1 files changed, 25 insertions, 0 deletions
diff --git a/browser/base/content/test/tabs/browser_bug580956.js b/browser/base/content/test/tabs/browser_bug580956.js
new file mode 100644
index 0000000000..1aa6aae129
--- /dev/null
+++ b/browser/base/content/test/tabs/browser_bug580956.js
@@ -0,0 +1,25 @@
+function numClosedTabs() {
+  return SessionStore.getClosedTabCountForWindow(window);
+}
+
+function isUndoCloseEnabled() {
+  updateTabContextMenu();
+  return !document.getElementById("context_undoCloseTab").disabled;
+}
+
+add_task(async function test() {
+  Services.prefs.setIntPref("browser.sessionstore.max_tabs_undo", 0);
+  Services.prefs.clearUserPref("browser.sessionstore.max_tabs_undo");
+  is(numClosedTabs(), 0, "There should be 0 closed tabs.");
+  ok(!isUndoCloseEnabled(), "Undo Close Tab should be disabled.");
+
+  var tab = BrowserTestUtils.addTab(gBrowser, "http://mochi.test:8888/");
+  var browser = gBrowser.getBrowserForTab(tab);
+  await BrowserTestUtils.browserLoaded(browser);
+
+  let sessionUpdatePromise = BrowserTestUtils.waitForSessionStoreUpdate(tab);
+  BrowserTestUtils.removeTab(tab);
+  await sessionUpdatePromise;
+
+  ok(isUndoCloseEnabled(), "Undo Close Tab should be enabled.");
+});