Bug 651311 - Race condition in TabView._initFrame() [f=raymond, r=ian]

browser/base/content/browser-tabview.js

@@ -42,6 +42,8 @@ let TabView = {
   _window: null,
   _firstUseExperienced: false,
   _browserKeyHandlerInitialized: false,
+  _isFrameLoading: false,
+  _initFrameCallbacks: [],
   VISIBILITY_IDENTIFIER: "tabview-visibility",
 
   // ----------
@@ -128,34 +130,52 @@ let TabView = {
   // Creates the frame and calls the callback once it's loaded. 
   // If the frame already exists, calls the callback immediately. 
   _initFrame: function TabView__initFrame(callback) {
+    let hasCallback = typeof callback == "function";
+
     if (this._window) {
-      if (typeof callback == "function")
+      if (hasCallback)
         callback();
-    } else {
-      // ___ find the deck
-      this._deck = document.getElementById("tab-view-deck");
+      return;
+    }
 
-      // ___ create the frame
-      this._iframe = document.createElement("iframe");
-      this._iframe.id = "tab-view";
-      this._iframe.setAttribute("transparent", "true");
-      this._iframe.flex = 1;
+    if (hasCallback)
+      this._initFrameCallbacks.push(callback);
 
-      if (typeof callback == "function")
-        window.addEventListener("tabviewframeinitialized", callback, false);
+    if (this._isFrameLoading)
+      return;
 
-      this._iframe.setAttribute("src", "chrome://browser/content/tabview.html");
-      this._deck.appendChild(this._iframe);
-      this._window = this._iframe.contentWindow;
+    this._isFrameLoading = true;
 
-      if (this._tabShowEventListener) {
+    // ___ find the deck
+    this._deck = document.getElementById("tab-view-deck");
+
+    // ___ create the frame
+    this._iframe = document.createElement("iframe");
+    this._iframe.id = "tab-view";
+    this._iframe.setAttribute("transparent", "true");
+    this._iframe.flex = 1;
+
+    let self = this;
+
+    window.addEventListener("tabviewframeinitialized", function onInit() {
+      window.removeEventListener("tabviewframeinitialized", onInit, false);
+
+      self._isFrameLoading = false;
+      self._window = self._iframe.contentWindow;
+      self._setBrowserKeyHandlers();
+
+      if (self._tabShowEventListener) {
         gBrowser.tabContainer.removeEventListener(
-          "TabShow", this._tabShowEventListener, true);
-        this._tabShowEventListener = null;
+          "TabShow", self._tabShowEventListener, true);
+        self._tabShowEventListener = null;
       }
 
-      this._setBrowserKeyHandlers();
-    }
+      self._initFrameCallbacks.forEach(function (cb) cb());
+      self._initFrameCallbacks = [];
+    }, false);
+
+    this._iframe.setAttribute("src", "chrome://browser/content/tabview.html");
+    this._deck.appendChild(this._iframe);
   },
 
   // ----------

browser/base/content/test/tabview/Makefile.in

@@ -132,6 +132,7 @@ _BROWSER_FILES = \
                  browser_tabview_bug645653.js \
                  browser_tabview_bug649006.js \
                  browser_tabview_bug649307.js \
+                 browser_tabview_bug651311.js \
                  browser_tabview_dragdrop.js \
                  browser_tabview_exit_button.js \
                  browser_tabview_expander.js \

browser/base/content/test/tabview/browser_tabview_bug597248.js

@@ -34,7 +34,7 @@ function setupTwo(win) {
 
   // force all canvases to update, and hook in imageData save detection
   tabItems.forEach(function(tabItem) {
-    contentWindow.TabItems._update(tabItem.tab);
+    contentWindow.TabItems.update(tabItem.tab);
     tabItem.addSubscriber(tabItem, "savedCachedImageData", function(item) {
       item.removeSubscriber(item, "savedCachedImageData");
       --numTabsToSave;
@@ -70,8 +70,7 @@ function setupTwo(win) {
           restoredWin.removeEventListener(
             "tabviewframeinitialized", onTabViewFrameInitialized, false);
 
-          let restoredContentWindow =
-            restoredWin.document.getElementById("tab-view").contentWindow;
+          let restoredContentWindow = restoredWin.TabView.getContentWindow();
           // prevent TabItems._update being called before checking cached images
           restoredContentWindow.TabItems._pauseUpdateForTest = true;
 
@@ -134,8 +133,7 @@ let gTabsProgressListener = {
 
 function updateAndCheck() {
   // force all canvas to update
-  let contentWindow = 
-    restoredWin.document.getElementById("tab-view").contentWindow;
+  let contentWindow = restoredWin.TabView.getContentWindow();
 
   contentWindow.TabItems._pauseUpdateForTest = false;
 

browser/base/content/test/tabview/browser_tabview_bug651311.js

@@ -0,0 +1,38 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+function test() {
+  waitForExplicitFinish();
+
+  let callCount = 0;
+
+  newWindow(function (win) {
+    registerCleanupFunction(function () win.close());
+
+    win.TabView._initFrame(function () {
+      is(callCount++, 0, "call count is zero");
+      ok(win.TabView.getContentWindow().UI, "content window is loaded");
+    });
+
+    win.TabView._initFrame(function () {
+      is(callCount++, 1, "call count is one");
+      ok(win.TabView.getContentWindow().UI, "content window is loaded");
+    });
+
+    win.TabView._initFrame(function () {
+      is(callCount, 2, "call count is two");
+      ok(win.TabView.getContentWindow().UI, "content window is loaded");
+      finish();
+    });
+  });
+}
+
+function newWindow(callback) {
+  let opts = "chrome,all,dialog=no,height=800,width=800";
+  let win = window.openDialog(getBrowserURL(), "_blank", opts);
+
+  win.addEventListener("load", function onLoad() {
+    win.removeEventListener("load", onLoad, false);
+    callback(win);
+  }, false);
+}