Bug 1787979 - keyboard shortcut navigates to the wrong tab from Firefox View tab r=dao

* Remove index: 0 in FirefoxViewHandler.openTab
* Add condition in tabbrowser _selectNextTab for FirefoxView tab
* Fix tests

Differential Revision: https://phabricator.services.mozilla.com/D156688

browser/base/content/browser.js

@@ -9934,7 +9934,7 @@ var FirefoxViewHandler = {
       );
     }
     if (!this.tab) {
-      this.tab = gBrowser.addTrustedTab("about:firefoxview", { index: 0 });
+      this.tab = gBrowser.addTrustedTab("about:firefoxview");
       this.tab.addEventListener("TabClose", this, { once: true });
       gBrowser.tabContainer.addEventListener("TabSelect", this);
       window.addEventListener("activate", this);

browser/base/content/test/general/browser_visibleTabs.js

@@ -14,11 +14,14 @@ add_task(async function() {
 
   let testTab = BrowserTestUtils.addTab(gBrowser);
 
+  let firefoxViewTab = BrowserTestUtils.addTab(gBrowser, "about:firefoxview");
+  gBrowser.hideTab(firefoxViewTab);
+
   let visible = gBrowser.visibleTabs;
-  is(visible.length, 3, "3 tabs should be open");
+  is(visible.length, 3, "3 tabs should be visible");
   is(visible[0], pinned, "the pinned tab is first");
   is(visible[1], origTab, "original tab is next");
-  is(visible[2], testTab, "last created tab is last");
+  is(visible[2], testTab, "last created tab is next to last");
 
   // Only show the test tab (but also get pinned and selected)
   is(
@@ -37,7 +40,7 @@ add_task(async function() {
   is(visible.length, 2, "2 tabs should be visible including the pinned");
   is(visible[0], pinned, "first is pinned");
   is(visible[1], testTab, "next is the test tab");
-  is(gBrowser.tabs.length, 3, "3 tabs should still be open");
+  is(gBrowser.tabs.length, 4, "4 tabs should still be open");
 
   gBrowser.selectTabAtIndex(1);
   is(gBrowser.selectedTab, testTab, "second tab is the test tab");
@@ -72,8 +75,22 @@ add_task(async function() {
   gBrowser.tabContainer.advanceSelectedTab(-1, true);
   is(gBrowser.selectedTab, testTab, "next to test tab again");
 
-  // Try showing all tabs
-  gBrowser.showOnlyTheseTabs(Array.from(gBrowser.tabs));
+  // select a hidden tab thats selectable
+  gBrowser.selectedTab = firefoxViewTab;
+  gBrowser.tabContainer.advanceSelectedTab(1, true);
+  is(gBrowser.selectedTab, pinned, "next to first visible tab, the pinned tab");
+  gBrowser.tabContainer.advanceSelectedTab(1, true);
+  is(gBrowser.selectedTab, testTab, "next to second visible tab, the test tab");
+
+  // again select a hidden tab thats selectable
+  gBrowser.selectedTab = firefoxViewTab;
+  gBrowser.tabContainer.advanceSelectedTab(-1, true);
+  is(gBrowser.selectedTab, testTab, "next to last visible tab, the test tab");
+  gBrowser.tabContainer.advanceSelectedTab(-1, true);
+  is(gBrowser.selectedTab, pinned, "next to first visible tab, the pinned tab");
+
+  // Try showing all tabs except for the Firefox View tab
+  gBrowser.showOnlyTheseTabs(Array.from(gBrowser.tabs.slice(0, 3)));
   is(gBrowser.visibleTabs.length, 3, "all 3 tabs are visible again");
 
   // Select the pinned tab and show the testTab to make sure selection updates
@@ -94,7 +111,10 @@ add_task(async function() {
   visible = gBrowser.visibleTabs;
   is(visible.length, 1, "only the original tab is visible");
   is(visible[0], testTab, "it's the original tab");
-  is(gBrowser.tabs.length, 2, "still have 2 open tabs");
+  is(gBrowser.tabs.length, 3, "still have 3 open tabs");
+
+  // Close the selectable hidden tab
+  gBrowser.removeTab(firefoxViewTab);
 
   // Close the last visible tab and make sure we still get a visible tab
   gBrowser.removeTab(testTab);

browser/components/firefoxview/tests/browser/browser_firefoxview_tab.js

@@ -64,9 +64,8 @@ add_task(async function number_tab_select_shortcut() {
     AppConstants.MOZ_WIDGET_GTK ? { altKey: true } : { accelKey: true },
     win
   );
-  is(
-    win.gBrowser.tabContainer.selectedIndex,
-    1,
+  ok(
+    !win.FirefoxViewHandler.tab.selected,
     "Number shortcut to select the first tab skipped the Firefox View tab"
   );
   await BrowserTestUtils.closeWindow(win);

browser/components/firefoxview/tests/browser/head.js

@@ -151,11 +151,6 @@ async function waitForVisibleSetupStep(browser, expected) {
 function assertFirefoxViewTab(w) {
   ok(w.FirefoxViewHandler.tab, "Firefox View tab exists");
   ok(w.FirefoxViewHandler.tab?.hidden, "Firefox View tab is hidden");
-  is(
-    w.gBrowser.tabs.indexOf(w.FirefoxViewHandler.tab),
-    0,
-    "Firefox View tab is the first tab"
-  );
   is(
     w.gBrowser.visibleTabs.indexOf(w.FirefoxViewHandler.tab),
     -1,
@@ -175,7 +170,7 @@ async function openFirefoxViewTab(w) {
     w
   );
   assertFirefoxViewTab(w);
-  is(w.gBrowser.tabContainer.selectedIndex, 0, "Firefox View tab is selected");
+  ok(w.FirefoxViewHandler.tab.selected, "Firefox View tab is selected");
   await BrowserTestUtils.browserLoaded(w.FirefoxViewHandler.tab.linkedBrowser);
   return w.FirefoxViewHandler.tab;
 }

browser/components/newtab/test/browser/head.js

@@ -384,17 +384,12 @@ function test_newtab(testInfo, browserURL = "about:newtab") {
 async function assertFirefoxViewTabSelected(w) {
   ok(w.FirefoxViewHandler.tab, "Firefox View tab exists");
   ok(w.FirefoxViewHandler.tab?.hidden, "Firefox View tab is hidden");
-  is(
-    w.gBrowser.tabs.indexOf(w.FirefoxViewHandler.tab),
-    0,
-    "Firefox View tab is the first tab"
-  );
   is(
     w.gBrowser.visibleTabs.indexOf(w.FirefoxViewHandler.tab),
     -1,
     "Firefox View tab is not in the list of visible tabs"
   );
-  is(w.gBrowser.tabContainer.selectedIndex, 0, "Firefox View tab is selected");
+  ok(w.FirefoxViewHandler.tab.selected, "Firefox View tab is selected");
   await BrowserTestUtils.browserLoaded(w.FirefoxViewHandler.tab.linkedBrowser);
 }
 

browser/components/sessionstore/test/browser_firefoxView_restore.js

@@ -18,8 +18,8 @@ add_task(async function test_TODO() {
 
   is(
     state.windows[0].selected,
-    1,
-    "The selected tab is Firefox view tab which is the first tab"
+    3,
+    "The selected tab is Firefox view tab which is the third tab"
   );
 
   gBrowser.selectedTab = tab;
@@ -28,7 +28,7 @@ add_task(async function test_TODO() {
 
   // The FxView tab doesn't get recorded in the session state and when we restore we want
   // to open the tab that was previously opened so we record the tab position minus one
-  is(state.windows[0].selected, 2, "The selected tab is the second tab");
+  is(state.windows[0].selected, 1, "The selected tab is the first tab");
 
   gBrowser.removeTab(window.FirefoxViewHandler.tab);
   gBrowser.removeTab(gBrowser.selectedTab);

toolkit/components/messaging-system/schemas/SpecialMessageActionSchemas/test/browser/browser_sma_click_element.js

@@ -112,7 +112,7 @@ async function openFirefoxViewTab(w) {
     w
   );
   assertFirefoxViewTab(w);
-  is(w.gBrowser.tabContainer.selectedIndex, 0, "Firefox View tab is selected");
+  ok(w.FirefoxViewHandler.tab.selected, "Firefox View tab is selected");
   await BrowserTestUtils.browserLoaded(w.FirefoxViewHandler.tab.linkedBrowser);
   return w.FirefoxViewHandler.tab;
 }
@@ -120,11 +120,6 @@ async function openFirefoxViewTab(w) {
 function assertFirefoxViewTab(w) {
   ok(w.FirefoxViewHandler.tab, "Firefox View tab exists");
   ok(w.FirefoxViewHandler.tab?.hidden, "Firefox View tab is hidden");
-  is(
-    w.gBrowser.tabs.indexOf(w.FirefoxViewHandler.tab),
-    0,
-    "Firefox View tab is the first tab"
-  );
   is(
     w.gBrowser.visibleTabs.indexOf(w.FirefoxViewHandler.tab),
     -1,

toolkit/components/messaging-system/schemas/SpecialMessageActionSchemas/test/browser/browser_sma_open_firefox_view.js

@@ -34,11 +34,6 @@ add_setup(async () => {
 function assertFirefoxViewTab(w = window) {
   ok(w.FirefoxViewHandler.tab, "Firefox View tab exists");
   ok(w.FirefoxViewHandler.tab?.hidden, "Firefox View tab is hidden");
-  is(
-    w.gBrowser.tabs.indexOf(w.FirefoxViewHandler.tab),
-    0,
-    "Firefox View tab is the first tab"
-  );
   is(
     w.gBrowser.visibleTabs.indexOf(w.FirefoxViewHandler.tab),
     -1,

toolkit/content/widgets/tabbox.js

@@ -758,10 +758,23 @@
 
     advanceSelectedTab(aDir, aWrap) {
       let startTab = this.ariaFocusedItem || this.selectedItem;
-      let newTab = this.findNextTab(startTab, {
-        direction: aDir,
-        wrap: aWrap,
-      });
+      let newTab = null;
+
+      // Handle keyboard navigation for a hidden tab that can be selected, like the Firefox View tab,
+      // which has a random placement in this.allTabs.
+      if (startTab.hidden) {
+        if (aDir == 1) {
+          newTab = this.allTabs.find(tab => !tab.hidden);
+        } else {
+          newTab = this.allTabs.findLast(tab => !tab.hidden);
+        }
+      } else {
+        newTab = this.findNextTab(startTab, {
+          direction: aDir,
+          wrap: aWrap,
+        });
+      }
+
       if (newTab && newTab != startTab) {
         this._selectNewTab(newTab, aDir, aWrap);
       }