[LanguageModel] Return top languages only with a reasonable sample set

components/translate/core/browser/language_model_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/language_model.h"
 
 #include "components/prefs/testing_pref_service.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using testing::ElementsAre;
 using testing::FloatEq;
 using testing::Gt;
 
 namespace {
 
 const char kLang1[] = "en";
 const char kLang2[] = "de";
 const char kLang3[] = "es";
 
 }  // namespace
 
 namespace translate {
 
 TEST(LanguageModelTest, ListSorted) {
   TestingPrefServiceSimple prefs;
   LanguageModel::RegisterProfilePrefs(prefs.registry());
   LanguageModel model(&prefs);
 
-  model.OnPageVisited(kLang1);
-  model.OnPageVisited(kLang1);
-  model.OnPageVisited(kLang1);
-  model.OnPageVisited(kLang2);
+  for (int i = 0; i < 50; i++) {
+    model.OnPageVisited(kLang1);
+    model.OnPageVisited(kLang1);
+    model.OnPageVisited(kLang1);
+    model.OnPageVisited(kLang2);
+  }
 
   EXPECT_THAT(model.GetTopLanguages(),
               ElementsAre(LanguageModel::LanguageInfo{kLang1},
                           LanguageModel::LanguageInfo{kLang2}));
 }
 
 TEST(LanguageModelTest, ListSortedReversed) {
   TestingPrefServiceSimple prefs;
   LanguageModel::RegisterProfilePrefs(prefs.registry());
   LanguageModel model(&prefs);
 
-  model.OnPageVisited(kLang2);
-  model.OnPageVisited(kLang1);
-  model.OnPageVisited(kLang1);
-  model.OnPageVisited(kLang1);
+  for (int i = 0; i < 50; i++) {
+    model.OnPageVisited(kLang2);
+    model.OnPageVisited(kLang1);
+    model.OnPageVisited(kLang1);
+    model.OnPageVisited(kLang1);
+  }
 
   EXPECT_THAT(model.GetTopLanguages(),
               ElementsAre(LanguageModel::LanguageInfo{kLang1},
                           LanguageModel::LanguageInfo{kLang2}));
 }
 
 TEST(LanguageModelTest, RightFrequencies) {
   TestingPrefServiceSimple prefs;
   LanguageModel::RegisterProfilePrefs(prefs.registry());
   LanguageModel model(&prefs);
 
-  model.OnPageVisited(kLang1);
-  model.OnPageVisited(kLang1);
-  model.OnPageVisited(kLang1);
-  model.OnPageVisited(kLang2);
+  for (int i = 0; i < 50; i++) {
+    model.OnPageVisited(kLang1);
+    model.OnPageVisited(kLang1);
+    model.OnPageVisited(kLang1);
+    model.OnPageVisited(kLang2);
+  }
 
   // Corresponding frequencies are given by the model.
   EXPECT_THAT(model.GetLanguageFrequency(kLang1), FloatEq(0.75f));
   EXPECT_THAT(model.GetLanguageFrequency(kLang2), FloatEq(0.25f));
   // An unknown language gets frequency 0.
   EXPECT_THAT(model.GetLanguageFrequency(kLang3), 0);
 }
 
 TEST(LanguageModelTest, RareLanguageDiscarded) {
   TestingPrefServiceSimple prefs;
@@ skipping 10 matching lines @@
 
   // Another 100 visits cause the cleanup (total > 1000).
   for (int i = 0; i < 100; i++)
     model.OnPageVisited(kLang1);
   // Lang 2 is removed from the model.
   EXPECT_THAT(model.GetTopLanguages(),
               ElementsAre(LanguageModel::LanguageInfo{kLang1, 1}));
 }
 
 }  // namespace translate