components/translate/core/language_detection/language_detection_model_unittest.cc

// Copyright 2020 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/language_detection/language_detection_model.h"

#include "base/files/file_util.h"
#include "base/files/scoped_temp_dir.h"
#include "base/path_service.h"
#include "base/strings/utf_string_conversions.h"
#include "base/test/metrics/histogram_tester.h"
#include "components/translate/core/common/translate_constants.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace translate {

base::File CreateInvalidModelFile() {
  base::ScopedTempDir temp_dir;
  EXPECT_TRUE(temp_dir.CreateUniqueTempDir());
  base::FilePath file_path =
      temp_dir.GetPath().AppendASCII("model_file.tflite");
  base::File file(file_path, (base::File::FLAG_CREATE | base::File::FLAG_READ |
                              base::File::FLAG_WRITE |
                              base::File::FLAG_CAN_DELETE_ON_CLOSE));
  EXPECT_TRUE(file.WriteAtCurrentPos("12345", 5));
  return file;
}

base::File GetValidModelFile() {
  base::FilePath source_root_dir;
  base::PathService::Get(base::DIR_SOURCE_ROOT, &source_root_dir);
  base::FilePath model_file_path = source_root_dir.AppendASCII("components")
                                       .AppendASCII("test")
                                       .AppendASCII("data")
                                       .AppendASCII("translate")
                                       .AppendASCII("valid_model.tflite");
  base::File file(model_file_path,
                  (base::File::FLAG_OPEN | base::File::FLAG_READ));
  return file;
}

TEST(LanguageDetectionModelTest, ModelUnavailable) {
  LanguageDetectionModel language_detection_model;
  EXPECT_FALSE(language_detection_model.IsAvailable());
}

TEST(LanguageDetectionModelTest, EmptyFileProvided) {
  base::HistogramTester histogram_tester;
  LanguageDetectionModel language_detection_model;
  language_detection_model.UpdateWithFile(base::File());

  EXPECT_FALSE(language_detection_model.IsAvailable());
  histogram_tester.ExpectUniqueSample(
      "LanguageDetection.TFLiteModel.LanguageDetectionModelState",
      LanguageDetectionModelState::kModelFileInvalid, 1);
}

// TODO(crbug.com/1240561): Fix flaky test.
TEST(LanguageDetectionModelTest, DISABLED_UnsupportedModelFileProvided) {
  base::HistogramTester histogram_tester;

  base::File file = CreateInvalidModelFile();
  LanguageDetectionModel language_detection_model;
  language_detection_model.UpdateWithFile(std::move(file));
  EXPECT_FALSE(language_detection_model.IsAvailable());
  histogram_tester.ExpectUniqueSample(
      "LanguageDetection.TFLiteModel.LanguageDetectionModelState",
      LanguageDetectionModelState::kModelFileValidAndMemoryMapped, 1);
  histogram_tester.ExpectUniqueSample(
      "LanguageDetection.TFLiteModel.InvalidModelFile", true, 1);
}

TEST(LanguageDetectionModelTest, ReliableLanguageDetermination) {
  base::HistogramTester histogram_tester;
  base::File file = GetValidModelFile();
  LanguageDetectionModel language_detection_model;
  language_detection_model.UpdateWithFile(std::move(file));
  EXPECT_TRUE(language_detection_model.IsAvailable());

  bool is_prediction_reliable;
  float model_reliability_score = 0.0;
  std::string predicted_language;
  std::u16string contents = u"This is a page apparently written in English.";
  std::string language = language_detection_model.DeterminePageLanguage(
      std::string("ja"), std::string(), contents, &predicted_language,
      &is_prediction_reliable, model_reliability_score);
  EXPECT_TRUE(is_prediction_reliable);
  EXPECT_EQ("en", predicted_language);
  EXPECT_EQ(translate::kUnknownLanguageCode, language);
  histogram_tester.ExpectUniqueSample(
      "LanguageDetection.TFLite.DidAttemptDetection", true, 1);
}

TEST(LanguageDetectionModelTest, UnreliableLanguageDetermination) {
  base::HistogramTester histogram_tester;
  base::File file = GetValidModelFile();
  LanguageDetectionModel language_detection_model;
  language_detection_model.UpdateWithFile(std::move(file));
  EXPECT_TRUE(language_detection_model.IsAvailable());

  bool is_prediction_reliable;
  float model_reliability_score = 0.0;
  std::string predicted_language;
  std::u16string contents = u"e";
  std::string language = language_detection_model.DeterminePageLanguage(
      std::string("ja"), std::string(), contents, &predicted_language,
      &is_prediction_reliable, model_reliability_score);
  EXPECT_FALSE(is_prediction_reliable);
  EXPECT_EQ(translate::kUnknownLanguageCode, predicted_language);
  // Rely on the provided language code if the mode is unreliable.
  EXPECT_EQ("ja", language);
  histogram_tester.ExpectUniqueSample(
      "LanguageDetection.TFLite.DidAttemptDetection", true, 1);
}

TEST(LanguageDetectionModelTest, LongTextLanguageDetemination) {
  base::HistogramTester histogram_tester;
  base::File file = GetValidModelFile();
  LanguageDetectionModel language_detection_model;
  language_detection_model.UpdateWithFile(std::move(file));
  EXPECT_TRUE(language_detection_model.IsAvailable());

  bool is_prediction_reliable;
  float model_reliability_score = 0.0;
  std::string predicted_language;
  const char* const zh_content_string =
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "对于要提交的图书 我确认 我是版权所有者或已得到版权所有者的授权 "
      "要更改您的国家 地区 请在此表的最上端更改您的"
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "对于要提交的图书 我确认 我是版权所有者或已得到版权所有者的授权 "
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "对于要提交的图书 我确认 我是版权所有者或已得到版权所有者的授权 "
      "要更改您的国家 地区 请在此表的最上端更改您的"
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "对于要提交的图书 我确认 我是版权所有者或已得到版权所有者的授权 "
      "要更改您的国家 地区 请在此表的最上端更改您的"
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "对于要提交的图书 我确认 我是版权所有者或已得到版权所有者的授权 "
      "要更改您的国家 地区 请在此表的最上端更改您的"
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "对于要提交的图书 我确认 我是版权所有者或已得到版权所有者的授权 "
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "对于要提交的图书 我确认 我是版权所有者或已得到版权所有者的授权 "
      "要更改您的国家 地区 请在此表的最上端更改您的"
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "对于要提交的图书 我确认 我是版权所有者或已得到版权所有者的授权 "
      "要更改您的国家 地区 请在此表的最上端更改您的"
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "要更改您的国家 地区 请在此表的最上端更改您的"
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "对于要提交的图书 我确认 我是版权所有者或已得到版权所有者的授权 "
      "要更改您的国家 地区 请在此表的最上端更改您的"
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "对于要提交的图书 我确认 我是版权所有者或已得到版权所有者的授权 "
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "对于要提交的图书 我确认 我是版权所有者或已得到版权所有者的授权 "
      "要更改您的国家 地区 请在此表的最上端更改您的"
      "This is a page apparently written in English."
      "This is a page apparently written in English."
      "This is a page apparently written in English."
      "要更改您的国家 地区 请在此表的最上端更改您的"
      "产品的简报和公告 提交该申请后无法进行更改 请确认您的选择是正确的 "
      "要更改您的国家 地区 请在此表的最上端更改您的";

  std::u16string contents = base::UTF8ToUTF16(zh_content_string);
  EXPECT_GE(contents.length(), 250u * 3u);
  std::string language = language_detection_model.DeterminePageLanguage(
      std::string("ja"), std::string(), contents, &predicted_language,
      &is_prediction_reliable, model_reliability_score);
  EXPECT_TRUE(is_prediction_reliable);
  EXPECT_EQ("zh-CN", predicted_language);
  EXPECT_EQ(translate::kUnknownLanguageCode, language);
  histogram_tester.ExpectUniqueSample(
      "LanguageDetection.TFLite.DidAttemptDetection", true, 1);
}

}  // namespace translate