content/browser/geolocation/network_location_provider_unittest.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "base/json/json_reader.h"
   6 #include "base/json/json_writer.h"
   7 #include "base/memory/scoped_ptr.h"
   8 #include "base/strings/string_number_conversions.h"
   9 #include "base/strings/string_util.h"
  10 #include "base/strings/stringprintf.h"
  11 #include "base/strings/utf_string_conversions.h"
  12 #include "base/values.h"
  13 #include "content/browser/geolocation/fake_access_token_store.h"
  14 #include "content/browser/geolocation/location_arbitrator_impl.h"
  15 #include "content/browser/geolocation/network_location_provider.h"
  16 #include "net/url_request/test_url_fetcher_factory.h"
  17 #include "net/url_request/url_request_status.h"
  18 #include "testing/gtest/include/gtest/gtest.h"
  19
  20 namespace content {
  21
  22 // Constants used in multiple tests.
  23 const char kTestServerUrl[] = "https://www.geolocation.test/service";
  24 const char kAccessTokenString[] = "accessToken";
  25
  26 // Using #define so we can easily paste this into various other strings.
  27 #define REFERENCE_ACCESS_TOKEN "2:k7j3G6LaL6u_lafw:4iXOeOpTh1glSXe"
  28
  29 // Stops the specified (nested) message loop when the listener is called back.
  30 class MessageLoopQuitListener {
  31  public:
  32   MessageLoopQuitListener()
  33       : client_message_loop_(base::MessageLoop::current()),
  34         updated_provider_(NULL) {
  35     CHECK(client_message_loop_);
  36   }
  37
  38   void LocationUpdateAvailable(const LocationProvider* provider,
  39                                const Geoposition& position) {
  40     EXPECT_EQ(client_message_loop_, base::MessageLoop::current());
  41     updated_provider_ = provider;
  42     client_message_loop_->Quit();
  43   }
  44
  45   base::MessageLoop* client_message_loop_;
  46   const LocationProvider* updated_provider_;
  47 };
  48
  49 // A mock implementation of WifiDataProviderImplBase for testing. Adapted from
  50 // http://gears.googlecode.com/svn/trunk/gears/geolocation/geolocation_test.cc
  51 class MockWifiDataProviderImpl : public WifiDataProviderImplBase {
  52  public:
  53   // Factory method for use with WifiDataProvider::SetFactory.
  54   static WifiDataProviderImplBase* GetInstance() {
  55     CHECK(instance_);
  56     return instance_;
  57   }
  58
  59   static MockWifiDataProviderImpl* CreateInstance() {
  60     CHECK(!instance_);
  61     instance_ = new MockWifiDataProviderImpl;
  62     return instance_;
  63   }
  64
  65   MockWifiDataProviderImpl()
  66       : start_calls_(0),
  67         stop_calls_(0),
  68         got_data_(true) {
  69   }
  70
  71   // WifiDataProviderImplBase implementation.
  72   virtual void StartDataProvider() OVERRIDE {
  73     ++start_calls_;
  74   }
  75
  76   virtual void StopDataProvider() OVERRIDE {
  77     ++stop_calls_;
  78   }
  79
  80   virtual bool GetData(WifiData* data_out) OVERRIDE {
  81     CHECK(data_out);
  82     *data_out = data_;
  83     return got_data_;
  84   }
  85
  86   void SetData(const WifiData& new_data) {
  87     got_data_ = true;
  88     const bool differs = data_.DiffersSignificantly(new_data);
  89     data_ = new_data;
  90     if (differs)
  91       this->RunCallbacks();
  92   }
  93
  94   void set_got_data(bool got_data) { got_data_ = got_data; }
  95   int start_calls_;
  96   int stop_calls_;
  97
  98  private:
  99   virtual ~MockWifiDataProviderImpl() {
 100     CHECK(this == instance_);
 101     instance_ = NULL;
 102   }
 103
 104   static MockWifiDataProviderImpl* instance_;
 105
 106   WifiData data_;
 107   bool got_data_;
 108
 109   DISALLOW_COPY_AND_ASSIGN(MockWifiDataProviderImpl);
 110 };
 111
 112 MockWifiDataProviderImpl* MockWifiDataProviderImpl::instance_ = NULL;
 113
 114 // Main test fixture
 115 class GeolocationNetworkProviderTest : public testing::Test {
 116  public:
 117   virtual void SetUp() {
 118     test_server_url_ = GURL(kTestServerUrl);
 119     access_token_store_ = new FakeAccessTokenStore;
 120     wifi_data_provider_ =
 121         MockWifiDataProviderImpl::CreateInstance();
 122   }
 123
 124   virtual void TearDown() {
 125     WifiDataProvider::ResetFactory();
 126   }
 127
 128   LocationProvider* CreateProvider(bool set_permission_granted) {
 129     LocationProvider* provider = NewNetworkLocationProvider(
 130         access_token_store_.get(),
 131         NULL,  // No URLContextGetter needed, as using test urlfecther factory.
 132         test_server_url_,
 133         access_token_store_->access_token_set_[test_server_url_]);
 134     if (set_permission_granted)
 135       provider->OnPermissionGranted();
 136     return provider;
 137   }
 138
 139  protected:
 140   GeolocationNetworkProviderTest() {
 141     // TODO(joth): Really these should be in SetUp, not here, but they take no
 142     // effect on Mac OS Release builds if done there. I kid not. Figure out why.
 143     WifiDataProvider::SetFactory(MockWifiDataProviderImpl::GetInstance);
 144   }
 145
 146   // Returns the current url fetcher (if any) and advances the id ready for the
 147   // next test step.
 148   net::TestURLFetcher* get_url_fetcher_and_advance_id() {
 149     net::TestURLFetcher* fetcher = url_fetcher_factory_.GetFetcherByID(
 150             NetworkLocationRequest::url_fetcher_id_for_tests);
 151     if (fetcher)
 152       ++NetworkLocationRequest::url_fetcher_id_for_tests;
 153     return fetcher;
 154   }
 155
 156   static int IndexToChannel(int index) { return index + 4; }
 157
 158   // Creates wifi data containing the specified number of access points, with
 159   // some differentiating charactistics in each.
 160   static WifiData CreateReferenceWifiScanData(int ap_count) {
 161     WifiData data;
 162     for (int i = 0; i < ap_count; ++i) {
 163       AccessPointData ap;
 164       ap.mac_address =
 165           base::ASCIIToUTF16(base::StringPrintf("%02d-34-56-78-54-32", i));
 166       ap.radio_signal_strength = ap_count - i;
 167       ap.channel = IndexToChannel(i);
 168       ap.signal_to_noise = i + 42;
 169       ap.ssid = base::ASCIIToUTF16("Some nice+network|name\\");
 170       data.access_point_data.insert(ap);
 171     }
 172     return data;
 173   }
 174
 175   static void CreateReferenceWifiScanDataJson(
 176       int ap_count, int start_index, base::ListValue* wifi_access_point_list) {
 177     std::vector<std::string> wifi_data;
 178     for (int i = 0; i < ap_count; ++i) {
 179       base::DictionaryValue* ap = new base::DictionaryValue();
 180       ap->SetString("macAddress", base::StringPrintf("%02d-34-56-78-54-32", i));
 181       ap->SetInteger("signalStrength", start_index + ap_count - i);
 182       ap->SetInteger("age", 0);
 183       ap->SetInteger("channel", IndexToChannel(i));
 184       ap->SetInteger("signalToNoiseRatio", i + 42);
 185       wifi_access_point_list->Append(ap);
 186     }
 187   }
 188
 189   static Geoposition CreateReferencePosition(int id) {
 190     Geoposition pos;
 191     pos.latitude = id;
 192     pos.longitude = -(id + 1);
 193     pos.altitude = 2 * id;
 194     pos.timestamp = base::Time::Now();
 195     return pos;
 196   }
 197
 198   static std::string PrettyJson(const base::Value& value) {
 199     std::string pretty;
 200     base::JSONWriter::WriteWithOptions(
 201         &value, base::JSONWriter::OPTIONS_PRETTY_PRINT, &pretty);
 202     return pretty;
 203   }
 204
 205   static testing::AssertionResult JsonGetList(
 206       const std::string& field,
 207       const base::DictionaryValue& dict,
 208       const base::ListValue** output_list) {
 209     if (!dict.GetList(field, output_list))
 210       return testing::AssertionFailure() << "Dictionary " << PrettyJson(dict)
 211                                          << " is missing list field " << field;
 212     return testing::AssertionSuccess();
 213   }
 214
 215   static testing::AssertionResult JsonFieldEquals(
 216       const std::string& field,
 217       const base::DictionaryValue& expected,
 218       const base::DictionaryValue& actual) {
 219     const base::Value* expected_value;
 220     const base::Value* actual_value;
 221     if (!expected.Get(field, &expected_value))
 222       return testing::AssertionFailure()
 223           << "Expected dictionary " << PrettyJson(expected)
 224           << " is missing field " << field;
 225     if (!expected.Get(field, &actual_value))
 226       return testing::AssertionFailure()
 227           << "Actual dictionary " << PrettyJson(actual)
 228           << " is missing field " << field;
 229     if (!expected_value->Equals(actual_value))
 230       return testing::AssertionFailure()
 231           << "Field " << field << " mismatch: " << PrettyJson(*expected_value)
 232           << " != " << PrettyJson(*actual_value);
 233     return testing::AssertionSuccess();
 234   }
 235
 236   static GURL UrlWithoutQuery(const GURL& url) {
 237     url_canon::Replacements<char> replacements;
 238     replacements.ClearQuery();
 239     return url.ReplaceComponents(replacements);
 240   }
 241
 242   testing::AssertionResult IsTestServerUrl(const GURL& request_url) {
 243     const GURL a(UrlWithoutQuery(test_server_url_));
 244     const GURL b(UrlWithoutQuery(request_url));
 245     if (a == b)
 246       return testing::AssertionSuccess();
 247     return testing::AssertionFailure() << a << " != " << b;
 248   }
 249
 250   void CheckRequestIsValid(const net::TestURLFetcher& request,
 251                            int expected_routers,
 252                            int expected_wifi_aps,
 253                            int wifi_start_index,
 254                            const std::string& expected_access_token) {
 255     const GURL& request_url = request.GetOriginalURL();
 256
 257     EXPECT_TRUE(IsTestServerUrl(request_url));
 258
 259     // Check to see that the api key is being appended for the default
 260     // network provider url.
 261     bool is_default_url = UrlWithoutQuery(request_url) ==
 262         UrlWithoutQuery(LocationArbitratorImpl::DefaultNetworkProviderURL());
 263     EXPECT_EQ(is_default_url, !request_url.query().empty());
 264
 265     const std::string& upload_data = request.upload_data();
 266     ASSERT_FALSE(upload_data.empty());
 267     std::string json_parse_error_msg;
 268     scoped_ptr<base::Value> parsed_json(
 269         base::JSONReader::ReadAndReturnError(
 270             upload_data,
 271             base::JSON_PARSE_RFC,
 272             NULL,
 273             &json_parse_error_msg));
 274     EXPECT_TRUE(json_parse_error_msg.empty());
 275     ASSERT_TRUE(parsed_json.get() != NULL);
 276
 277     const base::DictionaryValue* request_json;
 278     ASSERT_TRUE(parsed_json->GetAsDictionary(&request_json));
 279
 280     if (!is_default_url) {
 281       if (expected_access_token.empty())
 282         ASSERT_FALSE(request_json->HasKey(kAccessTokenString));
 283       else {
 284         std::string access_token;
 285         EXPECT_TRUE(request_json->GetString(kAccessTokenString, &access_token));
 286         EXPECT_EQ(expected_access_token, access_token);
 287       }
 288     }
 289
 290     if (expected_wifi_aps) {
 291       base::ListValue expected_wifi_aps_json;
 292       CreateReferenceWifiScanDataJson(
 293           expected_wifi_aps,
 294           wifi_start_index,
 295           &expected_wifi_aps_json);
 296       EXPECT_EQ(size_t(expected_wifi_aps), expected_wifi_aps_json.GetSize());
 297
 298       const base::ListValue* wifi_aps_json;
 299       ASSERT_TRUE(JsonGetList("wifiAccessPoints", *request_json,
 300                               &wifi_aps_json));
 301       for (size_t i = 0; i < expected_wifi_aps_json.GetSize(); ++i ) {
 302         const base::DictionaryValue* expected_json;
 303         ASSERT_TRUE(expected_wifi_aps_json.GetDictionary(i, &expected_json));
 304         const base::DictionaryValue* actual_json;
 305         ASSERT_TRUE(wifi_aps_json->GetDictionary(i, &actual_json));
 306         ASSERT_TRUE(JsonFieldEquals("macAddress", *expected_json,
 307                                     *actual_json));
 308         ASSERT_TRUE(JsonFieldEquals("signalStrength", *expected_json,
 309                                     *actual_json));
 310         ASSERT_TRUE(JsonFieldEquals("channel", *expected_json, *actual_json));
 311         ASSERT_TRUE(JsonFieldEquals("signalToNoiseRatio", *expected_json,
 312                                     *actual_json));
 313       }
 314     } else {
 315       ASSERT_FALSE(request_json->HasKey("wifiAccessPoints"));
 316     }
 317     EXPECT_TRUE(request_url.is_valid());
 318   }
 319
 320   GURL test_server_url_;
 321   base::MessageLoop main_message_loop_;
 322   scoped_refptr<FakeAccessTokenStore> access_token_store_;
 323   net::TestURLFetcherFactory url_fetcher_factory_;
 324   scoped_refptr<MockWifiDataProviderImpl> wifi_data_provider_;
 325 };
 326
 327 TEST_F(GeolocationNetworkProviderTest, CreateDestroy) {
 328   // Test fixture members were SetUp correctly.
 329   EXPECT_EQ(&main_message_loop_, base::MessageLoop::current());
 330   scoped_ptr<LocationProvider> provider(CreateProvider(true));
 331   EXPECT_TRUE(NULL != provider.get());
 332   provider.reset();
 333   SUCCEED();
 334 }
 335
 336 TEST_F(GeolocationNetworkProviderTest, StartProvider) {
 337   scoped_ptr<LocationProvider> provider(CreateProvider(true));
 338   EXPECT_TRUE(provider->StartProvider(false));
 339   net::TestURLFetcher* fetcher = get_url_fetcher_and_advance_id();
 340   ASSERT_TRUE(fetcher != NULL);
 341   CheckRequestIsValid(*fetcher, 0, 0, 0, std::string());
 342 }
 343
 344 TEST_F(GeolocationNetworkProviderTest, StartProviderDefaultUrl) {
 345   test_server_url_ = LocationArbitratorImpl::DefaultNetworkProviderURL();
 346   scoped_ptr<LocationProvider> provider(CreateProvider(true));
 347   EXPECT_TRUE(provider->StartProvider(false));
 348   net::TestURLFetcher* fetcher = get_url_fetcher_and_advance_id();
 349   ASSERT_TRUE(fetcher != NULL);
 350   CheckRequestIsValid(*fetcher, 0, 0, 0, std::string());
 351 }
 352
 353 TEST_F(GeolocationNetworkProviderTest, StartProviderLongRequest) {
 354   scoped_ptr<LocationProvider> provider(CreateProvider(true));
 355   EXPECT_TRUE(provider->StartProvider(false));
 356   const int kFirstScanAps = 20;
 357   wifi_data_provider_->SetData(CreateReferenceWifiScanData(kFirstScanAps));
 358   main_message_loop_.RunUntilIdle();
 359   net::TestURLFetcher* fetcher = get_url_fetcher_and_advance_id();
 360   ASSERT_TRUE(fetcher != NULL);
 361   // The request url should have been shortened to less than 2048 characters
 362   // in length by not including access points with the lowest signal strength
 363   // in the request.
 364   EXPECT_LT(fetcher->GetOriginalURL().spec().size(), size_t(2048));
 365   CheckRequestIsValid(*fetcher, 0, 16, 4, std::string());
 366 }
 367
 368 TEST_F(GeolocationNetworkProviderTest, MultipleWifiScansComplete) {
 369   scoped_ptr<LocationProvider> provider(CreateProvider(true));
 370   EXPECT_TRUE(provider->StartProvider(false));
 371
 372   net::TestURLFetcher* fetcher = get_url_fetcher_and_advance_id();
 373   ASSERT_TRUE(fetcher != NULL);
 374   EXPECT_TRUE(IsTestServerUrl(fetcher->GetOriginalURL()));
 375
 376   // Complete the network request with bad position fix.
 377   const char* kNoFixNetworkResponse =
 378       "{"
 379       "  \"status\": \"ZERO_RESULTS\""
 380       "}";
 381   fetcher->set_url(test_server_url_);
 382   fetcher->set_status(net::URLRequestStatus());
 383   fetcher->set_response_code(200);  // OK
 384   fetcher->SetResponseString(kNoFixNetworkResponse);
 385   fetcher->delegate()->OnURLFetchComplete(fetcher);
 386
 387   Geoposition position;
 388   provider->GetPosition(&position);
 389   EXPECT_FALSE(position.Validate());
 390
 391   // Now wifi data arrives -- SetData will notify listeners.
 392   const int kFirstScanAps = 6;
 393   wifi_data_provider_->SetData(CreateReferenceWifiScanData(kFirstScanAps));
 394   main_message_loop_.RunUntilIdle();
 395   fetcher = get_url_fetcher_and_advance_id();
 396   ASSERT_TRUE(fetcher != NULL);
 397   // The request should have the wifi data.
 398   CheckRequestIsValid(*fetcher, 0, kFirstScanAps, 0, std::string());
 399
 400   // Send a reply with good position fix.
 401   const char* kReferenceNetworkResponse =
 402       "{"
 403       "  \"accessToken\": \"" REFERENCE_ACCESS_TOKEN "\","
 404       "  \"accuracy\": 1200.4,"
 405       "  \"location\": {"
 406       "    \"lat\": 51.0,"
 407       "    \"lng\": -0.1"
 408       "  }"
 409       "}";
 410   fetcher->set_url(test_server_url_);
 411   fetcher->set_status(net::URLRequestStatus());
 412   fetcher->set_response_code(200);  // OK
 413   fetcher->SetResponseString(kReferenceNetworkResponse);
 414   fetcher->delegate()->OnURLFetchComplete(fetcher);
 415
 416   provider->GetPosition(&position);
 417   EXPECT_EQ(51.0, position.latitude);
 418   EXPECT_EQ(-0.1, position.longitude);
 419   EXPECT_EQ(1200.4, position.accuracy);
 420   EXPECT_FALSE(position.timestamp.is_null());
 421   EXPECT_TRUE(position.Validate());
 422
 423   // Token should be in the store.
 424   EXPECT_EQ(base::UTF8ToUTF16(REFERENCE_ACCESS_TOKEN),
 425             access_token_store_->access_token_set_[test_server_url_]);
 426
 427   // Wifi updated again, with one less AP. This is 'close enough' to the
 428   // previous scan, so no new request made.
 429   const int kSecondScanAps = kFirstScanAps - 1;
 430   wifi_data_provider_->SetData(CreateReferenceWifiScanData(kSecondScanAps));
 431   main_message_loop_.RunUntilIdle();
 432   fetcher = get_url_fetcher_and_advance_id();
 433   EXPECT_FALSE(fetcher);
 434
 435   provider->GetPosition(&position);
 436   EXPECT_EQ(51.0, position.latitude);
 437   EXPECT_EQ(-0.1, position.longitude);
 438   EXPECT_TRUE(position.Validate());
 439
 440   // Now a third scan with more than twice the original amount -> new request.
 441   const int kThirdScanAps = kFirstScanAps * 2 + 1;
 442   wifi_data_provider_->SetData(CreateReferenceWifiScanData(kThirdScanAps));
 443   main_message_loop_.RunUntilIdle();
 444   fetcher = get_url_fetcher_and_advance_id();
 445   EXPECT_TRUE(fetcher);
 446   CheckRequestIsValid(*fetcher, 0, kThirdScanAps, 0, REFERENCE_ACCESS_TOKEN);
 447   // ...reply with a network error.
 448
 449   fetcher->set_url(test_server_url_);
 450   fetcher->set_status(net::URLRequestStatus(net::URLRequestStatus::FAILED, -1));
 451   fetcher->set_response_code(200);  // should be ignored
 452   fetcher->SetResponseString(std::string());
 453   fetcher->delegate()->OnURLFetchComplete(fetcher);
 454
 455   // Error means we now no longer have a fix.
 456   provider->GetPosition(&position);
 457   EXPECT_FALSE(position.Validate());
 458
 459   // Wifi scan returns to original set: should be serviced from cache.
 460   wifi_data_provider_->SetData(CreateReferenceWifiScanData(kFirstScanAps));
 461   main_message_loop_.RunUntilIdle();
 462   EXPECT_FALSE(get_url_fetcher_and_advance_id());  // No new request created.
 463
 464   provider->GetPosition(&position);
 465   EXPECT_EQ(51.0, position.latitude);
 466   EXPECT_EQ(-0.1, position.longitude);
 467   EXPECT_TRUE(position.Validate());
 468 }
 469
 470 TEST_F(GeolocationNetworkProviderTest, NoRequestOnStartupUntilWifiData) {
 471   MessageLoopQuitListener listener;
 472   wifi_data_provider_->set_got_data(false);
 473   scoped_ptr<LocationProvider> provider(CreateProvider(true));
 474   EXPECT_TRUE(provider->StartProvider(false));
 475
 476   provider->SetUpdateCallback(
 477       base::Bind(&MessageLoopQuitListener::LocationUpdateAvailable,
 478                  base::Unretained(&listener)));
 479
 480   main_message_loop_.RunUntilIdle();
 481   EXPECT_FALSE(get_url_fetcher_and_advance_id())
 482       << "Network request should not be created right away on startup when "
 483          "wifi data has not yet arrived";
 484
 485   wifi_data_provider_->SetData(CreateReferenceWifiScanData(1));
 486   main_message_loop_.RunUntilIdle();
 487   EXPECT_TRUE(get_url_fetcher_and_advance_id());
 488 }
 489
 490 TEST_F(GeolocationNetworkProviderTest, NewDataReplacesExistingNetworkRequest) {
 491   // Send initial request with empty data
 492   scoped_ptr<LocationProvider> provider(CreateProvider(true));
 493   EXPECT_TRUE(provider->StartProvider(false));
 494   net::TestURLFetcher* fetcher = get_url_fetcher_and_advance_id();
 495   EXPECT_TRUE(fetcher);
 496
 497   // Now wifi data arrives; new request should be sent.
 498   wifi_data_provider_->SetData(CreateReferenceWifiScanData(4));
 499   main_message_loop_.RunUntilIdle();
 500   fetcher = get_url_fetcher_and_advance_id();
 501   EXPECT_TRUE(fetcher);
 502 }
 503
 504 TEST_F(GeolocationNetworkProviderTest, NetworkRequestDeferredForPermission) {
 505   scoped_ptr<LocationProvider> provider(CreateProvider(false));
 506   EXPECT_TRUE(provider->StartProvider(false));
 507   net::TestURLFetcher* fetcher = get_url_fetcher_and_advance_id();
 508   EXPECT_FALSE(fetcher);
 509   provider->OnPermissionGranted();
 510
 511   fetcher = get_url_fetcher_and_advance_id();
 512   ASSERT_TRUE(fetcher != NULL);
 513
 514   EXPECT_TRUE(IsTestServerUrl(fetcher->GetOriginalURL()));
 515 }
 516
 517 TEST_F(GeolocationNetworkProviderTest,
 518        NetworkRequestWithWifiDataDeferredForPermission) {
 519   access_token_store_->access_token_set_[test_server_url_] =
 520       base::UTF8ToUTF16(REFERENCE_ACCESS_TOKEN);
 521   scoped_ptr<LocationProvider> provider(CreateProvider(false));
 522   EXPECT_TRUE(provider->StartProvider(false));
 523   net::TestURLFetcher* fetcher = get_url_fetcher_and_advance_id();
 524   EXPECT_FALSE(fetcher);
 525
 526   static const int kScanCount = 4;
 527   wifi_data_provider_->SetData(CreateReferenceWifiScanData(kScanCount));
 528   main_message_loop_.RunUntilIdle();
 529
 530   fetcher = get_url_fetcher_and_advance_id();
 531   EXPECT_FALSE(fetcher);
 532
 533   provider->OnPermissionGranted();
 534
 535   fetcher = get_url_fetcher_and_advance_id();
 536   ASSERT_TRUE(fetcher != NULL);
 537
 538   CheckRequestIsValid(*fetcher, 0, kScanCount, 0, REFERENCE_ACCESS_TOKEN);
 539 }
 540
 541 TEST_F(GeolocationNetworkProviderTest, NetworkPositionCache) {
 542   NetworkLocationProvider::PositionCache cache;
 543
 544   const int kCacheSize = NetworkLocationProvider::PositionCache::kMaximumSize;
 545   for (int i = 1; i < kCacheSize * 2 + 1; ++i) {
 546     Geoposition pos = CreateReferencePosition(i);
 547     bool ret = cache.CachePosition(CreateReferenceWifiScanData(i), pos);
 548     EXPECT_TRUE(ret)  << i;
 549     const Geoposition* item =
 550         cache.FindPosition(CreateReferenceWifiScanData(i));
 551     ASSERT_TRUE(item) << i;
 552     EXPECT_EQ(pos.latitude, item->latitude)  << i;
 553     EXPECT_EQ(pos.longitude, item->longitude)  << i;
 554     if (i <= kCacheSize) {
 555       // Nothing should have spilled yet; check oldest item is still there.
 556       EXPECT_TRUE(cache.FindPosition(CreateReferenceWifiScanData(1)));
 557     } else {
 558       const int evicted = i - kCacheSize;
 559       EXPECT_FALSE(cache.FindPosition(CreateReferenceWifiScanData(evicted)));
 560       EXPECT_TRUE(cache.FindPosition(CreateReferenceWifiScanData(evicted + 1)));
 561     }
 562   }
 563 }
 564
 565 }  // namespace content