[sensors] Ambient light sensor implementation for ChromeOS and Linux.

device/generic_sensor/iio/sensor_reader_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 "base/files/file_util.h"
+#include "base/files/scoped_temp_dir.h"
+#include "base/strings/string_number_conversions.h"
+
+#include "device/generic_sensor/iio/platform_sensor_utils_iio.h"
+#include "device/generic_sensor/iio/sensor_data_iio.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace device {
+
+namespace {
+
+const base::FilePath::CharType* kBaseSensorFilesDirTest =
+    FILE_PATH_LITERAL("/tmp/.org.chromium.generic_sensor_test/");
+
+const base::FilePath::CharType* kDevice0Dir = FILE_PATH_LITERAL("device0");
+
+const char* kSensorFileNameTest1 = "sensor_data1";

[Mikhail, 2016/10/18 11:37:21]

nit:
const char kSensorFileNameTest1[]

[maksims (do not use this acc), 2016/10/19 06:57:09]

Done.

+const char* kSensorFileNameTest2 = "sensor_data2";
+const char* kSensorFileNameTest3 = "sensor_data3";
+
+const char* kTestSensorFileNamesTest[][5] = {
+    {
+        kSensorFileNameTest1, "sensor1_input", "sensor1_raw_input", "sensor1",
+        "sensor1_data_raw",
+    },
+    {
+        "sensor2", kSensorFileNameTest2, "sensor2_raw_input", "sensor2_input",
+        "sensor2_data_raw",
+    },
+    {
+        "sensor3", "sensor3_input", "sensor3_raw_input", "sensor3_data_raw",
+        kSensorFileNameTest3,
+    },
+};
+
+void CreateFile(const base::FilePath& file) {
+  EXPECT_EQ(base::WriteFile(file, NULL, 0), 0);
+}
+
+void DeleteFile(const base::FilePath& file) {
+  EXPECT_TRUE(base::DeleteFile(file, false));
+}
+
+void WriteStringToFile(const base::FilePath& path,
+                       const base::StringPiece& str) {
+  int bytes_written = base::WriteFile(path, str.data(), str.size());
+  EXPECT_EQ(static_cast<size_t>(bytes_written), str.size());
+}
+
+}  // namespace
+
+class SensorReaderTest : public ::testing::Test {
+ public:
+  void SetUp() override {
+    base::FilePath path(kBaseSensorFilesDirTest);
+    base::FilePath sensors_dir = path.Append(kDevice0Dir);
+    ASSERT_TRUE(temp_dir_.Set(sensors_dir));
+  }
+
+  void TearDown() override {
+    // Delete //device0 folder.
+    ASSERT_TRUE(temp_dir_.Delete());
+    // Delete base folder.
+    base::FilePath path(kBaseSensorFilesDirTest);
+    ASSERT_TRUE(temp_dir_.Set(path));

[Mikhail, 2016/10/18 11:37:21]

CreateUniqueTempDir() API looks more appropriate here

[maksims (do not use this acc), 2016/10/19 06:57:09]

Why??? I have a dir which lookis like
/tmp/.org.chromium.generic_sensor_test/device0.
It is created in SetUp. And in order to delete both, I need to first remove
device0, take ownership of .org.chromium.generic_sensor_test and only then
delete .org.chromium.generic_sensor_test. 

+    ASSERT_TRUE(temp_dir_.Delete());
+  }
+
+  void InitSensorDataForTest(size_t rows, SensorDataIio* data) {
+    // Corresponds to maximum values in SensorReading.
+    // We must read only from up to three files. Thus - 3 sets of files
+    // should be fill in here.
+    const size_t max_rows = 3;
+    if (rows > 3)
+      rows = max_rows;
+
+    data->base_path_sensor_iio = kBaseSensorFilesDirTest;
+    for (size_t i = 0; i < rows; ++i) {
+      data->sensor_file_names[i] = &kTestSensorFileNamesTest[i][0];
+    }
+    data->sensor_file_names_cols = arraysize(*kTestSensorFileNamesTest);
+    data->sensor_file_names_rows = rows;
+  }
+
+  void CheckSensorDataFields(const SensorReading& data,
+                             std::string value1,

[Mikhail, 2016/10/18 11:37:21]

let's make it accept doubles

+                             std::string value2,
+                             std::string value3) {
+    EXPECT_EQ(value1, base::DoubleToString(data.values[0]));
+    EXPECT_EQ(value2, base::DoubleToString(data.values[1]));
+    EXPECT_EQ(value3, base::DoubleToString(data.values[2]));
+  }
+
+ protected:
+  base::ScopedTempDir temp_dir_;
+};
+
+TEST_F(SensorReaderTest, FileDoesNotExist) {
+  const char* kGiberishFiles[] = {"temp1", "temp2", "temp3", "temp4"};
+  const size_t rows = 3;
+  // Create some giberish files that we are not interested in.
+  base::FilePath sensors_dir = temp_dir_.GetPath();
+  for (unsigned int i = 0; i < arraysize(kGiberishFiles); ++i) {
+    base::FilePath some_file = sensors_dir.Append(kGiberishFiles[i]);
+    CreateFile(some_file);
+  }
+
+  SensorDataIio sensor_data;
+  InitSensorDataForTest(rows, &sensor_data);
+
+  std::unique_ptr<SensorReader> reader = SensorReader::Create(sensor_data);
+  EXPECT_FALSE(reader);
+}
+
+TEST_F(SensorReaderTest, ReadValueFromOneFile) {
+  const size_t rows = 1;
+  const std::string value1 = "20";
+  const std::string zero_value = "0";
+  // Get sensors dir, which looks like
+  // /tmp/.org.chromium.generic_sensor_test/device0
+  base::FilePath sensors_dir = temp_dir_.GetPath();
+  // Create a test sensor file, which must be found to be read from.
+  base::FilePath temp_sensor_file = sensors_dir.Append(kSensorFileNameTest1);
+  CreateFile(temp_sensor_file);
+
+  // Initialize sensor data for a reader.
+  SensorDataIio sensor_data;
+  InitSensorDataForTest(rows, &sensor_data);
+
+  std::unique_ptr<SensorReader> reader = SensorReader::Create(sensor_data);
+  EXPECT_TRUE(reader);
+
+  // Write a value to the file.
+  WriteStringToFile(temp_sensor_file, value1);
+
+  // Fill SensorReading's first field with read value. Other fields must
+  // be 0.
+  SensorReading reading;
+  EXPECT_TRUE(reader->ReadSensorReading(&reading));
+  CheckSensorDataFields(reading, value1, zero_value, zero_value);
+}
+
+TEST_F(SensorReaderTest, ReadValuesFromTwoFiles) {
+  const size_t rows = 2;
+  const std::string value1 = "20";
+  const std::string value2 = "50";
+  const std::string zero_value = "0";
+  // Get sensors dir, which looks like
+  // /tmp/.org.chromium.generic_sensor_test/device0
+  base::FilePath sensors_dir = temp_dir_.GetPath();
+  // Create a test sensor file, which must be found.
+  base::FilePath temp_sensor_file1 = sensors_dir.Append(kSensorFileNameTest1);
+  CreateFile(temp_sensor_file1);
+
+  // Create another test sensor file, which must be found.
+  base::FilePath temp_sensor_file2 = sensors_dir.Append(kSensorFileNameTest2);
+  CreateFile(temp_sensor_file2);
+
+  // Initialize sensor data for a reader.
+  SensorDataIio sensor_data;
+  InitSensorDataForTest(rows, &sensor_data);
+
+  std::unique_ptr<SensorReader> reader = SensorReader::Create(sensor_data);
+  EXPECT_TRUE(reader);
+
+  // Write a value to the file.
+  WriteStringToFile(temp_sensor_file1, value1);
+  WriteStringToFile(temp_sensor_file2, value2);
+
+  // Fill SensorReading's two first fields with read value. Last field must
+  // be 0.
+  SensorReading reading;
+  EXPECT_TRUE(reader->ReadSensorReading(&reading));
+  CheckSensorDataFields(reading, value1, value2, zero_value);
+}
+
+TEST_F(SensorReaderTest, ReadValuesFromThreeFilesAndFail) {
+  const size_t rows = 4;
+  const std::string value1 = "20";

[Mikhail, 2016/10/18 11:37:21]

double (and in other places)

[maksims (do not use this acc), 2016/10/19 06:57:09]

Done.

+  const std::string value2 = "50";
+  const std::string value3 = "80";
+  const std::string zero_value = "0";
+  // Get sensors dir, which looks like
+  // /tmp/.org.chromium.generic_sensor_test/device0
+  base::FilePath sensors_dir = temp_dir_.GetPath();
+  // Create a test sensor file, which must be found.
+  base::FilePath temp_sensor_file1 = sensors_dir.Append(kSensorFileNameTest1);
+  CreateFile(temp_sensor_file1);
+
+  // Create another test sensor file, which must be found.
+  base::FilePath temp_sensor_file2 = sensors_dir.Append(kSensorFileNameTest2);
+  CreateFile(temp_sensor_file2);
+
+  // Create third test sensor file, which must be found.
+  base::FilePath temp_sensor_file3 = sensors_dir.Append(kSensorFileNameTest3);
+  CreateFile(temp_sensor_file3);
+
+  // Initialize sensor data for a reader.
+  SensorDataIio sensor_data;
+  InitSensorDataForTest(rows, &sensor_data);
+
+  std::unique_ptr<SensorReader> reader = SensorReader::Create(sensor_data);
+  EXPECT_TRUE(reader);
+
+  // Write a value to the file.
+  WriteStringToFile(temp_sensor_file1, value1);

[Mikhail, 2016/10/18 11:37:21]

WriteReadingFieldToFile(file, double)

[maksims (do not use this acc), 2016/10/19 06:57:09]

Done.

+  WriteStringToFile(temp_sensor_file2, value2);
+  WriteStringToFile(temp_sensor_file3, value3);
+
+  // Fill SensorReading's values with data from files.
+  SensorReading reading;
+  EXPECT_TRUE(reader->ReadSensorReading(&reading));
+  CheckSensorDataFields(reading, value1, value2, value3);
+
+  SensorReading reading2;
+  DeleteFile(temp_sensor_file2);
+  EXPECT_FALSE(reader->ReadSensorReading(&reading2));
+  CheckSensorDataFields(reading2, zero_value, zero_value, zero_value);
+}
+
+TEST_F(SensorReaderTest, SensorReadFilesDoNotExist) {
+  const size_t rows = 3;
+  // Get sensors dir, which looks like
+  // /tmp/.org.chromium.generic_sensor_test/device0
+  base::FilePath sensors_dir = temp_dir_.GetPath();
+  // Create a test sensor file, which must be found. Other
+  // files will not be created and the test must fail to create a reader.
+  base::FilePath temp_sensor_file1 = sensors_dir.Append(kSensorFileNameTest1);
+  CreateFile(temp_sensor_file1);
+
+  // Initialize sensor data for a reader.
+  SensorDataIio sensor_data;
+  InitSensorDataForTest(rows, &sensor_data);
+
+  std::unique_ptr<SensorReader> reader = SensorReader::Create(sensor_data);
+  EXPECT_FALSE(reader);
+
+  // Create one more file. The reader mustn't be created as long as it
+  // expects three files to be found.
+  base::FilePath temp_sensor_file2 = sensors_dir.Append(kSensorFileNameTest2);
+  CreateFile(temp_sensor_file2);
+
+  reader.reset();
+  reader = SensorReader::Create(sensor_data);
+  EXPECT_FALSE(reader);
+
+  // Create last file.
+  base::FilePath temp_sensor_file3 = sensors_dir.Append(kSensorFileNameTest3);
+  CreateFile(temp_sensor_file3);
+
+  reader.reset();
+  reader = SensorReader::Create(sensor_data);
+  EXPECT_TRUE(reader);
+}
+
+}  // namespace device