/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */

// For bug 1471989, test that an exception saved by chrome code can't leak the page.

add_task(async function test() {
  const url =
    "http://mochi.test:8888/browser/js/xpconnect/tests/browser/browser_consoleStack.html";
  let newTab = await BrowserTestUtils.openNewForegroundTab(gBrowser, url);
  let browser = gBrowser.selectedBrowser;
  let innerWindowId = browser.innerWindowID;

  let stackTraceEmpty = await ContentTask.spawn(
    browser,
    { innerWindowId },
    async function(args) {
      let { TestUtils } = ChromeUtils.import(
        "resource://testing-common/TestUtils.jsm"
      );
      let { Assert } = ChromeUtils.import(
        "resource://testing-common/Assert.jsm"
      );

      const ConsoleAPIStorage = Cc[
        "@mozilla.org/consoleAPI-storage;1"
      ].getService(Ci.nsIConsoleAPIStorage);
      let consoleEvents = ConsoleAPIStorage.getEvents(args.innerWindowId);
      Assert.equal(
        consoleEvents.length,
        1,
        "Should only be one console event for the window"
      );

      // Intentionally hold a reference to the console event.
      let leakedConsoleEvent = consoleEvents[0];

      let doc = content.document;
      let promise = TestUtils.topicObserved(
        "inner-window-nuked",
        (subject, data) => {
          let id = subject.QueryInterface(Ci.nsISupportsPRUint64).data;
          return id == args.innerWindowId;
        }
      );
      content.location = "http://mochi.test:8888/";
      await promise;

      // This string should be empty. For that to happen, two things
      // need to be true:
      //
      // a) ConsoleCallData::mStack is not null. This means that the
      // stack trace was not reified before the page was nuked. If it
      // was, then the correct |filename| value would be stored on the
      // object. (This is not a problem, except that it stops us from
      // testing the next condition.)
      //
      // b) ConsoleData::mStack.mStack is null. This means that the
      // JSStackFrame is keeping alive the JS object in the page after
      // the page was nuked, which leaks the page.
      return leakedConsoleEvent.stacktrace[0].filename;
    }
  );

  is(
    stackTraceEmpty,
    "",
    "JSStackFrame shouldn't leak mStack after window nuking"
  );

  BrowserTestUtils.removeTab(newTab);
});