gecko-dev/dom/html/test/browser_refresh_after_document_write.js

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

/*
Test that after using document.write(...), refreshing the document and calling write again,
resulting document.URL is identical to the original URL.

This testcase is aimed at preventing bug 619092
*/
var testURL = "http://mochi.test:8888/browser/dom/html/test/file_refresh_after_document_write.html";
let aTab, aBrowser;

function test(){
    waitForExplicitFinish();

    aTab = BrowserTestUtils.addTab(gBrowser, testURL);
    aBrowser = gBrowser.getBrowserForTab(aTab);
    BrowserTestUtils.browserLoaded(aBrowser).then(() => {
        is(aBrowser.currentURI.spec, testURL, "Make sure we start at the correct URL");

        ContentTask.spawn(aBrowser, null, () => {
          // test_btn calls document.write() then reloads the document
          let test_btn = content.document.getElementById("test_btn");

          addEventListener("load", () => {
            test_btn.click();
          }, {once: true, capture: true});

          test_btn.click();
        });

        return BrowserTestUtils.browserLoaded(aBrowser);
    }).then(() => {
        return ContentTask.spawn(aBrowser, null, () => content.document.URL);
    }).then(url => {
        is(url, testURL, "Document URL should be identical after reload");
        gBrowser.removeTab(aTab);
        finish();
    });
}