1 files changed, 35 insertions, 0 deletions
diff --git a/browser/components/sessionstore/test/browser_swapDocShells.js b/browser/components/sessionstore/test/browser_swapDocShells.js
new file mode 100644
index 000000000..839f060e7
--- /dev/null
+++ b/browser/components/sessionstore/test/browser_swapDocShells.js
@@ -0,0 +1,35 @@
+"use strict";
+
+add_task(function* () {
+  let tab = gBrowser.selectedTab = gBrowser.addTab("about:mozilla");
+  yield promiseBrowserLoaded(gBrowser.selectedBrowser);
+
+  let win = gBrowser.replaceTabWithWindow(tab);
+  yield promiseDelayedStartupFinished(win);
+  yield promiseBrowserHasURL(win.gBrowser.browsers[0], "about:mozilla");
+
+  win.duplicateTabIn(win.gBrowser.selectedTab, "tab");
+  yield promiseTabRestored(win.gBrowser.tabs[1]);
+
+  let browser = win.gBrowser.browsers[1];
+  is(browser.currentURI.spec, "about:mozilla", "tab was duplicated");
+
+  yield BrowserTestUtils.closeWindow(win);
+});
+
+function promiseDelayedStartupFinished(win) {
+  let deferred = Promise.defer();
+  whenDelayedStartupFinished(win, deferred.resolve);
+  return deferred.promise;
+}
+
+function promiseBrowserHasURL(browser, url) {
+  let promise = Promise.resolve();
+
+  if (browser.contentDocument.readyState === "complete" &&
+      browser.currentURI.spec === url) {
+    return promise;
+  }
+
+  return promise.then(() => promiseBrowserHasURL(browser, url));
+}