Clean up ARC file system unit tests.

components/arc/test/fake_file_system_instance.cc

Index: components/arc/test/fake_file_system_instance.cc
diff --git a/components/arc/test/fake_file_system_instance.cc b/components/arc/test/fake_file_system_instance.cc
index a0a0aca33a31f367c5ebfe1b89565a64c568eced..81613d6853f049f7352e05a53b6e6fcfd5ccf200 100644
--- a/components/arc/test/fake_file_system_instance.cc
+++ b/components/arc/test/fake_file_system_instance.cc
@@ -4,48 +4,201 @@
 
 #include "components/arc/test/fake_file_system_instance.h"
 
+#include <string.h>
+#include <unistd.h>
+
 #include "base/bind.h"
+#include "base/files/file.h"
+#include "base/files/file_path.h"
+#include "base/files/file_util.h"
+#include "base/files/scoped_file.h"
 #include "base/location.h"
+#include "base/logging.h"
 #include "base/optional.h"
 #include "base/threading/thread_task_runner_handle.h"
-#include "mojo/public/cpp/system/handle.h"
+#include "mojo/edk/embedder/embedder.h"
 
 namespace arc {
 
-FakeFileSystemInstance::FakeFileSystemInstance() = default;
+namespace {
 
-FakeFileSystemInstance::~FakeFileSystemInstance() = default;
+base::ScopedFD CreateRegularFileDescriptor(const std::string& content,
+                                           const base::FilePath& temp_dir) {
+  base::FilePath path;
+  bool create_success = base::CreateTemporaryFileInDir(temp_dir, &path);
+  DCHECK(create_success);
+  int written_size = base::WriteFile(path, content.c_str(), content.size());

[hidehiko, 2017/01/27 15:50:00]

s/content.c_str()/constent.data()/

Here, std::string is used as a byte-buffer.
So, data() is more appropriate, I think, because c_str() means c-style string
(\0 terminate str) conceptually.
(Note, AFAIK, these are not much different in C++11, but for readability).

[Shuhei Takahashi, 2017/01/30 02:27:35]

I don't have any preference on this.

+  DCHECK_EQ(static_cast<int>(content.size()), written_size);
+  base::File file(path, base::File::FLAG_OPEN | base::File::FLAG_READ);
+  DCHECK(file.IsValid());
+  return base::ScopedFD(file.TakePlatformFile());
+}
 
-void FakeFileSystemInstance::GetChildDocuments(
+base::ScopedFD CreateStreamFileDescriptor(const std::string& content) {
+  int fds[2];
+  int ret = pipe(fds);
+  DCHECK_EQ(0, ret);
+  base::ScopedFD fd_read(fds[0]);
+  base::ScopedFD fd_write(fds[1]);
+  bool write_success = base::WriteFileDescriptor(
+      fd_write.get(), content.c_str(), content.size());

[hidehiko, 2017/01/27 15:50:00]

Ditto.

[Shuhei Takahashi, 2017/01/30 02:27:35]

Done.

+  DCHECK(write_success);
+  return fd_read;
+}
+
+mojom::DocumentPtr MakeDocument(const FakeFileSystemInstance::Document& doc) {
+  mojom::DocumentPtr document = mojom::Document::New();
+  document->document_id = doc.document_id;
+  document->display_name = doc.display_name;
+  document->mime_type = doc.mime_type;
+  document->size = doc.size;
+  document->last_modified = doc.last_modified;
+  return document;
+}
+
+}  // namespace
+
+FakeFileSystemInstance::File::File() = default;
+
+FakeFileSystemInstance::File::File(const File& rhs) = default;
+
+FakeFileSystemInstance::File::File(const std::string& url,
+                                   const std::string& content,
+                                   Seekable seekable)
+    : url(url), content(content), seekable(seekable) {}
+
+FakeFileSystemInstance::File::~File() = default;
+
+FakeFileSystemInstance::Document::Document() = default;
+
+FakeFileSystemInstance::Document::Document(const Document& rhs) = default;
+
+FakeFileSystemInstance::Document::Document(
     const std::string& authority,
     const std::string& document_id,
-    const GetChildDocumentsCallback& callback) {
-  base::ThreadTaskRunnerHandle::Get()->PostTask(
-      FROM_HERE, base::Bind(callback, base::nullopt));
+    const std::string& parent_document_id,
+    const std::string& display_name,
+    const std::string& mime_type,
+    int64_t size,
+    uint64_t last_modified)
+    : authority(authority),
+      document_id(document_id),
+      parent_document_id(parent_document_id),
+      display_name(display_name),
+      mime_type(mime_type),
+      size(size),
+      last_modified(last_modified) {}
+
+FakeFileSystemInstance::Document::~Document() = default;
+
+FakeFileSystemInstance::FakeFileSystemInstance() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  bool temp_dir_created = temp_dir_.CreateUniqueTempDir();
+  DCHECK(temp_dir_created);
 }
 
-void FakeFileSystemInstance::GetDocument(const std::string& authority,
-                                         const std::string& document_id,
-                                         const GetDocumentCallback& callback) {
-  base::ThreadTaskRunnerHandle::Get()->PostTask(
-      FROM_HERE, base::Bind(callback, base::Passed(mojom::DocumentPtr())));
+FakeFileSystemInstance::~FakeFileSystemInstance() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+}
+
+void FakeFileSystemInstance::AddFile(const File& file) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK_EQ(0u, files_.count(std::string(file.url)));
+  files_[std::string(file.url)] = file;
+}
+
+void FakeFileSystemInstance::AddDocument(const Document& document) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DocumentKey key(document.authority, document.document_id);
+  DCHECK_EQ(0u, documents_.count(key));
+  documents_[key] = document;
+  child_documents_[key];  // Allocate a vector.
+  if (!document.parent_document_id.empty()) {
+    DocumentKey parent_key(document.authority, document.parent_document_id);
+    DCHECK_EQ(1u, documents_.count(parent_key));
+    child_documents_[parent_key].push_back(key);
+  }
 }
 
 void FakeFileSystemInstance::GetFileSize(const std::string& url,
                                          const GetFileSizeCallback& callback) {
-  base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
-                                                base::Bind(callback, -1));
+  DCHECK(thread_checker_.CalledOnValidThread());
+  auto iter = files_.find(url);
+  if (iter == files_.end()) {
+    base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
+                                                  base::Bind(callback, -1));
+    return;
+  }
+  const File& file = iter->second;
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE, base::Bind(callback, file.content.size()));
 }
 
 void FakeFileSystemInstance::OpenFileToRead(
     const std::string& url,
     const OpenFileToReadCallback& callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  auto iter = files_.find(url);
+  if (iter == files_.end()) {
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE, base::Bind(callback, base::Passed(mojo::ScopedHandle())));
+    return;
+  }
+  const File& file = iter->second;
+  base::ScopedFD fd =
+      file.seekable == File::SEEKABLE
+          ? CreateRegularFileDescriptor(file.content, temp_dir_.GetPath())
+          : CreateStreamFileDescriptor(file.content);
+  mojo::edk::ScopedPlatformHandle platform_handle(
+      mojo::edk::PlatformHandle(fd.release()));
+  MojoHandle wrapped_handle;
+  MojoResult result = mojo::edk::CreatePlatformHandleWrapper(
+      std::move(platform_handle), &wrapped_handle);
+  DCHECK_EQ(MOJO_RESULT_OK, result);
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE, base::Bind(callback, base::Passed(mojo::ScopedHandle(
+                                          mojo::Handle(wrapped_handle)))));
+}
+
+void FakeFileSystemInstance::GetDocument(const std::string& authority,
+                                         const std::string& document_id,
+                                         const GetDocumentCallback& callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  auto iter = documents_.find(DocumentKey(authority, document_id));
+  if (iter == documents_.end()) {
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE, base::Bind(callback, base::Passed(mojom::DocumentPtr())));
+    return;
+  }
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE,
+      base::Bind(callback, base::Passed(MakeDocument(iter->second))));
+}
+
+void FakeFileSystemInstance::GetChildDocuments(
+    const std::string& authority,
+    const std::string& parent_document_id,
+    const GetChildDocumentsCallback& callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  auto iter = child_documents_.find(DocumentKey(authority, parent_document_id));
+  if (iter == child_documents_.end()) {
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE, base::Bind(callback, base::nullopt));
+    return;
+  }
+  std::vector<mojom::DocumentPtr> children;
+  for (const auto& child_key : iter->second) {
+    children.emplace_back(MakeDocument(documents_[child_key]));
+  }
   base::ThreadTaskRunnerHandle::Get()->PostTask(
-      FROM_HERE, base::Bind(callback, base::Passed(mojo::ScopedHandle())));
+      FROM_HERE,
+      base::Bind(callback,
+                 base::Passed(base::make_optional(std::move(children)))));
 }
 
 void FakeFileSystemInstance::RequestMediaScan(
     const std::vector<std::string>& paths) {
+  DCHECK(thread_checker_.CalledOnValidThread());
   // Do nothing and pretend we scaned them.
 }