[Night Light] CL2: Ash and system tray work

ash/system/night_light/night_light_controller_unittest.cc

Index: ash/system/night_light/night_light_controller_unittest.cc
diff --git a/ash/system/night_light/night_light_controller_unittest.cc b/ash/system/night_light/night_light_controller_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e7f51787b62948651780edf1ee69374c3ae7d5c6
--- /dev/null
+++ b/ash/system/night_light/night_light_controller_unittest.cc
@@ -0,0 +1,135 @@
+// 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 "ash/system/night_light/night_light_controller.h"
+#include "ash/public/cpp/config.h"
+#include "ash/public/cpp/session_types.h"
+#include "ash/shell.h"
+#include "ash/test/ash_test_base.h"
+#include "ash/test/ash_test_helper.h"
+#include "ash/test/test_session_controller_client.h"
+#include "ash/test/test_shell_delegate.h"
+#include "base/macros.h"
+#include "components/prefs/testing_pref_service.h"
+#include "ui/compositor/layer.h"
+
+namespace ash {
+
+namespace {
+
+constexpr char user_1_email[] = "user1@nightlight";
+constexpr char user_2_email[] = "user2@nightlight";
+
+NightLightController* GetController() {
+  return Shell::Get()->night_light_controller();
+}
+
+// Tests that the color temperatures of all root layers are equal to the given
+// |expected_temperature| and returns true if so, or false otherwise.
+bool TestLayersTemperature(float expected_temperature) {
+  for (aura::Window* root_window : ash::Shell::GetAllRootWindows()) {
+    ui::Layer* layer = root_window->layer();
+    if (expected_temperature != layer->layer_temperature())
+      return false;
+  }
+
+  return true;
+}
+
+class TestObserver : public NightLightController::Observer {
+ public:
+  TestObserver() { GetController()->AddObserver(this); }
+  ~TestObserver() override { GetController()->RemoveObserver(this); }
+
+  // ash::NightLightController::Observer:
+  void OnNightLightEnabledChanged(bool enabled) override { status_ = enabled; }
+
+  bool status() const { return status_; }
+
+ private:
+  bool status_ = false;
+
+  DISALLOW_COPY_AND_ASSIGN(TestObserver);
+};
+
+class NightLightTest : public test::AshTestBase {
+ public:
+  NightLightTest() = default;
+  ~NightLightTest() override = default;
+
+  void CreateTestUserSessions() {
+    GetSessionControllerClient()->Reset();
+    GetSessionControllerClient()->AddUserSession(user_1_email);
+    GetSessionControllerClient()->AddUserSession(user_2_email);
+  }
+
+  void SwitchActiveUser(const std::string& email) {
+    GetSessionControllerClient()->SwitchActiveUser(
+        AccountId::FromUserEmail(email));
+  }
+
+  void InjectTestPrefService(PrefService* pref_service) {
+    ash_test_helper()->test_shell_delegate()->set_active_user_pref_service(
+        pref_service);
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(NightLightTest);
+};
+
+// Tests toggling NightLight on / off and makes sure the observer is updated and
+// the layer temperatures are modified.
+TEST_F(NightLightTest, TestToggle) {
+  UpdateDisplay("800x600,800x600");
+
+  TestObserver observer;
+  NightLightController* controller = GetController();
+  ASSERT_FALSE(controller->enabled());
+  EXPECT_TRUE(TestLayersTemperature(0.0f));
+  controller->Toggle();

[James Cook, 2017/05/08 16:09:07]

optional: I think tests are clearer when they explicitly call SetEnabled()
instead of Toggle(), because then the reader doesn't have to think about the old
vs. new state.

[afakhry, 2017/05/08 17:36:26]

Since I want to test Toggle() here, I added an explicit SetEnabled(false) at the
beginning of this test to explicitly specify the initial state.

+  EXPECT_TRUE(controller->enabled());
+  EXPECT_TRUE(observer.status());
+  EXPECT_TRUE(TestLayersTemperature(GetController()->color_temperature()));
+  controller->Toggle();
+  EXPECT_FALSE(controller->enabled());
+  EXPECT_FALSE(observer.status());
+  EXPECT_TRUE(TestLayersTemperature(0.0f));
+}
+
+// Tests that switching users retrieves NightLight settings for the active
+// user's prefs.
+TEST_F(NightLightTest, TestUserSwitchAndSettingsPersistence) {
+  if (Shell::GetAshConfig() == Config::MASH) {
+    // User switching doesn't work on mash.
+    return;
+  }
+
+  CreateTestUserSessions();
+  TestingPrefServiceSimple user_1_pref_service;
+  TestingPrefServiceSimple user_2_pref_service;
+  NightLightController::RegisterPrefs(user_1_pref_service.registry());
+  NightLightController::RegisterPrefs(user_2_pref_service.registry());
+
+  // Simulate user 1 login.
+  InjectTestPrefService(&user_1_pref_service);
+  SwitchActiveUser(user_1_email);
+  NightLightController* controller = GetController();
+  controller->SetEnabled(true);
+  EXPECT_TRUE(GetController()->enabled());
+  EXPECT_TRUE(TestLayersTemperature(GetController()->color_temperature()));
+
+  // Switch to user 2, and expect NightLight to be disabled.
+  InjectTestPrefService(&user_2_pref_service);
+  SwitchActiveUser(user_2_email);
+  EXPECT_FALSE(controller->enabled());
+
+  // Switch back to user 1, to find NightLight is still enabled.
+  InjectTestPrefService(&user_1_pref_service);
+  SwitchActiveUser(user_1_email);
+  EXPECT_TRUE(controller->enabled());
+}
+
+}  // namespace
+
+}  // namespace ash