[translate] Add translate ranker model loader.

components/translate/core/browser/translate_ranker_unittest.cc

-// Copyright 2016 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 "components/translate/core/browser/translate_ranker.h"
-
-#include <initializer_list>
-#include <memory>
-
-#include "base/feature_list.h"
-#include "base/strings/stringprintf.h"
-#include "base/test/scoped_feature_list.h"
-#include "components/metrics/proto/translate_event.pb.h"
-#include "components/prefs/scoped_user_pref_update.h"
-#include "components/sync_preferences/testing_pref_service_syncable.h"
-#include "components/translate/core/browser/proto/translate_ranker_model.pb.h"
-#include "components/translate/core/browser/translate_download_manager.h"
-#include "components/translate/core/browser/translate_prefs.h"
-#include "testing/gtest/include/gtest/gtest.h"
-
-namespace translate {
-
-class TranslateRankerTest : public ::testing::Test {
- protected:
-  TranslateRankerTest() {}
-
-  void SetUp() override {
-    locale_ = TranslateDownloadManager::GetInstance()->application_locale();
-    TranslateDownloadManager::GetInstance()->set_application_locale("zh-CN");
-
-    // Setup a 50/50 accepted/denied count for "english" when initialize the
-    // prefs and translate prefs.
-    base::DictionaryValue lang_count;
-    lang_count.SetInteger("en", 50);
-    prefs_.reset(new sync_preferences::TestingPrefServiceSyncable());
-    TranslatePrefs::RegisterProfilePrefs(prefs_->registry());
-    prefs_->Set(TranslatePrefs::kPrefTranslateAcceptedCount, lang_count);
-    prefs_->Set(TranslatePrefs::kPrefTranslateDeniedCount, lang_count);
-    translate_prefs_.reset(new TranslatePrefs(
-        prefs_.get(), "intl.accept_languages", kPreferredLanguagePrefs));
-    translate_prefs_->SetCountry("us");
-  }
-
-  void TearDown() override {
-    TranslateDownloadManager::GetInstance()->set_application_locale(locale_);
-  }
-
-  void InitFeatures(const std::initializer_list<base::Feature>& enabled,
-                    const std::initializer_list<base::Feature>& disabled) {
-    scoped_feature_list_.InitWithFeatures(enabled, disabled);
-  }
-
-  static std::unique_ptr<TranslateRanker> GetRankerForTest(float bias) {
-    chrome_intelligence::TranslateRankerModel model;
-    chrome_intelligence::TranslateRankerModel::LogisticRegressionModel*
-        details = model.mutable_logistic_regression_model();
-    details->set_bias(bias);
-    details->set_accept_ratio_weight(0.02f);
-    details->set_decline_ratio_weight(0.03f);
-    details->set_accept_count_weight(0.13f);
-    details->set_decline_count_weight(-0.14f);
-
-    auto& src_language_weight = *details->mutable_source_language_weight();
-    src_language_weight["en"] = 0.04f;
-    src_language_weight["fr"] = 0.05f;
-    src_language_weight["zh"] = 0.06f;
-
-    auto& dest_language_weight = *details->mutable_dest_language_weight();
-    dest_language_weight["UNKNOWN"] = 0.00f;
-
-    auto& country_weight = *details->mutable_country_weight();
-    country_weight["us"] = 0.07f;
-    country_weight["ca"] = 0.08f;
-    country_weight["cn"] = 0.09f;
-
-    auto& locale_weight = *details->mutable_locale_weight();
-    locale_weight["en-us"] = 0.10f;
-    locale_weight["en-ca"] = 0.11f;
-    locale_weight["zh-cn"] = 0.12f;  // Normalized to lowercase.
-
-    return TranslateRanker::CreateForTesting(model.SerializeAsString());
-  }
-
-  static double Sigmoid(double x) { return 1.0 / (1.0 + exp(-x)); }
-
-  static metrics::TranslateEventProto CreateTranslateEvent(
-      const std::string& src_lang,
-      const std::string& dst_lang,
-      int accept_count,
-      int decline_count,
-      int ignore_count) {
-    metrics::TranslateEventProto translate_event;
-    translate_event.set_source_language(src_lang);
-    translate_event.set_target_language(dst_lang);
-    translate_event.set_accept_count(accept_count);
-    translate_event.set_decline_count(decline_count);
-    translate_event.set_ignore_count(ignore_count);
-    return translate_event;
-  }
-
-  static const char* const kPreferredLanguagePrefs;
-
-  std::unique_ptr<sync_preferences::TestingPrefServiceSyncable> prefs_;
-  std::unique_ptr<translate::TranslatePrefs> translate_prefs_;
-
- private:
-  // Manages the enabling/disabling of features within the scope of a test.
-  base::test::ScopedFeatureList scoped_feature_list_;
-
-  // Cache and reset the application locale for each test.
-  std::string locale_;
-
-  DISALLOW_COPY_AND_ASSIGN(TranslateRankerTest);
-};
-
-const char* const TranslateRankerTest::kPreferredLanguagePrefs =
-#if defined(OS_CHROMEOS)
-    "settings.language.preferred_languages";
-#else
-    nullptr;
-#endif
-
-TEST_F(TranslateRankerTest, DisabledByDefault) {
-  InitFeatures({}, {});
-  EXPECT_FALSE(TranslateRanker::IsEnabled());
-}
-
-TEST_F(TranslateRankerTest, Disabled) {
-  InitFeatures({}, {kTranslateRankerQuery, kTranslateRankerEnforcement});
-  EXPECT_FALSE(TranslateRanker::IsEnabled());
-}
-
-TEST_F(TranslateRankerTest, EnableQuery) {
-  InitFeatures({kTranslateRankerQuery}, {kTranslateRankerEnforcement});
-  EXPECT_TRUE(TranslateRanker::IsEnabled());
-}
-
-TEST_F(TranslateRankerTest, EnableEnforcement) {
-  InitFeatures({kTranslateRankerEnforcement}, {kTranslateRankerQuery});
-  EXPECT_TRUE(TranslateRanker::IsEnabled());
-}
-
-TEST_F(TranslateRankerTest, EnableQueryAndEnforcement) {
-  InitFeatures({kTranslateRankerQuery, kTranslateRankerEnforcement}, {});
-  EXPECT_TRUE(TranslateRanker::IsEnabled());
-  EXPECT_FALSE(TranslateRanker::IsLoggingEnabled());
-}
-
-TEST_F(TranslateRankerTest, EnableLogging) {
-  InitFeatures({kTranslateRankerLogging}, {});
-  EXPECT_FALSE(TranslateRanker::IsEnabled());
-  EXPECT_TRUE(TranslateRanker::IsLoggingEnabled());
-}
-
-
-TEST_F(TranslateRankerTest, CalculateScore) {
-  InitFeatures({kTranslateRankerQuery, kTranslateRankerEnforcement}, {});
-  std::unique_ptr<translate::TranslateRanker> ranker = GetRankerForTest(0.01f);
-  // Calculate the score using: a 50:50 accept/decline ratio; the one-hot
-  // values for the src lang, dest lang, locale and counry; and, the bias.
-  double expected = Sigmoid(0.5 * 0.02f +    // accept ratio * weight
-                            0.5 * 0.03f +    // decline ratio * weight
-                            0.0 * 0.00f +    // ignore ratio * (default) weight
-                            50.0 * 0.13f +   // accept count * weight
-                            50.0 * -0.14f +  // decline count * weight
-                            0.0 * 0.00f +    // ignore count * (default) weight
-                            1.0 * 0.04f +  // one-hot src-language "en" * weight
-                            1.0 * 0.00f +  // one-hot dst-language "fr" * weight
-                            1.0 * 0.07f +  // one-hot country * weight
-                            1.0 * 0.12f +  // one-hot locale * weight
-                            0.01f);        // bias
-
-  EXPECT_NEAR(expected,
-              ranker->CalculateScore(50, 50, 0, "en", "fr", "zh-CN", "us"),
-              0.000001);
-}
-
-TEST_F(TranslateRankerTest, ShouldOfferTranslation) {
-  InitFeatures({kTranslateRankerQuery, kTranslateRankerEnforcement}, {});
-  // With a bias of -0.5 en->fr is not over the threshold.
-  EXPECT_FALSE(GetRankerForTest(-0.5f)->ShouldOfferTranslation(
-      *translate_prefs_, "en", "fr"));
-  // With a bias of 0.25 en-fr is over the threshold.
-  EXPECT_TRUE(GetRankerForTest(0.25f)->ShouldOfferTranslation(*translate_prefs_,
-                                                              "en", "fr"));
-}
-
-TEST_F(TranslateRankerTest, RecordAndFlushEvents) {
-  InitFeatures({kTranslateRankerLogging}, {});
-  std::unique_ptr<translate::TranslateRanker> ranker = GetRankerForTest(0.0f);
-  std::vector<metrics::TranslateEventProto> flushed_events;
-
-  // Check that flushing an empty cache will return an empty vector.
-  ranker->FlushTranslateEvents(&flushed_events);
-  EXPECT_EQ(0U, flushed_events.size());
-
-  auto event_1 = CreateTranslateEvent("fr", "en", 1, 0, 3);
-  auto event_2 = CreateTranslateEvent("jp", "en", 2, 0, 3);
-  auto event_3 = CreateTranslateEvent("es", "de", 4, 5, 6);
-  ranker->RecordTranslateEvent(event_1);
-  ranker->RecordTranslateEvent(event_2);
-  ranker->RecordTranslateEvent(event_3);
-
-  // Capture the data and verify that it is as expected.
-  ranker->FlushTranslateEvents(&flushed_events);
-  EXPECT_EQ(3U, flushed_events.size());
-  ASSERT_EQ("fr", flushed_events[0].source_language());
-  ASSERT_EQ("jp", flushed_events[1].source_language());
-  ASSERT_EQ("es", flushed_events[2].source_language());
-
-  // Check that the cache has been cleared.
-  ranker->FlushTranslateEvents(&flushed_events);
-  EXPECT_EQ(0U, flushed_events.size());
-}
-
-TEST_F(TranslateRankerTest, LoggingDisabled) {
-  InitFeatures({}, {kTranslateRankerLogging});
-  std::unique_ptr<translate::TranslateRanker> ranker = GetRankerForTest(0.0f);
-  std::vector<metrics::TranslateEventProto> flushed_events;
-
-  ranker->FlushTranslateEvents(&flushed_events);
-  EXPECT_EQ(0U, flushed_events.size());
-
-  auto event_1 = CreateTranslateEvent("fr", "en", 1, 0, 3);
-  auto event_2 = CreateTranslateEvent("jp", "en", 2, 0, 3);
-  auto event_3 = CreateTranslateEvent("es", "de", 4, 5, 6);
-  ranker->RecordTranslateEvent(event_1);
-  ranker->RecordTranslateEvent(event_2);
-  ranker->RecordTranslateEvent(event_3);
-
-  // Logging is disabled, so no events should be cached.
-  ranker->FlushTranslateEvents(&flushed_events);
-  EXPECT_EQ(0U, flushed_events.size());
-}
-
-}  // namespace translate