fune/browser/base/content/test/general/browser_double_close_tab.js

/* eslint-disable mozilla/no-arbitrary-setTimeout */
"use strict";
const TEST_PAGE =
  "http://mochi.test:8888/browser/browser/base/content/test/general/file_double_close_tab.html";
var testTab;

function waitForDialog(callback) {
  function onDialogLoaded(nodeOrDialogWindow) {
    let node = nodeOrDialogWindow.document.querySelector("dialog");
    Services.obs.removeObserver(onDialogLoaded, "common-dialog-loaded");
    // Allow dialog's onLoad call to run to completion
    Promise.resolve().then(() => callback(node));
  }

  // Listen for the dialog being created
  Services.obs.addObserver(onDialogLoaded, "common-dialog-loaded");
}

function waitForDialogDestroyed(node, callback) {
  // Now listen for the dialog going away again...
  let observer = new MutationObserver(function () {
    if (!node.parentNode) {
      ok(true, "Dialog is gone");
      done();
    }
  });
  observer.observe(node.parentNode, { childList: true });

  node.ownerGlobal.addEventListener("unload", done);

  let failureTimeout = setTimeout(function () {
    ok(false, "Dialog should have been destroyed");
    done();
  }, 10000);

  function done() {
    clearTimeout(failureTimeout);
    observer.disconnect();
    observer = null;

    node.ownerGlobal.removeEventListener("unload", done);
    SimpleTest.executeSoon(callback);
  }
}

add_task(async function () {
  await SpecialPowers.pushPrefEnv({
    set: [["dom.require_user_interaction_for_beforeunload", false]],
  });

  testTab = await BrowserTestUtils.openNewForegroundTab(gBrowser, TEST_PAGE);

  // XXXgijs the reason this has nesting and callbacks rather than promises is
  // that DOM promises resolve on the next tick. So they're scheduled
  // in an event queue. So when we spin a new event queue for a modal dialog...
  // everything gets messed up and the promise's .then callbacks never get
  // called, despite resolve() being called just fine.
  await new Promise(resolveOuter => {
    waitForDialog(dialogNode => {
      waitForDialogDestroyed(dialogNode, () => {
        let doCompletion = () => setTimeout(resolveOuter, 0);
        info("Now checking if dialog is destroyed");

        ok(
          !dialogNode.ownerGlobal || dialogNode.ownerGlobal.closed,
          "onbeforeunload dialog should be gone."
        );
        if (dialogNode.ownerGlobal && !dialogNode.ownerGlobal.closed) {
          dialogNode.acceptDialog();
        }

        doCompletion();
      });
      // Click again:
      testTab.closeButton.click();
    });
    // Click once:
    testTab.closeButton.click();
  });
  await TestUtils.waitForCondition(() => !testTab.parentNode);
  ok(!testTab.parentNode, "Tab should be closed completely");
});

registerCleanupFunction(async function () {
  if (testTab.parentNode) {
    // Remove the handler, or closing this tab will prove tricky:
    try {
      await SpecialPowers.spawn(testTab.linkedBrowser, [], function () {
        content.window.onbeforeunload = null;
      });
    } catch (ex) {}
    gBrowser.removeTab(testTab);
  }
});