nameElement.closest(".target-container");
  }

  return null;
}

function* waitUntilTabContainer(name, document) {
  yield waitUntil(() => {
    return getTabContainer(name, document);
  });
  return getTabContainer(name, document);
}