[CrOS Tether] Create TetherDisconnector, which disconnects from active tethering sessions.

chromeos/components/tether/tether_disconnector_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 "chromeos/components/tether/tether_disconnector.h"
+
+#include "base/memory/ptr_util.h"
+#include "base/message_loop/message_loop.h"
+#include "chromeos/components/tether/connect_tethering_operation.h"
+#include "chromeos/components/tether/device_id_tether_network_guid_map.h"
+#include "chromeos/components/tether/fake_active_host.h"
+#include "chromeos/components/tether/fake_ble_connection_manager.h"
+#include "chromeos/components/tether/fake_network_configuration_remover.h"
+#include "chromeos/components/tether/fake_tether_host_fetcher.h"
+#include "chromeos/components/tether/fake_wifi_hotspot_connector.h"
+#include "chromeos/components/tether/mock_tether_host_response_recorder.h"
+#include "chromeos/components/tether/tether_connector.h"
+#include "chromeos/dbus/dbus_thread_manager.h"
+#include "chromeos/network/network_connection_handler.h"
+#include "chromeos/network/network_state.h"
+#include "chromeos/network/network_state_handler.h"
+#include "chromeos/network/network_state_test.h"
+#include "components/cryptauth/remote_device.h"
+#include "components/cryptauth/remote_device_test_util.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "third_party/cros_system_api/dbus/shill/dbus-constants.h"
+
+namespace chromeos {
+
+namespace tether {
+
+namespace {
+
+const char kSuccessResult[] = "success";
+
+const char kWifiNetworkGuid[] = "wifiNetworkGuid";
+
+std::string CreateConnectedWifiConfigurationJsonString() {
+  std::stringstream ss;
+  ss << "{"
+     << "  \"GUID\": \"" << kWifiNetworkGuid << "\","
+     << "  \"Type\": \"" << shill::kTypeWifi << "\","
+     << "  \"State\": \"" << shill::kStateOnline << "\""
+     << "}";
+  return ss.str();
+}
+
+class TestNetworkConnectionHandler : public NetworkConnectionHandler {
+ public:
+  TestNetworkConnectionHandler(base::Closure disconnect_callback)
+      : disconnect_callback_(disconnect_callback) {}
+  ~TestNetworkConnectionHandler() override {}
+
+  std::string last_disconnect_service_path() {
+    return last_disconnect_service_path_;
+  }
+
+  base::Closure last_disconnect_success_callback() {
+    return last_disconnect_success_callback_;
+  }
+
+  network_handler::ErrorCallback last_disconnect_error_callback() {
+    return last_disconnect_error_callback_;
+  }
+
+  // NetworkConnectionHandler:
+  void DisconnectNetwork(
+      const std::string& service_path,
+      const base::Closure& success_callback,
+      const network_handler::ErrorCallback& error_callback) override {
+    last_disconnect_service_path_ = service_path;
+    last_disconnect_success_callback_ = success_callback;
+    last_disconnect_error_callback_ = error_callback;
+
+    disconnect_callback_.Run();
+  }
+  void ConnectToNetwork(const std::string& service_path,
+                        const base::Closure& success_callback,
+                        const network_handler::ErrorCallback& error_callback,
+                        bool check_error_state) override {}
+  bool HasConnectingNetwork(const std::string& service_path) override {
+    return false;
+  }
+  bool HasPendingConnectRequest() override { return false; }
+  void Init(NetworkStateHandler* network_state_handler,
+            NetworkConfigurationHandler* network_configuration_handler,
+            ManagedNetworkConfigurationHandler*
+                managed_network_configuration_handler) override {}
+
+ private:
+  base::Closure disconnect_callback_;
+
+  std::string last_disconnect_service_path_;
+  base::Closure last_disconnect_success_callback_;
+  network_handler::ErrorCallback last_disconnect_error_callback_;
+};
+
+class TestTetherConnector : public TetherConnector {
+ public:
+  TestTetherConnector()
+      : TetherConnector(nullptr /* network_state_handler */,
+                        nullptr /* wifi_hotspot_connector */,
+                        nullptr /* active_host */,
+                        nullptr /* tether_host_fetcher */,
+                        nullptr /* connection_manager */,
+                        nullptr /* tether_host_response_recorder */,
+                        nullptr /* device_id_tether_network_guid_map */),
+        should_cancel_successfully_(true) {}
+  ~TestTetherConnector() override {}
+
+  void set_should_cancel_successfully(bool should_cancel_successfully) {
+    should_cancel_successfully_ = should_cancel_successfully;
+  }
+
+  std::string last_canceled_tether_network_guid() {
+    return last_canceled_tether_network_guid_;
+  }
+
+  // TetherConnector:
+  bool CancelConnectionAttempt(
+      const std::string& tether_network_guid) override {
+    last_canceled_tether_network_guid_ = tether_network_guid;
+    return should_cancel_successfully_;
+  }
+
+ private:
+  bool should_cancel_successfully_;
+  std::string last_canceled_tether_network_guid_;
+};
+
+class FakeDisconnectTetheringOperation : public DisconnectTetheringOperation {
+ public:
+  FakeDisconnectTetheringOperation(
+      const cryptauth::RemoteDevice& device_to_connect,
+      BleConnectionManager* connection_manager)
+      : DisconnectTetheringOperation(device_to_connect, connection_manager) {}
+
+  ~FakeDisconnectTetheringOperation() override {}
+
+  void NotifyFinished(bool success) {
+    NotifyObserversOperationFinished(success);
+  }
+
+  cryptauth::RemoteDevice GetRemoteDevice() {
+    EXPECT_EQ(1u, remote_devices().size());
+    return remote_devices()[0];
+  }
+};
+
+class FakeDisconnectTetheringOperationFactory
+    : public DisconnectTetheringOperation::Factory {
+ public:
+  FakeDisconnectTetheringOperationFactory() {}
+  virtual ~FakeDisconnectTetheringOperationFactory() {}
+
+  std::vector<FakeDisconnectTetheringOperation*>& created_operations() {
+    return created_operations_;
+  }
+
+ protected:
+  // DisconnectTetheringOperation::Factory:
+  std::unique_ptr<DisconnectTetheringOperation> BuildInstance(
+      const cryptauth::RemoteDevice& device_to_connect,
+      BleConnectionManager* connection_manager) override {
+    FakeDisconnectTetheringOperation* operation =
+        new FakeDisconnectTetheringOperation(device_to_connect,
+                                             connection_manager);
+    created_operations_.push_back(operation);
+    return base::WrapUnique(operation);
+  }
+
+ private:
+  std::vector<FakeDisconnectTetheringOperation*> created_operations_;
+};
+
+}  // namespace
+
+class TetherDisconnectorTest : public NetworkStateTest {
+ public:
+  TetherDisconnectorTest()
+      : test_devices_(cryptauth::GenerateTestRemoteDevices(2u)) {}
+  ~TetherDisconnectorTest() override {}
+
+  void SetUp() override {
+    DBusThreadManager::Initialize();
+    NetworkStateTest::SetUp();
+
+    should_disconnect_successfully_ = true;
+
+    test_network_connection_handler_ =
+        base::WrapUnique(new TestNetworkConnectionHandler(base::Bind(
+            &TetherDisconnectorTest::OnNetworkConnectionManagerDisconnect,
+            base::Unretained(this))));
+    fake_active_host_ = base::MakeUnique<FakeActiveHost>();
+    fake_ble_connection_manager_ = base::MakeUnique<FakeBleConnectionManager>();
+    fake_network_configuration_remover_ =
+        base::MakeUnique<FakeNetworkConfigurationRemover>();
+    test_tether_connector_ = base::WrapUnique(new TestTetherConnector());
+    device_id_tether_network_guid_map_ =
+        base::MakeUnique<DeviceIdTetherNetworkGuidMap>();
+    fake_tether_host_fetcher_ = base::MakeUnique<FakeTetherHostFetcher>(
+        test_devices_, true /* synchronously_reply_with_results */);
+
+    fake_operation_factory_ =
+        base::WrapUnique(new FakeDisconnectTetheringOperationFactory());
+    DisconnectTetheringOperation::Factory::SetInstanceForTesting(
+        fake_operation_factory_.get());
+
+    SetUpTetherNetworks();
+
+    tether_disconnector_ = base::MakeUnique<TetherDisconnector>(
+        test_network_connection_handler_.get(), network_state_handler(),
+        fake_active_host_.get(), fake_ble_connection_manager_.get(),
+        fake_network_configuration_remover_.get(), test_tether_connector_.get(),
+        device_id_tether_network_guid_map_.get(),
+        fake_tether_host_fetcher_.get());
+  }
+
+  void TearDown() override {
+    ShutdownNetworkState();
+    NetworkStateTest::TearDown();
+    DBusThreadManager::Shutdown();
+  }
+
+  std::string GetTetherNetworkGuid(const std::string& device_id) {
+    return device_id_tether_network_guid_map_->GetTetherNetworkGuidForDeviceId(
+        device_id);
+  }
+
+  void SetUpTetherNetworks() {
+    network_state_handler()->SetTetherTechnologyState(
+        NetworkStateHandler::TECHNOLOGY_ENABLED);
+
+    // Add a tether network corresponding to both of the test devices. These
+    // networks are expected to be added already before
+    // TetherDisconnector::DisconnectFromNetwork() is called.
+    network_state_handler()->AddTetherNetworkState(
+        GetTetherNetworkGuid(test_devices_[0].GetDeviceId()),
+        "TetherNetworkName1", "TetherNetworkCarrier1",
+        85 /* battery_percentage */, 75 /* signal_strength */,
+        true /* has_connected_to_host */);
+    network_state_handler()->AddTetherNetworkState(
+        GetTetherNetworkGuid(test_devices_[1].GetDeviceId()),
+        "TetherNetworkName2", "TetherNetworkCarrier2",
+        90 /* battery_percentage */, 50 /* signal_strength */,
+        true /* has_connected_to_host */);
+  }
+
+  void SimulateConnectionToWifiNetwork() {
+    wifi_service_path_ =
+        ConfigureService(CreateConnectedWifiConfigurationJsonString());
+    EXPECT_FALSE(wifi_service_path_.empty());
+  }
+
+  void SuccessCallback() { disconnection_result_ = kSuccessResult; }
+
+  void ErrorCallback(const std::string& error_name) {
+    disconnection_result_ = error_name;
+  }
+
+  void CallDisconnect(const std::string& tether_network_guid) {
+    tether_disconnector_->DisconnectFromNetwork(
+        tether_network_guid,
+        base::Bind(&TetherDisconnectorTest::SuccessCallback,
+                   base::Unretained(this)),
+        base::Bind(&TetherDisconnectorTest::ErrorCallback,
+                   base::Unretained(this)));
+  }
+
+  // This function is called by
+  // TestNetworkConnectionHandler::DisconnectFromNetwork().
+  void OnNetworkConnectionManagerDisconnect() {
+    EXPECT_EQ(wifi_service_path_,
+              test_network_connection_handler_->last_disconnect_service_path());
+
+    if (should_disconnect_successfully_) {
+      SetServiceProperty(wifi_service_path_, shill::kStateProperty,
+                         base::Value(shill::kStateIdle));
+      EXPECT_FALSE(
+          test_network_connection_handler_->last_disconnect_success_callback()
+              .is_null());
+      test_network_connection_handler_->last_disconnect_success_callback()
+          .Run();
+    } else {
+      EXPECT_FALSE(
+          test_network_connection_handler_->last_disconnect_error_callback()
+              .is_null());
+      network_handler::RunErrorCallback(
+          test_network_connection_handler_->last_disconnect_error_callback(),
+          wifi_service_path_, NetworkConnectionHandler::kErrorDisconnectFailed,
+          "" /* error_detail */);
+    }
+  }
+
+  std::string GetResultAndReset() {
+    std::string result;
+    result.swap(disconnection_result_);
+    return result;
+  }
+
+  const std::vector<cryptauth::RemoteDevice> test_devices_;
+  const base::MessageLoop message_loop_;
+
+  std::unique_ptr<TestNetworkConnectionHandler>
+      test_network_connection_handler_;
+  std::unique_ptr<FakeActiveHost> fake_active_host_;
+  std::unique_ptr<FakeBleConnectionManager> fake_ble_connection_manager_;
+  std::unique_ptr<FakeNetworkConfigurationRemover>
+      fake_network_configuration_remover_;
+  std::unique_ptr<TestTetherConnector> test_tether_connector_;
+  // TODO(hansberry): Use a fake for this when a real mapping scheme is created.
+  std::unique_ptr<DeviceIdTetherNetworkGuidMap>
+      device_id_tether_network_guid_map_;
+  std::unique_ptr<FakeTetherHostFetcher> fake_tether_host_fetcher_;
+
+  std::unique_ptr<FakeDisconnectTetheringOperationFactory>
+      fake_operation_factory_;
+
+  std::string wifi_service_path_;
+  std::string disconnection_result_;
+  bool should_disconnect_successfully_;
+
+  std::unique_ptr<TetherDisconnector> tether_disconnector_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(TetherDisconnectorTest);
+};
+
+TEST_F(TetherDisconnectorTest, DisconnectWhenAlreadyDisconnected) {
+  CallDisconnect(GetTetherNetworkGuid(test_devices_[0].GetDeviceId()));
+  EXPECT_EQ(NetworkConnectionHandler::kErrorNotConnected, GetResultAndReset());
+
+  // Should still be disconnected.
+  EXPECT_EQ(ActiveHost::ActiveHostStatus::DISCONNECTED,
+            fake_active_host_->GetActiveHostStatus());
+}
+
+TEST_F(TetherDisconnectorTest, DisconnectWhenOtherDeviceConnected) {
+  fake_active_host_->SetActiveHostConnected(
+      test_devices_[1].GetDeviceId(),
+      GetTetherNetworkGuid(test_devices_[1].GetDeviceId()),
+      "otherWifiNetworkGuid");
+
+  CallDisconnect(GetTetherNetworkGuid(test_devices_[0].GetDeviceId()));
+  EXPECT_EQ(NetworkConnectionHandler::kErrorNotConnected, GetResultAndReset());
+
+  // Should still be connected to the other host.
+  EXPECT_EQ(ActiveHost::ActiveHostStatus::CONNECTED,
+            fake_active_host_->GetActiveHostStatus());
+  EXPECT_EQ(test_devices_[1].GetDeviceId(),
+            fake_active_host_->GetActiveHostDeviceId());
+}
+
+TEST_F(TetherDisconnectorTest, DisconnectWhenConnecting_CancelFails) {
+  fake_active_host_->SetActiveHostConnecting(
+      test_devices_[0].GetDeviceId(),
+      GetTetherNetworkGuid(test_devices_[0].GetDeviceId()));
+  test_tether_connector_->set_should_cancel_successfully(false);
+
+  CallDisconnect(GetTetherNetworkGuid(test_devices_[0].GetDeviceId()));
+  EXPECT_EQ(NetworkConnectionHandler::kErrorDisconnectFailed,
+            GetResultAndReset());
+  EXPECT_EQ(GetTetherNetworkGuid(test_devices_[0].GetDeviceId()),
+            test_tether_connector_->last_canceled_tether_network_guid());
+
+  // Note: This test does not check the active host's status because it will be
+  // changed by TetherConnector.
+}
+
+TEST_F(TetherDisconnectorTest, DisconnectWhenConnecting_CancelSucceeds) {
+  fake_active_host_->SetActiveHostConnecting(
+      test_devices_[0].GetDeviceId(),
+      GetTetherNetworkGuid(test_devices_[0].GetDeviceId()));
+  test_tether_connector_->set_should_cancel_successfully(true);
+
+  CallDisconnect(GetTetherNetworkGuid(test_devices_[0].GetDeviceId()));
+  EXPECT_EQ(kSuccessResult, GetResultAndReset());
+  EXPECT_EQ(GetTetherNetworkGuid(test_devices_[0].GetDeviceId()),
+            test_tether_connector_->last_canceled_tether_network_guid());
+
+  // Note: This test does not check the active host's status because it will be
+  // changed by TetherConnector.
+}
+
+TEST_F(TetherDisconnectorTest, DisconnectWhenConnected_NotActuallyConnected) {
+  fake_active_host_->SetActiveHostConnected(
+      test_devices_[0].GetDeviceId(),
+      GetTetherNetworkGuid(test_devices_[0].GetDeviceId()),
+      "nonExistentWifiGuid");
+
+  CallDisconnect(GetTetherNetworkGuid(test_devices_[0].GetDeviceId()));
+  EXPECT_EQ(NetworkConnectionHandler::kErrorDisconnectFailed,
+            GetResultAndReset());
+
+  // Should be disconnected.
+  EXPECT_EQ(ActiveHost::ActiveHostStatus::DISCONNECTED,
+            fake_active_host_->GetActiveHostStatus());
+}
+
+TEST_F(TetherDisconnectorTest,
+       DisconnectWhenConnected_WifiConnectionFails_CannotFetchHost) {
+  fake_active_host_->SetActiveHostConnected(
+      test_devices_[0].GetDeviceId(),
+      GetTetherNetworkGuid(test_devices_[0].GetDeviceId()), kWifiNetworkGuid);
+  SimulateConnectionToWifiNetwork();
+
+  // Remove hosts from |fake_tether_host_fetcher_|; this will cause the fetcher
+  // to return a null RemoteDevice.
+  fake_tether_host_fetcher_->SetTetherHosts(
+      std::vector<cryptauth::RemoteDevice>());
+
+  should_disconnect_successfully_ = false;
+
+  CallDisconnect(GetTetherNetworkGuid(test_devices_[0].GetDeviceId()));
+  EXPECT_EQ(NetworkConnectionHandler::kErrorDisconnectFailed,
+            GetResultAndReset());
+
+  // The Wi-Fi network should still be connected since disconnection failed.
+  EXPECT_EQ(
+      shill::kStateOnline,
+      GetServiceStringProperty(wifi_service_path_, shill::kStateProperty));
+
+  // Should not have created any operations since the fetch failed.
+  EXPECT_TRUE(fake_operation_factory_->created_operations().empty());
+
+  // Should be disconnected.
+  EXPECT_EQ(ActiveHost::ActiveHostStatus::DISCONNECTED,
+            fake_active_host_->GetActiveHostStatus());
+}
+
+TEST_F(TetherDisconnectorTest,
+       DisconnectWhenConnected_WifiConnectionSucceeds_CannotFetchHost) {
+  fake_active_host_->SetActiveHostConnected(
+      test_devices_[0].GetDeviceId(),
+      GetTetherNetworkGuid(test_devices_[0].GetDeviceId()), kWifiNetworkGuid);
+  SimulateConnectionToWifiNetwork();
+
+  // Remove hosts from |fake_tether_host_fetcher_|; this will cause the fetcher
+  // to return a null RemoteDevice.
+  fake_tether_host_fetcher_->SetTetherHosts(
+      std::vector<cryptauth::RemoteDevice>());
+
+  CallDisconnect(GetTetherNetworkGuid(test_devices_[0].GetDeviceId()));
+  EXPECT_EQ(kSuccessResult, GetResultAndReset());
+
+  // The Wi-Fi network should be disconnected since disconnection failed.
+  EXPECT_EQ(shill::kStateIdle, GetServiceStringProperty(wifi_service_path_,
+                                                        shill::kStateProperty));
+
+  // Should not have created any operations since the fetch failed.
+  EXPECT_TRUE(fake_operation_factory_->created_operations().empty());
+
+  // Should be disconnected.
+  EXPECT_EQ(ActiveHost::ActiveHostStatus::DISCONNECTED,
+            fake_active_host_->GetActiveHostStatus());
+}
+
+TEST_F(TetherDisconnectorTest,
+       DisconnectWhenConnected_WifiConnectionFails_OperationFails) {
+  fake_active_host_->SetActiveHostConnected(
+      test_devices_[0].GetDeviceId(),
+      GetTetherNetworkGuid(test_devices_[0].GetDeviceId()), kWifiNetworkGuid);
+  SimulateConnectionToWifiNetwork();
+
+  should_disconnect_successfully_ = false;
+
+  CallDisconnect(GetTetherNetworkGuid(test_devices_[0].GetDeviceId()));
+  EXPECT_EQ(NetworkConnectionHandler::kErrorDisconnectFailed,
+            GetResultAndReset());
+
+  // The Wi-Fi network should still be connected since disconnection failed.
+  EXPECT_EQ(
+      shill::kStateOnline,
+      GetServiceStringProperty(wifi_service_path_, shill::kStateProperty));
+
+  // Fail the operation.
+  ASSERT_EQ(1u, fake_operation_factory_->created_operations().size());
+  EXPECT_EQ(
+      test_devices_[0],
+      fake_operation_factory_->created_operations()[0]->GetRemoteDevice());
+  fake_operation_factory_->created_operations()[0]->NotifyFinished(
+      false /* success */);
+
+  // Should be disconnected.
+  EXPECT_EQ(ActiveHost::ActiveHostStatus::DISCONNECTED,
+            fake_active_host_->GetActiveHostStatus());
+}
+
+TEST_F(TetherDisconnectorTest,
+       DisconnectWhenConnected_WifiConnectionSucceeds_OperationFails) {
+  fake_active_host_->SetActiveHostConnected(
+      test_devices_[0].GetDeviceId(),
+      GetTetherNetworkGuid(test_devices_[0].GetDeviceId()), kWifiNetworkGuid);
+  SimulateConnectionToWifiNetwork();
+
+  CallDisconnect(GetTetherNetworkGuid(test_devices_[0].GetDeviceId()));
+  EXPECT_EQ(kSuccessResult, GetResultAndReset());
+
+  // The Wi-Fi network should be disconnected since disconnection failed.
+  EXPECT_EQ(shill::kStateIdle, GetServiceStringProperty(wifi_service_path_,
+                                                        shill::kStateProperty));
+
+  ASSERT_EQ(1u, fake_operation_factory_->created_operations().size());
+  EXPECT_EQ(
+      test_devices_[0],
+      fake_operation_factory_->created_operations()[0]->GetRemoteDevice());
+  fake_operation_factory_->created_operations()[0]->NotifyFinished(
+      false /* success */);
+
+  // Should be disconnected.
+  EXPECT_EQ(ActiveHost::ActiveHostStatus::DISCONNECTED,
+            fake_active_host_->GetActiveHostStatus());
+}
+
+TEST_F(TetherDisconnectorTest,
+       DisconnectWhenConnected_WifiConnectionFails_OperationSucceeds) {
+  fake_active_host_->SetActiveHostConnected(
+      test_devices_[0].GetDeviceId(),
+      GetTetherNetworkGuid(test_devices_[0].GetDeviceId()), kWifiNetworkGuid);
+  SimulateConnectionToWifiNetwork();
+
+  should_disconnect_successfully_ = false;
+
+  CallDisconnect(GetTetherNetworkGuid(test_devices_[0].GetDeviceId()));
+  EXPECT_EQ(NetworkConnectionHandler::kErrorDisconnectFailed,
+            GetResultAndReset());
+
+  // The Wi-Fi network should still be connected since disconnection failed.
+  EXPECT_EQ(
+      shill::kStateOnline,
+      GetServiceStringProperty(wifi_service_path_, shill::kStateProperty));
+
+  // Fail the operation.
+  ASSERT_EQ(1u, fake_operation_factory_->created_operations().size());
+  EXPECT_EQ(
+      test_devices_[0],
+      fake_operation_factory_->created_operations()[0]->GetRemoteDevice());
+  fake_operation_factory_->created_operations()[0]->NotifyFinished(
+      true /* success */);
+
+  // Should be disconnected.
+  EXPECT_EQ(ActiveHost::ActiveHostStatus::DISCONNECTED,
+            fake_active_host_->GetActiveHostStatus());
+}
+
+TEST_F(TetherDisconnectorTest,
+       DisconnectWhenConnected_WifiConnectionSucceeds_OperationSucceeds) {
+  fake_active_host_->SetActiveHostConnected(
+      test_devices_[0].GetDeviceId(),
+      GetTetherNetworkGuid(test_devices_[0].GetDeviceId()), kWifiNetworkGuid);
+  SimulateConnectionToWifiNetwork();
+
+  CallDisconnect(GetTetherNetworkGuid(test_devices_[0].GetDeviceId()));
+  EXPECT_EQ(kSuccessResult, GetResultAndReset());
+
+  // The Wi-Fi network should be disconnected since disconnection failed.
+  EXPECT_EQ(shill::kStateIdle, GetServiceStringProperty(wifi_service_path_,
+                                                        shill::kStateProperty));
+
+  ASSERT_EQ(1u, fake_operation_factory_->created_operations().size());
+  EXPECT_EQ(
+      test_devices_[0],
+      fake_operation_factory_->created_operations()[0]->GetRemoteDevice());
+  fake_operation_factory_->created_operations()[0]->NotifyFinished(
+      true /* success */);
+
+  // Should be disconnected.
+  EXPECT_EQ(ActiveHost::ActiveHostStatus::DISCONNECTED,
+            fake_active_host_->GetActiveHostStatus());
+}
+
+TEST_F(TetherDisconnectorTest,
+       DisconnectWhenConnected_DestroyBeforeOperationComplete) {
+  fake_active_host_->SetActiveHostConnected(
+      test_devices_[0].GetDeviceId(),
+      GetTetherNetworkGuid(test_devices_[0].GetDeviceId()), kWifiNetworkGuid);
+  SimulateConnectionToWifiNetwork();
+
+  CallDisconnect(GetTetherNetworkGuid(test_devices_[0].GetDeviceId()));
+  EXPECT_EQ(kSuccessResult, GetResultAndReset());
+
+  // Stop the test here, before the operation responds in any way. This test
+  // ensures that TetherDisconnector properly removes existing listeners if it
+  // is destroyed while there are still active operations.
+}
+
+}  // namespace tether
+
+}  // namespace chromeos