Added a test that currently is able to print to pdf.

chrome/browser/printing/print_preview_pdf_generated_browsertest.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 <string>
+#include <vector>
+
+#include "base/files/file_path.h"
+#include "base/logging.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/path_service.h"
+#include "base/run_loop.h"
+#include "base/strings/string_util.h"
+#include "chrome/app/chrome_command_ids.h"
+#include "chrome/browser/net/referrer.h"
+#include "chrome/browser/printing/print_preview_dialog_controller.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/ui/browser.h"
+#include "chrome/browser/ui/browser_commands.h"
+#include "chrome/browser/ui/tabs/tab_strip_model.h"
+#include "chrome/browser/ui/webui/print_preview/print_preview_handler.h"
+#include "chrome/browser/ui/webui/print_preview/print_preview_ui.h"
+#include "chrome/browser/ui/webui/print_preview/sticky_settings.h"
+#include "chrome/common/chrome_paths.h"
+#include "chrome/common/print_messages.h"
+#include "chrome/common/url_constants.h"
+#include "chrome/test/base/in_process_browser_test.h"
+#include "chrome/test/base/ui_test_utils.h"
+#include "content/public/browser/web_contents.h"
+#include "content/public/browser/web_ui_message_handler.h"
+#include "content/public/common/page_transition_types.h"
+#include "content/public/test/browser_test_utils.h"
+#include "content/public/test/test_navigation_observer.h"
+#include "content/public/test/test_utils.h"
+#include "ui/events/keycodes/keyboard_codes.h"
+#include "url/gurl.h"
+#include "ipc/ipc_message_macros.h"
+
+using content::WebContents;
+using content::WebContentsObserver;
+
+class PrintPreviewObserver;
+class UIDoneLoadingMessageHandler;
+
+// Need to split declarations & definitions due to forward declaration problem

[Lei Zhang, 2014/06/17 21:57:32]

You don't need to state this. It's fine to split the decl and definition.

[ivandavid, 2014/06/17 22:59:15]

I removed the comment.

+
+// Message refers to the 'UILoaded' message from print_preview.js.
+// It gets sent either from onPreviewGenerationDone or from
+// onManipulateSettings_() in print_preview.js
+enum state {

[Lei Zhang, 2014/06/17 21:57:32]

style: State,
http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml?showone=Enumer...

[ivandavid, 2014/06/17 22:59:16]

Made the enums look like constants rather than macros.

[Lei Zhang, 2014/06/17 23:22:20]

Oh, the previous MACRO_NAME style is actually preferred in Chromium.

+  // Waiting for the first message so the program can select Save as PDF
+  WAITING_TO_SEND_SAVE_AS_PDF = 0,
+  // Waiting for the second message so the test can set the layout
+  WAITING_TO_SEND_LAYOUT_SETTINGS = 1,
+  // Waiting for the third message so the test can set the page numbers
+  WAITING_TO_SEND_PAGE_NUMBERS = 2,
+  // Waiting for the forth message so the test can set the headers checkbox
+  WAITING_TO_SEND_HEADERS_AND_FOOTERS = 3,
+  // Waiting for the fifth message so the test can set the background checkbox
+  WAITING_TO_SEND_BACKGROUND_COLORS_AND_IMAGES = 4,
+  // Waiting for the sixth message so the test can set the margins combobox
+  WAITING_TO_SEND_MARGINS = 5,
+  // Waiting for the final message so the program can save to PDF.
+  WAITING_FOR_FINAL_MESSAGE = 6
+};
+
+class PrintPreviewObserver : public WebContentsObserver {
+  public:
+    explicit PrintPreviewObserver(WebContents* dialog, Browser* browser);
+    virtual ~PrintPreviewObserver();
+
+    void set_quit_closure(const base::Closure &closure);
+    void EndLoop();
+    bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
+    PrintPreviewUI* GetUI() {
+      return ui_;
+    }
+
+    WebContents* GetPreviewContents() {
+      return web_contents_;
+    }
+
+    // Calls a javascript function that will change the print preview settings,
+    // such as the layout, the margins, page numbers, etc.
+    void ManipulatePreviewSettings(enum state);

[Lei Zhang, 2014/06/17 21:57:33]

enum state -> State state

[ivandavid, 2014/06/17 22:59:15]

Changed everywhere.

[Lei Zhang, 2014/06/17 23:22:20]

You didn't actually change this one. You still have "enum State" in places where
you can just write "State".

+
+    // Function to set the print preview settings and save them so they
+    // can be sent later. Currently only used in the constructor. Will be
+    // used when creating a test and take command line arguments.
+
+    // For margins, 0 is default, 1 is none, 2 is minimum, and 3 is

[Lei Zhang, 2014/06/17 21:57:32]

There's an enum MarginType in printing/print_job_constants.h. Use that rather
than invent your own.

[ivandavid, 2014/06/17 22:59:16]

Change the type to printing::MarginType.

+    // custom. Don't use custom.
+    void SetPrintPreviewSettings(std::string layout_settings = "",

[Lei Zhang, 2014/06/17 21:57:33]

No default arguments please.
http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml?showone=Defaul...

[ivandavid, 2014/06/17 22:59:15]

I removed them.

+                                 std::string page_numbers = "",
+                                 bool headers_and_footers = true,
+                                 bool background_colors_and_images = false,
+                                 int margins = 0);
+
+  private:
+    void OnDidGetPreviewPageCount(
+        const PrintHostMsg_DidGetPreviewPageCount_Params &params);
+
+    void DidCloneToNewWebContents(WebContents* old_web_contents,
+                                  WebContents* new_web_contents)
+                                  OVERRIDE;
+
+    void WebContentsDestroyed();
+
+    Browser* browser_;
+    base::Closure closure_;
+    WebContents* web_contents_;
+
+    PrintPreviewUI* ui_;
+
+    int count_;
+
+    scoped_ptr<PrintPreviewObserver> print_preview_observer_;
+    scoped_ptr<base::StringValue> message_name_;
+    scoped_ptr<base::StringValue> layout_settings_;
+    scoped_ptr<base::StringValue> page_numbers_;
+    scoped_ptr<base::FundamentalValue> headers_and_footers_;
+    scoped_ptr<base::FundamentalValue> background_colors_and_images_;
+    scoped_ptr<base::FundamentalValue> margins_;
+

[ivandavid, 2014/06/17 21:38:18]

I save all the settings in the class, because I want to fill them out at the
beginning of the test, then later save. Therefore I need to save them ahead of
time.

+    DISALLOW_COPY_AND_ASSIGN(PrintPreviewObserver);
+};
+
+class UIDoneLoadingMessageHandler : public content::WebUIMessageHandler {
+  public:
+    explicit UIDoneLoadingMessageHandler(PrintPreviewObserver* observer);
+    virtual ~UIDoneLoadingMessageHandler();
+    void HandleDone(const base::ListValue* /* args */);
+    void RegisterMessages() OVERRIDE;
+  private:
+    PrintPreviewObserver* observer_;
+    state state_;
+
+  DISALLOW_COPY_AND_ASSIGN(UIDoneLoadingMessageHandler);
+};
+
+UIDoneLoadingMessageHandler::UIDoneLoadingMessageHandler(
+    PrintPreviewObserver* observer) :
+  observer_(observer), state_(WAITING_TO_SEND_SAVE_AS_PDF) {}
+
+UIDoneLoadingMessageHandler::~UIDoneLoadingMessageHandler() {
+  observer_ = NULL;
+}
+
+void UIDoneLoadingMessageHandler::RegisterMessages() OVERRIDE {
+  web_ui()->RegisterMessageCallback(
+  "UILoaded",
+  base::Bind(&UIDoneLoadingMessageHandler::HandleDone,
+             base::Unretained(this)));
+}
+
+void UIDoneLoadingMessageHandler::HandleDone(
+    const base::ListValue* /* args */) {
+  if (state_ == WAITING_FOR_FINAL_MESSAGE) {
+    observer_->EndLoop();
+  } else {
+    observer_->ManipulatePreviewSettings(state_);
+    state_ = static_cast<enum state>(static_cast<int>(state_) + 1);

[ivandavid, 2014/06/17 21:38:18]

I wasn't sure if there was a cleaner way to do this, since I couldn't use the ++
operator on the enum.

+  }
+}
+
+PrintPreviewObserver::PrintPreviewObserver(
+    WebContents* dialog,
+    Browser* browser) :
+    WebContentsObserver(dialog), browser_(browser), count_(0) {
+  SetPrintPreviewSettings("LANDSCAPE", "", false, false, 2);
+}

[ivandavid, 2014/06/17 21:38:18]

I change most of the settings to show that it will work.

+
+PrintPreviewObserver::~PrintPreviewObserver() {
+  browser_ = NULL;
+  message_name_.reset();
+  layout_settings_.reset();
+  page_numbers_.reset();
+  headers_and_footers_.reset();
+  background_colors_and_images_.reset();
+  margins_.reset();
+}
+
+void PrintPreviewObserver::set_quit_closure(const base::Closure &closure) {
+  closure_ = closure;
+}
+
+void PrintPreviewObserver::EndLoop() {
+  base::MessageLoop::current()->PostTask(FROM_HERE, closure_);
+}
+
+bool PrintPreviewObserver::OnMessageReceived(const IPC::Message& message)
+    OVERRIDE {
+  IPC_BEGIN_MESSAGE_MAP(PrintPreviewObserver, message)
+    IPC_MESSAGE_HANDLER(PrintHostMsg_DidGetPreviewPageCount,
+                        OnDidGetPreviewPageCount)
+    IPC_MESSAGE_UNHANDLED(break;)
+  IPC_END_MESSAGE_MAP();
+  return false;
+}
+
+void PrintPreviewObserver::OnDidGetPreviewPageCount(
+    const PrintHostMsg_DidGetPreviewPageCount_Params &params) {
+
+  WebContents* tab = browser_->tab_strip_model()->GetActiveWebContents();
+
+  ASSERT_TRUE(tab);
+
+  printing::PrintPreviewDialogController* dialog_controller =
+      printing::PrintPreviewDialogController::GetInstance();
+
+  ASSERT_TRUE(dialog_controller);
+
+  web_contents_ = dialog_controller->GetPrintPreviewForContents(tab);
+
+  ASSERT_TRUE(web_contents_ && printing::PrintPreviewDialogController::
+      IsPrintPreviewDialog(web_contents_));
+
+  ui_ = static_cast<PrintPreviewUI*>(web_contents_->GetWebUI()->
+      GetController());
+
+  ASSERT_TRUE(ui_);
+
+  ASSERT_TRUE(ui_->web_ui());
+
+  this->Observe(web_contents_);
+
+  UIDoneLoadingMessageHandler* handler = new UIDoneLoadingMessageHandler(this);
+
+  ui_->web_ui()->AddMessageHandler(handler);
+}
+
+void PrintPreviewObserver::

[Lei Zhang, 2014/06/17 21:57:32]

style:

void PrintPreviewObserver::SetPrintPreviewSettings(
  std::string ...) {

http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml?showone=Functi...

+    SetPrintPreviewSettings(std::string layout_settings,

[Lei Zhang, 2014/06/17 21:57:33]

non-POD types should be passed by const reference, not by value.

[ivandavid, 2014/06/17 22:59:16]

I think I fixed it.

+                            std::string page_numbers,
+                            bool headers_and_footers,
+                            bool background_colors_and_images,
+                            int margins) {
+ layout_settings_.reset(new base::StringValue(layout_settings));

[Lei Zhang, 2014/06/17 21:57:33]

style: indentation

+ page_numbers_.reset(new base::StringValue(page_numbers));
+ headers_and_footers_.reset(
+     new base::FundamentalValue(headers_and_footers));
+ background_colors_and_images_.reset(
+     new base::FundamentalValue(background_colors_and_images));
+ margins_.reset(new base::FundamentalValue(margins));
+}
+
+
+void PrintPreviewObserver::ManipulatePreviewSettings(enum state state) {
+  std::vector<const base::Value*> args;
+  if (state == WAITING_TO_SEND_SAVE_AS_PDF) {
+    message_name_.reset(new base::StringValue("SAVE_AS_PDF"));
+    args.push_back(message_name_.get());
+    ui_->web_ui()->CallJavascriptFunction("onManipulateSettings", args);

[Lei Zhang, 2014/06/17 21:57:32]

Since you are doing the same thing at the end of each one of these blocks, how
about move it to the bottom?

[ivandavid, 2014/06/17 22:59:16]

Done.

+  } else if (state == WAITING_TO_SEND_LAYOUT_SETTINGS) {
+    message_name_.reset(new base::StringValue("LAYOUT_SETTINGS"));
+    args.push_back(message_name_.get());
+    args.push_back(layout_settings_.get());
+    ui_->web_ui()->CallJavascriptFunction("onManipulateSettings", args);
+  } else if (state == WAITING_TO_SEND_PAGE_NUMBERS) {
+    message_name_.reset(new base::StringValue("PAGE_NUMBERS"));
+    args.push_back(message_name_.get());
+    args.push_back(page_numbers_.get());
+    ui_->web_ui()->CallJavascriptFunction("onManipulateSettings", args);
+  } else if (state == WAITING_TO_SEND_HEADERS_AND_FOOTERS) {
+    message_name_.reset(new base::StringValue("HEADERS_AND_FOOTERS"));
+    args.push_back(message_name_.get());
+    args.push_back(headers_and_footers_.get());
+    ui_->web_ui()->CallJavascriptFunction("onManipulateSettings", args);
+  } else if (state == WAITING_TO_SEND_BACKGROUND_COLORS_AND_IMAGES) {
+    message_name_.reset(new base::StringValue("BACKGROUND_COLORS_AND_IMAGES"));
+    args.push_back(message_name_.get());
+    args.push_back(background_colors_and_images_.get());
+    ui_->web_ui()->CallJavascriptFunction("onManipulateSettings", args);
+  } else if (state == WAITING_TO_SEND_MARGINS) {
+    message_name_.reset(new base::StringValue("MARGINS"));
+    args.push_back(message_name_.get());
+    args.push_back(margins_.get());
+    ui_->web_ui()->CallJavascriptFunction("onManipulateSettings", args);
+  }
+}
+
+void PrintPreviewObserver::DidCloneToNewWebContents(
+    WebContents* old_web_contents,
+    WebContents* new_web_contents)
+    OVERRIDE {
+  this->Observe(new_web_contents);
+}
+
+void PrintPreviewObserver::WebContentsDestroyed() {
+  this->EndLoop();
+}
+
+class PrintPreviewPdfGeneratedBrowserTest : public InProcessBrowserTest {
+  public:
+    PrintPreviewPdfGeneratedBrowserTest() {}
+    virtual ~PrintPreviewPdfGeneratedBrowserTest() {}
+
+    void NavigateAndPreview(std::string file_name) {
+      base::FilePath directory("printing");
+      base::FilePath file(file_name);
+
+      ui_test_utils::NavigateToURL(browser(),
+                                   ui_test_utils::GetTestUrl(directory, file));
+
+      base::RunLoop loop;
+      print_preview_observer_->set_quit_closure(loop.QuitClosure());
+      chrome::Print(browser());
+      loop.Run();
+    }
+
+    void Print() {
+      base::FilePath pdf_file_save_path;

[ivandavid, 2014/06/17 21:38:18]

Changed the variable to your suggestion.

+      ASSERT_TRUE(PathService::Get(chrome::DIR_TEST_DATA, &pdf_file_save_path));
+      pdf_file_save_path = pdf_file_save_path.AppendASCII("printing");
+      pdf_file_save_path = pdf_file_save_path.AppendASCII("dummy.pdf");
+
+      base::RunLoop loop;
+      print_preview_observer_->set_quit_closure(loop.QuitClosure());
+
+      print_preview_observer_->GetUI()->handler_->
+          FileSelected(pdf_file_save_path, 0, NULL);
+
+      loop.Run();
+    }
+
+  private:
+    virtual void SetUpOnMainThread() OVERRIDE {
+      WebContents* tab =
+          browser()->tab_strip_model()->GetActiveWebContents();
+      ASSERT_TRUE(tab);
+
+      print_preview_observer_.reset(new PrintPreviewObserver(tab, browser()));
+      chrome::DuplicateTab(browser());
+
+      WebContents* initiator_ =
+          browser()->tab_strip_model()->GetActiveWebContents();
+      ASSERT_TRUE(initiator_);
+      ASSERT_NE(tab, initiator_);
+    }
+
+    virtual void CleanUpOnMainThread() OVERRIDE {
+      print_preview_observer_.reset();
+    }
+
+    scoped_ptr<PrintPreviewObserver> print_preview_observer_;
+
+    DISALLOW_COPY_AND_ASSIGN(PrintPreviewPdfGeneratedBrowserTest);
+};
+
+IN_PROC_BROWSER_TEST_F(PrintPreviewPdfGeneratedBrowserTest, DummyTest) {
+    NavigateAndPreview("test2.html");
+    Print();
+}