1 files changed, 182 insertions, 0 deletions
diff --git a/browser/components/sessionstore/test/browser_tab_label_during_restore.js b/browser/components/sessionstore/test/browser_tab_label_during_restore.js
new file mode 100644
index 0000000000..7108990818
--- /dev/null
+++ b/browser/components/sessionstore/test/browser_tab_label_during_restore.js
@@ -0,0 +1,182 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Test that we don't do unnecessary tab label changes while restoring a tab.
+ */
+
+add_task(async function () {
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["browser.sessionstore.restore_on_demand", true],
+      ["browser.sessionstore.restore_tabs_lazily", true],
+    ],
+  });
+
+  const BACKUP_STATE = SessionStore.getBrowserState();
+  const REMOTE_URL = "http://www.example.com/";
+  const ABOUT_ROBOTS_URI = "about:robots";
+  const ABOUT_ROBOTS_TITLE = "Gort! Klaatu barada nikto!";
+  const NO_TITLE_URL = "data:text/plain,foo";
+  const EMPTY_TAB_TITLE = gBrowser.tabContainer.emptyTabTitle;
+
+  function observeLabelChanges(tab, expectedLabels) {
+    let seenLabels = [tab.label];
+    function TabAttrModifiedListener(event) {
+      if (event.detail.changed.some(attr => attr == "label")) {
+        seenLabels.push(tab.label);
+      }
+    }
+    tab.addEventListener("TabAttrModified", TabAttrModifiedListener);
+    return async () => {
+      await BrowserTestUtils.waitForCondition(
+        () => seenLabels.length == expectedLabels.length,
+        "saw " + seenLabels.length + " TabAttrModified events"
+      );
+      tab.removeEventListener("TabAttrModified", TabAttrModifiedListener);
+      is(
+        JSON.stringify(seenLabels),
+        JSON.stringify(expectedLabels || []),
+        "observed tab label changes"
+      );
+    };
+  }
+
+  info("setting test browser state");
+  let browserLoadedPromise = BrowserTestUtils.firstBrowserLoaded(window, false);
+  await promiseBrowserState({
+    windows: [
+      {
+        tabs: [
+          { entries: [{ url: REMOTE_URL, triggeringPrincipal_base64 }] },
+          { entries: [{ url: ABOUT_ROBOTS_URI, triggeringPrincipal_base64 }] },
+          { entries: [{ url: REMOTE_URL, triggeringPrincipal_base64 }] },
+          { entries: [{ url: NO_TITLE_URL, triggeringPrincipal_base64 }] },
+          { entries: [{ url: "about:blank", triggeringPrincipal_base64 }] },
+        ],
+      },
+    ],
+  });
+  let [tab1, tab2, tab3, tab4, tab5] = gBrowser.tabs;
+  is(gBrowser.selectedTab, tab1, "first tab is selected");
+
+  await browserLoadedPromise;
+  const REMOTE_TITLE = tab1.linkedBrowser.contentTitle;
+  is(
+    tab1.linkedBrowser.currentURI.spec,
+    REMOTE_URL,
+    "correct URL loaded in first tab"
+  );
+  is(typeof REMOTE_TITLE, "string", "content title is a string");
+  isnot(REMOTE_TITLE.length, 0, "content title isn't empty");
+  isnot(REMOTE_TITLE, REMOTE_URL, "content title is different from the URL");
+  is(tab1.label, REMOTE_TITLE, "first tab displays content title");
+  ok(
+    document.title.startsWith(REMOTE_TITLE),
+    "title bar displays content title"
+  );
+  ok(tab2.hasAttribute("pending"), "second tab is pending");
+  ok(tab3.hasAttribute("pending"), "third tab is pending");
+  ok(tab4.hasAttribute("pending"), "fourth tab is pending");
+  is(tab5.label, EMPTY_TAB_TITLE, "fifth tab dislpays empty tab title");
+
+  info("selecting the second tab");
+  // The fix for bug 1364127 caused about: pages' initial tab titles to show
+  // their about: URIs until their actual page titles are known, e.g.
+  // "about:addons" -> "Add-ons Manager". This is bug 1371896. Previously,
+  // about: pages' initial tab titles were blank until the page title was known.
+  let finishObservingLabelChanges = observeLabelChanges(tab2, [
+    ABOUT_ROBOTS_URI,
+    ABOUT_ROBOTS_TITLE,
+  ]);
+  browserLoadedPromise = BrowserTestUtils.browserLoaded(
+    tab2.linkedBrowser,
+    false,
+    ABOUT_ROBOTS_URI
+  );
+  gBrowser.selectedTab = tab2;
+  await browserLoadedPromise;
+  ok(!tab2.hasAttribute("pending"), "second tab isn't pending anymore");
+  await finishObservingLabelChanges();
+  ok(
+    document.title.startsWith(ABOUT_ROBOTS_TITLE),
+    "title bar displays content title"
+  );
+
+  info("selecting the third tab");
+  finishObservingLabelChanges = observeLabelChanges(tab3, [
+    "example.com/",
+    REMOTE_TITLE,
+  ]);
+  browserLoadedPromise = BrowserTestUtils.browserLoaded(
+    tab3.linkedBrowser,
+    false,
+    REMOTE_URL
+  );
+  gBrowser.selectedTab = tab3;
+  await browserLoadedPromise;
+  ok(!tab3.hasAttribute("pending"), "third tab isn't pending anymore");
+  await finishObservingLabelChanges();
+  ok(
+    document.title.startsWith(REMOTE_TITLE),
+    "title bar displays content title"
+  );
+
+  info("selecting the fourth tab");
+  finishObservingLabelChanges = observeLabelChanges(tab4, [NO_TITLE_URL]);
+  browserLoadedPromise = BrowserTestUtils.browserLoaded(
+    tab4.linkedBrowser,
+    false,
+    NO_TITLE_URL
+  );
+  gBrowser.selectedTab = tab4;
+  await browserLoadedPromise;
+  ok(!tab4.hasAttribute("pending"), "fourth tab isn't pending anymore");
+  await finishObservingLabelChanges();
+  is(
+    document.title,
+    document.getElementById("bundle_brand").getString("brandFullName"),
+    "title bar doesn't display content title since page doesn't have one"
+  );
+
+  info("restoring the modified browser state");
+  gBrowser.selectedTab = tab3;
+  await TabStateFlusher.flushWindow(window);
+  await promiseBrowserState(SessionStore.getBrowserState());
+  [tab1, tab2, tab3, tab4, tab5] = gBrowser.tabs;
+  is(tab3, gBrowser.selectedTab, "third tab is selected after restoring");
+  ok(
+    document.title.startsWith(REMOTE_TITLE),
+    "title bar displays content title"
+  );
+  ok(tab1.hasAttribute("pending"), "first tab is pending after restoring");
+  ok(tab2.hasAttribute("pending"), "second tab is pending after restoring");
+  is(tab2.label, ABOUT_ROBOTS_TITLE, "second tab displays content title");
+  ok(!tab3.hasAttribute("pending"), "third tab is not pending after restoring");
+  is(
+    tab3.label,
+    REMOTE_TITLE,
+    "third tab displays content title in pending state"
+  );
+  ok(tab4.hasAttribute("pending"), "fourth tab is pending after restoring");
+  is(tab4.label, NO_TITLE_URL, "fourth tab displays URL");
+  is(tab5.label, EMPTY_TAB_TITLE, "fifth tab still displays empty tab title");
+
+  info("selecting the first tab");
+  finishObservingLabelChanges = observeLabelChanges(tab1, [REMOTE_TITLE]);
+  let tabContentRestored = TestUtils.topicObserved(
+    "sessionstore-debug-tab-restored"
+  );
+  gBrowser.selectedTab = tab1;
+  ok(
+    document.title.startsWith(REMOTE_TITLE),
+    "title bar displays content title"
+  );
+  await tabContentRestored;
+  ok(!tab1.hasAttribute("pending"), "first tab isn't pending anymore");
+  await finishObservingLabelChanges();
+
+  await promiseBrowserState(BACKUP_STATE);
+});