CPP: Implement PhoneNumberOfflineGeocoder.

Patch contributed by pmezard.

git-svn-id: http://libphonenumber.googlecode.com/svn/trunk@537 ee073f10-1060-11df-b6a4-87a95322a99c

4 files changed, 586 insertions, 0 deletions

diff --git a/cpp/CMakeLists.txt b/cpp/CMakeLists.txt
index f7c771a..0b782ed 100644
--- a/cpp/CMakeLists.txt
+++ b/cpp/CMakeLists.txt
@@ -185,6 +185,7 @@ set (
   "src/phonenumbers/geocoding/default_map_storage.cc"
   "src/phonenumbers/geocoding/geocoding_data.cc"
   "src/phonenumbers/geocoding/mapping_file_provider.cc"
+  "src/phonenumbers/geocoding/phonenumber_offline_geocoder.cc"
   "src/phonenumbers/logger.cc"
   "src/phonenumbers/phonemetadata.pb.cc" # Generated by Protocol Buffers.
   "src/phonenumbers/phonenumber.cc"
@@ -379,6 +380,7 @@ set (TEST_SOURCES
   "test/phonenumbers/geocoding/geocoding_data_test.cc"
   "test/phonenumbers/geocoding/geocoding_test_data.cc"
   "test/phonenumbers/geocoding/mapping_file_provider_test.cc"
+  "test/phonenumbers/geocoding/phonenumber_offline_geocoder_test.cc"
   "test/phonenumbers/logger_test.cc"
   "test/phonenumbers/phonenumberutil_test.cc"
   "test/phonenumbers/regexp_adapter_test.cc"
diff --git a/cpp/src/phonenumbers/geocoding/phonenumber_offline_geocoder.cc b/cpp/src/phonenumbers/geocoding/phonenumber_offline_geocoder.cc
new file mode 100644
index 0000000..9eac002
--- /dev/null
+++ b/cpp/src/phonenumbers/geocoding/phonenumber_offline_geocoder.cc
@@ -0,0 +1,216 @@
+// Copyright (C) 2012 The Libphonenumber Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Author: Patrick Mezard
+
+#include "phonenumbers/geocoding/phonenumber_offline_geocoder.h"
+
+#include <algorithm>
+#include <map>
+#include <string>
+
+#include <unicode/unistr.h>  // NOLINT(build/include_order)
+
+#include "phonenumbers/geocoding/area_code_map.h"
+#include "phonenumbers/geocoding/geocoding_data.h"
+#include "phonenumbers/geocoding/mapping_file_provider.h"
+#include "phonenumbers/phonenumberutil.h"
+#include "phonenumbers/stl_util.h"
+
+namespace i18n {
+namespace phonenumbers {
+
+using icu::UnicodeString;
+using std::map;
+using std::string;
+
+namespace {
+
+// Returns true if s1 comes strictly before s2 in lexicographic order.
+bool IsLowerThan(const char* s1, const char* s2) {
+  return strcmp(s1, s2) < 0;
+}
+
+}  // namespace
+
+PhoneNumberOfflineGeocoder::PhoneNumberOfflineGeocoder() {
+  Init(get_country_calling_codes(), get_country_calling_codes_size(),
+       get_country_languages, get_prefix_language_code_pairs(),
+       get_prefix_language_code_pairs_size(), get_prefix_descriptions);
+}
+
+PhoneNumberOfflineGeocoder::PhoneNumberOfflineGeocoder(
+    const int* country_calling_codes, int country_calling_codes_size,
+    country_languages_getter get_country_languages,
+    const char** prefix_language_code_pairs,
+    int prefix_language_code_pairs_size,
+    prefix_descriptions_getter get_prefix_descriptions) {
+  Init(country_calling_codes, country_calling_codes_size,
+       get_country_languages, prefix_language_code_pairs,
+       prefix_language_code_pairs_size, get_prefix_descriptions);
+}
+
+void PhoneNumberOfflineGeocoder::Init(
+    const int* country_calling_codes, int country_calling_codes_size,
+    country_languages_getter get_country_languages,
+    const char** prefix_language_code_pairs,
+    int prefix_language_code_pairs_size,
+    prefix_descriptions_getter get_prefix_descriptions) {
+  phone_util_ = PhoneNumberUtil::GetInstance();
+  provider_.reset(new MappingFileProvider(country_calling_codes,
+                                          country_calling_codes_size,
+                                          get_country_languages));
+  prefix_language_code_pairs_ = prefix_language_code_pairs;
+  prefix_language_code_pairs_size_ = prefix_language_code_pairs_size;
+  get_prefix_descriptions_ = get_prefix_descriptions;
+}
+
+PhoneNumberOfflineGeocoder::~PhoneNumberOfflineGeocoder() {
+  STLDeleteContainerPairSecondPointers(
+      available_maps_.begin(), available_maps_.end());
+}
+
+const AreaCodeMap* PhoneNumberOfflineGeocoder::GetPhonePrefixDescriptions(
+    int prefix, const string& language, const string& script,
+    const string& region) const {
+  string filename;
+  provider_->GetFileName(prefix, language, script, region, &filename);
+  if (filename.empty()) {
+    return NULL;
+  }
+  AreaCodeMaps::const_iterator it = available_maps_.find(filename);
+  if (it == available_maps_.end()) {
+    it = LoadAreaCodeMapFromFile(filename);
+    if (it == available_maps_.end()) {
+      return NULL;
+    }
+  }
+  return it->second;
+}
+
+PhoneNumberOfflineGeocoder::AreaCodeMaps::const_iterator
+PhoneNumberOfflineGeocoder::LoadAreaCodeMapFromFile(
+    const string& filename) const {
+  const char** const prefix_language_code_pairs_end =
+      prefix_language_code_pairs_ + prefix_language_code_pairs_size_;
+  const char** const prefix_language_code_pair =
+      std::lower_bound(prefix_language_code_pairs_,
+                       prefix_language_code_pairs_end,
+                       filename.c_str(), IsLowerThan);
+  if (prefix_language_code_pair != prefix_language_code_pairs_end &&
+      filename.compare(*prefix_language_code_pair) == 0) {
+    AreaCodeMap* const m = new AreaCodeMap();
+    m->ReadAreaCodeMap(get_prefix_descriptions_(
+            prefix_language_code_pair - prefix_language_code_pairs_));
+    return available_maps_.insert(AreaCodeMaps::value_type(filename, m)).first;
+  }
+  return available_maps_.end();
+}
+
+string PhoneNumberOfflineGeocoder::GetCountryNameForNumber(
+    const PhoneNumber& number, const Locale& language) const {
+  string region_code;
+  phone_util_->GetRegionCodeForNumber(number, &region_code);
+  return GetRegionDisplayName(&region_code, language);
+}
+
+string PhoneNumberOfflineGeocoder::GetRegionDisplayName(
+    const string* region_code, const Locale& language) const {
+  if (region_code == NULL || region_code->compare("ZZ") == 0 ||
+      region_code->compare(
+         PhoneNumberUtil::kRegionCodeForNonGeoEntity) == 0) {
+    return "";
+  }
+  UnicodeString udisplay_country;
+  icu::Locale("", region_code->c_str()).getDisplayCountry(
+      language, udisplay_country);
+  string display_country;
+  udisplay_country.toUTF8String(display_country);
+  return display_country;
+}
+
+string PhoneNumberOfflineGeocoder::GetDescriptionForValidNumber(
+    const PhoneNumber& number, const Locale& language) const {
+  const char* const description = GetAreaDescription(
+      number, language.getLanguage(), "", language.getCountry());
+  return *description != '\0'
+        ? description
+        : GetCountryNameForNumber(number, language);
+}
+
+string PhoneNumberOfflineGeocoder::GetDescriptionForValidNumber(
+    const PhoneNumber& number, const Locale& language,
+    const string& user_region) const {
+  // If the user region matches the number's region, then we just show the
+  // lower-level description, if one exists - if no description exists, we will
+  // show the region(country) name for the number.
+  string region_code;
+  phone_util_->GetRegionCodeForNumber(number, &region_code);
+  if (user_region.compare(region_code) == 0) {
+    return GetDescriptionForValidNumber(number, language);
+  }
+  // Otherwise, we just show the region(country) name for now.
+  return GetRegionDisplayName(&region_code, language);
+}
+
+string PhoneNumberOfflineGeocoder::GetDescriptionForNumber(
+    const PhoneNumber& number, const Locale& locale) const {
+  if (!phone_util_->IsValidNumber(number)) {
+    return "";
+  }
+  return GetDescriptionForValidNumber(number, locale);
+}
+
+string PhoneNumberOfflineGeocoder::GetDescriptionForNumber(
+    const PhoneNumber& number, const Locale& language,
+    const string& user_region) const {
+  if (!phone_util_->IsValidNumber(number)) {
+    return "";
+  }
+  return GetDescriptionForValidNumber(number, language, user_region);
+}
+
+const char* PhoneNumberOfflineGeocoder::GetAreaDescription(
+    const PhoneNumber& number, const string& lang, const string& script,
+    const string& region) const {
+  const int country_calling_code = number.country_code();
+  // NANPA area is not split in C++ code.
+  const int phone_prefix = country_calling_code;
+  const AreaCodeMap* const descriptions = GetPhonePrefixDescriptions(
+      phone_prefix, lang, script, region);
+  const char* description = descriptions ? descriptions->Lookup(number) : NULL;
+  // When a location is not available in the requested language, fall back to
+  // English.
+  if ((!description || *description == '\0') && MayFallBackToEnglish(lang)) {
+    const AreaCodeMap* default_descriptions = GetPhonePrefixDescriptions(
+        phone_prefix, "en", "", "");
+    if (!default_descriptions) {
+      return "";
+    }
+    description = default_descriptions->Lookup(number);
+  }
+  return description ? description : "";
+}
+
+// Don't fall back to English if the requested language is among the following:
+// - Chinese
+// - Japanese
+// - Korean
+bool PhoneNumberOfflineGeocoder::MayFallBackToEnglish(
+    const string& lang) const {
+  return lang.compare("zh") && lang.compare("ja") && lang.compare("ko");
+}
+
+}  // namespace phonenumbers
+}  // namespace i18n
diff --git a/cpp/src/phonenumbers/geocoding/phonenumber_offline_geocoder.h b/cpp/src/phonenumbers/geocoding/phonenumber_offline_geocoder.h
new file mode 100644
index 0000000..e0389b7
--- /dev/null
+++ b/cpp/src/phonenumbers/geocoding/phonenumber_offline_geocoder.h
@@ -0,0 +1,164 @@
+// Copyright (C) 2012 The Libphonenumber Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Author: Patrick Mezard
+
+#ifndef I18N_PHONENUMBERS_GEOCODING_PHONENUMBER_OFFLINE_GEOCODER_H_
+#define I18N_PHONENUMBERS_GEOCODING_PHONENUMBER_OFFLINE_GEOCODER_H_
+
+#include <map>
+#include <string>
+
+#include <unicode/locid.h>  // NOLINT(build/include_order)
+
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+
+namespace i18n {
+namespace phonenumbers {
+
+using std::map;
+using std::string;
+
+class AreaCodeMap;
+class MappingFileProvider;
+class PhoneNumber;
+class PhoneNumberUtil;
+struct CountryLanguages;
+struct PrefixDescriptions;
+typedef icu::Locale Locale;
+
+// An offline geocoder which provides geographical information related to a
+// phone number.
+class PhoneNumberOfflineGeocoder {
+ private:
+  typedef map<string, const AreaCodeMap*> AreaCodeMaps;
+
+ public:
+  typedef const CountryLanguages* (*country_languages_getter)(int index);
+  typedef const PrefixDescriptions* (*prefix_descriptions_getter)(int index);
+
+  PhoneNumberOfflineGeocoder();
+
+  // For tests
+  PhoneNumberOfflineGeocoder(
+      const int* country_calling_codes,
+      int country_calling_codes_size,
+      country_languages_getter get_country_languages,
+      const char** prefix_language_code_pairs,
+      int prefix_language_code_pairs_size,
+      prefix_descriptions_getter get_prefix_descriptions);
+
+  virtual ~PhoneNumberOfflineGeocoder();
+
+  // Returns a text description for the given phone number, in the language
+  // provided. The description might consist of the name of the country where
+  // the phone number is from, or the name of the geographical area the phone
+  // number is from if more detailed information is available.
+  //
+  // This method assumes the validity of the number passed in has already been
+  // checked.
+  string GetDescriptionForValidNumber(const PhoneNumber& number,
+                                      const Locale& language) const;
+
+  // As per GetDescriptionForValidNumber(PhoneNumber, Locale) but also considers
+  // the region of the user. If the phone number is from the same region as the
+  // user, only a lower-level description will be returned, if one exists.
+  // Otherwise, the phone number's region will be returned, with optionally some
+  // more detailed information.
+  //
+  // For example, for a user from the region "US" (United States), we would show
+  // "Mountain View, CA" for a particular number, omitting the United States
+  // from the description. For a user from the United Kingdom (region "GB"), for
+  // the same number we may show "Mountain View, CA, United States" or even just
+  // "United States".
+  //
+  // This method assumes the validity of the number passed in has already been
+  // checked.
+  //
+  // user_region is the region code for a given user. This region will be
+  // omitted from the description if the phone number comes from this region. It
+  // is a two-letter uppercase ISO country code as defined by ISO 3166-1.
+  string GetDescriptionForValidNumber(const PhoneNumber& number,
+      const Locale& language, const string& user_region) const;
+
+  // As per GetDescriptionForValidNumber(PhoneNumber, Locale) but explicitly
+  // checks the validity of the number passed in.
+  string GetDescriptionForNumber(const PhoneNumber& number,
+                                 const Locale& locale) const;
+
+  // As per GetDescriptionForValidNumber(PhoneNumber, Locale, String) but
+  string GetDescriptionForNumber(const PhoneNumber& number,
+      const Locale& language, const string& user_region) const;
+
+ private:
+  void Init(const int* country_calling_codes,
+            int country_calling_codes_size,
+            country_languages_getter get_country_languages,
+            const char** prefix_language_code_pairs,
+            int prefix_language_code_pairs_size,
+            prefix_descriptions_getter get_prefix_descriptions);
+
+  const AreaCodeMap* GetPhonePrefixDescriptions(int prefix,
+      const string& language, const string& script, const string& region) const;
+
+  AreaCodeMaps::const_iterator LoadAreaCodeMapFromFile(
+      const string& filename) const;
+
+  // Returns the customary display name in the given language for the given
+  // region.
+  string GetRegionDisplayName(const string* region_code,
+                              const Locale& language) const;
+
+  // Returns the customary display name in the given language for the given
+  // territory the phone number is from.
+  string GetCountryNameForNumber(const PhoneNumber& number,
+                                 const Locale& language) const;
+
+  // Returns an area-level text description in the given language for the given
+  // phone number, or an empty string.
+  // lang is a two-letter lowercase ISO language codes as defined by ISO 639-1.
+  // script is a four-letter titlecase (the first letter is uppercase and the
+  // rest of the letters are lowercase) ISO script codes as defined in ISO
+  // 15924.
+  // region is a two-letter uppercase ISO country codes as defined by ISO
+  // 3166-1.
+  const char* GetAreaDescription(const PhoneNumber& number, const string& lang,
+                                 const string& script,
+                                 const string& region) const;
+
+  bool MayFallBackToEnglish(const string& lang) const;
+
+ private:
+  const PhoneNumberUtil* phone_util_;
+  // The MappingFileProvider knows for which combination of country calling code
+  // and language a phone prefix mapping file is available in the file system,
+  // so that a file can be loaded when needed.
+  scoped_ptr<const MappingFileProvider> provider_;
+
+  const char** prefix_language_code_pairs_;
+  int prefix_language_code_pairs_size_;
+  prefix_descriptions_getter get_prefix_descriptions_;
+
+  // A mapping from country calling codes languages pairs to the corresponding
+  // phone prefix map that has been loaded.
+  mutable AreaCodeMaps available_maps_;
+
+  DISALLOW_COPY_AND_ASSIGN(PhoneNumberOfflineGeocoder);
+};
+
+}  // namespace phonenumbers
+}  // namespace i18n
+
+#endif /* I18N_PHONENUMBERS_GEOCODING_PHONENUMBER_OFFLINE_GEOCODER_H_ */
diff --git a/cpp/test/phonenumbers/geocoding/phonenumber_offline_geocoder_test.cc b/cpp/test/phonenumbers/geocoding/phonenumber_offline_geocoder_test.cc
new file mode 100644
index 0000000..fcb6b3f
--- /dev/null
+++ b/cpp/test/phonenumbers/geocoding/phonenumber_offline_geocoder_test.cc
@@ -0,0 +1,204 @@
+// Copyright (C) 2012 The Libphonenumber Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Author: Patrick Mezard
+
+#include "phonenumbers/geocoding/phonenumber_offline_geocoder.h"
+
+#include <gtest/gtest.h>
+#include <unicode/locid.h>
+
+#include "phonenumbers/geocoding/geocoding_test_data.h"
+#include "phonenumbers/phonenumber.h"
+#include "phonenumbers/phonenumber.pb.h"
+
+namespace i18n {
+namespace phonenumbers {
+
+using icu::Locale;
+
+namespace {
+
+PhoneNumber MakeNumber(int32 country_code, uint64 national_number) {
+  PhoneNumber n;
+  n.set_country_code(country_code);
+  n.set_national_number(national_number);
+  return n;
+}
+
+const Locale kEnglishLocale = Locale("en", "GB");
+const Locale kFrenchLocale = Locale("fr", "FR");
+const Locale kGermanLocale = Locale("de", "DE");
+const Locale kItalianLocale = Locale("it", "IT");
+const Locale kKoreanLocale = Locale("ko", "KR");
+const Locale kSimplifiedChineseLocale = Locale("zh", "CN");
+
+}  // namespace
+
+class PhoneNumberOfflineGeocoderTest : public testing::Test {
+ protected:
+  PhoneNumberOfflineGeocoderTest() :
+    KO_NUMBER1(MakeNumber(82, 22123456L)),
+    KO_NUMBER2(MakeNumber(82, 322123456L)),
+    KO_NUMBER3(MakeNumber(82, 6421234567L)),
+    KO_INVALID_NUMBER(MakeNumber(82, 1234L)),
+    US_NUMBER1(MakeNumber(1, 6502530000L)),
+    US_NUMBER2(MakeNumber(1, 6509600000L)),
+    US_NUMBER3(MakeNumber(1, 2128120000L)),
+    US_NUMBER4(MakeNumber(1, 6174240000L)),
+    US_INVALID_NUMBER(MakeNumber(1, 123456789L)),
+    BS_NUMBER1(MakeNumber(1, 2423651234L)),
+    AU_NUMBER(MakeNumber(61, 236618300L)),
+    NUMBER_WITH_INVALID_COUNTRY_CODE(MakeNumber(999, 2423651234L)),
+    INTERNATIONAL_TOLL_FREE(MakeNumber(800, 12345678L)) {
+  }
+
+  virtual void SetUp() {
+    geocoder_.reset(
+        new PhoneNumberOfflineGeocoder(
+            get_test_country_calling_codes(),
+            get_test_country_calling_codes_size(),
+            get_test_country_languages,
+            get_test_prefix_language_code_pairs(),
+            get_test_prefix_language_code_pairs_size(),
+            get_test_prefix_descriptions));
+  }
+
+ protected:
+  scoped_ptr<PhoneNumberOfflineGeocoder> geocoder_;
+
+  const PhoneNumber KO_NUMBER1;
+  const PhoneNumber KO_NUMBER2;
+  const PhoneNumber KO_NUMBER3;
+  const PhoneNumber KO_INVALID_NUMBER;
+
+  const PhoneNumber US_NUMBER1;
+  const PhoneNumber US_NUMBER2;
+  const PhoneNumber US_NUMBER3;
+  const PhoneNumber US_NUMBER4;
+  const PhoneNumber US_INVALID_NUMBER;
+
+  const PhoneNumber BS_NUMBER1;
+  const PhoneNumber AU_NUMBER;
+  const PhoneNumber NUMBER_WITH_INVALID_COUNTRY_CODE;
+  const PhoneNumber INTERNATIONAL_TOLL_FREE;
+};
+
+TEST_F(PhoneNumberOfflineGeocoderTest,
+       TestGetDescriptionForNumberWithNoDataFile) {
+  // No data file containing mappings for US numbers is available in Chinese for
+  // the unittests. As a result, the country name of United States in simplified
+  // Chinese is returned.
+
+  // "\u7F8E\u56FD" (unicode escape sequences are not always supported)
+  EXPECT_EQ("\xe7""\xbe""\x8e""\xe5""\x9b""\xbd",
+            geocoder_->GetDescriptionForNumber(US_NUMBER1,
+                                               kSimplifiedChineseLocale));
+  EXPECT_EQ("Bahamas",
+            geocoder_->GetDescriptionForNumber(BS_NUMBER1, Locale("en", "US")));
+  EXPECT_EQ("Australia",
+            geocoder_->GetDescriptionForNumber(AU_NUMBER, Locale("en", "US")));
+  EXPECT_EQ("",
+            geocoder_->GetDescriptionForNumber(NUMBER_WITH_INVALID_COUNTRY_CODE,
+                                               Locale("en", "US")));
+  EXPECT_EQ("",
+            geocoder_->GetDescriptionForNumber(INTERNATIONAL_TOLL_FREE,
+                                               Locale("en", "US")));
+}
+
+TEST_F(PhoneNumberOfflineGeocoderTest,
+       TestGetDescriptionForNumberWithMissingPrefix) {
+  // Test that the name of the country is returned when the number passed in is
+  // valid but not covered by the geocoding data file.
+  EXPECT_EQ("United States",
+            geocoder_->GetDescriptionForNumber(US_NUMBER4, Locale("en", "US")));
+}
+
+TEST_F(PhoneNumberOfflineGeocoderTest, TestGetDescriptionForNumber_en_US) {
+  EXPECT_EQ("CA",
+            geocoder_->GetDescriptionForNumber(US_NUMBER1, Locale("en", "US")));
+  EXPECT_EQ("Mountain View, CA",
+            geocoder_->GetDescriptionForNumber(US_NUMBER2, Locale("en", "US")));
+  EXPECT_EQ("New York, NY",
+            geocoder_->GetDescriptionForNumber(US_NUMBER3, Locale("en", "US")));
+}
+
+TEST_F(PhoneNumberOfflineGeocoderTest, TestGetDescriptionForKoreanNumber) {
+  EXPECT_EQ("Seoul",
+            geocoder_->GetDescriptionForNumber(KO_NUMBER1, kEnglishLocale));
+  EXPECT_EQ("Incheon",
+            geocoder_->GetDescriptionForNumber(KO_NUMBER2, kEnglishLocale));
+  EXPECT_EQ("Jeju",
+            geocoder_->GetDescriptionForNumber(KO_NUMBER3, kEnglishLocale));
+  // "\uC11C\uC6B8"
+  EXPECT_EQ("\xec""\x84""\x9c""\xec""\x9a""\xb8",
+            geocoder_->GetDescriptionForNumber(KO_NUMBER1, kKoreanLocale));
+  // "\uC778\uCC9C"
+  EXPECT_EQ("\xec""\x9d""\xb8""\xec""\xb2""\x9c",
+            geocoder_->GetDescriptionForNumber(KO_NUMBER2, kKoreanLocale));
+}
+
+TEST_F(PhoneNumberOfflineGeocoderTest, TestGetDescriptionForFallBack) {
+  // No fallback, as the location name for the given phone number is available
+  // in the requested language.
+  EXPECT_EQ("Kalifornien",
+            geocoder_->GetDescriptionForNumber(US_NUMBER1, kGermanLocale));
+  // German falls back to English.
+  EXPECT_EQ("New York, NY",
+            geocoder_->GetDescriptionForNumber(US_NUMBER3, kGermanLocale));
+  // Italian falls back to English.
+  EXPECT_EQ("CA",
+            geocoder_->GetDescriptionForNumber(US_NUMBER1, kItalianLocale));
+  // Korean doesn't fall back to English.
+  // "\uB300\uD55C\uBBFC\uAD6D"
+  EXPECT_EQ("\xeb""\x8c""\x80""\xed""\x95""\x9c""\xeb""\xaf""\xbc""\xea""\xb5"
+            "\xad",
+            geocoder_->GetDescriptionForNumber(KO_NUMBER3, kKoreanLocale));
+}
+
+TEST_F(PhoneNumberOfflineGeocoderTest,
+       TestGetDescriptionForNumberWithUserRegion) {
+  // User in Italy, American number. We should just show United States, in
+  // Spanish, and not more detailed information.
+  EXPECT_EQ("Estados Unidos",
+            geocoder_->GetDescriptionForNumber(US_NUMBER1, Locale("es", "ES"),
+                                               "IT"));
+  // Unknown region - should just show country name.
+  EXPECT_EQ("Estados Unidos",
+            geocoder_->GetDescriptionForNumber(US_NUMBER1, Locale("es", "ES"),
+                                               "ZZ"));
+  // User in the States, language German, should show detailed data.
+  EXPECT_EQ("Kalifornien",
+            geocoder_->GetDescriptionForNumber(US_NUMBER1, kGermanLocale,
+                                               "US"));
+  // User in the States, language French, no data for French, so we fallback to
+  // English detailed data.
+  EXPECT_EQ("CA",
+            geocoder_->GetDescriptionForNumber(US_NUMBER1, kFrenchLocale,
+                                               "US"));
+  // Invalid number - return an empty string.
+  EXPECT_EQ("",
+            geocoder_->GetDescriptionForNumber(US_INVALID_NUMBER,
+                                               kEnglishLocale, "US"));
+}
+
+TEST_F(PhoneNumberOfflineGeocoderTest, TestGetDescriptionForInvalidNumber) {
+  EXPECT_EQ("", geocoder_->GetDescriptionForNumber(KO_INVALID_NUMBER,
+                                                   kEnglishLocale));
+  EXPECT_EQ("", geocoder_->GetDescriptionForNumber(US_INVALID_NUMBER,
+                                                   kEnglishLocale));
+}
+
+}  // namespace phonenumbers
+}  // namespace i18n