Fix Print Preview Alt + Left Arrow breakage

chrome/browser/printing/print_preview_dialog_controller_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/printing/print_preview_dialog_controller.h"
 
 #include <memory>
 
 #include "chrome/browser/printing/print_preview_test.h"
 #include "chrome/browser/printing/print_view_manager.h"
 #include "chrome/browser/ui/browser_commands.h"
 #include "chrome/browser/ui/browser_finder.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/browser/ui/webui/print_preview/print_preview_ui.h"
+#include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/navigation_details.h"
+#include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/web_contents_delegate.h"
+#include "content/public/browser/web_contents_observer.h"
 #include "content/public/common/url_constants.h"
 #include "content/public/test/web_contents_tester.h"
 
 using content::WebContents;
+using content::WebContentsObserver;
 
 namespace {
 // content::WebContentsDelegate destructor is protected: subclass for testing.
 class TestWebContentsDelegate : public content::WebContentsDelegate {};
+
+class PrintPreviewDialogDestroyedObserver : public WebContentsObserver {
+ public:
+  explicit PrintPreviewDialogDestroyedObserver(WebContents* dialog)
+      : WebContentsObserver(dialog),
+        dialog_destroyed_(false) {
+  }
+  ~PrintPreviewDialogDestroyedObserver() override {}
+
+  bool dialog_destroyed() const { return dialog_destroyed_; }
+
+ private:
+  // content::WebContentsObserver implementation.
+  void WebContentsDestroyed() override { dialog_destroyed_ = true; }
+
+  bool dialog_destroyed_;
+
+  DISALLOW_COPY_AND_ASSIGN(PrintPreviewDialogDestroyedObserver);
+};
+
+class PrintPreviewDialogControllerForTest :
+    public printing::PrintPreviewDialogController {
+ public:
+  PrintPreviewDialogControllerForTest() {
+    next_dialog_ = 1;

[Lei Zhang, 2016/08/17 21:27:55]

Use the initializer list

+  }
+
+  WebContents* GetOrCreatePreviewDialog(WebContents * initiator) override {
+    DCHECK(initiator);
+
+    // Get the print preview dialog for |initiator|.
+    WebContents* preview_dialog = GetPrintPreviewForContents(initiator);
+    if (!preview_dialog) {

[Lei Zhang, 2016/08/17 21:27:55]

I usually like to write:

if (foo) {
 DoFoo();
} else {
 DoBar();
}

rather than if (!foo) ...

+      // Create a fake dialog and put it in the map, then observe initiator
+      preview_dialog = reinterpret_cast<WebContents*>(next_dialog_++);
+      preview_dialog_map_[preview_dialog] = initiator;
+      AddObservers(initiator);
+    } else {
+      // Show the initiator holding the existing preview dialog.
+      initiator->GetDelegate()->ActivateContents(initiator);
+    }
+    return preview_dialog;
+  }
+
+ private:
+  ~PrintPreviewDialogControllerForTest() override {}
+
+  // Override so that the controller doesn't try to close a fake web contents.
+  void RemoveInitiator(WebContents* initiator) override {
+    WebContents* preview_dialog = GetPrintPreviewForContents(initiator);
+    DCHECK(preview_dialog);
+    preview_dialog_map_[preview_dialog] = nullptr;
+    RemoveObservers(initiator);
+    printing::PrintViewManager::FromWebContents(initiator)->PrintPreviewDone();
+  }
+
+  DISALLOW_COPY_AND_ASSIGN(PrintPreviewDialogControllerForTest);
+  int next_dialog_;
+};
+
+
+
 }  // namespace
 
 namespace printing {
 
 using PrintPreviewDialogControllerUnitTest = PrintPreviewTest;
 
 // Create/Get a preview dialog for initiator.
 TEST_F(PrintPreviewDialogControllerUnitTest, GetOrCreatePreviewDialog) {
   // Lets start with one window with one tab.
   EXPECT_EQ(1u, chrome::GetTotalBrowserCount());
@@ skipping 127 matching lines @@
   WebContents* new_preview_dialog =
       dialog_controller->GetOrCreatePreviewDialog(initiator);
 
   // New print preview dialog is a constrained window, so the number of tabs is
   // still 1.
   EXPECT_EQ(1, browser()->tab_strip_model()->count());
   // Verify a new print preview dialog has been created.
   EXPECT_NE(new_preview_dialog, preview_dialog);
 }
 
+// Test that print preview dialogs close on navigation to new pages
+// and when navigating to old pages via fwd/back, but that auto navigation
+// (typed + address bar) to an existing page as occurs in gmail does not cause
+// the dialogs to close.
+TEST_F(PrintPreviewDialogControllerUnitTest, CloseDialogOnNavigation) {

[Lei Zhang, 2016/08/17 21:27:55]

I prefer this version mainly because we don't have to modify the controller.

+  // Two similar URLs (same webpage, different URL fragments)
+  GURL tiger_barb("https://www.google.com/#q=tiger+barb");
+  GURL tiger("https://www.google.com/#q=tiger");
+
+  // Set up by opening a new tab and getting web contents
+  EXPECT_EQ(1u, chrome::GetTotalBrowserCount());
+  EXPECT_EQ(0, browser()->tab_strip_model()->count());
+  chrome::NewTab(browser());
+  EXPECT_EQ(1, browser()->tab_strip_model()->count());
+  WebContents* web_contents =
+      browser()->tab_strip_model()->GetActiveWebContents();
+  ASSERT_TRUE(web_contents);
+  content::NavigationController& nav_controller = web_contents->GetController();
+
+  // Navigate to first page
+  nav_controller.LoadURL(tiger, content::Referrer(),
+                         ui::PageTransitionFromInt(ui::PAGE_TRANSITION_LINK),
+                         std::string());
+  CommitPendingLoad(&nav_controller);
+  EXPECT_EQ(tiger, web_contents->GetLastCommittedURL());
+
+  // Get the preview dialog
+  PrintPreviewDialogController* dialog_controller =
+      PrintPreviewDialogController::GetInstance();
+  ASSERT_TRUE(dialog_controller);
+  WebContents* tiger_preview_dialog =
+      dialog_controller->GetOrCreatePreviewDialog(web_contents);
+  PrintViewManager* manager = PrintViewManager::FromWebContents(web_contents);
+  manager->PrintPreviewNow(false);
+
+  // New print preview dialog is a constrained window, so the number of tabs is
+  // still 1.
+  EXPECT_EQ(1, browser()->tab_strip_model()->count());
+  EXPECT_NE(web_contents, tiger_preview_dialog);
+  PrintPreviewDialogDestroyedObserver tiger_destroyed(tiger_preview_dialog);
+
+  // Navigate via link to a similar page.
+  nav_controller.LoadURL(tiger_barb, content::Referrer(),
+                         ui::PageTransitionFromInt(ui::PAGE_TRANSITION_LINK),
+                         std::string());
+  CommitPendingLoad(&nav_controller);
+
+  // Check navigation was successful
+  EXPECT_EQ(tiger_barb, web_contents->GetLastCommittedURL());
+
+  // Print preview now should return true as the navigation should have closed
+  // |tiger_preview_dialog| and the previous dialog should have closed.
+  EXPECT_TRUE(manager->PrintPreviewNow(false));
+  WebContents* tiger_barb_preview_dialog =
+      dialog_controller->GetOrCreatePreviewDialog(web_contents);
+  ASSERT_TRUE(tiger_barb_preview_dialog);
+
+  // Check a new dialog was created - either the pointers should be different or
+  // the previous web contents must have been destroyed.
+  EXPECT_TRUE(tiger_destroyed.dialog_destroyed() ||
+              tiger_barb_preview_dialog != tiger_preview_dialog);
+  EXPECT_NE(tiger_barb_preview_dialog, web_contents);
+  PrintPreviewDialogDestroyedObserver tiger_barb_destroyed(
+      tiger_barb_preview_dialog);
+
+  // Now this returns false as |tiger_barb_preview_dialog| is open.
+  EXPECT_FALSE(manager->PrintPreviewNow(false));
+
+  // Navigate with back button or ALT+LEFT ARROW to a similar page.
+  nav_controller.GoBack();
+  CommitPendingLoad(&nav_controller);
+  EXPECT_EQ(tiger, web_contents->GetLastCommittedURL());
+  EXPECT_TRUE(manager->PrintPreviewNow(false));
+
+  // Get new dialog
+  WebContents* tiger_preview_dialog_2 =
+      dialog_controller->GetOrCreatePreviewDialog(web_contents);
+  ASSERT_TRUE(tiger_preview_dialog_2);
+
+  // Verify this is a new dialog.
+  EXPECT_TRUE(tiger_barb_destroyed.dialog_destroyed() ||
+              tiger_barb_preview_dialog != tiger_preview_dialog_2);
+  EXPECT_NE(tiger_preview_dialog_2, web_contents);
+  PrintPreviewDialogDestroyedObserver tiger_2_destroyed(
+      tiger_preview_dialog_2);
+
+  // Try to simulate Gmail navigation: Navigate to an existing page (via
+  // Forward) but modify the navigation type while pending to look like an
+  // address bar + typed transition (like Gmail auto navigation)
+  nav_controller.GoForward();
+  nav_controller.GetPendingEntry()->SetTransitionType(ui::PageTransitionFromInt(
+      ui::PAGE_TRANSITION_TYPED | ui::PAGE_TRANSITION_FROM_ADDRESS_BAR));
+  CommitPendingLoad(&nav_controller);
+
+  // Navigation successful
+  EXPECT_EQ(tiger_barb, web_contents->GetLastCommittedURL());
+
+  // Print preview should not have changed due to this navigation type so print
+  // preview now should return false, dialog is still alive, and the dialog
+  // returned by GetOrCreatePreviewDialog should be the same as the earlier
+  // dialog.
+  EXPECT_FALSE(manager->PrintPreviewNow(false));
+  EXPECT_FALSE(tiger_2_destroyed.dialog_destroyed());
+  WebContents* tiger_preview_dialog_2b =
+      dialog_controller->GetOrCreatePreviewDialog(web_contents);
+  ASSERT_TRUE(tiger_preview_dialog_2b);
+  EXPECT_EQ(tiger_preview_dialog_2b, tiger_preview_dialog_2);
+  EXPECT_NE(tiger_preview_dialog_2b, web_contents);
+}
+
+// Test that print preview dialogs close on navigation to new pages
+// and when navigating to old pages via fwd/back, but that auto navigation
+// (typed + address bar) to an existing page as occurs in gmail does not cause
+// the dialogs to close.
+TEST_F(PrintPreviewDialogControllerUnitTest, CloseDialogOnNavigationV2) {
+  // Two similar URLs (same webpage, different URL fragments)
+  GURL tiger_barb("https://www.google.com/#q=tiger+barb");
+  GURL tiger("https://www.google.com/#q=tiger");
+
+  // Set up by opening a new tab and getting web contents
+  EXPECT_EQ(1u, chrome::GetTotalBrowserCount());
+  EXPECT_EQ(0, browser()->tab_strip_model()->count());
+  chrome::NewTab(browser());
+  EXPECT_EQ(1, browser()->tab_strip_model()->count());
+  WebContents* web_contents =
+      browser()->tab_strip_model()->GetActiveWebContents();
+  ASSERT_TRUE(web_contents);
+  content::NavigationController& nav_controller = web_contents->GetController();
+
+  // Navigate to first page
+  nav_controller.LoadURL(tiger, content::Referrer(),
+                         ui::PageTransitionFromInt(ui::PAGE_TRANSITION_LINK),
+                         std::string());
+  CommitPendingLoad(&nav_controller);
+  EXPECT_EQ(tiger, web_contents->GetLastCommittedURL());
+
+  // Get the preview dialog
+  PrintPreviewDialogControllerForTest* dialog_controller =
+      new PrintPreviewDialogControllerForTest;
+  ASSERT_TRUE(dialog_controller);
+  PrintViewManager* manager = PrintViewManager::FromWebContents(web_contents);
+  WebContents* tiger_preview_dialog =
+      dialog_controller->GetOrCreatePreviewDialog(web_contents);
+  manager->PrintPreviewNow(false);
+
+  // New print preview dialog is a constrained window, so the number of tabs is
+  // still 1.
+  EXPECT_EQ(1, browser()->tab_strip_model()->count());
+  EXPECT_NE(web_contents, tiger_preview_dialog);
+
+  // Navigate via link to a similar page.
+  nav_controller.LoadURL(tiger_barb, content::Referrer(),
+                         ui::PageTransitionFromInt(ui::PAGE_TRANSITION_LINK),
+                         std::string());
+  CommitPendingLoad(&nav_controller);
+
+  // Check navigation was successful
+  EXPECT_EQ(tiger_barb, web_contents->GetLastCommittedURL());
+
+  // Print preview now should return true as the navigation should have closed
+  // |tiger_preview_dialog|
+  EXPECT_TRUE(manager->PrintPreviewNow(false));
+  WebContents* tiger_barb_preview_dialog =
+      dialog_controller->GetOrCreatePreviewDialog(web_contents);
+  ASSERT_TRUE(tiger_barb_preview_dialog);
+
+  // Check a new dialog was created - pointers should be different.
+  EXPECT_TRUE(tiger_barb_preview_dialog != tiger_preview_dialog);
+  EXPECT_NE(tiger_barb_preview_dialog, web_contents);
+
+  // Now this returns false as |tiger_barb_preview_dialog| is open.
+  EXPECT_FALSE(manager->PrintPreviewNow(false));
+
+  // Navigate with back button or ALT+LEFT ARROW to a similar page.
+  nav_controller.GoBack();
+  CommitPendingLoad(&nav_controller);
+  EXPECT_EQ(tiger, web_contents->GetLastCommittedURL());
+  EXPECT_TRUE(manager->PrintPreviewNow(false));
+
+  // Get new dialog
+  WebContents* tiger_preview_dialog_2 =
+      dialog_controller->GetOrCreatePreviewDialog(web_contents);
+  ASSERT_TRUE(tiger_preview_dialog_2);
+
+  // Verify this is a new dialog.
+  EXPECT_TRUE(tiger_barb_preview_dialog != tiger_preview_dialog_2);
+  EXPECT_NE(tiger_preview_dialog_2, web_contents);
+
+  // Try to simulate Gmail navigation: Navigate to an existing page (via
+  // Forward) but modify the navigation type while pending to look like an
+  // address bar + typed transition (like Gmail auto navigation)
+  nav_controller.GoForward();
+  nav_controller.GetPendingEntry()->SetTransitionType(ui::PageTransitionFromInt(
+      ui::PAGE_TRANSITION_TYPED | ui::PAGE_TRANSITION_FROM_ADDRESS_BAR));
+  CommitPendingLoad(&nav_controller);
+
+  // Navigation successful
+  EXPECT_EQ(tiger_barb, web_contents->GetLastCommittedURL());
+
+  // Print preview should not have changed due to this navigation type so print
+  // preview now should return false, and the dialog returned by
+  // GetOrCreatePreviewDialog should be the same as the earlier dialog.
+  EXPECT_FALSE(manager->PrintPreviewNow(false));
+  WebContents* tiger_preview_dialog_2b =
+      dialog_controller->GetOrCreatePreviewDialog(web_contents);
+  ASSERT_TRUE(tiger_preview_dialog_2b);
+  EXPECT_EQ(tiger_preview_dialog_2b, tiger_preview_dialog_2);
+  EXPECT_NE(tiger_preview_dialog_2b, web_contents);
+}
 }  // namespace printing