[Bluetooth] Add unittest for bluetooth tray list.

This CL is a followup to https://crrev.com/c/2482443.
This adds simple unittest that verifies that device
scroll list in bluetooth tray view is updated correctly.

Fixed: 1141995
Change-Id: I8237871ff6c06f864a804d106a0556d3552b6109
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2508234Reviewed-by: James Cook <jamescook@chromium.org>
Commit-Queue: Azeem Arshad <azeemarshad@chromium.org>
Cr-Commit-Position: refs/heads/master@{#826377}

ash/BUILD.gn

@@ -2149,6 +2149,7 @@ test("ash_unittests") {
     "system/bluetooth/bluetooth_notification_controller_unittest.cc",
     "system/bluetooth/bluetooth_power_controller_unittest.cc",
     "system/bluetooth/tray_bluetooth_helper_legacy_unittest.cc",
+    "system/bluetooth/unified_bluetooth_detailed_view_controller_unittest.cc",
     "system/caps_lock_notification_controller_unittest.cc",
     "system/gesture_education/gesture_education_notification_controller_unittest.cc",
     "system/holding_space/holding_space_tray_unittest.cc",

ash/system/bluetooth/bluetooth_detailed_view.cc

@@ -245,7 +245,7 @@ void BluetoothDetailedView::UpdateDeviceScrollList(
     } else {
       scroll_content()->ReorderChildView(bluetooth_discovering_label_, index++);
     }
-  } else {
+  } else if (bluetooth_discovering_label_) {
     scroll_content()->RemoveChildView(bluetooth_discovering_label_);
     bluetooth_discovering_label_ = nullptr;
   }
@@ -273,6 +273,7 @@ const char* BluetoothDetailedView::GetClassName() const {
 
 void BluetoothDetailedView::CreateItems() {
   CreateScrollableList();
+  scroll_content()->SetID(kScrollContentID);
   CreateTitleRow(IDS_ASH_STATUS_TRAY_BLUETOOTH);
 }
 

ash/system/bluetooth/bluetooth_detailed_view.h

@@ -25,6 +25,9 @@ namespace tray {
 
 class BluetoothDetailedView : public TrayDetailedView {
  public:
+  // ID for scroll content view. Used in testing.
+  static const int kScrollContentID = 1;
+
   BluetoothDetailedView(DetailedViewDelegate* delegate, LoginStatus login);
 
   ~BluetoothDetailedView() override;

ash/system/bluetooth/unified_bluetooth_detailed_view_controller.h

@@ -7,6 +7,7 @@
 
 #include <memory>
 
+#include "ash/ash_export.h"
 #include "ash/system/bluetooth/tray_bluetooth_helper.h"
 #include "ash/system/unified/detailed_view_controller.h"
 #include "base/macros.h"
@@ -22,7 +23,7 @@ class DetailedViewDelegate;
 class UnifiedSystemTrayController;
 
 // Controller of Bluetooth detailed view in UnifiedSystemTray.
-class UnifiedBluetoothDetailedViewController
+class ASH_EXPORT UnifiedBluetoothDetailedViewController
     : public DetailedViewController,
       public TrayBluetoothHelper::Observer {
  public:

ash/system/bluetooth/unified_bluetooth_detailed_view_controller_unittest.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 "ash/system/bluetooth/unified_bluetooth_detailed_view_controller.h"
+
+#include <memory>
+
+#include "ash/system/bluetooth/bluetooth_detailed_view.h"
+#include "ash/system/bluetooth/tray_bluetooth_helper.h"
+#include "ash/system/unified/unified_system_tray_controller.h"
+#include "ash/system/unified/unified_system_tray_model.h"
+#include "ash/test/ash_test_base.h"
+#include "device/bluetooth/dbus/bluez_dbus_manager.h"
+#include "device/bluetooth/dbus/fake_bluetooth_adapter_client.h"
+#include "device/bluetooth/dbus/fake_bluetooth_device_client.h"
+#include "ui/views/view.h"
+
+namespace ash {
+
+namespace {
+
+const base::TimeDelta kUpdateFrequencyMs =
+    base::TimeDelta::FromMilliseconds(1000);
+
+}  // namespace
+
+class UnifiedBluetoothDetailedViewControllerTest : public AshTestBase {
+ public:
+  UnifiedBluetoothDetailedViewControllerTest()
+      : AshTestBase(base::test::TaskEnvironment::TimeSource::MOCK_TIME) {}
+  UnifiedBluetoothDetailedViewControllerTest(
+      const UnifiedBluetoothDetailedViewControllerTest&) = delete;
+  UnifiedBluetoothDetailedViewControllerTest& operator=(
+      const UnifiedBluetoothDetailedViewControllerTest&) = delete;
+  ~UnifiedBluetoothDetailedViewControllerTest() override = default;
+
+  void SetUp() override {
+    bluez::BluezDBusManager::InitializeFake();
+    AshTestBase::SetUp();
+
+    // Set fake adapter client to powered-on and initialize with zero simulation
+    // interval.
+    adapter_client_ = static_cast<bluez::FakeBluetoothAdapterClient*>(
+        bluez::BluezDBusManager::Get()->GetBluetoothAdapterClient());
+    adapter_client_->SetSimulationIntervalMs(0);
+    adapter_client_
+        ->GetProperties(
+            dbus::ObjectPath(bluez::FakeBluetoothAdapterClient::kAdapterPath))
+        ->powered.ReplaceValue(true);
+
+    // Enable fake device client and initialize with zero simulation interval.
+    device_client_ = static_cast<bluez::FakeBluetoothDeviceClient*>(
+        bluez::BluezDBusManager::Get()->GetBluetoothDeviceClient());
+    device_client_->SetSimulationIntervalMs(0);
+    task_environment()->RunUntilIdle();
+
+    tray_model_ = std::make_unique<UnifiedSystemTrayModel>(nullptr);
+    tray_controller_ =
+        std::make_unique<UnifiedSystemTrayController>(tray_model_.get());
+    bt_detailed_view_controller_ =
+        std::make_unique<UnifiedBluetoothDetailedViewController>(
+            tray_controller_.get());
+  }
+
+  void TearDown() override {
+    bt_detailed_view_controller_.reset();
+    tray_controller_.reset();
+    tray_model_.reset();
+    AshTestBase::TearDown();
+  }
+
+  void AddTestDevice() {
+    bluez::FakeBluetoothDeviceClient::IncomingDeviceProperties props;
+    props.device_path = "/fake/hci0/dev123";
+    props.device_address = "00:00:00:00:00:01";
+    props.device_name = "Test Device";
+    props.device_class = 0x000104;
+    device_client_->CreateDeviceWithProperties(
+        dbus::ObjectPath(bluez::FakeBluetoothAdapterClient::kAdapterPath),
+        props);
+  }
+
+  UnifiedBluetoothDetailedViewController* bt_detailed_view_controller() {
+    return bt_detailed_view_controller_.get();
+  }
+
+ private:
+  bluez::FakeBluetoothAdapterClient* adapter_client_;
+  bluez::FakeBluetoothDeviceClient* device_client_;
+  std::unique_ptr<UnifiedSystemTrayModel> tray_model_;
+  std::unique_ptr<UnifiedSystemTrayController> tray_controller_;
+  std::unique_ptr<UnifiedBluetoothDetailedViewController>
+      bt_detailed_view_controller_;
+};
+
+TEST_F(UnifiedBluetoothDetailedViewControllerTest, UpdateScrollListTest) {
+  tray::BluetoothDetailedView* bluetooth_detailed_view =
+      static_cast<tray::BluetoothDetailedView*>(
+          bt_detailed_view_controller()->CreateView());
+  task_environment()->FastForwardBy(kUpdateFrequencyMs);
+
+  // Verify that default devices simulated by FakeBluetoothDeviceClient are
+  // displayed.
+  const views::View* scroll_content = bluetooth_detailed_view->GetViewByID(
+      tray::BluetoothDetailedView::kScrollContentID);
+  const size_t scroll_content_size = scroll_content->children().size();
+  // Expect at least 1 paired device, 1 unpaired device and 2 headers.
+  EXPECT_GE(scroll_content_size, 4u);
+
+  // Fast forward to next bluetooth list sync and verify that child views
+  // are re-used after update.
+  views::View* scroll_content_child = scroll_content->children()[1];
+  task_environment()->FastForwardBy(kUpdateFrequencyMs);
+  EXPECT_EQ(scroll_content_child, scroll_content->children()[1]);
+
+  // Verify that newly added devices is displayed.
+  AddTestDevice();
+  task_environment()->FastForwardBy(kUpdateFrequencyMs);
+  EXPECT_EQ(scroll_content_size + 1u, scroll_content->children().size());
+}
+
+}  // namespace ash
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