🔐 Introduce DestinationFileSystem

DestinationFileSystem is the desktop implemenation of Destination, which
sends the data to the file system.

Bug: 785237
Change-Id: I034fab562eafde2240dc75743cb2ebbc6f7ec9ac
Reviewed-on: https://chromium-review.googlesource.com/776596
Commit-Queue: Christos Froussios <cfroussios@chromium.org>
Reviewed-by: Vaclav Brozek <vabr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#517442}

chrome/browser/ui/BUILD.gn

@@ -136,6 +136,8 @@ split_static_library("ui") {
     "page_info/page_info_ui.h",
     "passwords/account_avatar_fetcher.cc",
     "passwords/account_avatar_fetcher.h",
+    "passwords/destination_file_system.cc",
+    "passwords/destination_file_system.h",
     "passwords/manage_passwords_state.cc",
     "passwords/manage_passwords_state.h",
     "passwords/manage_passwords_view_utils.cc",

chrome/browser/ui/passwords/destination_file_system.cc

+// Copyright 2017 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/ui/passwords/destination_file_system.h"
+
+#include <utility>
+
+#include "base/files/file_util.h"
+
+DestinationFileSystem::DestinationFileSystem(base::FilePath destination_path)
+    : destination_path_(std::move(destination_path)) {}
+
+bool DestinationFileSystem::Write(const std::string& data) {
+  return base::WriteFile(destination_path_, data.c_str(), data.size());
+}

chrome/browser/ui/passwords/destination_file_system.h

+// Copyright 2017 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.
+
+#ifndef CHROME_BROWSER_UI_PASSWORDS_DESTINATION_FILE_SYSTEM_H_
+#define CHROME_BROWSER_UI_PASSWORDS_DESTINATION_FILE_SYSTEM_H_
+
+#include <string>
+
+#include "base/files/file_path.h"
+#include "base/macros.h"
+#include "components/password_manager/core/browser/export/destination.h"
+
+class DestinationFileSystem : public password_manager::Destination {
+ public:
+  explicit DestinationFileSystem(base::FilePath destination_path);
+  virtual ~DestinationFileSystem() = default;
+
+  // password_manager::Destination
+  bool Write(const std::string& data) override;
+
+ private:
+  // The file, to which the data will be written.
+  const base::FilePath destination_path_;
+
+  DISALLOW_COPY_AND_ASSIGN(DestinationFileSystem);
+};
+
+#endif  // CHROME_BROWSER_UI_PASSWORDS_DESTINATION_FILE_SYSTEM_H_

chrome/browser/ui/passwords/destination_file_system_unittest.cc

+// Copyright 2017 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/ui/passwords/destination_file_system.h"
+
+#include <memory>
+
+#include "base/files/file_util.h"
+#include "build/build_config.h"
+#include "chrome/test/base/testing_profile.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace {
+
+class DestinationFileSystemTest : public testing::Test {
+ public:
+  DestinationFileSystemTest() = default;
+  ~DestinationFileSystemTest() override = default;
+
+  void SetUp() override {
+    ASSERT_TRUE(base::CreateTemporaryFile(&temp_file_));
+    destination_ = std::make_unique<DestinationFileSystem>(temp_file_);
+  }
+
+  void TearDown() override { ASSERT_TRUE(base::DeleteFile(temp_file_, false)); }
+
+ protected:
+  base::FilePath temp_file_;
+  std::unique_ptr<DestinationFileSystem> destination_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(DestinationFileSystemTest);
+};
+
+TEST_F(DestinationFileSystemTest, WriteToFile) {
+  const std::string kData = "Anything";
+
+  destination_->Write(kData);
+
+  std::string actual_written;
+  base::ReadFileToString(temp_file_, &actual_written);
+  EXPECT_EQ(kData, actual_written);
+}
+
+TEST_F(DestinationFileSystemTest, WriteNothingToFile) {
+  const std::string kData;
+
+  destination_->Write(kData);
+
+  std::string actual_written;
+  base::ReadFileToString(temp_file_, &actual_written);
+  EXPECT_EQ(kData, actual_written);
+}
+
+}  // namespace

chrome/browser/ui/passwords/password_manager_porter.cc

@@ -9,7 +9,6 @@
 #include <utility>
 #include <vector>
 
-#include "base/files/file_util.h"
 #include "base/location.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/path_service.h"
@@ -18,6 +17,7 @@
 #include "chrome/browser/password_manager/password_store_factory.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/chrome_select_file_policy.h"
+#include "chrome/browser/ui/passwords/destination_file_system.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/grit/generated_resources.h"
 #include "components/password_manager/core/browser/export/password_csv_writer.h"
@@ -35,11 +35,6 @@
 
 namespace {
 
-// Wrapper for writing an std::string to a file.
-void WriteToFile(const base::FilePath& path, std::string data) {
-  base::WriteFile(path, data.c_str(), data.size());
-}
-
 // The following are not used on Android due to the |SelectFileDialog| being
 // unused.
 #if !defined(OS_ANDROID)
@@ -206,10 +201,14 @@ void PasswordManagerPorter::ExportPasswordsToPath(const base::FilePath& path) {
       credential_provider_interface_->GetAllPasswords();
   UMA_HISTOGRAM_COUNTS("PasswordManager.ExportedPasswordsPerUserInCSV",
                        password_list.size());
+  std::unique_ptr<DestinationFileSystem> destination(
+      new DestinationFileSystem(path));
+
   base::PostTaskWithTraits(
       FROM_HERE, {base::TaskPriority::USER_VISIBLE, base::MayBlock()},
-      base::Bind(
-          &WriteToFile, path,
+      base::BindOnce(
+          base::IgnoreResult(&DestinationFileSystem::Write),
+          base::Passed(std::move(destination)),
           base::Passed(password_manager::PasswordCSVWriter::SerializePasswords(
               password_list))));
 }

chrome/test/BUILD.gn

@@ -2423,6 +2423,7 @@ test("unit_tests") {
     "../browser/ui/find_bar/find_backend_unittest.cc",
     "../browser/ui/login/login_handler_unittest.cc",
     "../browser/ui/page_info/page_info_unittest.cc",
+    "../browser/ui/passwords/destination_file_system_unittest.cc",
     "../browser/ui/passwords/manage_passwords_state_unittest.cc",
     "../browser/ui/passwords/manage_passwords_view_utils_unittest.cc",
     "../browser/ui/passwords/password_access_authenticator_unittest.cc",

components/password_manager/core/browser/export/destination.h

@@ -5,6 +5,8 @@
 #ifndef COMPONENTS_PASSWORD_MANAGER_CORE_BROWSER_EXPORT_DESTINATION_H_
 #define COMPONENTS_PASSWORD_MANAGER_CORE_BROWSER_EXPORT_DESTINATION_H_
 
+#include <string>
+
 namespace password_manager {
 
 // Interface of a medium, to where a serialised list of passwords can be
@@ -13,8 +15,8 @@ class Destination {
  public:
   // Send the data to the destination, synchronously.
   virtual bool Write(const std::string& data) = 0;
-}
+};
 
 }  // namespace password_manager
 
-#endif  // COMPONENTS_PASSWORD_MANAGER_CORE_BROWSER_EXPORT_DESTINATION_H_
\ No newline at end of file
+#endif  // COMPONENTS_PASSWORD_MANAGER_CORE_BROWSER_EXPORT_DESTINATION_H_