Bug 701377 - setTabState() always unhides the tab; r=zpao

browser/components/sessionstore/src/nsSessionStore.js

@@ -2735,6 +2735,8 @@ SessionStoreService.prototype = {
     if (aOverwriteTabs && tabbrowser.selectedTab._tPos >= newTabCount)
       tabbrowser.moveTabTo(tabbrowser.selectedTab, newTabCount - 1);
 
+    let numVisibleTabs = 0;
+
     for (var t = 0; t < newTabCount; t++) {
       tabs.push(t < openTabCount ?
                 tabbrowser.tabs[t] :
@@ -2747,10 +2749,19 @@ SessionStoreService.prototype = {
       if (winData.tabs[t].pinned)
         tabbrowser.pinTab(tabs[t]);
 
-      if (winData.tabs[t].hidden)
+      if (winData.tabs[t].hidden) {
         tabbrowser.hideTab(tabs[t]);
-      else
+      }
+      else {
         tabbrowser.showTab(tabs[t]);
+        numVisibleTabs++;
+      }
+    }
+
+    // if all tabs to be restored are hidden, make the first one visible
+    if (!numVisibleTabs && winData.tabs.length) {
+      winData.tabs[0].hidden = false;
+      tabbrowser.showTab(tabs[0]);
     }
 
     // If overwriting tabs, we want to reset each tab's "restoring" state. Since
@@ -2880,10 +2891,7 @@ SessionStoreService.prototype = {
 
     let unhiddenTabs = aTabData.filter(function (aData) !aData.hidden).length;
 
-    // if all tabs to be restored are hidden, make the first one visible
+    if (unhiddenTabs && aTabs.length > 1) {
-    if (unhiddenTabs == 0) {
-      aTabData[0].hidden = false;
-    } else if (aTabs.length > 1) {
       // Load hidden tabs last, by pushing them to the end of the list
       for (let t = 0, tabsToReorder = aTabs.length - unhiddenTabs; tabsToReorder > 0; ) {
         if (aTabData[t].hidden) {

browser/components/sessionstore/test/Makefile.in

@@ -159,6 +159,7 @@ _BROWSER_TEST_FILES = \
 	browser_687710.js \
 	browser_687710_2.js \
 	browser_694378.js \
+	browser_701377.js \
 	browser_705597.js \
 	browser_707862.js \
 	browser_739805.js \

browser/components/sessionstore/test/browser_701377.js

@@ -0,0 +1,49 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+let state = {windows:[{tabs:[
+  {entries:[{url:"http://example.com#1"}]},
+  {entries:[{url:"http://example.com#2"}], hidden: true}
+]}]};
+
+function test() {
+  waitForExplicitFinish();
+
+  newWindowWithState(state, function (aWindow) {
+    let tab = aWindow.gBrowser.tabs[1];
+    ok(tab.hidden, "the second tab is hidden");
+
+    let tabShown = false;
+    let tabShowCallback = function () tabShown = true;
+    tab.addEventListener("TabShow", tabShowCallback, false);
+
+    let tabState = ss.getTabState(tab);
+    ss.setTabState(tab, tabState);
+
+    tab.removeEventListener("TabShow", tabShowCallback, false);
+    ok(tab.hidden && !tabShown, "tab remains hidden");
+
+    finish();
+  });
+}
+
+// ----------
+function whenWindowLoaded(aWindow, aCallback) {
+  aWindow.addEventListener("load", function onLoad() {
+    aWindow.removeEventListener("load", onLoad, false);
+    executeSoon(aCallback);
+  }, false);
+}
+
+// ----------
+function newWindowWithState(aState, aCallback) {
+  let opts = "chrome,all,dialog=no,height=800,width=800";
+  let win = window.openDialog(getBrowserURL(), "_blank", opts);
+
+  registerCleanupFunction(function () win.close());
+
+  whenWindowLoaded(win, function () {
+    ss.setWindowState(win, JSON.stringify(aState), true);
+    executeSoon(function () aCallback(win));
+  });
+}