thirdparty/rocksdb/env/env_basic_test.cc - nifi-minifi-cpp - Git at Google

 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

 #include <memory>
 #include <string>
 #include <vector>
 #include <algorithm>

 #include "env/mock_env.h"
 #include "rocksdb/env.h"
 #include "rocksdb/utilities/object_registry.h"
 #include "util/testharness.h"

 namespace rocksdb {

 // Normalizes trivial differences across Envs such that these test cases can
 // run on all Envs.
 class NormalizingEnvWrapper : public EnvWrapper {
  public:
   explicit NormalizingEnvWrapper(Env* base) : EnvWrapper(base) {}

   // Removes . and .. from directory listing
   virtual Status GetChildren(const std::string& dir,
                              std::vector<std::string>* result) override {
     Status status = EnvWrapper::GetChildren(dir, result);
     if (status.ok()) {
       result->erase(std::remove_if(result->begin(), result->end(),
                                    [](const std::string& s) {
                                      return s == "." || s == "..";
                                    }),
                     result->end());
     }
     return status;
   }

   // Removes . and .. from directory listing
   virtual Status GetChildrenFileAttributes(
       const std::string& dir, std::vector<FileAttributes>* result) override {
     Status status = EnvWrapper::GetChildrenFileAttributes(dir, result);
     if (status.ok()) {
       result->erase(std::remove_if(result->begin(), result->end(),
                                    [](const FileAttributes& fa) {
                                      return fa.name == "." || fa.name == "..";
                                    }),
                     result->end());
     }
     return status;
   }
 };

 class EnvBasicTestWithParam : public testing::Test,
                               public ::testing::WithParamInterface<Env*> {
  public:
   Env* env_;
   const EnvOptions soptions_;
   std::string test_dir_;

   EnvBasicTestWithParam() : env_(GetParam()) {
     test_dir_ = test::TmpDir(env_) + "/env_basic_test";
   }

   void SetUp() {
     env_->CreateDirIfMissing(test_dir_);
   }

   void TearDown() {
     std::vector<std::string> files;
     env_->GetChildren(test_dir_, &files);
     for (const auto& file : files) {
       // don't know whether it's file or directory, try both. The tests must
       // only create files or empty directories, so one must succeed, else the
       // directory's corrupted.
       Status s = env_->DeleteFile(test_dir_ + "/" + file);
       if (!s.ok()) {
         ASSERT_OK(env_->DeleteDir(test_dir_ + "/" + file));
       }
     }
   }
 };

 class EnvMoreTestWithParam : public EnvBasicTestWithParam {};

 static std::unique_ptr<Env> def_env(new NormalizingEnvWrapper(Env::Default()));
 INSTANTIATE_TEST_CASE_P(EnvDefault, EnvBasicTestWithParam,
                         ::testing::Values(def_env.get()));
 INSTANTIATE_TEST_CASE_P(EnvDefault, EnvMoreTestWithParam,
                         ::testing::Values(def_env.get()));

 static std::unique_ptr<Env> mock_env(new MockEnv(Env::Default()));
 INSTANTIATE_TEST_CASE_P(MockEnv, EnvBasicTestWithParam,
                         ::testing::Values(mock_env.get()));
 #ifndef ROCKSDB_LITE
 static std::unique_ptr<Env> mem_env(NewMemEnv(Env::Default()));
 INSTANTIATE_TEST_CASE_P(MemEnv, EnvBasicTestWithParam,
                         ::testing::Values(mem_env.get()));

 namespace {

 // Returns a vector of 0 or 1 Env*, depending whether an Env is registered for
 // TEST_ENV_URI.
 //
 // The purpose of returning an empty vector (instead of nullptr) is that gtest
 // ValuesIn() will skip running tests when given an empty collection.
 std::vector<Env*> GetCustomEnvs() {
   static Env* custom_env;
   static std::unique_ptr<Env> custom_env_guard;
   static bool init = false;
   if (!init) {
     init = true;
     const char* uri = getenv("TEST_ENV_URI");
     if (uri != nullptr) {
       custom_env = NewCustomObject<Env>(uri, &custom_env_guard);
     }
   }

   std::vector<Env*> res;
   if (custom_env != nullptr) {
     res.emplace_back(custom_env);
   }
   return res;
 }

 }  // anonymous namespace

 INSTANTIATE_TEST_CASE_P(CustomEnv, EnvBasicTestWithParam,
                         ::testing::ValuesIn(GetCustomEnvs()));

 INSTANTIATE_TEST_CASE_P(CustomEnv, EnvMoreTestWithParam,
                         ::testing::ValuesIn(GetCustomEnvs()));

 #endif  // ROCKSDB_LITE

 TEST_P(EnvBasicTestWithParam, Basics) {
   uint64_t file_size;
   unique_ptr<WritableFile> writable_file;
   std::vector<std::string> children;

   // Check that the directory is empty.
   ASSERT_EQ(Status::NotFound(), env_->FileExists(test_dir_ + "/non_existent"));
   ASSERT_TRUE(!env_->GetFileSize(test_dir_ + "/non_existent", &file_size).ok());
   ASSERT_OK(env_->GetChildren(test_dir_, &children));
   ASSERT_EQ(0U, children.size());

   // Create a file.
   ASSERT_OK(env_->NewWritableFile(test_dir_ + "/f", &writable_file, soptions_));
   ASSERT_OK(writable_file->Close());
   writable_file.reset();

   // Check that the file exists.
   ASSERT_OK(env_->FileExists(test_dir_ + "/f"));
   ASSERT_OK(env_->GetFileSize(test_dir_ + "/f", &file_size));
   ASSERT_EQ(0U, file_size);
   ASSERT_OK(env_->GetChildren(test_dir_, &children));
   ASSERT_EQ(1U, children.size());
   ASSERT_EQ("f", children[0]);
   ASSERT_OK(env_->DeleteFile(test_dir_ + "/f"));

   // Write to the file.
   ASSERT_OK(
       env_->NewWritableFile(test_dir_ + "/f1", &writable_file, soptions_));
   ASSERT_OK(writable_file->Append("abc"));
   ASSERT_OK(writable_file->Close());
   writable_file.reset();
   ASSERT_OK(
       env_->NewWritableFile(test_dir_ + "/f2", &writable_file, soptions_));
   ASSERT_OK(writable_file->Close());
   writable_file.reset();

   // Check for expected size.
   ASSERT_OK(env_->GetFileSize(test_dir_ + "/f1", &file_size));
   ASSERT_EQ(3U, file_size);

   // Check that renaming works.
   ASSERT_TRUE(
       !env_->RenameFile(test_dir_ + "/non_existent", test_dir_ + "/g").ok());
   ASSERT_OK(env_->RenameFile(test_dir_ + "/f1", test_dir_ + "/g"));
   ASSERT_EQ(Status::NotFound(), env_->FileExists(test_dir_ + "/f1"));
   ASSERT_OK(env_->FileExists(test_dir_ + "/g"));
   ASSERT_OK(env_->GetFileSize(test_dir_ + "/g", &file_size));
   ASSERT_EQ(3U, file_size);

   // Check that renaming overwriting works
   ASSERT_OK(env_->RenameFile(test_dir_ + "/f2", test_dir_ + "/g"));
   ASSERT_OK(env_->GetFileSize(test_dir_ + "/g", &file_size));
   ASSERT_EQ(0U, file_size);

   // Check that opening non-existent file fails.
   unique_ptr<SequentialFile> seq_file;
   unique_ptr<RandomAccessFile> rand_file;
   ASSERT_TRUE(!env_->NewSequentialFile(test_dir_ + "/non_existent", &seq_file,
                                        soptions_)
                    .ok());
   ASSERT_TRUE(!seq_file);
   ASSERT_TRUE(!env_->NewRandomAccessFile(test_dir_ + "/non_existent",
                                          &rand_file, soptions_)
                    .ok());
   ASSERT_TRUE(!rand_file);

   // Check that deleting works.
   ASSERT_TRUE(!env_->DeleteFile(test_dir_ + "/non_existent").ok());
   ASSERT_OK(env_->DeleteFile(test_dir_ + "/g"));
   ASSERT_EQ(Status::NotFound(), env_->FileExists(test_dir_ + "/g"));
   ASSERT_OK(env_->GetChildren(test_dir_, &children));
   ASSERT_EQ(0U, children.size());
   ASSERT_TRUE(
       env_->GetChildren(test_dir_ + "/non_existent", &children).IsNotFound());
 }

 TEST_P(EnvBasicTestWithParam, ReadWrite) {
   unique_ptr<WritableFile> writable_file;
   unique_ptr<SequentialFile> seq_file;
   unique_ptr<RandomAccessFile> rand_file;
   Slice result;
   char scratch[100];

   ASSERT_OK(env_->NewWritableFile(test_dir_ + "/f", &writable_file, soptions_));
   ASSERT_OK(writable_file->Append("hello "));
   ASSERT_OK(writable_file->Append("world"));
   ASSERT_OK(writable_file->Close());
   writable_file.reset();

   // Read sequentially.
   ASSERT_OK(env_->NewSequentialFile(test_dir_ + "/f", &seq_file, soptions_));
   ASSERT_OK(seq_file->Read(5, &result, scratch));  // Read "hello".
   ASSERT_EQ(0, result.compare("hello"));
   ASSERT_OK(seq_file->Skip(1));
   ASSERT_OK(seq_file->Read(1000, &result, scratch));  // Read "world".
   ASSERT_EQ(0, result.compare("world"));
   ASSERT_OK(seq_file->Read(1000, &result, scratch));  // Try reading past EOF.
   ASSERT_EQ(0U, result.size());
   ASSERT_OK(seq_file->Skip(100));  // Try to skip past end of file.
   ASSERT_OK(seq_file->Read(1000, &result, scratch));
   ASSERT_EQ(0U, result.size());

   // Random reads.
   ASSERT_OK(env_->NewRandomAccessFile(test_dir_ + "/f", &rand_file, soptions_));
   ASSERT_OK(rand_file->Read(6, 5, &result, scratch));  // Read "world".
   ASSERT_EQ(0, result.compare("world"));
   ASSERT_OK(rand_file->Read(0, 5, &result, scratch));  // Read "hello".
   ASSERT_EQ(0, result.compare("hello"));
   ASSERT_OK(rand_file->Read(10, 100, &result, scratch));  // Read "d".
   ASSERT_EQ(0, result.compare("d"));

   // Too high offset.
   ASSERT_TRUE(rand_file->Read(1000, 5, &result, scratch).ok());
 }

 TEST_P(EnvBasicTestWithParam, Misc) {
   unique_ptr<WritableFile> writable_file;
   ASSERT_OK(env_->NewWritableFile(test_dir_ + "/b", &writable_file, soptions_));

   // These are no-ops, but we test they return success.
   ASSERT_OK(writable_file->Sync());
   ASSERT_OK(writable_file->Flush());
   ASSERT_OK(writable_file->Close());
   writable_file.reset();
 }

 TEST_P(EnvBasicTestWithParam, LargeWrite) {
   const size_t kWriteSize = 300 * 1024;
   char* scratch = new char[kWriteSize * 2];

   std::string write_data;
   for (size_t i = 0; i < kWriteSize; ++i) {
     write_data.append(1, static_cast<char>(i));
   }

   unique_ptr<WritableFile> writable_file;
   ASSERT_OK(env_->NewWritableFile(test_dir_ + "/f", &writable_file, soptions_));
   ASSERT_OK(writable_file->Append("foo"));
   ASSERT_OK(writable_file->Append(write_data));
   ASSERT_OK(writable_file->Close());
   writable_file.reset();

   unique_ptr<SequentialFile> seq_file;
   Slice result;
   ASSERT_OK(env_->NewSequentialFile(test_dir_ + "/f", &seq_file, soptions_));
   ASSERT_OK(seq_file->Read(3, &result, scratch));  // Read "foo".
   ASSERT_EQ(0, result.compare("foo"));

   size_t read = 0;
   std::string read_data;
   while (read < kWriteSize) {
     ASSERT_OK(seq_file->Read(kWriteSize - read, &result, scratch));
     read_data.append(result.data(), result.size());
     read += result.size();
   }
   ASSERT_TRUE(write_data == read_data);
   delete [] scratch;
 }

 TEST_P(EnvMoreTestWithParam, GetModTime) {
   ASSERT_OK(env_->CreateDirIfMissing(test_dir_ + "/dir1"));
   uint64_t mtime1 = 0x0;
   ASSERT_OK(env_->GetFileModificationTime(test_dir_ + "/dir1", &mtime1));
 }

 TEST_P(EnvMoreTestWithParam, MakeDir) {
   ASSERT_OK(env_->CreateDir(test_dir_ + "/j"));
   ASSERT_OK(env_->FileExists(test_dir_ + "/j"));
   std::vector<std::string> children;
   env_->GetChildren(test_dir_, &children);
   ASSERT_EQ(1U, children.size());
   // fail because file already exists
   ASSERT_TRUE(!env_->CreateDir(test_dir_ + "/j").ok());
   ASSERT_OK(env_->CreateDirIfMissing(test_dir_ + "/j"));
   ASSERT_OK(env_->DeleteDir(test_dir_ + "/j"));
   ASSERT_EQ(Status::NotFound(), env_->FileExists(test_dir_ + "/j"));
 }

 TEST_P(EnvMoreTestWithParam, GetChildren) {
   // empty folder returns empty vector
   std::vector<std::string> children;
   std::vector<Env::FileAttributes> childAttr;
   ASSERT_OK(env_->CreateDirIfMissing(test_dir_));
   ASSERT_OK(env_->GetChildren(test_dir_, &children));
   ASSERT_OK(env_->FileExists(test_dir_));
   ASSERT_OK(env_->GetChildrenFileAttributes(test_dir_, &childAttr));
   ASSERT_EQ(0U, children.size());
   ASSERT_EQ(0U, childAttr.size());

   // folder with contents returns relative path to test dir
   ASSERT_OK(env_->CreateDirIfMissing(test_dir_ + "/niu"));
   ASSERT_OK(env_->CreateDirIfMissing(test_dir_ + "/you"));
   ASSERT_OK(env_->CreateDirIfMissing(test_dir_ + "/guo"));
   ASSERT_OK(env_->GetChildren(test_dir_, &children));
   ASSERT_OK(env_->GetChildrenFileAttributes(test_dir_, &childAttr));
   ASSERT_EQ(3U, children.size());
   ASSERT_EQ(3U, childAttr.size());
   for (auto each : children) {
     env_->DeleteDir(test_dir_ + "/" + each);
   }  // necessary for default POSIX env

   // non-exist directory returns IOError
   ASSERT_OK(env_->DeleteDir(test_dir_));
   ASSERT_TRUE(!env_->FileExists(test_dir_).ok());
   ASSERT_TRUE(!env_->GetChildren(test_dir_, &children).ok());
   ASSERT_TRUE(!env_->GetChildrenFileAttributes(test_dir_, &childAttr).ok());

   // if dir is a file, returns IOError
   ASSERT_OK(env_->CreateDir(test_dir_));
   unique_ptr<WritableFile> writable_file;
   ASSERT_OK(
       env_->NewWritableFile(test_dir_ + "/file", &writable_file, soptions_));
   ASSERT_OK(writable_file->Close());
   writable_file.reset();
   ASSERT_TRUE(!env_->GetChildren(test_dir_ + "/file", &children).ok());
   ASSERT_EQ(0U, children.size());
 }

 }  // namespace rocksdb
 int main(int argc, char** argv) {
   ::testing::InitGoogleTest(&argc, argv);
   return RUN_ALL_TESTS();
 }
	// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file. See the AUTHORS file for names of contributors.

	#include <memory>
	#include <string>
	#include <vector>
	#include <algorithm>

	#include "env/mock_env.h"
	#include "rocksdb/env.h"
	#include "rocksdb/utilities/object_registry.h"
	#include "util/testharness.h"

	namespace rocksdb {

	// Normalizes trivial differences across Envs such that these test cases can
	// run on all Envs.
	class NormalizingEnvWrapper : public EnvWrapper {
	public:
	explicit NormalizingEnvWrapper(Env* base) : EnvWrapper(base) {}

	// Removes . and .. from directory listing
	virtual Status GetChildren(const std::string& dir,
	std::vector<std::string>* result) override {
	Status status = EnvWrapper::GetChildren(dir, result);
	if (status.ok()) {
	result->erase(std::remove_if(result->begin(), result->end(),
	[](const std::string& s) {
	return s == "." \|\| s == "..";
	}),
	result->end());
	}
	return status;
	}

	// Removes . and .. from directory listing
	virtual Status GetChildrenFileAttributes(
	const std::string& dir, std::vector<FileAttributes>* result) override {
	Status status = EnvWrapper::GetChildrenFileAttributes(dir, result);
	if (status.ok()) {
	result->erase(std::remove_if(result->begin(), result->end(),
	[](const FileAttributes& fa) {
	return fa.name == "." \|\| fa.name == "..";
	}),
	result->end());
	}
	return status;
	}
	};

	class EnvBasicTestWithParam : public testing::Test,
	public ::testing::WithParamInterface<Env*> {
	public:
	Env* env_;
	const EnvOptions soptions_;
	std::string test_dir_;

	EnvBasicTestWithParam() : env_(GetParam()) {
	test_dir_ = test::TmpDir(env_) + "/env_basic_test";
	}

	void SetUp() {
	env_->CreateDirIfMissing(test_dir_);
	}

	void TearDown() {
	std::vector<std::string> files;
	env_->GetChildren(test_dir_, &files);
	for (const auto& file : files) {
	// don't know whether it's file or directory, try both. The tests must
	// only create files or empty directories, so one must succeed, else the
	// directory's corrupted.
	Status s = env_->DeleteFile(test_dir_ + "/" + file);
	if (!s.ok()) {
	ASSERT_OK(env_->DeleteDir(test_dir_ + "/" + file));
	}
	}
	}
	};

	class EnvMoreTestWithParam : public EnvBasicTestWithParam {};

	static std::unique_ptr<Env> def_env(new NormalizingEnvWrapper(Env::Default()));
	INSTANTIATE_TEST_CASE_P(EnvDefault, EnvBasicTestWithParam,
	::testing::Values(def_env.get()));
	INSTANTIATE_TEST_CASE_P(EnvDefault, EnvMoreTestWithParam,
	::testing::Values(def_env.get()));

	static std::unique_ptr<Env> mock_env(new MockEnv(Env::Default()));
	INSTANTIATE_TEST_CASE_P(MockEnv, EnvBasicTestWithParam,
	::testing::Values(mock_env.get()));
	#ifndef ROCKSDB_LITE
	static std::unique_ptr<Env> mem_env(NewMemEnv(Env::Default()));
	INSTANTIATE_TEST_CASE_P(MemEnv, EnvBasicTestWithParam,
	::testing::Values(mem_env.get()));

	namespace {

	// Returns a vector of 0 or 1 Env*, depending whether an Env is registered for
	// TEST_ENV_URI.
	//
	// The purpose of returning an empty vector (instead of nullptr) is that gtest
	// ValuesIn() will skip running tests when given an empty collection.
	std::vector<Env*> GetCustomEnvs() {
	static Env* custom_env;
	static std::unique_ptr<Env> custom_env_guard;
	static bool init = false;
	if (!init) {
	init = true;
	const char* uri = getenv("TEST_ENV_URI");
	if (uri != nullptr) {
	custom_env = NewCustomObject<Env>(uri, &custom_env_guard);
	}
	}

	std::vector<Env*> res;
	if (custom_env != nullptr) {
	res.emplace_back(custom_env);
	}
	return res;
	}

	} // anonymous namespace

	INSTANTIATE_TEST_CASE_P(CustomEnv, EnvBasicTestWithParam,
	::testing::ValuesIn(GetCustomEnvs()));

	INSTANTIATE_TEST_CASE_P(CustomEnv, EnvMoreTestWithParam,
	::testing::ValuesIn(GetCustomEnvs()));

	#endif // ROCKSDB_LITE

	TEST_P(EnvBasicTestWithParam, Basics) {
	uint64_t file_size;
	unique_ptr<WritableFile> writable_file;
	std::vector<std::string> children;

	// Check that the directory is empty.
	ASSERT_EQ(Status::NotFound(), env_->FileExists(test_dir_ + "/non_existent"));
	ASSERT_TRUE(!env_->GetFileSize(test_dir_ + "/non_existent", &file_size).ok());
	ASSERT_OK(env_->GetChildren(test_dir_, &children));
	ASSERT_EQ(0U, children.size());

	// Create a file.
	ASSERT_OK(env_->NewWritableFile(test_dir_ + "/f", &writable_file, soptions_));
	ASSERT_OK(writable_file->Close());
	writable_file.reset();

	// Check that the file exists.
	ASSERT_OK(env_->FileExists(test_dir_ + "/f"));
	ASSERT_OK(env_->GetFileSize(test_dir_ + "/f", &file_size));
	ASSERT_EQ(0U, file_size);
	ASSERT_OK(env_->GetChildren(test_dir_, &children));
	ASSERT_EQ(1U, children.size());
	ASSERT_EQ("f", children[0]);
	ASSERT_OK(env_->DeleteFile(test_dir_ + "/f"));

	// Write to the file.
	ASSERT_OK(
	env_->NewWritableFile(test_dir_ + "/f1", &writable_file, soptions_));
	ASSERT_OK(writable_file->Append("abc"));
	ASSERT_OK(writable_file->Close());
	writable_file.reset();
	ASSERT_OK(
	env_->NewWritableFile(test_dir_ + "/f2", &writable_file, soptions_));
	ASSERT_OK(writable_file->Close());
	writable_file.reset();

	// Check for expected size.
	ASSERT_OK(env_->GetFileSize(test_dir_ + "/f1", &file_size));
	ASSERT_EQ(3U, file_size);

	// Check that renaming works.
	ASSERT_TRUE(
	!env_->RenameFile(test_dir_ + "/non_existent", test_dir_ + "/g").ok());
	ASSERT_OK(env_->RenameFile(test_dir_ + "/f1", test_dir_ + "/g"));
	ASSERT_EQ(Status::NotFound(), env_->FileExists(test_dir_ + "/f1"));
	ASSERT_OK(env_->FileExists(test_dir_ + "/g"));
	ASSERT_OK(env_->GetFileSize(test_dir_ + "/g", &file_size));
	ASSERT_EQ(3U, file_size);

	// Check that renaming overwriting works
	ASSERT_OK(env_->RenameFile(test_dir_ + "/f2", test_dir_ + "/g"));
	ASSERT_OK(env_->GetFileSize(test_dir_ + "/g", &file_size));
	ASSERT_EQ(0U, file_size);

	// Check that opening non-existent file fails.
	unique_ptr<SequentialFile> seq_file;
	unique_ptr<RandomAccessFile> rand_file;
	ASSERT_TRUE(!env_->NewSequentialFile(test_dir_ + "/non_existent", &seq_file,
	soptions_)
	.ok());
	ASSERT_TRUE(!seq_file);
	ASSERT_TRUE(!env_->NewRandomAccessFile(test_dir_ + "/non_existent",
	&rand_file, soptions_)
	.ok());
	ASSERT_TRUE(!rand_file);

	// Check that deleting works.
	ASSERT_TRUE(!env_->DeleteFile(test_dir_ + "/non_existent").ok());
	ASSERT_OK(env_->DeleteFile(test_dir_ + "/g"));
	ASSERT_EQ(Status::NotFound(), env_->FileExists(test_dir_ + "/g"));
	ASSERT_OK(env_->GetChildren(test_dir_, &children));
	ASSERT_EQ(0U, children.size());
	ASSERT_TRUE(
	env_->GetChildren(test_dir_ + "/non_existent", &children).IsNotFound());
	}

	TEST_P(EnvBasicTestWithParam, ReadWrite) {
	unique_ptr<WritableFile> writable_file;
	unique_ptr<SequentialFile> seq_file;
	unique_ptr<RandomAccessFile> rand_file;
	Slice result;
	char scratch[100];

	ASSERT_OK(env_->NewWritableFile(test_dir_ + "/f", &writable_file, soptions_));
	ASSERT_OK(writable_file->Append("hello "));
	ASSERT_OK(writable_file->Append("world"));
	ASSERT_OK(writable_file->Close());
	writable_file.reset();

	// Read sequentially.
	ASSERT_OK(env_->NewSequentialFile(test_dir_ + "/f", &seq_file, soptions_));
	ASSERT_OK(seq_file->Read(5, &result, scratch)); // Read "hello".
	ASSERT_EQ(0, result.compare("hello"));
	ASSERT_OK(seq_file->Skip(1));
	ASSERT_OK(seq_file->Read(1000, &result, scratch)); // Read "world".
	ASSERT_EQ(0, result.compare("world"));
	ASSERT_OK(seq_file->Read(1000, &result, scratch)); // Try reading past EOF.
	ASSERT_EQ(0U, result.size());
	ASSERT_OK(seq_file->Skip(100)); // Try to skip past end of file.
	ASSERT_OK(seq_file->Read(1000, &result, scratch));
	ASSERT_EQ(0U, result.size());

	// Random reads.
	ASSERT_OK(env_->NewRandomAccessFile(test_dir_ + "/f", &rand_file, soptions_));
	ASSERT_OK(rand_file->Read(6, 5, &result, scratch)); // Read "world".
	ASSERT_EQ(0, result.compare("world"));
	ASSERT_OK(rand_file->Read(0, 5, &result, scratch)); // Read "hello".
	ASSERT_EQ(0, result.compare("hello"));
	ASSERT_OK(rand_file->Read(10, 100, &result, scratch)); // Read "d".
	ASSERT_EQ(0, result.compare("d"));

	// Too high offset.
	ASSERT_TRUE(rand_file->Read(1000, 5, &result, scratch).ok());
	}

	TEST_P(EnvBasicTestWithParam, Misc) {
	unique_ptr<WritableFile> writable_file;
	ASSERT_OK(env_->NewWritableFile(test_dir_ + "/b", &writable_file, soptions_));

	// These are no-ops, but we test they return success.
	ASSERT_OK(writable_file->Sync());
	ASSERT_OK(writable_file->Flush());
	ASSERT_OK(writable_file->Close());
	writable_file.reset();
	}

	TEST_P(EnvBasicTestWithParam, LargeWrite) {
	const size_t kWriteSize = 300 * 1024;
	char* scratch = new char[kWriteSize * 2];

	std::string write_data;
	for (size_t i = 0; i < kWriteSize; ++i) {
	write_data.append(1, static_cast<char>(i));
	}

	unique_ptr<WritableFile> writable_file;
	ASSERT_OK(env_->NewWritableFile(test_dir_ + "/f", &writable_file, soptions_));
	ASSERT_OK(writable_file->Append("foo"));
	ASSERT_OK(writable_file->Append(write_data));
	ASSERT_OK(writable_file->Close());
	writable_file.reset();

	unique_ptr<SequentialFile> seq_file;
	Slice result;
	ASSERT_OK(env_->NewSequentialFile(test_dir_ + "/f", &seq_file, soptions_));
	ASSERT_OK(seq_file->Read(3, &result, scratch)); // Read "foo".
	ASSERT_EQ(0, result.compare("foo"));

	size_t read = 0;
	std::string read_data;
	while (read < kWriteSize) {
	ASSERT_OK(seq_file->Read(kWriteSize - read, &result, scratch));
	read_data.append(result.data(), result.size());
	read += result.size();
	}
	ASSERT_TRUE(write_data == read_data);
	delete [] scratch;
	}

	TEST_P(EnvMoreTestWithParam, GetModTime) {
	ASSERT_OK(env_->CreateDirIfMissing(test_dir_ + "/dir1"));
	uint64_t mtime1 = 0x0;
	ASSERT_OK(env_->GetFileModificationTime(test_dir_ + "/dir1", &mtime1));
	}

	TEST_P(EnvMoreTestWithParam, MakeDir) {
	ASSERT_OK(env_->CreateDir(test_dir_ + "/j"));
	ASSERT_OK(env_->FileExists(test_dir_ + "/j"));
	std::vector<std::string> children;
	env_->GetChildren(test_dir_, &children);
	ASSERT_EQ(1U, children.size());
	// fail because file already exists
	ASSERT_TRUE(!env_->CreateDir(test_dir_ + "/j").ok());
	ASSERT_OK(env_->CreateDirIfMissing(test_dir_ + "/j"));
	ASSERT_OK(env_->DeleteDir(test_dir_ + "/j"));
	ASSERT_EQ(Status::NotFound(), env_->FileExists(test_dir_ + "/j"));
	}

	TEST_P(EnvMoreTestWithParam, GetChildren) {
	// empty folder returns empty vector
	std::vector<std::string> children;
	std::vector<Env::FileAttributes> childAttr;
	ASSERT_OK(env_->CreateDirIfMissing(test_dir_));
	ASSERT_OK(env_->GetChildren(test_dir_, &children));
	ASSERT_OK(env_->FileExists(test_dir_));
	ASSERT_OK(env_->GetChildrenFileAttributes(test_dir_, &childAttr));
	ASSERT_EQ(0U, children.size());
	ASSERT_EQ(0U, childAttr.size());

	// folder with contents returns relative path to test dir
	ASSERT_OK(env_->CreateDirIfMissing(test_dir_ + "/niu"));
	ASSERT_OK(env_->CreateDirIfMissing(test_dir_ + "/you"));
	ASSERT_OK(env_->CreateDirIfMissing(test_dir_ + "/guo"));
	ASSERT_OK(env_->GetChildren(test_dir_, &children));
	ASSERT_OK(env_->GetChildrenFileAttributes(test_dir_, &childAttr));
	ASSERT_EQ(3U, children.size());
	ASSERT_EQ(3U, childAttr.size());
	for (auto each : children) {
	env_->DeleteDir(test_dir_ + "/" + each);
	} // necessary for default POSIX env

	// non-exist directory returns IOError
	ASSERT_OK(env_->DeleteDir(test_dir_));
	ASSERT_TRUE(!env_->FileExists(test_dir_).ok());
	ASSERT_TRUE(!env_->GetChildren(test_dir_, &children).ok());
	ASSERT_TRUE(!env_->GetChildrenFileAttributes(test_dir_, &childAttr).ok());

	// if dir is a file, returns IOError
	ASSERT_OK(env_->CreateDir(test_dir_));
	unique_ptr<WritableFile> writable_file;
	ASSERT_OK(
	env_->NewWritableFile(test_dir_ + "/file", &writable_file, soptions_));
	ASSERT_OK(writable_file->Close());
	writable_file.reset();
	ASSERT_TRUE(!env_->GetChildren(test_dir_ + "/file", &children).ok());
	ASSERT_EQ(0U, children.size());
	}

	} // namespace rocksdb
	int main(int argc, char** argv) {
	::testing::InitGoogleTest(&argc, argv);
	return RUN_ALL_TESTS();
	}