Implement async verision of FileSystemFileUtil and in-memory file system for testing purposes.

webkit/chromeos/fileapi/memory_file_util_unittest.cc

+// Copyright (c) 2011 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/bind.h"
+#include "base/message_loop.h"
+#include "base/platform_file.h"
+#include "base/time.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "webkit/chromeos/fileapi/memory_file_util.h"
+
+namespace {
+const FilePath::CharType kRootPath[] = "/mnt/memory";
+const char kTestString[] = "A test string. A test string.";
+const char kTestStringLength = arraysize(kTestString) - 1;
+}  // namespace
+
+namespace fileapi {
+
+// This test is actually testing MemoryFileUtil — an async in-memory file
+// system, based on FileUtilAsync.
+class MemoryFileUtilTest : public testing::Test {
+ public:
+  MemoryFileUtilTest() {
+  }
+
+  void SetUp() {
+    file_util_.reset(new MemoryFileUtil(FilePath(kRootPath)));
+  }
+
+  MemoryFileUtil* file_util() {
+    return file_util_.get();
+  }
+
+  enum CallbackType {
+    CALLBACK_TYPE_ERROR,
+    CALLBACK_TYPE_STATUS,
+    CALLBACK_TYPE_GET_FILE_INFO,
+    CALLBACK_TYPE_OPEN,
+    CALLBACK_TYPE_READ_WRITE,
+    CALLBACK_TYPE_READ_DIRECTORY
+  };
+
+  struct CallbackStatus {
+    CallbackType type;
+    base::PlatformFileError result;
+    base::PlatformFileInfo file_info;
+    // This object should be deleted in the test code.
+    AsyncFileStream* file_stream;
+    int64 length;
+
+    // Following 4 fields only for ReadDirectory.
+    FileUtilAsync::FileList entries;
+    bool completed;
+    bool called_after_completed;
+    int called;
+  };
+
+  StatusCallback GetStatusCallback(int request_id) {
+    if (request_id > max_request_id_) {

[kinuko, 2011/12/14 03:39:22]

Please always omit (or use) the curly braces for single-line body.
(In chrome common style seems to be omitting { })

(Or we can just use std::max as satoru suggested offline)

[satorux1, 2011/12/14 04:43:26]

Done.

+      max_request_id_ = request_id;
+    }
+    return base::Bind(&MemoryFileUtilTest::StatusCallbackImpl,
+                      base::Unretained(this),
+                      request_id);
+  }
+
+  FileUtilAsync::GetFileInfoCallback GetGetFileInfoCallback(
+      int request_id) {
+    if (request_id > max_request_id_) {
+      max_request_id_ = request_id;
+    }
+    return base::Bind(&MemoryFileUtilTest::GetFileInfoCallback,
+                      base::Unretained(this),
+                      request_id);
+  }
+
+  FileUtilAsync::OpenCallback GetOpenCallback(int request_id) {
+    if (request_id > max_request_id_) {
+      max_request_id_ = request_id;
+    }
+    return base::Bind(&MemoryFileUtilTest::OpenCallback,
+                      base::Unretained(this),
+                      request_id);
+  }
+
+  ReadWriteCallback GetReadWriteCallback(int request_id) {
+    if (request_id > max_request_id_) {
+      max_request_id_ = request_id;
+    }
+    return base::Bind(&MemoryFileUtilTest::ReadWriteCallbackImpl,
+                      base::Unretained(this),
+                      request_id);
+  }
+
+  FileUtilAsync::ReadDirectoryCallback GetReadDirectoryCallback(
+      int request_id) {
+    if (request_id > max_request_id_) {
+      max_request_id_ = request_id;
+    }
+    return base::Bind(&MemoryFileUtilTest::ReadDirectoryCallback,
+                      base::Unretained(this),
+                      request_id);
+  }
+
+  int CreateEmptyFile(const FilePath& file_path) {
+    int request_id = GetNextRequestId();
+    file_util_->Create(file_path, GetStatusCallback(request_id));
+    return request_id;
+  }
+
+  int CreateNonEmptyFile(const FilePath& file_path,
+                         const char* data,
+                         int length) {
+    int request_id = GetNextRequestId();
+    file_util_->Open(
+        file_path,
+        base::PLATFORM_FILE_CREATE | base::PLATFORM_FILE_WRITE,
+        base::Bind(&MemoryFileUtilTest::WriteToOpenedFile,
+                   base::Unretained(this),
+                   request_id, data, length));
+    return request_id;
+  }
+
+  CallbackType GetStatusType(int request_id) {
+    if (status_map_.find(request_id) == status_map_.end())
+      return CALLBACK_TYPE_ERROR;
+    return status_map_[request_id].type;
+  }
+
+  // Return the operation status.
+  CallbackStatus& GetStatus(int request_id) {
+    return status_map_[request_id];
+  }
+
+  int StatusQueueSize() {
+    return status_map_.size();
+  }
+
+  int GetNextRequestId() {
+    return ++max_request_id_;
+  }
+
+  void set_read_directory_buffer_size(int size) {
+    file_util_->set_read_directory_buffer_size(size);
+  }
+
+ private:
+  void StatusCallbackImpl(int request_id, PlatformFileError result) {
+    CallbackStatus status;
+    status.type = CALLBACK_TYPE_STATUS;
+    status.result = result;
+    status_map_[request_id] = status;
+  }
+
+  void GetFileInfoCallback(int request_id,
+                           PlatformFileError result,
+                           const base::PlatformFileInfo& file_info) {
+    CallbackStatus status;
+    status.type = CALLBACK_TYPE_GET_FILE_INFO;
+    status.result = result;
+    status.file_info = file_info;
+    status_map_[request_id] = status;
+  }
+
+  void OpenCallback(int request_id,
+                    PlatformFileError result,
+                    AsyncFileStream* file_stream) {
+    CallbackStatus status;
+    status.type = CALLBACK_TYPE_OPEN;
+    status.result = result;
+    status.file_stream = file_stream;
+    status_map_[request_id] = status;
+  }
+
+  void ReadWriteCallbackImpl(int request_id,
+                             PlatformFileError result,
+                             int64 length) {
+    CallbackStatus status;
+    status.type = CALLBACK_TYPE_READ_WRITE;
+    status.result = result;
+    status.length = length;
+    status_map_[request_id] = status;
+  }
+
+  void ReadDirectoryCallback(int request_id,
+                             PlatformFileError result,
+                             const FileUtilAsync::FileList& entries,
+                             bool completed) {
+    if (status_map_.find(request_id) == status_map_.end()) {
+      CallbackStatus status;
+      status.type = CALLBACK_TYPE_READ_DIRECTORY;
+      status.called_after_completed = false;
+      status.result = result;
+      status.completed = completed;
+      status.called = 1;
+      status.entries = entries;
+      status_map_[request_id] = status;
+    } else {
+      CallbackStatus& status = status_map_[request_id];
+      if (status.completed)
+        status.called_after_completed = true;
+      status.result = result;
+      status.completed = completed;
+      ++status.called;
+      status.entries.insert(status.entries.begin(), entries.begin(),
+                            entries.end());
+    }
+  }
+
+  void WriteToOpenedFile(int request_id,
+                         const char* data,
+                         int length,
+                         PlatformFileError result,
+                         AsyncFileStream* stream) {
+    CallbackStatus status;
+    status.type = CALLBACK_TYPE_OPEN;
+    status.result = result;
+    status_map_[request_id] = status;
+    stream->Write(data, length, GetReadWriteCallback(GetNextRequestId()));
+  }
+
+  scoped_ptr<MemoryFileUtil> file_util_;
+  std::map<int, CallbackStatus> status_map_;
+  int max_request_id_;
+
+  DISALLOW_COPY_AND_ASSIGN(MemoryFileUtilTest);
+};
+
+TEST_F(MemoryFileUtilTest, TestCreateGetFileInfo) {
+  file_util()->GetFileInfo(FilePath("/mnt/memory/test.txt"),
+                           GetGetFileInfoCallback(1));
+
+  // TODO(olege): In case the file system is truely asynchronous, RunAllPending
+  // is not enough to wait for answer. In that case the thread should be blocked
+  // until the callback is called.

[kinuko, 2011/12/14 03:39:22]

Is this really a TODO comment or just a note for other fs implementors?

[satorux1, 2011/12/14 04:43:26]

Looks like a note. Removed TODO, and added some more comment.

+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(CALLBACK_TYPE_GET_FILE_INFO, GetStatusType(1));
+  CallbackStatus status = GetStatus(1);
+  ASSERT_EQ(base::PLATFORM_FILE_ERROR_NOT_FOUND, status.result);
+
+  base::Time start_create = base::Time::Now();
+
+  file_util()->Create(FilePath("/mnt/memory/test.txt"),

[kinuko, 2011/12/14 03:39:22]

I prefer using (local) const variables if we refer these values repeatedly.

[satorux1, 2011/12/14 04:43:26]

Let's keep it as is. file_util() is inlined anyway.

+                      GetStatusCallback(2));
+  MessageLoop::current()->RunAllPending();
+  ASSERT_EQ(CALLBACK_TYPE_STATUS, GetStatusType(2));
+  status = GetStatus(2);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+
+  file_util()->GetFileInfo(FilePath("/mnt/memory/test.txt"),
+                           GetGetFileInfoCallback(3));
+  MessageLoop::current()->RunAllPending();
+
+  base::Time end_create = base::Time::Now();
+
+  ASSERT_EQ(CALLBACK_TYPE_GET_FILE_INFO, GetStatusType(3));
+  status = GetStatus(3);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+  ASSERT_EQ(0, status.file_info.size);
+  ASSERT_FALSE(status.file_info.is_directory);
+  ASSERT_FALSE(status.file_info.is_symbolic_link);
+  ASSERT_GE(status.file_info.last_modified, start_create);
+  ASSERT_LE(status.file_info.last_modified, end_create);
+  ASSERT_GE(status.file_info.creation_time, start_create);
+  ASSERT_LE(status.file_info.creation_time, end_create);
+}
+
+TEST_F(MemoryFileUtilTest, TestReadWrite) {
+  // Check that the file does not exist.
+
+  file_util()->GetFileInfo(FilePath("/mnt/memory/test1.txt"),
+                           GetGetFileInfoCallback(1));
+
+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(CALLBACK_TYPE_GET_FILE_INFO, GetStatusType(1));
+  CallbackStatus status = GetStatus(1);
+  ASSERT_EQ(base::PLATFORM_FILE_ERROR_NOT_FOUND, status.result);
+
+  // Create & open file for writing.
+
+  base::Time start_create = base::Time::Now();
+  file_util()->Open(FilePath("/mnt/memory/test1.txt"),
+                    base::PLATFORM_FILE_CREATE_ALWAYS |
+                    base::PLATFORM_FILE_WRITE,
+                    GetOpenCallback(2));
+  MessageLoop::current()->RunAllPending();
+
+  base::Time end_create = base::Time::Now();
+
+  ASSERT_EQ(CALLBACK_TYPE_OPEN, GetStatusType(2));
+  status = GetStatus(2);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+
+  AsyncFileStream* write_file_stream = status.file_stream;
+
+  // Check that file was created and has 0 size.
+
+  file_util()->GetFileInfo(FilePath("/mnt/memory/test1.txt"),
+                           GetGetFileInfoCallback(3));
+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(CALLBACK_TYPE_GET_FILE_INFO, GetStatusType(3));
+  status = GetStatus(3);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+  ASSERT_EQ(0, status.file_info.size);
+  ASSERT_FALSE(status.file_info.is_directory);
+  ASSERT_FALSE(status.file_info.is_symbolic_link);
+  ASSERT_GE(status.file_info.last_modified, start_create);
+  ASSERT_LE(status.file_info.last_modified, end_create);
+
+  // Write 10 bytes to file.
+
+  base::Time start_write = base::Time::Now();
+  write_file_stream->Write(kTestString, 10,
+                           GetReadWriteCallback(4));
+  MessageLoop::current()->RunAllPending();
+  base::Time end_write = base::Time::Now();
+
+  ASSERT_EQ(CALLBACK_TYPE_READ_WRITE, GetStatusType(4));
+  status = GetStatus(4);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+  ASSERT_EQ(10, status.length);
+
+  // Check that the file has now size 10 and correct modification time.
+
+  file_util()->GetFileInfo(FilePath("/mnt/memory/test1.txt"),
+                           GetGetFileInfoCallback(5));
+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(CALLBACK_TYPE_GET_FILE_INFO, GetStatusType(5));
+  status = GetStatus(5);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+  ASSERT_EQ(10, status.file_info.size);
+  ASSERT_GE(status.file_info.last_modified, start_write);
+  ASSERT_LE(status.file_info.last_modified, end_write);
+
+  // Write the rest of the string to file.
+
+  start_write = base::Time::Now();
+  write_file_stream->Write(kTestString + 10,
+                           kTestStringLength - 10,
+                           GetReadWriteCallback(6));
+  MessageLoop::current()->RunAllPending();
+  end_write = base::Time::Now();
+
+  ASSERT_EQ(CALLBACK_TYPE_READ_WRITE, GetStatusType(6));
+  status = GetStatus(6);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+  ASSERT_EQ(static_cast<int64>(kTestStringLength) - 10, status.length);
+
+  // Check the file size & modification time.
+
+  file_util()->GetFileInfo(FilePath("/mnt/memory/test1.txt"),
+                           GetGetFileInfoCallback(7));
+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(CALLBACK_TYPE_GET_FILE_INFO, GetStatusType(7));
+  status = GetStatus(7);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+  ASSERT_EQ(static_cast<int64>(kTestStringLength), status.file_info.size);
+  ASSERT_GE(status.file_info.last_modified, start_write);
+  ASSERT_LE(status.file_info.last_modified, end_write);
+
+  // Open file for reading.
+
+  file_util()->Open(FilePath("/mnt/memory/test1.txt"),
+                    base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_READ,
+                    GetOpenCallback(8));

[kinuko, 2011/12/14 03:39:22]

This code would make it hard to add other test snippets in the mid of the test
sequence-- can't we simply use GetNextRequestId everywhere?

[satorux1, 2011/12/14 04:43:26]

Done.

+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(CALLBACK_TYPE_OPEN, GetStatusType(8));
+  status = GetStatus(8);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+
+  scoped_ptr<AsyncFileStream> read_file_stream(status.file_stream);
+
+  // Read the whole file
+  char buffer[1024];
+  read_file_stream->Read(buffer, 1023, GetReadWriteCallback(9));
+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(CALLBACK_TYPE_READ_WRITE, GetStatusType(9));
+  status = GetStatus(9);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+  ASSERT_EQ(static_cast<int64>(kTestStringLength), status.length);
+
+  buffer[status.length] = '\0';
+  std::string result_string(buffer);
+  ASSERT_EQ(kTestString, result_string);
+
+  // Check that size & modification time have not changed.
+
+  file_util()->GetFileInfo(FilePath("/mnt/memory/test1.txt"),
+                           GetGetFileInfoCallback(10));
+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(CALLBACK_TYPE_GET_FILE_INFO, GetStatusType(10));
+  status = GetStatus(10);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+  ASSERT_EQ(static_cast<int64>(kTestStringLength), status.file_info.size);
+  ASSERT_GE(status.file_info.last_modified, start_write);
+  ASSERT_LE(status.file_info.last_modified, end_write);
+
+  // Open once more for writing.
+
+  file_util()->Open(FilePath("/mnt/memory/test1.txt"),
+                    base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_WRITE,
+                    GetOpenCallback(11));
+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(CALLBACK_TYPE_OPEN, GetStatusType(11));
+  status = GetStatus(11);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+
+  scoped_ptr<AsyncFileStream> write_file_stream2(status.file_stream);
+
+  // Check that the size has not changed.
+
+  file_util()->GetFileInfo(FilePath("/mnt/memory/test1.txt"),
+                           GetGetFileInfoCallback(12));
+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(CALLBACK_TYPE_GET_FILE_INFO, GetStatusType(12));
+  status = GetStatus(12);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+  ASSERT_EQ(static_cast<int64>(kTestStringLength), status.file_info.size);
+
+  // Seek beyond the end of file. Should return error.
+
+  write_file_stream2->Seek(1000, GetStatusCallback(13));
+  MessageLoop::current()->RunAllPending();
+  ASSERT_EQ(CALLBACK_TYPE_STATUS, GetStatusType(13));
+  status = GetStatus(13);
+  ASSERT_EQ(base::PLATFORM_FILE_ERROR_INVALID_OPERATION, status.result);
+
+  // Try to write to read-only stream.
+
+  read_file_stream->Write(kTestString,
+                          kTestStringLength,
+                          GetReadWriteCallback(14));
+  MessageLoop::current()->RunAllPending();
+  status = GetStatus(14);
+  ASSERT_EQ(base::PLATFORM_FILE_ERROR_INVALID_OPERATION, status.result);
+
+  // Write data overlapping with already written.
+
+
+  write_file_stream2->Seek(10, GetStatusCallback(15));
+  MessageLoop::current()->RunAllPending();
+  ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(15).result);
+
+  write_file_stream2->Write(kTestString,
+                            kTestStringLength,
+                            GetReadWriteCallback(16));
+  MessageLoop::current()->RunAllPending();
+  status = GetStatus(16);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+  ASSERT_EQ(static_cast<int64>(kTestStringLength), status.length);
+
+  // Check size.
+
+  file_util()->GetFileInfo(FilePath("/mnt/memory/test1.txt"),
+                           GetGetFileInfoCallback(17));
+  MessageLoop::current()->RunAllPending();
+  status = GetStatus(17);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+  ASSERT_EQ(static_cast<int64>(kTestStringLength) + 10,
+            status.file_info.size);
+
+  // Read from 10th byte.
+  read_file_stream->Seek(10, GetStatusCallback(18));
+  MessageLoop::current()->RunAllPending();
+  ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(18).result);
+
+  read_file_stream->Read(buffer, 1023, GetReadWriteCallback(19));
+  MessageLoop::current()->RunAllPending();
+  status = GetStatus(19);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
+  ASSERT_EQ(static_cast<int64>(kTestStringLength), status.length);
+  buffer[status.length] = '\0';
+  std::string result_string2(buffer);
+  ASSERT_EQ(kTestString, result_string2);
+}
+
+// The directory structure we'll be testing on:
+// path                    size
+//
+// /mnt/memory/a           0
+// /mnt/memory/b/
+// /mnt/memory/b/c         kTestStringLength
+// /mnt/memory/b/d/
+// /mnt/memory/b/e         0
+// /mnt/memory/b/f         kTestStringLength
+// /mnt/memory/b/g/
+// /mnt/memory/b/g/h       0
+// /mnt/memory/b/i         kTestStringLength
+// /mnt/memory/c/
+// /mnt/memory/longer_file_name.txt kTestStringLength

[kinuko, 2011/12/14 03:39:22]

Can we define these test constants somewhere and make the test code a bit more
organized so that we can easily add/change test conditions?
(Not really mandatory since the memory_file_util itself is for testing (for now)
but would be nice to make it cleaner)

[satorux1, 2011/12/14 04:43:26]

I thought about it but constants may make the code less readable as we cannot
use / in file names. Let's revisit this when needed. 

[satorux1, 2011/12/14 04:44:40]

I meant variable names.

+TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
+  // Check the directory is empty.
+  file_util()->ReadDirectory(FilePath("/mnt/memory/"),
+                             GetReadDirectoryCallback(1));
+
+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(CALLBACK_TYPE_READ_DIRECTORY, GetStatusType(1));
+  CallbackStatus& status = GetStatus(1);
+  ASSERT_TRUE(status.completed);
+  ASSERT_FALSE(status.called_after_completed);
+  ASSERT_EQ(1, status.called);
+  ASSERT_EQ(0u, status.entries.size());
+
+  // Create /mnt/memory/a, /mnt/memory/b/, /mnt/memory/longer_file_name.txt,
+  // /mnt/memory/c/ asyncronously (i.e. we do not wait for each operation to
+  // complete before starting the next one.
+
+  base::Time start_create = base::Time::Now();
+  CreateEmptyFile(FilePath("/mnt/memory/a"));
+
+  int request_id1 = GetNextRequestId();
+  file_util()->CreateDirectory(FilePath("/mnt/memory/b"),
+                               GetStatusCallback(request_id1));
+
+  CreateNonEmptyFile(FilePath("/mnt/memory/longer_file_name.txt"),
+                     kTestString,
+                     kTestStringLength);
+
+  int request_id2 = GetNextRequestId();
+  file_util()->CreateDirectory(FilePath("/mnt/memory/c"),
+                               GetStatusCallback(request_id2));
+
+  MessageLoop::current()->RunAllPending();
+  base::Time end_create = base::Time::Now();
+
+  ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(request_id1).result);
+  ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(request_id2).result);
+
+  // ReadDirectory /mnt/memory, /mnt/memory/a (not a dir), /mnt/memory/b/,
+  // /mnt/memory/d (not found)
+
+  set_read_directory_buffer_size(5);  // Should complete in one go.
+
+  request_id1 = GetNextRequestId();
+  file_util()->ReadDirectory(FilePath("/mnt/memory"),
+                             GetReadDirectoryCallback(request_id1));
+  request_id2 = GetNextRequestId();
+  file_util()->ReadDirectory(FilePath("/mnt/memory/a"),
+                             GetReadDirectoryCallback(request_id2));
+  int request_id3 = GetNextRequestId();
+  file_util()->ReadDirectory(FilePath("/mnt/memory/b/"),
+                             GetReadDirectoryCallback(request_id3));
+  int request_id4 = GetNextRequestId();
+  file_util()->ReadDirectory(FilePath("/mnt/memory/d/"),
+                             GetReadDirectoryCallback(request_id4));
+
+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(request_id1).result);
+  status = GetStatus(request_id1);
+  ASSERT_TRUE(status.completed);
+  ASSERT_FALSE(status.called_after_completed);
+  ASSERT_EQ(1, status.called);  // Because the number of entries < 5.
+  ASSERT_EQ(4u, status.entries.size());
+
+  std::set<FilePath::StringType> seen;
+
+  for (FileUtilAsync::FileList::const_iterator it = status.entries.begin();
+       it != status.entries.end();
+       ++it) {
+    ASSERT_LE(start_create, it->last_modified_time);
+    ASSERT_GE(end_create, it->last_modified_time);
+
+    ASSERT_EQ(seen.end(), seen.find(it->name));
+    seen.insert(it->name);
+
+    if (it->name == "a") {
+      ASSERT_FALSE(it->is_directory);
+      ASSERT_EQ(0, it->size);
+    } else if (it->name == "b") {
+      ASSERT_TRUE(it->is_directory);
+    } else if (it->name == "c") {
+      ASSERT_TRUE(it->is_directory);
+    } else if (it->name == "longer_file_name.txt") {
+      ASSERT_FALSE(it->is_directory);
+      ASSERT_EQ(static_cast<int64>(kTestStringLength), it->size);
+    } else {
+      LOG(ERROR) << "Unexpected file: " << it->name;
+      ASSERT_TRUE(false);
+    }
+  }
+
+  ASSERT_EQ(base::PLATFORM_FILE_ERROR_NOT_A_DIRECTORY,
+            GetStatus(request_id2).result);
+
+  status = GetStatus(request_id3);
+  ASSERT_TRUE(status.completed);
+  ASSERT_FALSE(status.called_after_completed);
+  ASSERT_EQ(1, status.called);
+  ASSERT_EQ(0u, status.entries.size());
+
+  ASSERT_EQ(base::PLATFORM_FILE_ERROR_NOT_FOUND, GetStatus(request_id4).result);
+
+  // Create files & dirs inside b/:
+  // /mnt/memory/b/c         kTestStringLength
+  // /mnt/memory/b/d/
+  // /mnt/memory/b/e         0
+  // /mnt/memory/b/f         kTestStringLength
+  // /mnt/memory/b/g/
+  // /mnt/memory/b/i         kTestStringLength
+  //
+  // /mnt/memory/b/g/h       0
+
+  start_create = base::Time::Now();
+  CreateNonEmptyFile(FilePath("/mnt/memory/b/c"),
+                     kTestString,
+                     kTestStringLength);
+  request_id1 = GetNextRequestId();
+  file_util()->CreateDirectory(FilePath("/mnt/memory/b/d"),
+                               GetStatusCallback(request_id1));
+  CreateEmptyFile(FilePath("/mnt/memory/b/e"));
+  CreateNonEmptyFile(FilePath("/mnt/memory/b/f"),
+                     kTestString,
+                     kTestStringLength);
+  request_id2 = GetNextRequestId();
+  file_util()->CreateDirectory(FilePath("/mnt/memory/b/g"),
+                               GetStatusCallback(request_id1));
+  CreateNonEmptyFile(FilePath("/mnt/memory/b/i"),
+                     kTestString,
+                     kTestStringLength);
+
+  MessageLoop::current()->RunAllPending();
+
+  CreateEmptyFile(FilePath("/mnt/memory/b/g/h"));
+
+  MessageLoop::current()->RunAllPending();
+  end_create = base::Time::Now();
+
+  // Read /mnt/memory and check that the number of entries is unchanged.
+
+  request_id1 = GetNextRequestId();
+  file_util()->ReadDirectory(FilePath("/mnt/memory"),
+                             GetReadDirectoryCallback(request_id1));
+
+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(request_id1).result);
+  status = GetStatus(request_id1);
+  ASSERT_TRUE(status.completed);
+  ASSERT_FALSE(status.called_after_completed);
+  ASSERT_EQ(1, status.called);  // Because the number of entries < 5.
+  ASSERT_EQ(4u, status.entries.size());
+
+  // Read /mnt/memory/b
+
+  request_id1 = GetNextRequestId();
+  file_util()->ReadDirectory(FilePath("/mnt/memory/b"),
+                             GetReadDirectoryCallback(request_id1));
+
+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(request_id1).result);
+  status = GetStatus(request_id1);
+  ASSERT_TRUE(status.completed);
+  ASSERT_FALSE(status.called_after_completed);
+  ASSERT_EQ(2, status.called);  // Because the number of entries > 5.
+  ASSERT_EQ(6u, status.entries.size());
+
+  seen.clear();
+
+  for (FileUtilAsync::FileList::const_iterator it = status.entries.begin();
+       it != status.entries.end();
+       ++it) {
+    ASSERT_LE(start_create, it->last_modified_time);
+    ASSERT_GE(end_create, it->last_modified_time);
+
+    ASSERT_EQ(seen.end(), seen.find(it->name));
+    seen.insert(it->name);
+
+    // /mnt/memory/b/c         kTestStringLength
+    // /mnt/memory/b/d/
+    // /mnt/memory/b/e         0
+    // /mnt/memory/b/f         kTestStringLength
+    // /mnt/memory/b/g/
+    // /mnt/memory/b/i         kTestStringLength
+
+    if (it->name == "c") {
+      ASSERT_FALSE(it->is_directory);
+      ASSERT_EQ(static_cast<int64>(kTestStringLength), it->size);
+    } else if (it->name == "d") {
+      ASSERT_TRUE(it->is_directory);
+    } else if (it->name == "e") {
+      ASSERT_FALSE(it->is_directory);
+      ASSERT_EQ(0, it->size);
+    } else if (it->name == "f") {
+      ASSERT_FALSE(it->is_directory);
+      ASSERT_EQ(static_cast<int64>(kTestStringLength), it->size);
+    } else if (it->name == "g") {
+      ASSERT_TRUE(it->is_directory);
+    } else if (it->name == "i") {
+      ASSERT_FALSE(it->is_directory);
+      ASSERT_EQ(static_cast<int64>(kTestStringLength), it->size);
+    } else {
+      LOG(ERROR) << "Unexpected file: " << it->name;
+      ASSERT_TRUE(false);
+    }
+  }
+
+  // Remove single file: /mnt/memory/b/f
+
+  request_id1 = GetNextRequestId();
+  file_util()->Remove(FilePath("/mnt/memory/b/f"), false /* recursive */,
+                      GetStatusCallback(request_id1));
+  MessageLoop::current()->RunAllPending();
+  ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(request_id1).result);
+
+  // Check the number of files in b/
+
+  request_id1 = GetNextRequestId();
+  file_util()->ReadDirectory(FilePath("/mnt/memory/b"),
+                             GetReadDirectoryCallback(request_id1));
+
+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(request_id1).result);
+  status = GetStatus(request_id1);
+  ASSERT_TRUE(status.completed);
+  ASSERT_FALSE(status.called_after_completed);
+  ASSERT_EQ(5u, status.entries.size());
+
+  // Try remove /mnt/memory/b non-recursively (error)
+
+  request_id1 = GetNextRequestId();
+  file_util()->Remove(FilePath("/mnt/memory/b"), false /* recursive */,
+                      GetStatusCallback(request_id1));
+  MessageLoop::current()->RunAllPending();
+  ASSERT_EQ(base::PLATFORM_FILE_ERROR_NOT_A_FILE,
+            GetStatus(request_id1).result);
+
+  // Non-recursively remove empty directory.
+
+  request_id1 = GetNextRequestId();
+  file_util()->Remove(FilePath("/mnt/memory/b/d"), false,
+                      GetStatusCallback(request_id1));
+  MessageLoop::current()->RunAllPending();
+  ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(request_id1).result);
+
+  request_id1 = GetNextRequestId();
+  file_util()->GetFileInfo(FilePath("/mnt/memory/b/d"),
+                           GetGetFileInfoCallback(request_id1));
+  MessageLoop::current()->RunAllPending();
+  ASSERT_EQ(base::PLATFORM_FILE_ERROR_NOT_FOUND, GetStatus(request_id1).result);
+
+  // Remove /mnt/memory/b recursively.
+
+  request_id1 = GetNextRequestId();
+  file_util()->Remove(FilePath("/mnt/memory/b"), true /* recursive */,
+                      GetStatusCallback(request_id1));
+  MessageLoop::current()->RunAllPending();
+  ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(request_id1).result);
+
+  // ReadDirectory /mnt/memory/b -> not found
+
+  request_id1 = GetNextRequestId();
+  file_util()->ReadDirectory(FilePath("/mnt/memory/b"),
+                             GetReadDirectoryCallback(request_id1));
+  MessageLoop::current()->RunAllPending();
+  ASSERT_EQ(base::PLATFORM_FILE_ERROR_NOT_FOUND, GetStatus(request_id1).result);
+
+  // ReadDirectory /mnt/memory
+
+  request_id1 = GetNextRequestId();
+  file_util()->ReadDirectory(FilePath("/mnt/memory"),
+                             GetReadDirectoryCallback(request_id1));
+
+  MessageLoop::current()->RunAllPending();
+
+  ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(request_id1).result);
+  status = GetStatus(request_id1);
+  ASSERT_TRUE(status.completed);
+  ASSERT_FALSE(status.called_after_completed);
+  ASSERT_EQ(3u, status.entries.size());
+
+  seen.clear();
+
+  for (FileUtilAsync::FileList::const_iterator it = status.entries.begin();
+       it != status.entries.end();
+       ++it) {
+    ASSERT_EQ(seen.end(), seen.find(it->name));
+    seen.insert(it->name);
+
+    if (it->name == "a") {
+      ASSERT_FALSE(it->is_directory);
+      ASSERT_EQ(0, it->size);
+    } else if (it->name == "c") {
+      ASSERT_TRUE(it->is_directory);
+    } else if (it->name == "longer_file_name.txt") {
+      ASSERT_FALSE(it->is_directory);
+      ASSERT_EQ(static_cast<int64>(kTestStringLength), it->size);
+    } else {
+      LOG(ERROR) << "Unexpected file: " << it->name;
+      ASSERT_TRUE(false);
+    }
+  }
+}
+
+}  // namespace fileapi