[CrOS Tether] Sort Tether network lists.

chromeos/network/network_state_handler_unittest.cc

Index: chromeos/network/network_state_handler_unittest.cc
diff --git a/chromeos/network/network_state_handler_unittest.cc b/chromeos/network/network_state_handler_unittest.cc
index e6c467c07b8a882bb6828566f816e73655e6668f..ecd130d5e8112e5916154c9da75e7e1e95560312 100644
--- a/chromeos/network/network_state_handler_unittest.cc
+++ b/chromeos/network/network_state_handler_unittest.cc
@@ -6,6 +6,7 @@
 
 #include <stddef.h>
 
+#include <algorithm>
 #include <map>
 #include <memory>
 #include <set>
@@ -33,6 +34,8 @@
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/cros_system_api/dbus/service_constants.h"
 
+namespace chromeos {
+
 namespace {
 
 void ErrorCallbackFunction(const std::string& error_name,
@@ -199,9 +202,33 @@ class TestObserver : public chromeos::NetworkStateHandlerObserver {
   DISALLOW_COPY_AND_ASSIGN(TestObserver);
 };
 
-}  // namespace
+class TestTetherNetworkListSorter
+    : public NetworkStateHandler::TetherNetworkListSorter {
+ public:
+  TestTetherNetworkListSorter() {}
+  ~TestTetherNetworkListSorter() {}
+
+  // NetworkStateHandler::TetherNetworkListSorter:
+  void SortTetherNetworkList(
+      NetworkStateHandler::ManagedStateList* tether_networks) const override {
+    std::sort(tether_networks->begin(), tether_networks->end(),
+              [](const std::unique_ptr<ManagedState>& first,
+                 const std::unique_ptr<ManagedState>& second) {
+                const NetworkState* first_network =
+                    static_cast<const NetworkState*>(first.get());
+                const NetworkState* second_network =
+                    static_cast<const NetworkState*>(second.get());
+
+                // Sort by reverse-alphabetical order of GUIDs.
+                return first_network->guid() >= second_network->guid();
+              });
+  }
 
-namespace chromeos {
+ private:
+  DISALLOW_COPY_AND_ASSIGN(TestTetherNetworkListSorter);
+};
+
+}  // namespace
 
 class NetworkStateHandlerTest : public testing::Test {
  public:
@@ -463,6 +490,55 @@ TEST_F(NetworkStateHandlerTest, GetTetherNetworkList) {
   EXPECT_EQ(1u, tether_networks.size());
 }
 
+TEST_F(NetworkStateHandlerTest, SortTetherNetworkList) {
+  network_state_handler_->SetTetherTechnologyState(
+      NetworkStateHandler::TECHNOLOGY_ENABLED);
+
+  TestTetherNetworkListSorter sorter;
+  network_state_handler_->SetTetherNetworkListSorter(&sorter);
+
+  network_state_handler_->AddTetherNetworkState(
+      kTetherGuid1, kTetherName1, kTetherCarrier1, kTetherBatteryPercentage1,
+      kTetherSignalStrength1, kTetherHasConnectedToHost1);
+  network_state_handler_->AddTetherNetworkState(
+      kTetherGuid2, kTetherName2, kTetherCarrier2, kTetherBatteryPercentage2,
+      kTetherSignalStrength2, kTetherHasConnectedToHost2);
+
+  // Note: GetVisibleNetworkListByType() sorts before outputting networks.
+  NetworkStateHandler::NetworkStateList tether_networks;
+  network_state_handler_->GetVisibleNetworkListByType(
+      NetworkTypePattern::Tether(), &tether_networks);
+
+  // The list should have been reversed due to reverse-alphabetical sorting.
+  EXPECT_EQ(2u, tether_networks.size());
+  EXPECT_EQ(kTetherGuid2, tether_networks[0]->guid());
+  EXPECT_EQ(kTetherGuid1, tether_networks[1]->guid());
+}
+
+TEST_F(NetworkStateHandlerTest, SortTetherNetworkList_NoSortingDelegate) {
+  network_state_handler_->SetTetherTechnologyState(
+      NetworkStateHandler::TECHNOLOGY_ENABLED);
+
+  // Do not set a TetherNetworkListSorter.
+
+  network_state_handler_->AddTetherNetworkState(
+      kTetherGuid1, kTetherName1, kTetherCarrier1, kTetherBatteryPercentage1,
+      kTetherSignalStrength1, kTetherHasConnectedToHost1);
+  network_state_handler_->AddTetherNetworkState(
+      kTetherGuid2, kTetherName2, kTetherCarrier2, kTetherBatteryPercentage2,
+      kTetherSignalStrength2, kTetherHasConnectedToHost2);
+
+  // Note: GetVisibleNetworkListByType() sorts before outputting networks.
+  NetworkStateHandler::NetworkStateList tether_networks;
+  network_state_handler_->GetVisibleNetworkListByType(
+      NetworkTypePattern::Tether(), &tether_networks);
+
+  // The list should be in the original order.
+  EXPECT_EQ(2u, tether_networks.size());
+  EXPECT_EQ(kTetherGuid1, tether_networks[0]->guid());
+  EXPECT_EQ(kTetherGuid2, tether_networks[1]->guid());
+}
+
 TEST_F(NetworkStateHandlerTest, NetworkListChanged) {
   size_t stub_network_count = test_observer_->network_count();
   // Set up two additional visible networks.