Reduce the site engagement service public interface.

chrome/browser/engagement/site_engagement_score_unittest.cc

Index: chrome/browser/engagement/site_engagement_score_unittest.cc
diff --git a/chrome/browser/engagement/site_engagement_score_unittest.cc b/chrome/browser/engagement/site_engagement_score_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..a536f927c0ba6dad4ea1bb8dbc5ae4c285bdc097
--- /dev/null
+++ b/chrome/browser/engagement/site_engagement_score_unittest.cc
@@ -0,0 +1,411 @@
+// 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 "chrome/browser/engagement/site_engagement_score.h"
+
+#include <utility>
+
+#include "base/macros.h"
+#include "base/test/simple_test_clock.h"
+#include "base/values.h"
+#include "chrome/browser/engagement/site_engagement_service.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace {
+
+const int kLessAccumulationsThanNeededToMaxDailyEngagement = 2;
+const int kMoreAccumulationsThanNeededToMaxDailyEngagement = 40;
+const int kMoreAccumulationsThanNeededToMaxTotalEngagement = 200;
+const int kLessDaysThanNeededToMaxTotalEngagement = 4;
+const int kMoreDaysThanNeededToMaxTotalEngagement = 40;
+const int kLessPeriodsThanNeededToDecayMaxScore = 2;
+const int kMorePeriodsThanNeededToDecayMaxScore = 40;
+
+base::Time GetReferenceTime() {
+  base::Time::Exploded exploded_reference_time;
+  exploded_reference_time.year = 2015;
+  exploded_reference_time.month = 1;
+  exploded_reference_time.day_of_month = 30;
+  exploded_reference_time.day_of_week = 5;
+  exploded_reference_time.hour = 11;
+  exploded_reference_time.minute = 0;
+  exploded_reference_time.second = 0;
+  exploded_reference_time.millisecond = 0;
+
+  return base::Time::FromLocalExploded(exploded_reference_time);
+}
+
+}  // namespace
+
+class SiteEngagementScoreTest : public testing::Test {
+ public:
+  SiteEngagementScoreTest() : score_(&test_clock_) {}
+
+  void SetUp() override {
+    testing::Test::SetUp();
+    // Disable the first engagement bonus for tests.
+    SiteEngagementScore::SetParamValuesForTesting();
+  }
+
+ protected:
+  void VerifyScore(const SiteEngagementScore& score,
+                   double expected_raw_score,
+                   double expected_points_added_today,
+                   base::Time expected_last_engagement_time) {
+    EXPECT_EQ(expected_raw_score, score.raw_score_);
+    EXPECT_EQ(expected_points_added_today, score.points_added_today_);
+    EXPECT_EQ(expected_last_engagement_time, score.last_engagement_time_);
+  }
+
+  void UpdateScore(SiteEngagementScore* score,
+                   double raw_score,
+                   double points_added_today,
+                   base::Time last_engagement_time) {
+    score->raw_score_ = raw_score;
+    score->points_added_today_ = points_added_today;
+    score->last_engagement_time_ = last_engagement_time;
+  }
+
+  void TestScoreInitializesAndUpdates(
+      base::DictionaryValue* score_dict,
+      double expected_raw_score,
+      double expected_points_added_today,
+      base::Time expected_last_engagement_time) {
+    SiteEngagementScore initial_score(&test_clock_, *score_dict);
+    VerifyScore(initial_score, expected_raw_score, expected_points_added_today,
+                expected_last_engagement_time);
+
+    // Updating the score dict should return false, as the score shouldn't
+    // have changed at this point.
+    EXPECT_FALSE(initial_score.UpdateScoreDict(score_dict));
+
+    // Update the score to new values and verify it updates the score dict
+    // correctly.
+    base::Time different_day =
+        GetReferenceTime() + base::TimeDelta::FromDays(1);
+    UpdateScore(&initial_score, 5, 10, different_day);
+    EXPECT_TRUE(initial_score.UpdateScoreDict(score_dict));
+    SiteEngagementScore updated_score(&test_clock_, *score_dict);
+    VerifyScore(updated_score, 5, 10, different_day);
+  }
+
+  void SetFirstDailyEngagementPointsForTesting(double points) {
+    SiteEngagementScore::param_values
+        [SiteEngagementScore::FIRST_DAILY_ENGAGEMENT] = points;
+  }
+
+  base::SimpleTestClock test_clock_;
+  SiteEngagementScore score_;
+};
+
+// Accumulate score many times on the same day. Ensure each time the score goes
+// up, but not more than the maximum per day.
+TEST_F(SiteEngagementScoreTest, AccumulateOnSameDay) {
+  base::Time reference_time = GetReferenceTime();
+
+  test_clock_.SetNow(reference_time);
+  for (int i = 0; i < kMoreAccumulationsThanNeededToMaxDailyEngagement; ++i) {
+    score_.AddPoints(SiteEngagementScore::GetNavigationPoints());
+    EXPECT_EQ(std::min(SiteEngagementScore::GetMaxPointsPerDay(),
+                       (i + 1) * SiteEngagementScore::GetNavigationPoints()),
+              score_.GetScore());
+  }
+
+  EXPECT_EQ(SiteEngagementScore::GetMaxPointsPerDay(), score_.GetScore());
+}
+
+// Accumulate on the first day to max that day's engagement, then accumulate on
+// a different day.
+TEST_F(SiteEngagementScoreTest, AccumulateOnTwoDays) {
+  base::Time reference_time = GetReferenceTime();
+  base::Time later_date = reference_time + base::TimeDelta::FromDays(2);
+
+  test_clock_.SetNow(reference_time);
+  for (int i = 0; i < kMoreAccumulationsThanNeededToMaxDailyEngagement; ++i)
+    score_.AddPoints(SiteEngagementScore::GetNavigationPoints());
+
+  EXPECT_EQ(SiteEngagementScore::GetMaxPointsPerDay(), score_.GetScore());
+
+  test_clock_.SetNow(later_date);
+  for (int i = 0; i < kMoreAccumulationsThanNeededToMaxDailyEngagement; ++i) {
+    score_.AddPoints(SiteEngagementScore::GetNavigationPoints());
+    double day_score =
+        std::min(SiteEngagementScore::GetMaxPointsPerDay(),
+                 (i + 1) * SiteEngagementScore::GetNavigationPoints());
+    EXPECT_EQ(day_score + SiteEngagementScore::GetMaxPointsPerDay(),
+              score_.GetScore());
+  }
+
+  EXPECT_EQ(2 * SiteEngagementScore::GetMaxPointsPerDay(), score_.GetScore());
+}
+
+// Accumulate score on many consecutive days and ensure the score doesn't exceed
+// the maximum allowed.
+TEST_F(SiteEngagementScoreTest, AccumulateALotOnManyDays) {
+  base::Time current_day = GetReferenceTime();
+
+  for (int i = 0; i < kMoreDaysThanNeededToMaxTotalEngagement; ++i) {
+    current_day += base::TimeDelta::FromDays(1);
+    test_clock_.SetNow(current_day);
+    for (int j = 0; j < kMoreAccumulationsThanNeededToMaxDailyEngagement; ++j)
+      score_.AddPoints(SiteEngagementScore::GetNavigationPoints());
+
+    EXPECT_EQ(std::min(SiteEngagementScore::kMaxPoints,
+                       (i + 1) * SiteEngagementScore::GetMaxPointsPerDay()),
+              score_.GetScore());
+  }
+
+  EXPECT_EQ(SiteEngagementScore::kMaxPoints, score_.GetScore());
+}
+
+// Accumulate a little on many consecutive days and ensure the score doesn't
+// exceed the maximum allowed.
+TEST_F(SiteEngagementScoreTest, AccumulateALittleOnManyDays) {
+  base::Time current_day = GetReferenceTime();
+
+  for (int i = 0; i < kMoreAccumulationsThanNeededToMaxTotalEngagement; ++i) {
+    current_day += base::TimeDelta::FromDays(1);
+    test_clock_.SetNow(current_day);
+
+    for (int j = 0; j < kLessAccumulationsThanNeededToMaxDailyEngagement; ++j)
+      score_.AddPoints(SiteEngagementScore::GetNavigationPoints());
+
+    EXPECT_EQ(
+        std::min(SiteEngagementScore::kMaxPoints,
+                 (i + 1) * kLessAccumulationsThanNeededToMaxDailyEngagement *
+                     SiteEngagementScore::GetNavigationPoints()),
+        score_.GetScore());
+  }
+
+  EXPECT_EQ(SiteEngagementScore::kMaxPoints, score_.GetScore());
+}
+
+// Accumulate a bit, then check the score decays properly for a range of times.
+TEST_F(SiteEngagementScoreTest, ScoresDecayOverTime) {
+  base::Time current_day = GetReferenceTime();
+
+  // First max the score.
+  for (int i = 0; i < kMoreDaysThanNeededToMaxTotalEngagement; ++i) {
+    current_day += base::TimeDelta::FromDays(1);
+    test_clock_.SetNow(current_day);
+
+    for (int j = 0; j < kMoreAccumulationsThanNeededToMaxDailyEngagement; ++j)
+      score_.AddPoints(SiteEngagementScore::GetNavigationPoints());
+  }
+
+  EXPECT_EQ(SiteEngagementScore::kMaxPoints, score_.GetScore());
+
+  // The score should not have decayed before the first decay period has
+  // elapsed.
+  test_clock_.SetNow(current_day +
+                     base::TimeDelta::FromDays(
+                         SiteEngagementScore::GetDecayPeriodInDays() - 1));
+  EXPECT_EQ(SiteEngagementScore::kMaxPoints, score_.GetScore());
+
+  // The score should have decayed by one chunk after one decay period has
+  // elapsed.
+  test_clock_.SetNow(
+      current_day +
+      base::TimeDelta::FromDays(SiteEngagementScore::GetDecayPeriodInDays()));
+  EXPECT_EQ(
+      SiteEngagementScore::kMaxPoints - SiteEngagementScore::GetDecayPoints(),
+      score_.GetScore());
+
+  // The score should have decayed by the right number of chunks after a few
+  // decay periods have elapsed.
+  test_clock_.SetNow(
+      current_day +
+      base::TimeDelta::FromDays(kLessPeriodsThanNeededToDecayMaxScore *
+                                SiteEngagementScore::GetDecayPeriodInDays()));
+  EXPECT_EQ(SiteEngagementScore::kMaxPoints -
+                kLessPeriodsThanNeededToDecayMaxScore *
+                    SiteEngagementScore::GetDecayPoints(),
+            score_.GetScore());
+
+  // The score should not decay below zero.
+  test_clock_.SetNow(
+      current_day +
+      base::TimeDelta::FromDays(kMorePeriodsThanNeededToDecayMaxScore *
+                                SiteEngagementScore::GetDecayPeriodInDays()));
+  EXPECT_EQ(0, score_.GetScore());
+}
+
+// Test that any expected decays are applied before adding points.
+TEST_F(SiteEngagementScoreTest, DecaysAppliedBeforeAdd) {
+  base::Time current_day = GetReferenceTime();
+
+  // Get the score up to something that can handle a bit of decay before
+  for (int i = 0; i < kLessDaysThanNeededToMaxTotalEngagement; ++i) {
+    current_day += base::TimeDelta::FromDays(1);
+    test_clock_.SetNow(current_day);
+
+    for (int j = 0; j < kMoreAccumulationsThanNeededToMaxDailyEngagement; ++j)
+      score_.AddPoints(SiteEngagementScore::GetNavigationPoints());
+  }
+
+  double initial_score = kLessDaysThanNeededToMaxTotalEngagement *
+                         SiteEngagementScore::GetMaxPointsPerDay();
+  EXPECT_EQ(initial_score, score_.GetScore());
+
+  // Go forward a few decay periods.
+  test_clock_.SetNow(
+      current_day +
+      base::TimeDelta::FromDays(kLessPeriodsThanNeededToDecayMaxScore *
+                                SiteEngagementScore::GetDecayPeriodInDays()));
+
+  double decayed_score = initial_score -
+                         kLessPeriodsThanNeededToDecayMaxScore *
+                             SiteEngagementScore::GetDecayPoints();
+  EXPECT_EQ(decayed_score, score_.GetScore());
+
+  // Now add some points.
+  score_.AddPoints(SiteEngagementScore::GetNavigationPoints());
+  EXPECT_EQ(decayed_score + SiteEngagementScore::GetNavigationPoints(),
+            score_.GetScore());
+}
+
+// Test that going back in time is handled properly.
+TEST_F(SiteEngagementScoreTest, GoBackInTime) {
+  base::Time current_day = GetReferenceTime();
+
+  test_clock_.SetNow(current_day);
+  for (int i = 0; i < kMoreAccumulationsThanNeededToMaxDailyEngagement; ++i)
+    score_.AddPoints(SiteEngagementScore::GetNavigationPoints());
+
+  EXPECT_EQ(SiteEngagementScore::GetMaxPointsPerDay(), score_.GetScore());
+
+  // Adding to the score on an earlier date should be treated like another day,
+  // and should not cause any decay.
+  test_clock_.SetNow(current_day - base::TimeDelta::FromDays(
+                                       kMorePeriodsThanNeededToDecayMaxScore *
+                                       SiteEngagementScore::GetDecayPoints()));
+  for (int i = 0; i < kMoreAccumulationsThanNeededToMaxDailyEngagement; ++i) {
+    score_.AddPoints(SiteEngagementScore::GetNavigationPoints());
+    double day_score =
+        std::min(SiteEngagementScore::GetMaxPointsPerDay(),
+                 (i + 1) * SiteEngagementScore::GetNavigationPoints());
+    EXPECT_EQ(day_score + SiteEngagementScore::GetMaxPointsPerDay(),
+              score_.GetScore());
+  }
+
+  EXPECT_EQ(2 * SiteEngagementScore::GetMaxPointsPerDay(), score_.GetScore());
+}
+
+// Test that scores are read / written correctly from / to empty score
+// dictionaries.
+TEST_F(SiteEngagementScoreTest, EmptyDictionary) {
+  base::DictionaryValue dict;
+  TestScoreInitializesAndUpdates(&dict, 0, 0, base::Time());
+}
+
+// Test that scores are read / written correctly from / to partially empty
+// score dictionaries.
+TEST_F(SiteEngagementScoreTest, PartiallyEmptyDictionary) {
+  base::DictionaryValue dict;
+  dict.SetDouble(SiteEngagementScore::kPointsAddedTodayKey, 2);
+
+  TestScoreInitializesAndUpdates(&dict, 0, 2, base::Time());
+}
+
+// Test that scores are read / written correctly from / to populated score
+// dictionaries.
+TEST_F(SiteEngagementScoreTest, PopulatedDictionary) {
+  base::DictionaryValue dict;
+  dict.SetDouble(SiteEngagementScore::kRawScoreKey, 1);
+  dict.SetDouble(SiteEngagementScore::kPointsAddedTodayKey, 2);
+  dict.SetDouble(SiteEngagementScore::kLastEngagementTimeKey,
+                 GetReferenceTime().ToInternalValue());
+
+  TestScoreInitializesAndUpdates(&dict, 1, 2, GetReferenceTime());
+}
+
+// Ensure bonus engagement is awarded for the first engagement of a day.
+TEST_F(SiteEngagementScoreTest, FirstDailyEngagementBonus) {
+  SetFirstDailyEngagementPointsForTesting(0.5);
+
+  SiteEngagementScore score1(&test_clock_);
+  SiteEngagementScore score2(&test_clock_);
+  base::Time current_day = GetReferenceTime();
+
+  test_clock_.SetNow(current_day);
+
+  // The first engagement event gets the bonus.
+  score1.AddPoints(0.5);
+  EXPECT_EQ(1.0, score1.GetScore());
+
+  // Subsequent events do not.
+  score1.AddPoints(0.5);
+  EXPECT_EQ(1.5, score1.GetScore());
+
+  // Bonuses are awarded independently between scores.
+  score2.AddPoints(1.0);
+  EXPECT_EQ(1.5, score2.GetScore());
+  score2.AddPoints(1.0);
+  EXPECT_EQ(2.5, score2.GetScore());
+
+  test_clock_.SetNow(current_day + base::TimeDelta::FromDays(1));
+
+  // The first event for the next day gets the bonus.
+  score1.AddPoints(0.5);
+  EXPECT_EQ(2.5, score1.GetScore());
+
+  // Subsequent events do not.
+  score1.AddPoints(0.5);
+  EXPECT_EQ(3.0, score1.GetScore());
+
+  score2.AddPoints(1.0);
+  EXPECT_EQ(4.0, score2.GetScore());
+  score2.AddPoints(1.0);
+  EXPECT_EQ(5.0, score2.GetScore());
+}
+
+// Test that resetting a score has the correct properties.
+TEST_F(SiteEngagementScoreTest, Reset) {
+  base::Time current_day = GetReferenceTime();
+
+  test_clock_.SetNow(current_day);
+  score_.AddPoints(SiteEngagementScore::GetNavigationPoints());
+  EXPECT_EQ(SiteEngagementScore::GetNavigationPoints(), score_.GetScore());
+
+  current_day += base::TimeDelta::FromDays(7);
+  test_clock_.SetNow(current_day);
+
+  score_.Reset(20.0, nullptr);
+  EXPECT_DOUBLE_EQ(20.0, score_.GetScore());
+  EXPECT_DOUBLE_EQ(0, score_.points_added_today_);
+  EXPECT_EQ(current_day, score_.last_engagement_time_);
+  EXPECT_TRUE(score_.last_shortcut_launch_time_.is_null());
+
+  // Adding points after the reset should work as normal.
+  score_.AddPoints(5);
+  EXPECT_EQ(25.0, score_.GetScore());
+
+  // The decay should happen one decay period from the current time.
+  test_clock_.SetNow(current_day +
+                     base::TimeDelta::FromDays(
+                         SiteEngagementScore::GetDecayPeriodInDays() + 1));
+  EXPECT_EQ(25.0 - SiteEngagementScore::GetDecayPoints(), score_.GetScore());
+
+  // Ensure that manually setting a time works as expected.
+  score_.AddPoints(5);
+  test_clock_.SetNow(GetReferenceTime());
+  base::Time now = test_clock_.Now();
+  score_.Reset(10.0, &now);
+
+  EXPECT_DOUBLE_EQ(10.0, score_.GetScore());
+  EXPECT_DOUBLE_EQ(0, score_.points_added_today_);
+  EXPECT_EQ(now, score_.last_engagement_time_);
+  EXPECT_TRUE(score_.last_shortcut_launch_time_.is_null());
+
+  score_.set_last_shortcut_launch_time(test_clock_.Now());
+  test_clock_.SetNow(GetReferenceTime() + base::TimeDelta::FromDays(3));
+  now = test_clock_.Now();
+  score_.Reset(15.0, &now);
+
+  // 5 bonus from the last shortcut launch.
+  EXPECT_DOUBLE_EQ(20.0, score_.GetScore());
+  EXPECT_DOUBLE_EQ(0, score_.points_added_today_);
+  EXPECT_EQ(now, score_.last_engagement_time_);
+  EXPECT_EQ(now, score_.last_shortcut_launch_time_);
+}