Add Nearby Shared files into the holding space model

We want to give users a quick shortcut to access recent nearby shared
files within Tote. As user receives a file via nearby share, we should
be able to add them to the holding space model in a similar way we add
downloads as they are completed.

Bug: 1130625
Change-Id: Iba7ab69e7f8d9b7c05e740e8e4331b85a890b423
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2463584Reviewed-by: Toni Baržić <tbarzic@chromium.org>
Reviewed-by: Josh Nohle <nohle@chromium.org>
Commit-Queue: Ana Salazar <anasalazar@chromium.org>
Cr-Commit-Position: refs/heads/master@{#822896}

chrome/browser/nearby_sharing/nearby_notification_manager.cc

@@ -4,6 +4,7 @@
 
 #include "chrome/browser/nearby_sharing/nearby_notification_manager.h"
 
+#include "ash/public/cpp/ash_features.h"
 #include "base/files/file_util.h"
 #include "base/notreached.h"
 #include "base/strings/strcat.h"
@@ -22,6 +23,8 @@
 #include "chrome/browser/notifications/notification_display_service.h"
 #include "chrome/browser/platform_util.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/ui/ash/holding_space/holding_space_keyed_service.h"
+#include "chrome/browser/ui/ash/holding_space/holding_space_keyed_service_factory.h"
 #include "chrome/grit/generated_resources.h"
 #include "components/prefs/pref_service.h"
 #include "content/public/browser/browser_thread.h"
@@ -725,6 +728,18 @@ void NearbyNotificationManager::ShowIncomingSuccess(
   notification_display_service_->Display(
       NotificationHandler::Type::NEARBY_SHARE, notification,
       /*metadata=*/nullptr);
+
+  if (ash::features::IsTemporaryHoldingSpaceEnabled()) {
+    ash::HoldingSpaceKeyedService* holding_space_keyed_service =
+        ash::HoldingSpaceKeyedServiceFactory::GetInstance()->GetService(
+            profile_);
+    if (holding_space_keyed_service) {
+      for (const auto& file : share_target.file_attachments) {
+        if (file.file_path().has_value())
+          holding_space_keyed_service->AddNearbyShare(file.file_path().value());
+      }
+    }
+  }
 }
 
 void NearbyNotificationManager::ShowFailure(const ShareTarget& share_target) {

chrome/browser/nearby_sharing/nearby_notification_manager_unittest.cc

@@ -7,6 +7,10 @@
 #include <memory>
 #include <vector>
 
+#include "ash/public/cpp/ash_features.h"
+#include "ash/public/cpp/holding_space/holding_space_controller.h"
+#include "ash/public/cpp/holding_space/holding_space_item.h"
+#include "ash/public/cpp/holding_space/holding_space_model.h"
 #include "base/files/file_util.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/strings/strcat.h"
@@ -19,6 +23,7 @@
 #include "base/threading/thread_restrictions.h"
 #include "chrome/app/vector_icons/vector_icons.h"
 #include "chrome/browser/browser_features.h"
+#include "chrome/browser/chromeos/login/users/fake_chrome_user_manager.h"
 #include "chrome/browser/download/chrome_download_manager_delegate.h"
 #include "chrome/browser/download/download_core_service_factory.h"
 #include "chrome/browser/download/download_core_service_impl.h"
@@ -32,11 +37,21 @@
 #include "chrome/browser/nearby_sharing/transfer_metadata_builder.h"
 #include "chrome/browser/notifications/notification_display_service_factory.h"
 #include "chrome/browser/notifications/notification_display_service_tester.h"
+#include "chrome/browser/ui/ash/holding_space/fake_holding_space_color_provider.h"
+#include "chrome/browser/ui/ash/holding_space/holding_space_keyed_service_factory.h"
+#include "chrome/browser/ui/ash/holding_space/scoped_test_downloads_mount_point.h"
+#include "chrome/browser/ui/ash/test_session_controller.h"
 #include "chrome/grit/generated_resources.h"
+#include "chrome/test/base/testing_browser_process.h"
 #include "chrome/test/base/testing_profile.h"
+#include "chrome/test/base/testing_profile_manager.h"
+#include "components/account_id/account_id.h"
 #include "components/prefs/testing_pref_service.h"
+#include "components/sync_preferences/testing_pref_service_syncable.h"
 #include "content/public/test/browser_task_environment.h"
 #include "services/data_decoder/public/cpp/test_support/in_process_data_decoder.h"
+#include "storage/browser/file_system/external_mount_points.h"
+#include "storage/browser/file_system/file_system_context.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/skia/include/core/SkBitmap.h"
@@ -96,6 +111,13 @@ SkBitmap CreateTestSkBitmap() {
   return bitmap;
 }
 
+std::unique_ptr<TestingProfileManager> CreateTestingProfileManager() {
+  std::unique_ptr<TestingProfileManager> profile_manager(
+      new TestingProfileManager(TestingBrowserProcess::GetGlobal()));
+  EXPECT_TRUE(profile_manager->SetUp());
+  return profile_manager;
+}
+
 class NearbyNotificationManagerTest : public testing::Test {
  public:
   NearbyNotificationManagerTest() {
@@ -1118,3 +1140,96 @@ TEST_F(NearbyNotificationManagerTest,
   // Notification should be closed.
   EXPECT_EQ(0u, GetDisplayedNotifications().size());
 }
+
+class NearbyFilesHoldingSpaceTest : public testing::Test {
+ public:
+  NearbyFilesHoldingSpaceTest()
+      : session_controller_(std::make_unique<TestSessionController>()),
+        user_manager_(new chromeos::FakeChromeUserManager) {
+    scoped_feature_list_.InitWithFeatures(
+        {features::kNearbySharing, ash::features::kTemporaryHoldingSpace}, {});
+
+    holding_space_controller_ = std::make_unique<ash::HoldingSpaceController>(
+        std::make_unique<ash::holding_space::FakeHoldingSpaceColorProvider>());
+    profile_manager_ = CreateTestingProfileManager();
+    const AccountId account_id(AccountId::FromUserEmail(""));
+    user_manager_->AddUser(account_id);
+    user_manager_->LoginUser(account_id);
+    profile_ = profile_manager_->CreateTestingProfile("");
+  }
+
+  ~NearbyFilesHoldingSpaceTest() override = default;
+
+  // testing::Test:
+  void SetUp() override {
+    manager_ = std::make_unique<NearbyNotificationManager>(
+        NotificationDisplayServiceFactory::GetForProfile(profile_),
+        CreateAndUseMockNearbySharingService(profile_), profile_->GetPrefs(),
+        profile_);
+  }
+
+  NearbyNotificationManager* manager() { return manager_.get(); }
+
+  ash::HoldingSpaceModel* GetHoldingSpaceModel() const {
+    return holding_space_controller_ ? holding_space_controller_->model()
+                                     : nullptr;
+  }
+
+ protected:
+  base::test::ScopedFeatureList scoped_feature_list_;
+  content::BrowserTaskEnvironment task_environment_{
+      base::test::TaskEnvironment::TimeSource::MOCK_TIME};
+  std::unique_ptr<TestingProfileManager> profile_manager_;
+  TestingProfile* profile_;
+  std::unique_ptr<NearbyNotificationManager> manager_;
+  std::unique_ptr<TestSessionController> session_controller_;
+  std::unique_ptr<ash::HoldingSpaceController> holding_space_controller_;
+  chromeos::FakeChromeUserManager* user_manager_;
+};
+
+TEST_F(NearbyFilesHoldingSpaceTest, ShowSuccess_Files) {
+  ash::holding_space::ScopedTestDownloadsMountPoint downloads_mount(profile_);
+  ASSERT_TRUE(downloads_mount.IsValid());
+  ShareTarget share_target;
+  share_target.is_incoming = true;
+
+  const base::FilePath file_virtual_path("Sample.txt");
+  base::FilePath file_path =
+      downloads_mount.CreateFile(file_virtual_path, "Sample Text");
+
+  FileAttachment attachment(file_path);
+  share_target.file_attachments.push_back(std::move(attachment));
+
+  manager()->ShowSuccess(share_target);
+
+  ash::HoldingSpaceModel* holding_space_model = GetHoldingSpaceModel();
+  ASSERT_TRUE(holding_space_model);
+
+  ASSERT_EQ(share_target.file_attachments.size(),
+            holding_space_model->items().size());
+
+  for (int i = 0; i < share_target.file_attachments.size(); ++i) {
+    ash::HoldingSpaceItem* holding_space_item =
+        holding_space_model->items()[i].get();
+    EXPECT_EQ(ash::HoldingSpaceItem::Type::kNearbyShare,
+              holding_space_item->type());
+
+    EXPECT_EQ(share_target.file_attachments[i].file_path(),
+              holding_space_item->file_path());
+  }
+}
+
+TEST_F(NearbyFilesHoldingSpaceTest, ShowSuccess_Text) {
+  ShareTarget share_target;
+  share_target.is_incoming = true;
+
+  TextAttachment attachment(TextAttachment::Type::kText, "Sample Text");
+  share_target.text_attachments.push_back(std::move(attachment));
+
+  manager()->ShowSuccess(share_target);
+
+  ash::HoldingSpaceModel* holding_space_model = GetHoldingSpaceModel();
+  ASSERT_TRUE(holding_space_model);
+
+  EXPECT_TRUE(holding_space_model->items().empty());
+}

chrome/browser/ui/ash/holding_space/BUILD.gn

@@ -36,8 +36,12 @@ source_set("test_support") {
   testonly = true
 
   sources = [
+    "//chrome/browser/ui/ash/holding_space/fake_holding_space_color_provider.cc",
+    "//chrome/browser/ui/ash/holding_space/fake_holding_space_color_provider.h",
     "//chrome/browser/ui/ash/holding_space/holding_space_browsertest_base.cc",
     "//chrome/browser/ui/ash/holding_space/holding_space_browsertest_base.h",
+    "//chrome/browser/ui/ash/holding_space/scoped_test_downloads_mount_point.cc",
+    "//chrome/browser/ui/ash/holding_space/scoped_test_downloads_mount_point.h",
   ]
 
   deps = [

chrome/browser/ui/ash/holding_space/fake_holding_space_color_provider.cc

+// Copyright 2020 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/ash/holding_space/fake_holding_space_color_provider.h"
+
+#include "base/files/file_util.h"
+#include "chrome/browser/chromeos/file_manager/app_id.h"
+#include "chrome/browser/chromeos/file_manager/fileapi_util.h"
+#include "chrome/browser/chromeos/file_manager/path_util.h"
+#include "storage/browser/file_system/external_mount_points.h"
+#include "storage/browser/file_system/file_system_context.h"
+
+namespace ash {
+namespace holding_space {
+
+SkColor FakeHoldingSpaceColorProvider::GetBackgroundColor() const {
+  return SkColor();
+}
+SkColor FakeHoldingSpaceColorProvider::GetFileIconColor() const {
+  return SkColor();
+}
+
+}  // namespace holding_space
+}  // namespace ash
\ No newline at end of file

chrome/browser/ui/ash/holding_space/fake_holding_space_color_provider.h

+// Copyright 2020 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_ASH_HOLDING_SPACE_FAKE_HOLDING_SPACE_COLOR_PROVIDER_H_
+#define CHROME_BROWSER_UI_ASH_HOLDING_SPACE_FAKE_HOLDING_SPACE_COLOR_PROVIDER_H_
+
+#include "ash/public/cpp/holding_space/holding_space_color_provider.h"
+
+namespace ash {
+namespace holding_space {
+
+class FakeHoldingSpaceColorProvider : public ash::HoldingSpaceColorProvider {
+ public:
+  FakeHoldingSpaceColorProvider() = default;
+  FakeHoldingSpaceColorProvider(const FakeHoldingSpaceColorProvider&) = delete;
+  FakeHoldingSpaceColorProvider& operator=(
+      const FakeHoldingSpaceColorProvider&) = delete;
+  ~FakeHoldingSpaceColorProvider() override = default;
+
+  // ash::HoldingSpaceColorProvider:
+  SkColor GetBackgroundColor() const override;
+  SkColor GetFileIconColor() const override;
+};
+
+}  // namespace holding_space
+}  // namespace ash
+
+#endif  // CHROME_BROWSER_UI_ASH_HOLDING_SPACE_FAKE_HOLDING_SPACE_COLOR_PROVIDER_H_
\ No newline at end of file

chrome/browser/ui/ash/holding_space/holding_space_keyed_service_unittest.cc

@@ -22,6 +22,7 @@
 #include "base/test/bind_test_util.h"
 #include "base/test/scoped_feature_list.h"
 #include "base/test/simple_test_clock.h"
+#include "chrome/browser/browser_features.h"
 #include "chrome/browser/chromeos/file_manager/app_id.h"
 #include "chrome/browser/chromeos/file_manager/fileapi_util.h"
 #include "chrome/browser/chromeos/file_manager/path_util.h"
@@ -32,6 +33,7 @@
 #include "chrome/browser/ui/ash/holding_space/holding_space_keyed_service_factory.h"
 #include "chrome/browser/ui/ash/holding_space/holding_space_persistence_delegate.h"
 #include "chrome/browser/ui/ash/holding_space/holding_space_util.h"
+#include "chrome/browser/ui/ash/holding_space/scoped_test_downloads_mount_point.h"
 #include "chrome/test/base/browser_with_test_window_test.h"
 #include "chrome/test/base/testing_profile_manager.h"
 #include "components/account_id/account_id.h"
@@ -62,40 +64,6 @@ std::vector<HoldingSpaceItem::Type> GetHoldingSpaceItemTypes() {
   return types;
 }
 
-// Utility class that registers the downloads external file system mount point,
-// and grants file manager app access permission for the mount point.
-class ScopedDownloadsMountPoint {
- public:
-  explicit ScopedDownloadsMountPoint(Profile* profile)
-      : name_(file_manager::util::GetDownloadsMountPointName(profile)) {
-    if (!temp_dir_.CreateUniqueTempDir())
-      return;
-
-    storage::ExternalMountPoints::GetSystemInstance()->RegisterFileSystem(
-        name_, storage::kFileSystemTypeNativeLocal,
-        storage::FileSystemMountOption(), temp_dir_.GetPath());
-    file_manager::util::GetFileSystemContextForExtensionId(
-        profile, file_manager::kFileManagerAppId)
-        ->external_backend()
-        ->GrantFileAccessToExtension(file_manager::kFileManagerAppId,
-                                     base::FilePath(name_));
-  }
-
-  ~ScopedDownloadsMountPoint() {
-    storage::ExternalMountPoints::GetSystemInstance()->RevokeFileSystem(name_);
-  }
-
-  bool IsValid() const { return temp_dir_.IsValid(); }
-
-  const base::FilePath& GetRootPath() const { return temp_dir_.GetPath(); }
-
-  const std::string& name() const { return name_; }
-
- private:
-  base::ScopedTempDir temp_dir_;
-  std::string name_;
-};
-
 // Utility class which can wait until a `HoldingSpaceModel` for a given profile
 // is attached to the `HoldingSpaceController`.
 class HoldingSpaceModelAttachedWaiter : public HoldingSpaceControllerObserver {
@@ -230,28 +198,6 @@ class HoldingSpaceKeyedServiceTest : public BrowserWithTestWindowTest {
     return ash_test_helper()->test_session_controller_client();
   }
 
-  // Creates a file under path |mount_point|/|relative_path| with the provided
-  // content. Returns the created file's file path, or an empty path on failure.
-  base::FilePath CreateFile(const ScopedDownloadsMountPoint& mount_point,
-                            const base::FilePath& relative_path,
-                            const std::string& content) {
-    const base::FilePath path = mount_point.GetRootPath().Append(relative_path);
-    if (!base::CreateDirectory(path.DirName()))
-      return base::FilePath();
-    if (!base::WriteFile(path, content))
-      return base::FilePath();
-    return path;
-  }
-
-  // Creates an arbitrary file under the specified 'mount_point'.
-  base::FilePath CreateArbitraryFile(
-      const ScopedDownloadsMountPoint& mount_point) {
-    return CreateFile(
-        mount_point,
-        base::FilePath(base::UnguessableToken::Create().ToString()),
-        /*content=*/std::string());
-  }
-
   // Resolves an absolute file path in the file manager's file system context,
   // and returns the file's file system URL.
   GURL GetFileSystemUrl(Profile* profile,
@@ -352,7 +298,7 @@ class HoldingSpaceKeyedServiceTest : public BrowserWithTestWindowTest {
 // manager app.
 TEST_F(HoldingSpaceKeyedServiceTest, AddScreenshotItem) {
   // Create a test downloads mount point.
-  ScopedDownloadsMountPoint downloads_mount(GetProfile());
+  holding_space::ScopedTestDownloadsMountPoint downloads_mount(GetProfile());
   ASSERT_TRUE(downloads_mount.IsValid());
 
   // Wait for the holding space model.
@@ -371,7 +317,7 @@ TEST_F(HoldingSpaceKeyedServiceTest, AddScreenshotItem) {
   // test will try to resolve the file's file system URL, which fails if the
   // file does not exist.
   const base::FilePath item_1_full_path =
-      CreateFile(downloads_mount, item_1_virtual_path, "red");
+      downloads_mount.CreateFile(item_1_virtual_path, "red");
   ASSERT_FALSE(item_1_full_path.empty());
 
   holding_space_service->AddScreenshot(item_1_full_path);
@@ -382,7 +328,7 @@ TEST_F(HoldingSpaceKeyedServiceTest, AddScreenshotItem) {
   // test will try to resolve the file's file system URL, which fails if the
   // file does not exist.
   const base::FilePath item_2_full_path =
-      CreateFile(downloads_mount, item_2_virtual_path, "blue");
+      downloads_mount.CreateFile(item_2_virtual_path, "blue");
   ASSERT_FALSE(item_2_full_path.empty());
   holding_space_service->AddScreenshot(item_2_full_path);
 
@@ -453,7 +399,7 @@ TEST_F(HoldingSpaceKeyedServiceTest, SecondaryUserProfile) {
 // Verifies that updates to the holding space model are persisted.
 TEST_F(HoldingSpaceKeyedServiceTest, UpdatePersistentStorage) {
   // Create a file system mount point.
-  ScopedDownloadsMountPoint downloads_mount(GetProfile());
+  holding_space::ScopedTestDownloadsMountPoint downloads_mount(GetProfile());
   ASSERT_TRUE(downloads_mount.IsValid());
 
   HoldingSpaceKeyedService* const primary_holding_space_service =
@@ -468,7 +414,7 @@ TEST_F(HoldingSpaceKeyedServiceTest, UpdatePersistentStorage) {
 
   // Verify persistent storage is updated when adding each type of item.
   for (const HoldingSpaceItem::Type type : GetHoldingSpaceItemTypes()) {
-    const base::FilePath file_path = CreateArbitraryFile(downloads_mount);
+    const base::FilePath file_path = downloads_mount.CreateArbitraryFile();
     const GURL file_system_url = GetFileSystemUrl(GetProfile(), file_path);
 
     auto holding_space_item = HoldingSpaceItem::CreateFileBackedItem(
@@ -504,7 +450,7 @@ TEST_F(HoldingSpaceKeyedServiceTest, UpdatePersistentStorage) {
 // any stale holding space items are removed.
 TEST_F(HoldingSpaceKeyedServiceTest, RestorePersistentStorage) {
   // Create file system mount point.
-  ScopedDownloadsMountPoint downloads_mount(GetProfile());
+  holding_space::ScopedTestDownloadsMountPoint downloads_mount(GetProfile());
   ASSERT_TRUE(downloads_mount.IsValid());
 
   HoldingSpaceKeyedService* const primary_holding_space_service =
@@ -521,7 +467,7 @@ TEST_F(HoldingSpaceKeyedServiceTest, RestorePersistentStorage) {
 
         // Persist some holding space items of each type.
         for (const HoldingSpaceItem::Type type : GetHoldingSpaceItemTypes()) {
-          const base::FilePath file = CreateArbitraryFile(downloads_mount);
+          const base::FilePath file = downloads_mount.CreateArbitraryFile();
           const GURL file_system_url = GetFileSystemUrl(GetProfile(), file);
 
           auto fresh_holding_space_item =
@@ -603,7 +549,7 @@ TEST_F(HoldingSpaceKeyedServiceTest, RestorePersistentStorage) {
 // kMaxFileAge.
 TEST_F(HoldingSpaceKeyedServiceTest, RemoveOlderFilesFromPersistance) {
   // Create file system mount point.
-  ScopedDownloadsMountPoint downloads_mount(GetProfile());
+  holding_space::ScopedTestDownloadsMountPoint downloads_mount(GetProfile());
   ASSERT_TRUE(downloads_mount.IsValid());
 
   HoldingSpaceKeyedService* const primary_holding_space_service =
@@ -620,7 +566,7 @@ TEST_F(HoldingSpaceKeyedServiceTest, RemoveOlderFilesFromPersistance) {
 
         // Persist some holding space items of each type.
         for (const HoldingSpaceItem::Type type : GetHoldingSpaceItemTypes()) {
-          const base::FilePath file = CreateArbitraryFile(downloads_mount);
+          const base::FilePath file = downloads_mount.CreateArbitraryFile();
           const GURL file_system_url = GetFileSystemUrl(GetProfile(), file);
 
           auto fresh_holding_space_item =
@@ -704,7 +650,7 @@ TEST_F(HoldingSpaceKeyedServiceTest, RemoveOlderFilesFromPersistance) {
 TEST_F(HoldingSpaceKeyedServiceTest, AddDownloadItem) {
   TestingProfile* profile = GetProfile();
   // Create a test downloads mount point.
-  ScopedDownloadsMountPoint downloads_mount(profile);
+  holding_space::ScopedTestDownloadsMountPoint downloads_mount(profile);
   ASSERT_TRUE(downloads_mount.IsValid());
 
   // Create a fake download file on the local file system - later parts of the
@@ -712,7 +658,7 @@ TEST_F(HoldingSpaceKeyedServiceTest, AddDownloadItem) {
   // file does not exist.
   const base::FilePath download_item_virtual_path("Download 1.png");
   const base::FilePath download_item_full_path =
-      CreateFile(downloads_mount, download_item_virtual_path, "download 1");
+      downloads_mount.CreateFile(download_item_virtual_path, "download 1");
 
   MockDownloadManager* mock_download_manager = download_manager();
   std::unique_ptr<download::MockDownloadItem> item(
@@ -761,4 +707,94 @@ TEST_F(HoldingSpaceKeyedServiceTest, AddDownloadItem) {
                                   downloads_mount.name()));
 }
 
+class HoldingSpaceKeyedServiceNearbySharingTest
+    : public HoldingSpaceKeyedServiceTest {
+ public:
+  HoldingSpaceKeyedServiceNearbySharingTest() {
+    scoped_feature_list_.InitWithFeatures(
+        {::features::kNearbySharing, ash::features::kTemporaryHoldingSpace},
+        {});
+  }
+
+  ~HoldingSpaceKeyedServiceNearbySharingTest() override = default;
+
+ private:
+  base::test::ScopedFeatureList scoped_feature_list_;
+};
+
+TEST_F(HoldingSpaceKeyedServiceNearbySharingTest, AddNearbyShareItem) {
+  // Create a test downloads mount point.
+  holding_space::ScopedTestDownloadsMountPoint downloads_mount(GetProfile());
+  ASSERT_TRUE(downloads_mount.IsValid());
+
+  // Wait for the holding space model.
+  HoldingSpaceModelAttachedWaiter(GetProfile()).Wait();
+
+  // Verify that the holding space model gets set even if the holding space
+  // keyed service is not explicitly created.
+  HoldingSpaceModel* const initial_model =
+      HoldingSpaceController::Get()->model();
+  EXPECT_TRUE(initial_model);
+
+  HoldingSpaceKeyedService* const holding_space_service =
+      HoldingSpaceKeyedServiceFactory::GetInstance()->GetService(GetProfile());
+  const base::FilePath item_1_virtual_path("File 1.png");
+  // Create a fake nearby shared file on the local file system - later parts of
+  // the test will try to resolve the file's file system URL, which fails if the
+  // file does not exist.
+  const base::FilePath item_1_full_path =
+      downloads_mount.CreateFile(item_1_virtual_path, "red");
+  ASSERT_FALSE(item_1_full_path.empty());
+
+  holding_space_service->AddNearbyShare(item_1_full_path);
+
+  const base::FilePath item_2_virtual_path = base::FilePath("Alt/File 2.png");
+  // Create a fake nearby shared file on the local file system - later parts of
+  // the test will try to resolve the file's file system URL, which fails if the
+  // file does not exist.
+  const base::FilePath item_2_full_path =
+      downloads_mount.CreateFile(item_2_virtual_path, "blue");
+  ASSERT_FALSE(item_2_full_path.empty());
+  holding_space_service->AddNearbyShare(item_2_full_path);
+
+  EXPECT_EQ(initial_model, HoldingSpaceController::Get()->model());
+  EXPECT_EQ(HoldingSpaceController::Get()->model(),
+            holding_space_service->model_for_testing());
+
+  HoldingSpaceModel* const model = HoldingSpaceController::Get()->model();
+  ASSERT_EQ(2u, model->items().size());
+
+  const HoldingSpaceItem* item_1 = model->items()[0].get();
+  EXPECT_EQ(item_1_full_path, item_1->file_path());
+  EXPECT_TRUE(gfx::BitmapsAreEqual(
+      *holding_space_util::ResolveImage(
+           holding_space_service->thumbnail_loader_for_testing(),
+           HoldingSpaceItem::Type::kNearbyShare, item_1_full_path)
+           ->image_skia()
+           .bitmap(),
+      *item_1->image().image_skia().bitmap()));
+  // Verify the item file system URL resolves to the correct file in the file
+  // manager's context.
+  EXPECT_EQ(
+      item_1_virtual_path,
+      GetVirtualPathFromUrl(item_1->file_system_url(), downloads_mount.name()));
+  EXPECT_EQ(base::ASCIIToUTF16("File 1.png"), item_1->text());
+
+  const HoldingSpaceItem* item_2 = model->items()[1].get();
+  EXPECT_EQ(item_2_full_path, item_2->file_path());
+  EXPECT_TRUE(gfx::BitmapsAreEqual(
+      *holding_space_util::ResolveImage(
+           holding_space_service->thumbnail_loader_for_testing(),
+           HoldingSpaceItem::Type::kNearbyShare, item_2_full_path)
+           ->image_skia()
+           .bitmap(),
+      *item_2->image().image_skia().bitmap()));
+  // Verify the item file system URL resolves to the correct file in the file
+  // manager's context.
+  EXPECT_EQ(
+      item_2_virtual_path,
+      GetVirtualPathFromUrl(item_2->file_system_url(), downloads_mount.name()));
+  EXPECT_EQ(base::ASCIIToUTF16("File 2.png"), item_2->text());
+}
+
 }  // namespace ash

chrome/browser/ui/ash/holding_space/scoped_test_downloads_mount_point.cc

+// Copyright 2020 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/ash/holding_space/scoped_test_downloads_mount_point.h"
+
+#include "base/files/file_util.h"
+#include "chrome/browser/chromeos/file_manager/app_id.h"
+#include "chrome/browser/chromeos/file_manager/fileapi_util.h"
+#include "chrome/browser/chromeos/file_manager/path_util.h"
+#include "storage/browser/file_system/external_mount_points.h"
+#include "storage/browser/file_system/file_system_context.h"
+
+namespace ash {
+namespace holding_space {
+ScopedTestDownloadsMountPoint::ScopedTestDownloadsMountPoint(Profile* profile)
+    : name_(file_manager::util::GetDownloadsMountPointName(profile)) {
+  if (!temp_dir_.CreateUniqueTempDir())
+    return;
+
+  storage::ExternalMountPoints::GetSystemInstance()->RegisterFileSystem(
+      name_, storage::kFileSystemTypeNativeLocal,
+      storage::FileSystemMountOption(), temp_dir_.GetPath());
+  file_manager::util::GetFileSystemContextForExtensionId(
+      profile, file_manager::kFileManagerAppId)
+      ->external_backend()
+      ->GrantFileAccessToExtension(file_manager::kFileManagerAppId,
+                                   base::FilePath(name_));
+}
+
+ScopedTestDownloadsMountPoint::~ScopedTestDownloadsMountPoint() {
+  storage::ExternalMountPoints::GetSystemInstance()->RevokeFileSystem(name_);
+}
+
+base::FilePath ScopedTestDownloadsMountPoint::CreateFile(
+    const base::FilePath& relative_path,
+    const std::string& content) {
+  const base::FilePath path = GetRootPath().Append(relative_path);
+  if (!base::CreateDirectory(path.DirName()))
+    return base::FilePath();
+  if (!base::WriteFile(path, content))
+    return base::FilePath();
+  return path;
+}
+
+base::FilePath ScopedTestDownloadsMountPoint::CreateArbitraryFile() {
+  return CreateFile(base::FilePath(base::UnguessableToken::Create().ToString()),
+                    /*content=*/std::string());
+}
+
+}  // namespace holding_space
+}  // namespace ash
\ No newline at end of file

chrome/browser/ui/ash/holding_space/scoped_test_downloads_mount_point.h

+// Copyright 2020 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_ASH_HOLDING_SPACE_SCOPED_TEST_DOWNLOADS_MOUNT_POINT_H_
+#define CHROME_BROWSER_UI_ASH_HOLDING_SPACE_SCOPED_TEST_DOWNLOADS_MOUNT_POINT_H_
+
+#include <memory>
+
+#include "base/files/scoped_temp_dir.h"
+
+class GURL;
+class Profile;
+
+namespace base {
+class FilePath;
+}  // namespace base
+
+namespace ash {
+namespace holding_space {
+
+// Utility class that registers the downloads external file system mount point,
+// and grants file manager app access permission for the mount point.
+class ScopedTestDownloadsMountPoint {
+ public:
+  explicit ScopedTestDownloadsMountPoint(Profile* profile);
+  ScopedTestDownloadsMountPoint(const ScopedTestDownloadsMountPoint&) = delete;
+  ScopedTestDownloadsMountPoint& operator=(
+      const ScopedTestDownloadsMountPoint&) = delete;
+  ~ScopedTestDownloadsMountPoint();
+
+  bool IsValid() const { return temp_dir_.IsValid(); }
+
+  const base::FilePath& GetRootPath() const { return temp_dir_.GetPath(); }
+
+  const std::string& name() const { return name_; }
+
+  // Creates a file under [mount point root path]/|relative_path| with the
+  // provided content. Returns the created file's file path, or an empty path on
+  // failure.
+  base::FilePath CreateFile(const base::FilePath& relative_path,
+                            const std::string& content);
+
+  // Creates an arbitrary file under the 'mount_point'.
+  base::FilePath CreateArbitraryFile();
+
+ private:
+  base::ScopedTempDir temp_dir_;
+  std::string name_;
+};
+
+}  // namespace holding_space
+}  // namespace ash
+
+#endif  // CHROME_BROWSER_UI_ASH_HOLDING_SPACE_SCOPED_TEST_DOWNLOADS_MOUNT_POINT_H_
\ No newline at end of file

chrome/test/BUILD.gn

@@ -5017,6 +5017,7 @@ test("unit_tests") {
       "//chrome/browser/resources/chromeos/zip_archiver/cpp:ziparchiver_unittests",
       "//chrome/browser/ui/app_list/search/search_result_ranker:app_launch_predictor_proto",
       "//chrome/browser/ui/app_list/search/search_result_ranker:recurrence_ranker_proto",
+      "//chrome/browser/ui/ash/holding_space:test_support",
       "//chrome/services/printing:pdf_thumbnailer_test",
       "//chrome/services/sharing:unit_tests",
       "//chrome/services/sharing/nearby:unit_tests",